0 00:00:00,000 --> 00:00:30,000 Dear viewer, these subtitles were generated by a machine via the service Trint and therefore are (very) buggy. If you are capable, please help us to create good quality subtitles: https://c3subtitles.de/talk/116 Thanks! 1 00:00:08,940 --> 00:00:11,019 Produce Doctor, 2 00:00:11,020 --> 00:00:13,339 a professor doctor, 3 00:00:13,340 --> 00:00:14,699 Dr. Robert C. 4 00:00:14,700 --> 00:00:16,799 Helling from the University 5 00:00:16,800 --> 00:00:18,989 of Munich. And 6 00:00:18,990 --> 00:00:21,209 please give a big hand for his 7 00:00:21,210 --> 00:00:22,949 presentation here on one of the most 8 00:00:22,950 --> 00:00:24,959 confusing topics that I ever had to read 9 00:00:24,960 --> 00:00:26,939 about when I was doing physics, which is 10 00:00:26,940 --> 00:00:28,199 supersymmetry. 11 00:00:28,200 --> 00:00:29,369 Thank you very much, Dr. Holly. 12 00:00:36,840 --> 00:00:38,069 OK. 13 00:00:38,070 --> 00:00:40,289 Thank you for coming to this prime 14 00:00:40,290 --> 00:00:41,460 time talk on day two. 15 00:00:43,980 --> 00:00:45,269 Yes, I am. 16 00:00:45,270 --> 00:00:46,889 My name's rover telling. I'm a physicist 17 00:00:46,890 --> 00:00:49,499 at Munich University and this 18 00:00:49,500 --> 00:00:51,899 talk is by request of a local 19 00:00:51,900 --> 00:00:54,089 brewer. Hacker asked 20 00:00:54,090 --> 00:00:55,830 me to talk about supersymmetry. 21 00:00:57,120 --> 00:01:00,179 So who knows? 22 00:01:00,180 --> 00:01:02,039 These people just got an idea. 23 00:01:02,040 --> 00:01:03,960 I'm over 40. Who else is over 40 24 00:01:06,690 --> 00:01:07,690 for particular, 25 00:01:08,760 --> 00:01:10,349 this lady? 26 00:01:10,350 --> 00:01:12,359 You all know her, but who recognize her? 27 00:01:13,440 --> 00:01:15,599 It's Madonna. Yes, it's 28 00:01:15,600 --> 00:01:17,759 a I can 80s 29 00:01:17,760 --> 00:01:18,760 movie picture. 30 00:01:19,770 --> 00:01:21,319 OK, so what is supersymmetry? 31 00:01:23,320 --> 00:01:25,499 We are talking about particle physics 32 00:01:25,500 --> 00:01:27,659 and supersymmetry or Susie. 33 00:01:27,660 --> 00:01:29,459 And chart is a symmetry that predicts 34 00:01:29,460 --> 00:01:31,049 that for every known species of 35 00:01:31,050 --> 00:01:33,510 particles, there is a new particle 36 00:01:35,190 --> 00:01:37,259 and not a single one 37 00:01:37,260 --> 00:01:38,730 of them has ever been observed. 38 00:01:40,800 --> 00:01:42,779 So why bother? 39 00:01:42,780 --> 00:01:45,029 And I will probably spend 40 00:01:45,030 --> 00:01:48,239 forty five minutes to explain why bother 41 00:01:48,240 --> 00:01:49,199 us? 42 00:01:49,200 --> 00:01:51,149 So I want to explain why my colleagues 43 00:01:51,150 --> 00:01:53,189 have come up with this idea of 44 00:01:53,190 --> 00:01:54,190 supersymmetry 45 00:01:55,440 --> 00:01:56,969 because it solves some of the big, 46 00:01:56,970 --> 00:01:59,159 outstanding problems in particle physics 47 00:01:59,160 --> 00:02:01,079 and theoretical high energy physics and 48 00:02:01,080 --> 00:02:03,899 in general. So but I have to explain 49 00:02:03,900 --> 00:02:06,089 a couple of things. So a brief 50 00:02:06,090 --> 00:02:08,579 introduction of first, 51 00:02:08,580 --> 00:02:10,769 the known players that is the standard 52 00:02:10,770 --> 00:02:12,749 model of particle physics that consists 53 00:02:12,750 --> 00:02:14,849 of matter particles, 54 00:02:14,850 --> 00:02:16,949 namely the leptons of 55 00:02:16,950 --> 00:02:18,539 they all have spin one half. 56 00:02:18,540 --> 00:02:19,859 This is the spin. 57 00:02:19,860 --> 00:02:21,779 That's the angular momentum, the 58 00:02:21,780 --> 00:02:23,339 intrinsic angle angle, the momentum of 59 00:02:23,340 --> 00:02:25,829 the particle. Most well known of this, 60 00:02:25,830 --> 00:02:28,109 these particle is the electron 61 00:02:28,110 --> 00:02:30,569 here depicted as E. 62 00:02:30,570 --> 00:02:32,669 And there are also neutrinos you might 63 00:02:32,670 --> 00:02:34,679 have heard of about those because there 64 00:02:34,680 --> 00:02:36,869 were some rumors that they could 65 00:02:36,870 --> 00:02:38,549 travel faster than light that turned out 66 00:02:38,550 --> 00:02:40,739 to be a problematic 67 00:02:40,740 --> 00:02:41,740 cable. 68 00:02:44,280 --> 00:02:45,989 But these two? 69 00:02:45,990 --> 00:02:48,509 So this one is everyday 70 00:02:48,510 --> 00:02:49,709 physics and chemistry. 71 00:02:49,710 --> 00:02:51,329 This one is very light. 72 00:02:51,330 --> 00:02:53,669 They have heavy, the electron is heavier 73 00:02:53,670 --> 00:02:55,109 partners, and there are also neutrinos 74 00:02:55,110 --> 00:02:56,489 for these part, and it's called This is 75 00:02:56,490 --> 00:02:58,739 the meal on. This is the town. 76 00:02:58,740 --> 00:03:00,629 And then in addition. 77 00:03:00,630 --> 00:03:02,759 So these guys make up the hull 78 00:03:02,760 --> 00:03:04,919 of an atom, and the 79 00:03:04,920 --> 00:03:06,989 core of the nucleus 80 00:03:06,990 --> 00:03:08,160 of an atom is made up 81 00:03:09,300 --> 00:03:10,889 out of quarks and neutrons. 82 00:03:10,890 --> 00:03:12,899 And those consist out of quarks, namely 83 00:03:12,900 --> 00:03:15,869 of these up and down quarks, but that 84 00:03:15,870 --> 00:03:17,999 form more types of quarks called 85 00:03:18,000 --> 00:03:19,830 chom strange bottom and top. 86 00:03:21,600 --> 00:03:22,620 And then there are 87 00:03:23,730 --> 00:03:26,069 four forces in the universe. 88 00:03:26,070 --> 00:03:28,139 One is gravity that doesn't matter for 89 00:03:28,140 --> 00:03:29,939 elementary particles. 90 00:03:29,940 --> 00:03:32,039 The others are mediated 91 00:03:32,040 --> 00:03:33,779 by particles again. 92 00:03:33,780 --> 00:03:35,939 Those have spin one, and the 93 00:03:35,940 --> 00:03:38,369 most well-known is the gamma particle, 94 00:03:38,370 --> 00:03:40,169 or the photon that's responsible for 95 00:03:40,170 --> 00:03:41,459 electromagnetism. 96 00:03:41,460 --> 00:03:43,589 But that's also the W and 97 00:03:43,590 --> 00:03:45,899 the Z vector boson that 98 00:03:45,900 --> 00:03:48,059 mediates the weak 99 00:03:48,060 --> 00:03:50,279 interaction that is responsible for beta 100 00:03:50,280 --> 00:03:51,280 decay. 101 00:03:52,080 --> 00:03:54,089 And there are gluons that actually keep 102 00:03:54,090 --> 00:03:55,919 these quarks together in the nucleus 103 00:03:55,920 --> 00:03:56,920 then. 104 00:03:57,750 --> 00:03:59,969 And then since this 105 00:03:59,970 --> 00:04:02,129 year, we know that there is actually 106 00:04:02,130 --> 00:04:04,559 another particle of spin zero 107 00:04:04,560 --> 00:04:06,119 and that's called the Higgs boson. 108 00:04:06,120 --> 00:04:07,979 And this year, the Nobel Prize was given 109 00:04:07,980 --> 00:04:09,389 for the discovery of actually for the 110 00:04:09,390 --> 00:04:11,069 prediction of this particle. 111 00:04:11,070 --> 00:04:12,240 So that is 112 00:04:13,260 --> 00:04:14,549 the standard model. These are the 113 00:04:14,550 --> 00:04:16,859 particles that we have all by now seen, 114 00:04:16,860 --> 00:04:18,958 and they fit well into this model 115 00:04:18,959 --> 00:04:20,129 called the standard model. 116 00:04:20,130 --> 00:04:21,389 Now come supersymmetry 117 00:04:22,440 --> 00:04:25,049 and for each and every one of those, 118 00:04:25,050 --> 00:04:26,369 there's a new partner. 119 00:04:26,370 --> 00:04:28,059 So now we're talking about the minimally 120 00:04:28,060 --> 00:04:30,449 supersymmetric star model that minimally 121 00:04:30,450 --> 00:04:32,579 refers to. We're adding as little 122 00:04:32,580 --> 00:04:34,109 as possible. 123 00:04:34,110 --> 00:04:36,299 So for these, X equals 124 00:04:36,300 --> 00:04:39,059 one half particles we add 125 00:04:39,060 --> 00:04:41,339 as equals zero particles called this 126 00:04:41,340 --> 00:04:42,239 leptons. 127 00:04:42,240 --> 00:04:44,159 You get their names by adding an X. 128 00:04:44,160 --> 00:04:46,379 So that's the electron, that's 129 00:04:46,380 --> 00:04:48,269 the smidgeon. And that's the star 130 00:04:49,440 --> 00:04:50,819 as well as the squawks. 131 00:04:54,000 --> 00:04:55,259 And then to these 132 00:04:56,280 --> 00:04:58,889 force particles that are 133 00:04:58,890 --> 00:05:01,289 fermions with SW equals one half 134 00:05:01,290 --> 00:05:04,019 called the photo for the photon, 135 00:05:04,020 --> 00:05:06,449 the winos and the Xenos for the W 136 00:05:06,450 --> 00:05:08,789 and the Z. You see the way adding an 137 00:05:08,790 --> 00:05:11,489 igloo we know are actually several one 138 00:05:11,490 --> 00:05:13,859 for the gluons plus Higgs, 139 00:05:13,860 --> 00:05:14,860 you know. 140 00:05:17,370 --> 00:05:20,489 And to make things internally consistent, 141 00:05:20,490 --> 00:05:22,349 this doesn't quite work. 142 00:05:22,350 --> 00:05:24,149 We have to add another pair of Higgs and 143 00:05:24,150 --> 00:05:26,369 Higgs xeno to make things work. 144 00:05:26,370 --> 00:05:27,989 So this is the minimally supersymmetric 145 00:05:27,990 --> 00:05:30,089 standard model, and I will be talking 146 00:05:30,090 --> 00:05:31,090 mostly about this 147 00:05:32,650 --> 00:05:35,489 set up of elementary particles. 148 00:05:35,490 --> 00:05:37,720 These. Has covered these hypothetical, 149 00:05:39,490 --> 00:05:41,799 and then there's an important principle 150 00:05:41,800 --> 00:05:44,289 and quantum physics that 151 00:05:44,290 --> 00:05:46,179 particles are fields. 152 00:05:46,180 --> 00:05:47,649 So there's the this is the 153 00:05:47,650 --> 00:05:49,599 electromagnetic field, but it's described 154 00:05:49,600 --> 00:05:52,239 by photon particle 155 00:05:52,240 --> 00:05:54,129 and the fields are again particles. 156 00:05:54,130 --> 00:05:56,289 So I will and the rest 157 00:05:56,290 --> 00:05:58,300 of the talk. Use this synonymously. 158 00:06:00,690 --> 00:06:02,909 OK, so I claimed there 159 00:06:02,910 --> 00:06:05,069 are open problems that 160 00:06:05,070 --> 00:06:07,229 are solved by assuming supersymmetry 161 00:06:07,230 --> 00:06:08,879 is a symmetry of nature. 162 00:06:08,880 --> 00:06:10,629 And I have five of them listed here. 163 00:06:10,630 --> 00:06:12,929 The first is actually very close 164 00:06:12,930 --> 00:06:13,949 to my heart. 165 00:06:15,240 --> 00:06:16,919 Up when I'm actually doing research, 166 00:06:16,920 --> 00:06:18,509 that's the mathematics of quantum field 167 00:06:18,510 --> 00:06:19,510 theory. 168 00:06:20,160 --> 00:06:21,839 But unfortunately, I won't talk about 169 00:06:21,840 --> 00:06:22,840 this. 170 00:06:23,680 --> 00:06:24,680 I'm 171 00:06:26,310 --> 00:06:28,019 the next one. 172 00:06:28,020 --> 00:06:29,639 This will take quite a while to explain 173 00:06:29,640 --> 00:06:30,690 it's called naturalness. 174 00:06:31,860 --> 00:06:34,229 Susie provides a solution 175 00:06:34,230 --> 00:06:36,089 to the natural problem, and to explain 176 00:06:36,090 --> 00:06:38,939 this, I have to go on a small detour. 177 00:06:38,940 --> 00:06:41,939 I have to explain how we 178 00:06:41,940 --> 00:06:44,189 theoretical physicist in 179 00:06:44,190 --> 00:06:46,769 the 21st century view 180 00:06:46,770 --> 00:06:48,899 these force fields, in particular 181 00:06:48,900 --> 00:06:50,099 the electromagnetic field. 182 00:06:50,100 --> 00:06:51,719 So this is how everybody learns what 183 00:06:51,720 --> 00:06:53,309 electromagnet magnetism is. 184 00:06:53,310 --> 00:06:54,929 You have a wonderful generator and that 185 00:06:54,930 --> 00:06:56,849 makes your hair go up and you have 186 00:06:56,850 --> 00:06:59,789 charges and force fields. 187 00:06:59,790 --> 00:07:03,269 And this is this electromagnetism 101. 188 00:07:03,270 --> 00:07:05,789 But I want I. 189 00:07:05,790 --> 00:07:08,069 I ask you to believe me 190 00:07:08,070 --> 00:07:09,749 that there is a completely different 191 00:07:09,750 --> 00:07:11,639 point of view that actually talking about 192 00:07:11,640 --> 00:07:14,129 the same thing than electric 193 00:07:14,130 --> 00:07:15,659 and magnetic fields, and that goes like 194 00:07:15,660 --> 00:07:16,660 this. So 195 00:07:18,570 --> 00:07:19,649 let's assume so. 196 00:07:19,650 --> 00:07:21,989 This is space the hammer CCH 197 00:07:21,990 --> 00:07:24,779 dumped to a bahnhof plant and blown, 198 00:07:24,780 --> 00:07:27,059 and at each point in space, 199 00:07:27,060 --> 00:07:29,579 that's a virtual or internal 200 00:07:29,580 --> 00:07:32,189 plane attached to each point in space. 201 00:07:32,190 --> 00:07:34,679 So far, five by five. 202 00:07:34,680 --> 00:07:36,939 My point is dying, but for five by 203 00:07:36,940 --> 00:07:40,049 five points, I've drawn these spheres. 204 00:07:40,050 --> 00:07:42,029 Not not spheres, actually, that whole 205 00:07:42,030 --> 00:07:44,369 planes and 206 00:07:44,370 --> 00:07:45,869 they have a rotational symmetry. 207 00:07:45,870 --> 00:07:47,999 I can rotate the plane around the 208 00:07:48,000 --> 00:07:49,739 origin, so let's do that. 209 00:07:49,740 --> 00:07:51,569 So now I hope everybody can see that 210 00:07:51,570 --> 00:07:54,329 these guys are rotating around the origin 211 00:07:54,330 --> 00:07:56,319 and rotating. 212 00:07:56,320 --> 00:07:57,539 Yeah, yeah. You got it. 213 00:07:57,540 --> 00:07:59,279 Get an idea, at least the people in the 214 00:07:59,280 --> 00:08:00,280 front row. 215 00:08:02,520 --> 00:08:04,409 But the important thing is, so now 216 00:08:04,410 --> 00:08:06,509 they're all rotating in the same way, 217 00:08:06,510 --> 00:08:08,160 they are all rotating in parallel. 218 00:08:09,630 --> 00:08:11,459 But you can rotate them independently. 219 00:08:11,460 --> 00:08:13,469 So now this starts, then the others come 220 00:08:13,470 --> 00:08:15,929 on. And so you see that 221 00:08:15,930 --> 00:08:18,059 each one is rotating 222 00:08:18,060 --> 00:08:19,149 separately from the other. 223 00:08:19,150 --> 00:08:21,359 So this movie that you see here 224 00:08:21,360 --> 00:08:23,579 is actually a depiction 225 00:08:23,580 --> 00:08:25,709 of an electromagnetic wave 226 00:08:25,710 --> 00:08:28,019 traveling here from once this 227 00:08:30,540 --> 00:08:32,189 southwest to northeast. 228 00:08:32,190 --> 00:08:33,190 So here it goes again. 229 00:08:35,610 --> 00:08:36,869 OK. 230 00:08:36,870 --> 00:08:39,209 And I claim, and I 231 00:08:39,210 --> 00:08:41,609 have to ask you to believe 232 00:08:41,610 --> 00:08:44,309 this. I cannot explain this further that 233 00:08:44,310 --> 00:08:46,499 electromagnetism is nothing 234 00:08:46,500 --> 00:08:48,899 but the description of these rotations. 235 00:08:48,900 --> 00:08:50,609 So you have a description of these 236 00:08:50,610 --> 00:08:52,209 rotations. 237 00:08:52,210 --> 00:08:54,419 I'm talking in an equivalent 238 00:08:54,420 --> 00:08:56,759 way about electromagnetism. 239 00:08:56,760 --> 00:08:58,889 This is actually a representation of 240 00:08:58,890 --> 00:09:00,839 Maxwell's equations. 241 00:09:00,840 --> 00:09:03,179 If you happen to know what those are. 242 00:09:03,180 --> 00:09:05,099 So in particular, there is some somewhere 243 00:09:05,100 --> 00:09:07,109 in these rotation. That's the Coulomb law 244 00:09:07,110 --> 00:09:08,669 that describes the force between two 245 00:09:08,670 --> 00:09:09,809 charges. 246 00:09:09,810 --> 00:09:12,119 But I'm claiming 247 00:09:12,120 --> 00:09:14,309 this is contains all the information 248 00:09:14,310 --> 00:09:16,529 about the electromagnetism, how all these 249 00:09:16,530 --> 00:09:17,530 planes rotate. 250 00:09:20,770 --> 00:09:22,869 OK. So and and the point is 251 00:09:22,870 --> 00:09:25,149 not only electromagnetism is about 252 00:09:25,150 --> 00:09:26,619 of this type. 253 00:09:26,620 --> 00:09:28,689 So electromagnetism is a rotation 254 00:09:28,690 --> 00:09:30,099 of a plane. Here you see the plane 255 00:09:30,100 --> 00:09:32,349 rotating, but also the weak 256 00:09:32,350 --> 00:09:34,609 force. Remember Decay, 257 00:09:34,610 --> 00:09:37,089 K, W and Z bosons? 258 00:09:37,090 --> 00:09:39,279 This is also about rotations, but those 259 00:09:39,280 --> 00:09:41,379 this force is not about rotations 260 00:09:41,380 --> 00:09:42,549 of a plane. 261 00:09:42,550 --> 00:09:44,619 This rod rotations in a 262 00:09:44,620 --> 00:09:45,519 three dimensional space. 263 00:09:45,520 --> 00:09:47,319 So if you like of a sphere, so this 264 00:09:47,320 --> 00:09:49,299 sphere here is rotating about different 265 00:09:49,300 --> 00:09:51,669 axes and that's and coating 266 00:09:51,670 --> 00:09:52,670 the weak force. 267 00:09:53,710 --> 00:09:55,179 So weak force. 268 00:09:55,180 --> 00:09:57,459 So technically, it's not the this 269 00:09:57,460 --> 00:09:59,409 group that rotation was assumed to. 270 00:10:01,000 --> 00:10:03,129 There's also the strong force that is 271 00:10:03,130 --> 00:10:04,839 about rotations in a complex, three 272 00:10:04,840 --> 00:10:06,099 dimensional space, and I don't have a 273 00:10:06,100 --> 00:10:08,650 better picture of this than hyperspace. 274 00:10:09,760 --> 00:10:11,919 But the principle the mathematics is the 275 00:10:11,920 --> 00:10:13,359 same is just high dimensional. 276 00:10:15,010 --> 00:10:17,409 OK, so that is I claim 277 00:10:17,410 --> 00:10:19,659 these these are all the forces 278 00:10:19,660 --> 00:10:20,769 in the universe. 279 00:10:20,770 --> 00:10:23,109 Maybe, except gravity are just 280 00:10:23,110 --> 00:10:25,419 rotations of some sort of internal spaces 281 00:10:25,420 --> 00:10:27,699 that are attached to each point in space. 282 00:10:27,700 --> 00:10:28,869 OK. 283 00:10:28,870 --> 00:10:30,489 These are the forces. Now comes the Higgs 284 00:10:30,490 --> 00:10:32,739 effect. So what so you told you a Higgs 285 00:10:32,740 --> 00:10:35,169 particle Nobel Prize 2013? 286 00:10:35,170 --> 00:10:38,229 I explain to you what the Higgs effect is 287 00:10:38,230 --> 00:10:39,309 very simple. 288 00:10:39,310 --> 00:10:41,199 In addition to the plane, there's a 289 00:10:41,200 --> 00:10:43,719 little blue ball in the plane, 290 00:10:43,720 --> 00:10:46,089 and the Higgs field 291 00:10:46,090 --> 00:10:48,399 just tells you where in the plane 292 00:10:48,400 --> 00:10:49,869 the ball is. So right now, it's in the 293 00:10:49,870 --> 00:10:51,819 origin, right? 294 00:10:51,820 --> 00:10:52,899 But I can move in principle. 295 00:10:52,900 --> 00:10:54,459 I can move the ball around to any other 296 00:10:54,460 --> 00:10:55,749 point in the plane. 297 00:10:55,750 --> 00:10:57,849 And the notion where the ball is that 298 00:10:57,850 --> 00:11:00,069 is the Higgs field in the same 299 00:11:00,070 --> 00:11:02,079 spirit as the rotation of the plane is 300 00:11:02,080 --> 00:11:03,080 electromagnetism. 301 00:11:04,820 --> 00:11:07,069 And now we add something to this plane, 302 00:11:07,070 --> 00:11:09,679 we add a potential energy, so kind of 303 00:11:09,680 --> 00:11:11,179 landscape, so let's turn that on. 304 00:11:13,640 --> 00:11:15,769 So this now looks a bit like the 305 00:11:15,770 --> 00:11:17,899 bottom of a champagne bottle. 306 00:11:17,900 --> 00:11:20,059 So I've added some potential LNG, 307 00:11:20,060 --> 00:11:22,669 but this is still rotational asymmetric. 308 00:11:24,350 --> 00:11:26,539 So now rotational symmetry is still 309 00:11:26,540 --> 00:11:28,879 intact. Now you have these champagne 310 00:11:28,880 --> 00:11:31,039 bottles with a blue ball in 311 00:11:31,040 --> 00:11:32,749 the origin, and this thing is still 312 00:11:32,750 --> 00:11:33,739 protection symmetric. 313 00:11:33,740 --> 00:11:36,079 The wave goes 314 00:11:36,080 --> 00:11:37,429 through Hamburg. 315 00:11:39,630 --> 00:11:40,630 Hello. 316 00:11:43,680 --> 00:11:46,379 OK, but of course, the ball at the tip 317 00:11:46,380 --> 00:11:47,759 of the champagne bottle is not the 318 00:11:47,760 --> 00:11:50,099 minimal energy configuration 319 00:11:50,100 --> 00:11:52,229 the ball wants to be further down. 320 00:11:52,230 --> 00:11:53,819 You can gain energy by bringing the ball 321 00:11:53,820 --> 00:11:54,919 down. 322 00:11:54,920 --> 00:11:56,399 So let's do that. 323 00:11:56,400 --> 00:11:58,619 What now you see the balls 324 00:11:58,620 --> 00:11:59,969 at the bottom? 325 00:11:59,970 --> 00:12:01,919 So and of course, there's more than one 326 00:12:01,920 --> 00:12:03,299 possibility to put the ball at the 327 00:12:03,300 --> 00:12:05,249 bottom. There's a whole ring of possible 328 00:12:05,250 --> 00:12:07,259 places where the ball can lie and a 329 00:12:07,260 --> 00:12:09,389 minimal energy configuration. 330 00:12:09,390 --> 00:12:11,459 And each one of them, each 331 00:12:11,460 --> 00:12:13,769 choice for possession 332 00:12:13,770 --> 00:12:16,049 of the ball on the bottom 333 00:12:16,050 --> 00:12:17,429 breaks the rotational symmetry. 334 00:12:17,430 --> 00:12:18,959 Wherever I place the ball, the symmetry 335 00:12:18,960 --> 00:12:19,949 is broken. 336 00:12:19,950 --> 00:12:22,349 So now if I rotate these planes 337 00:12:22,350 --> 00:12:24,539 with the ball, as this happens 338 00:12:24,540 --> 00:12:26,999 here, I have to drag the ball around 339 00:12:27,000 --> 00:12:29,099 and that costs energy and 340 00:12:29,100 --> 00:12:30,100 this energy. 341 00:12:32,430 --> 00:12:34,559 This turns out to 342 00:12:34,560 --> 00:12:36,419 be the mass that is given, so the 343 00:12:36,420 --> 00:12:37,769 symmetry is broken. 344 00:12:37,770 --> 00:12:39,239 And this is how mass is created. 345 00:12:39,240 --> 00:12:41,309 The mass is actually the energy it 346 00:12:41,310 --> 00:12:43,829 costs to drag the ball 347 00:12:43,830 --> 00:12:46,229 around when the electromagnetic wave 348 00:12:46,230 --> 00:12:48,749 goes through this configuration 349 00:12:48,750 --> 00:12:50,459 with the broken symmetry, and that is the 350 00:12:50,460 --> 00:12:52,199 Higgs effect. This is how the Higgs 351 00:12:52,200 --> 00:12:53,909 effect gives mass to elementary 352 00:12:53,910 --> 00:12:54,910 particles. 353 00:12:56,480 --> 00:12:58,729 And so, OK, so 354 00:12:58,730 --> 00:12:59,809 when I said this happens in 355 00:12:59,810 --> 00:13:01,399 electromagnetism, this is actually not 356 00:13:01,400 --> 00:13:02,539 true, I lie to you 357 00:13:03,980 --> 00:13:06,049 in electromagnetism, the symmetry is 358 00:13:06,050 --> 00:13:08,299 not broken and the photon is 359 00:13:08,300 --> 00:13:10,279 mass remains massless. 360 00:13:10,280 --> 00:13:12,529 That's good because otherwise it couldn't 361 00:13:12,530 --> 00:13:14,119 travel long distance. 362 00:13:14,120 --> 00:13:15,769 You couldn't see me of the photon where 363 00:13:15,770 --> 00:13:18,379 massive it would decay before it reaches 364 00:13:18,380 --> 00:13:20,149 the photon that comes from me or from the 365 00:13:20,150 --> 00:13:22,639 screen would decay and would not be there 366 00:13:22,640 --> 00:13:24,199 if it would be massive, but it's massive 367 00:13:24,200 --> 00:13:26,029 so you can see the screen. 368 00:13:26,030 --> 00:13:28,159 But the Higgs effect takes place 369 00:13:28,160 --> 00:13:29,279 for the weak interaction. 370 00:13:29,280 --> 00:13:31,699 Remember, that was the one with the 371 00:13:31,700 --> 00:13:33,769 rotating ball, but then with the ball, 372 00:13:33,770 --> 00:13:35,899 I couldn't draw the the potential, so I 373 00:13:35,900 --> 00:13:38,659 chose to use this representation. 374 00:13:38,660 --> 00:13:39,660 But it happens for the 375 00:13:41,180 --> 00:13:42,259 for the weak interaction. 376 00:13:42,260 --> 00:13:44,539 And this Higgs effect makes these 377 00:13:44,540 --> 00:13:46,909 Z and W bosons that 378 00:13:46,910 --> 00:13:49,009 mediate this force. 379 00:13:49,010 --> 00:13:51,319 It gives them a mass of roughly 100 380 00:13:51,320 --> 00:13:52,849 gig electron volts could get electron 381 00:13:52,850 --> 00:13:54,079 volts or electron volts. 382 00:13:54,080 --> 00:13:56,269 Is the energy unit the particle physics 383 00:13:56,270 --> 00:13:57,949 physicists use? That's very convenient, 384 00:13:57,950 --> 00:13:59,269 so this is an important number. 385 00:13:59,270 --> 00:14:01,190 Remember this one hundred GeV? 386 00:14:03,680 --> 00:14:05,869 OK, and this mass 387 00:14:05,870 --> 00:14:07,939 corresponds to the distance that the 388 00:14:07,940 --> 00:14:09,199 ball has from the center. 389 00:14:09,200 --> 00:14:11,389 So. So that's kind of the radius of 390 00:14:11,390 --> 00:14:13,219 the of the motion of the ball that I have 391 00:14:13,220 --> 00:14:15,499 to drag around. The further it's out 392 00:14:15,500 --> 00:14:17,719 there, the more difficult 393 00:14:17,720 --> 00:14:19,190 it gets to direct the ball around. 394 00:14:21,290 --> 00:14:23,689 OK, so so that was the Higgs effect 395 00:14:23,690 --> 00:14:26,059 and gauge interaction, so 396 00:14:26,060 --> 00:14:27,439 such interactions are called gauge 397 00:14:27,440 --> 00:14:28,549 interactions. 398 00:14:28,550 --> 00:14:30,769 German speakers call them, I 399 00:14:30,770 --> 00:14:31,770 call. 400 00:14:32,760 --> 00:14:33,760 OK. 401 00:14:35,280 --> 00:14:36,280 OK, so now 402 00:14:37,350 --> 00:14:38,639 for something completely different. 403 00:14:38,640 --> 00:14:40,799 That was my first explanation, this is 404 00:14:40,800 --> 00:14:42,659 how electromagnetism and his friends 405 00:14:42,660 --> 00:14:44,969 work. Now comes a different concept 406 00:14:44,970 --> 00:14:47,189 that's called ring normalization. 407 00:14:47,190 --> 00:14:49,589 So now I'm 408 00:14:49,590 --> 00:14:51,539 for second. I'm back to the old picture. 409 00:14:51,540 --> 00:14:52,919 This is supposed to be an electron and 410 00:14:52,920 --> 00:14:54,059 this is supposed to be 411 00:14:56,550 --> 00:14:58,769 the antiparticle of an electron positron. 412 00:14:58,770 --> 00:15:01,199 This is just like the electron 413 00:15:01,200 --> 00:15:02,759 just with positive charge instead of 414 00:15:02,760 --> 00:15:04,139 negative charge. This has nothing to do 415 00:15:04,140 --> 00:15:05,099 with the super fast. 416 00:15:05,100 --> 00:15:07,239 This is all standard model 417 00:15:07,240 --> 00:15:09,329 physics and the 418 00:15:09,330 --> 00:15:10,379 wiggly lines have drawn. 419 00:15:10,380 --> 00:15:11,519 Here is the cooling field. 420 00:15:11,520 --> 00:15:13,739 That's the electromagnetic field 421 00:15:13,740 --> 00:15:16,199 that drags the 422 00:15:16,200 --> 00:15:18,359 this violet ball towards the Red 423 00:15:18,360 --> 00:15:20,759 Bull. And everybody learned 424 00:15:20,760 --> 00:15:23,639 in school that this force 425 00:15:23,640 --> 00:15:25,739 that the force of 426 00:15:25,740 --> 00:15:28,139 attraction between the balls 427 00:15:28,140 --> 00:15:29,909 is proportional to the charge of the 428 00:15:29,910 --> 00:15:32,459 electron and it scales 429 00:15:32,460 --> 00:15:33,869 inversely with the square of the 430 00:15:33,870 --> 00:15:35,699 distance. That's cool, MS Law. 431 00:15:35,700 --> 00:15:37,019 Everybody should have learned this in 432 00:15:37,020 --> 00:15:39,599 high school at some point, hopefully. 433 00:15:39,600 --> 00:15:40,499 OK, cool. 434 00:15:40,500 --> 00:15:42,330 I'm sorry this everybody knows. 435 00:15:47,280 --> 00:15:48,360 OK, so now 436 00:15:49,500 --> 00:15:51,719 this this picture, this was classical 437 00:15:51,720 --> 00:15:53,339 physics. This is the first to learn in 438 00:15:53,340 --> 00:15:55,649 school, but the world is a quantum world 439 00:15:55,650 --> 00:15:56,940 and it's more complicated. 440 00:15:58,650 --> 00:16:01,229 The upshot of of of quantum mechanics is 441 00:16:01,230 --> 00:16:03,539 that the charge of the electron actually 442 00:16:03,540 --> 00:16:05,729 depends on the distance at 443 00:16:05,730 --> 00:16:07,019 which you look at it. 444 00:16:07,020 --> 00:16:08,429 And this comes about as follows. 445 00:16:09,660 --> 00:16:11,939 So quantum mechanics says the vacuum 446 00:16:11,940 --> 00:16:13,609 is not empty. 447 00:16:13,610 --> 00:16:16,169 Oh, not a lot of bottle 448 00:16:16,170 --> 00:16:17,879 for some. 449 00:16:17,880 --> 00:16:19,289 OK. You fell asleep. 450 00:16:19,290 --> 00:16:20,290 No problem. 451 00:16:21,890 --> 00:16:23,879 You were OK. 452 00:16:25,470 --> 00:16:26,470 Everything OK, 453 00:16:27,760 --> 00:16:29,939 OK. Back to quantum physics. 454 00:16:29,940 --> 00:16:32,369 Quantum physics says the vacuum 455 00:16:32,370 --> 00:16:34,499 is full of virtual pairs 456 00:16:34,500 --> 00:16:36,599 of particle particles 457 00:16:36,600 --> 00:16:38,039 and the antibiotics. They pop out of 458 00:16:38,040 --> 00:16:39,359 nothing and annihilate again. 459 00:16:39,360 --> 00:16:41,279 So I've drawn a couple of those here. 460 00:16:41,280 --> 00:16:42,629 You see the original electron, the 461 00:16:42,630 --> 00:16:44,489 original positron. But there are a couple 462 00:16:44,490 --> 00:16:46,889 of other electron positron pairs 463 00:16:46,890 --> 00:16:49,229 that have popped out of the vacuum for a 464 00:16:49,230 --> 00:16:50,230 split second. 465 00:16:51,450 --> 00:16:53,759 But these particles are also charged. 466 00:16:53,760 --> 00:16:55,919 Posit the the red 467 00:16:55,920 --> 00:16:58,109 one is positive and the the the 468 00:16:58,110 --> 00:17:00,059 purple one is negative. 469 00:17:00,060 --> 00:17:02,219 The other way round red, negative, 470 00:17:02,220 --> 00:17:03,839 purple positive. 471 00:17:03,840 --> 00:17:06,029 And they also see the electromagnetic 472 00:17:06,030 --> 00:17:08,098 field of this electron. 473 00:17:08,099 --> 00:17:10,169 So the purple one likes to 474 00:17:10,170 --> 00:17:13,019 go towards the Red Bowl, and the Red Bull 475 00:17:13,020 --> 00:17:15,149 likes to go away from it. 476 00:17:15,150 --> 00:17:17,338 So, so, so they align a little bit 477 00:17:17,339 --> 00:17:19,469 in this field. You see that 478 00:17:19,470 --> 00:17:21,179 the purple one's always closer to the red 479 00:17:21,180 --> 00:17:23,608 ball in the virtual positron 480 00:17:23,609 --> 00:17:26,489 electron pair, then the electron. 481 00:17:26,490 --> 00:17:28,859 So that causes 482 00:17:28,860 --> 00:17:30,509 something like a polarization of the 483 00:17:30,510 --> 00:17:33,149 vacuum and that yields 484 00:17:33,150 --> 00:17:36,389 shielding effect. So now this 485 00:17:36,390 --> 00:17:38,609 positron that was supposed to see 486 00:17:38,610 --> 00:17:40,739 the electric field of this electron not 487 00:17:40,740 --> 00:17:42,089 only sees the electric field of this 488 00:17:42,090 --> 00:17:44,129 electron that I've drawn here, but it 489 00:17:44,130 --> 00:17:46,469 sees also the electric field of all 490 00:17:46,470 --> 00:17:48,959 these other virtual particles and because 491 00:17:48,960 --> 00:17:51,959 they are aligned in the original field. 492 00:17:51,960 --> 00:17:54,329 Turns out, the field at this particle 493 00:17:54,330 --> 00:17:56,039 size is actually a little bit weaker 494 00:17:57,060 --> 00:17:59,309 because it's shielded by these 495 00:17:59,310 --> 00:18:01,379 other pairs, and 496 00:18:01,380 --> 00:18:03,899 this shielding effect is stronger. 497 00:18:03,900 --> 00:18:06,089 The stronger the the first field is 498 00:18:06,090 --> 00:18:08,429 because the stronger the so 499 00:18:08,430 --> 00:18:11,009 stronger because you are closer. 500 00:18:11,010 --> 00:18:13,349 So when you're closer than the alignment 501 00:18:13,350 --> 00:18:15,149 is even stronger and the shielding effect 502 00:18:15,150 --> 00:18:17,759 is even stronger, and you can 503 00:18:17,760 --> 00:18:19,919 subsume this by saying 504 00:18:19,920 --> 00:18:22,259 actually, so I total all 505 00:18:22,260 --> 00:18:24,359 these that charge and the shielding into 506 00:18:24,360 --> 00:18:26,309 a new charge called the re normalized 507 00:18:26,310 --> 00:18:28,529 charge. And that is then 508 00:18:28,530 --> 00:18:30,239 the charge that depends on the distance. 509 00:18:30,240 --> 00:18:32,519 Ah, so now the electric 510 00:18:32,520 --> 00:18:35,219 field e is proportional 511 00:18:35,220 --> 00:18:37,919 well at distance AH is proportional 512 00:18:37,920 --> 00:18:40,139 to the charge corresponding 513 00:18:40,140 --> 00:18:41,219 to the particular distance. 514 00:18:41,220 --> 00:18:43,139 Here are is this or some here to here. 515 00:18:43,140 --> 00:18:44,879 Divide it by all squared. 516 00:18:44,880 --> 00:18:46,859 That's the upshot of your normalization. 517 00:18:46,860 --> 00:18:48,569 That's a quantum version of the rule of 518 00:18:48,570 --> 00:18:49,570 law. 519 00:18:49,980 --> 00:18:51,869 So now how does Q of our look like 520 00:18:53,160 --> 00:18:55,169 so so that that's called running 521 00:18:55,170 --> 00:18:57,329 couplings because the well, 522 00:18:57,330 --> 00:18:58,349 the charge is 523 00:18:59,580 --> 00:19:00,479 special. 524 00:19:00,480 --> 00:19:02,549 Well, I mean, it's one example of 525 00:19:02,550 --> 00:19:04,679 coupling and it's 526 00:19:04,680 --> 00:19:06,239 running because it depends on the 527 00:19:06,240 --> 00:19:07,679 distance. 528 00:19:07,680 --> 00:19:09,749 And a similar effect applies not only 529 00:19:09,750 --> 00:19:11,819 to the charge of particles, but also 530 00:19:11,820 --> 00:19:14,069 for other properties of the particles, 531 00:19:14,070 --> 00:19:15,839 for example of the mass, also the mass of 532 00:19:15,840 --> 00:19:18,359 a particle like five and 11 533 00:19:18,360 --> 00:19:20,369 K.V. for an electron. 534 00:19:20,370 --> 00:19:22,379 That's not the full truth that depends on 535 00:19:22,380 --> 00:19:24,749 the distance, the distance 536 00:19:24,750 --> 00:19:27,449 at which I measure the mass 537 00:19:27,450 --> 00:19:29,699 and for almost all properties. 538 00:19:29,700 --> 00:19:31,299 This dependance of. 539 00:19:31,300 --> 00:19:33,169 Are logarithmic. 540 00:19:33,170 --> 00:19:35,749 So there is a coefficient called beta, 541 00:19:35,750 --> 00:19:37,849 the so-called beta function times 542 00:19:37,850 --> 00:19:39,739 the logarithm of our logarithm, as you 543 00:19:39,740 --> 00:19:42,049 know, the function that grows very slowly 544 00:19:42,050 --> 00:19:44,479 with R and this 545 00:19:44,480 --> 00:19:46,759 coefficient theta depends 546 00:19:46,760 --> 00:19:49,189 on particular types of of 547 00:19:49,190 --> 00:19:51,649 the particles that are participating 548 00:19:51,650 --> 00:19:52,909 in this shielding. So you have to 549 00:19:54,110 --> 00:19:56,249 you can calculate this actually and 550 00:19:56,250 --> 00:19:58,309 depends on all the types of particles 551 00:19:58,310 --> 00:19:59,990 that can pop up from the vacuum. 552 00:20:01,340 --> 00:20:03,409 And also another property of 553 00:20:03,410 --> 00:20:05,429 a particle is the shape. 554 00:20:05,430 --> 00:20:07,250 Remember, the champagne bottle 555 00:20:08,420 --> 00:20:11,119 are the shape of the potential, 556 00:20:11,120 --> 00:20:13,429 and that happens to depend 557 00:20:13,430 --> 00:20:15,739 not logarithmic Li like the charge 558 00:20:15,740 --> 00:20:18,259 or the mass, but it depends quadratic 559 00:20:18,260 --> 00:20:19,939 li on the distance. So it goes more like 560 00:20:19,940 --> 00:20:22,159 some coefficient times are squared 561 00:20:22,160 --> 00:20:25,099 and our squared is a function that 562 00:20:25,100 --> 00:20:27,109 is much more sensitive to our than the 563 00:20:27,110 --> 00:20:28,069 logarithm you change. 564 00:20:28,070 --> 00:20:30,139 Our little bit logarithm stays mostly 565 00:20:30,140 --> 00:20:31,069 the same. 566 00:20:31,070 --> 00:20:33,079 We change our little bit, but the square 567 00:20:33,080 --> 00:20:34,970 of that change is actually quite a bit 568 00:20:36,710 --> 00:20:39,379 so. And because the mass 569 00:20:39,380 --> 00:20:41,569 of the W inset bosons, remember they 570 00:20:41,570 --> 00:20:43,459 came from the ball that it was not in the 571 00:20:43,460 --> 00:20:45,890 center, but somewhere in this potential. 572 00:20:47,210 --> 00:20:49,309 So the result is that the 573 00:20:49,310 --> 00:20:51,499 mass of these particles is very sensitive 574 00:20:51,500 --> 00:20:53,989 to the distance at which I measure them. 575 00:20:53,990 --> 00:20:56,209 And and for particle physics 576 00:20:56,210 --> 00:20:58,279 units, one 577 00:20:58,280 --> 00:20:59,869 is actually quite a small mass. 578 00:21:01,580 --> 00:21:03,799 And if it were in fact 579 00:21:03,800 --> 00:21:05,209 quite dramatically sensitive to the 580 00:21:05,210 --> 00:21:07,519 distance, it's very unnatural 581 00:21:07,520 --> 00:21:09,229 to be so small. 582 00:21:09,230 --> 00:21:11,299 Based on order of magnitude estimate, 583 00:21:11,300 --> 00:21:13,489 you would actually expected to be 584 00:21:13,490 --> 00:21:15,529 17 orders of magnitude bigger. 585 00:21:15,530 --> 00:21:17,149 So the natural size would be more the 586 00:21:17,150 --> 00:21:19,099 Planck. Such plans to have 10 to the 19 587 00:21:19,100 --> 00:21:21,439 GB, rather than the 10 to the two G.V. 588 00:21:21,440 --> 00:21:23,749 that it actually is as 589 00:21:23,750 --> 00:21:24,919 a question. 590 00:21:24,920 --> 00:21:25,920 When you say the mass. 591 00:21:29,860 --> 00:21:32,649 The point is it cannot be quadratic 592 00:21:32,650 --> 00:21:34,809 because it would be a good one, just one 593 00:21:34,810 --> 00:21:36,399 distance, and if you change this in a 594 00:21:36,400 --> 00:21:37,539 little bit, it would be completely 595 00:21:37,540 --> 00:21:38,439 different. 596 00:21:38,440 --> 00:21:39,670 And that's not what we observe. 597 00:21:40,990 --> 00:21:41,990 So 598 00:21:43,120 --> 00:21:45,279 this smallness of of this 599 00:21:45,280 --> 00:21:46,869 mass is not natural. 600 00:21:46,870 --> 00:21:48,249 We would expect it to be much, much 601 00:21:48,250 --> 00:21:50,379 bigger based on 602 00:21:50,380 --> 00:21:51,519 this type of argument. 603 00:21:52,660 --> 00:21:54,819 So we have to explain why 604 00:21:54,820 --> 00:21:57,129 nature can maintain the small mass 605 00:21:57,130 --> 00:21:58,270 of one hundred easy 606 00:21:59,440 --> 00:22:01,059 and simple. And that's the naturalness 607 00:22:01,060 --> 00:22:03,249 problem. Explain how the mass can 608 00:22:03,250 --> 00:22:05,140 be. Hundreds of small 609 00:22:06,190 --> 00:22:08,379 and supersymmetry provides 610 00:22:08,380 --> 00:22:10,389 a solution to this problem. 611 00:22:10,390 --> 00:22:11,829 How does it work? 612 00:22:11,830 --> 00:22:14,379 Well, it works because 613 00:22:14,380 --> 00:22:16,599 the coefficient there was this alpha 614 00:22:16,600 --> 00:22:17,600 coefficient. 615 00:22:19,210 --> 00:22:21,489 It was this number in front that 616 00:22:21,490 --> 00:22:23,649 says, how was 617 00:22:23,650 --> 00:22:25,359 the coefficient of this r squared 618 00:22:26,500 --> 00:22:28,239 in supersymmetric theories? 619 00:22:29,560 --> 00:22:31,839 The original standard model particles 620 00:22:31,840 --> 00:22:33,789 and their super partners contribute 621 00:22:33,790 --> 00:22:35,739 exactly the same amount, but with 622 00:22:35,740 --> 00:22:38,649 opposite signs to this alpha. 623 00:22:38,650 --> 00:22:40,719 So if as if I'm not only 624 00:22:40,720 --> 00:22:42,999 electrons and positrons popping 625 00:22:43,000 --> 00:22:44,439 out of the vacuum, but as well so 626 00:22:44,440 --> 00:22:46,869 electrons and positrons 627 00:22:46,870 --> 00:22:49,149 are that effect cancels and 628 00:22:49,150 --> 00:22:50,799 there's a zero in front of this r 629 00:22:50,800 --> 00:22:51,800 squared. 630 00:22:52,390 --> 00:22:55,299 So this quadratic running 631 00:22:55,300 --> 00:22:58,299 of the mass of the W and Z bosons 632 00:22:58,300 --> 00:23:00,579 goes away for exactly 633 00:23:00,580 --> 00:23:02,499 supersymmetric theories because in 634 00:23:02,500 --> 00:23:04,419 supersymmetry, the effect of the 635 00:23:04,420 --> 00:23:07,209 different types cancel. 636 00:23:07,210 --> 00:23:10,689 So that would be an explanation 637 00:23:10,690 --> 00:23:12,849 of the naturalness and well of the 638 00:23:12,850 --> 00:23:15,519 smallness of the size and the naturalness 639 00:23:15,520 --> 00:23:17,829 would be saved if this if 640 00:23:17,830 --> 00:23:19,599 nature would have, in addition to 641 00:23:19,600 --> 00:23:20,889 electrons and positrons, their 642 00:23:20,890 --> 00:23:21,890 superpowers. 643 00:23:23,290 --> 00:23:25,359 Well, that that would be too 644 00:23:25,360 --> 00:23:27,249 nice to be true because 645 00:23:28,690 --> 00:23:30,969 supersymmetry predicts that besides 646 00:23:30,970 --> 00:23:31,970 the spin 647 00:23:33,340 --> 00:23:34,809 on the other properties of the partner 648 00:23:34,810 --> 00:23:36,939 particles, so the selections for the 649 00:23:36,940 --> 00:23:37,940 electrons 650 00:23:39,570 --> 00:23:40,629 are actually the same. 651 00:23:40,630 --> 00:23:42,789 So in particular, I would predict 652 00:23:42,790 --> 00:23:44,889 that the electron also has the 653 00:23:44,890 --> 00:23:47,349 same mass as the Electron 511 654 00:23:47,350 --> 00:23:48,350 K.V.. 655 00:23:49,570 --> 00:23:51,729 But of course, I told you nobody has 656 00:23:51,730 --> 00:23:54,129 seen this supersymmetric partner particle 657 00:23:54,130 --> 00:23:55,839 in particular. We would have known if 658 00:23:55,840 --> 00:23:57,969 there were a boson, so that could 659 00:23:57,970 --> 00:23:59,799 be a part in the particle at five hundred 660 00:23:59,800 --> 00:24:01,519 twelve. Sorry, I'm on the same question. 661 00:24:01,520 --> 00:24:02,619 11. Now it's Typhon. 662 00:24:02,620 --> 00:24:04,599 11 This, too, is wrong. 663 00:24:04,600 --> 00:24:06,519 So if there would be another particle 664 00:24:06,520 --> 00:24:08,559 with the same mass as the electron, I 665 00:24:08,560 --> 00:24:10,659 mean, we produce electrons all 666 00:24:10,660 --> 00:24:12,039 the all the time, and we have never 667 00:24:12,040 --> 00:24:13,459 produced any of these foreign particles. 668 00:24:13,460 --> 00:24:15,219 So so that that cannot be true. 669 00:24:15,220 --> 00:24:17,229 I mean, supersymmetry that predicts the 670 00:24:17,230 --> 00:24:18,699 partner particles have the same mass must 671 00:24:18,700 --> 00:24:19,700 be wrong. 672 00:24:20,950 --> 00:24:23,139 And the way out is there's 673 00:24:23,140 --> 00:24:24,339 also a Higgs effect. 674 00:24:24,340 --> 00:24:26,139 So the symmetry breaking effect from the 675 00:24:26,140 --> 00:24:28,119 ball rolling away from the center 676 00:24:29,380 --> 00:24:31,869 that breaks supersymmetry. 677 00:24:31,870 --> 00:24:33,759 So supersymmetry is also a broken 678 00:24:33,760 --> 00:24:35,829 symmetry like this rotational 679 00:24:35,830 --> 00:24:37,449 symmetry in nature. 680 00:24:37,450 --> 00:24:39,549 But we have to do this in a way to 681 00:24:39,550 --> 00:24:41,709 preserve this naturalness 682 00:24:41,710 --> 00:24:43,179 that the supersymmetry brings. 683 00:24:44,290 --> 00:24:45,460 So how does that work? 684 00:24:46,700 --> 00:24:48,999 So, so there's some way to break Susy, 685 00:24:49,000 --> 00:24:50,140 like with the ball 686 00:24:51,370 --> 00:24:53,439 and then the super partners of of all the 687 00:24:53,440 --> 00:24:55,509 known particles can have larger mass 688 00:24:55,510 --> 00:24:57,609 than the known particles, and 689 00:24:57,610 --> 00:24:59,079 then the quadratic running is back 690 00:24:59,080 --> 00:25:00,609 because the canceling is not exact 691 00:25:00,610 --> 00:25:01,610 anymore, 692 00:25:02,770 --> 00:25:04,899 but only up to about the 693 00:25:04,900 --> 00:25:06,049 mass of the super partner. 694 00:25:06,050 --> 00:25:08,709 So up from that mass on 695 00:25:08,710 --> 00:25:10,839 there again, particles 696 00:25:10,840 --> 00:25:12,939 and super PACs, and then the cancelation 697 00:25:12,940 --> 00:25:13,940 kicks in again. 698 00:25:14,920 --> 00:25:15,819 Is that clear? 699 00:25:15,820 --> 00:25:18,279 So for masses below 700 00:25:18,280 --> 00:25:20,229 the mass of super fast, the super planets 701 00:25:20,230 --> 00:25:21,789 are invisible and there is quadratic 702 00:25:21,790 --> 00:25:23,859 running, but for higher energies 703 00:25:23,860 --> 00:25:25,509 or for higher masses where the super 704 00:25:25,510 --> 00:25:26,510 partners are, 705 00:25:27,730 --> 00:25:29,949 the cancelation effectively works again. 706 00:25:31,060 --> 00:25:32,979 So we would expect that the running 707 00:25:32,980 --> 00:25:34,959 happens. There is quadratic running, but 708 00:25:34,960 --> 00:25:36,729 only up to the mass. 709 00:25:37,830 --> 00:25:40,199 Of the super partners, 710 00:25:40,200 --> 00:25:42,389 and that means since the mass that we 711 00:25:42,390 --> 00:25:44,849 observe of the billions that bulldozers 712 00:25:44,850 --> 00:25:47,189 have 100 GV, if this 713 00:25:47,190 --> 00:25:49,079 explanation of natural naturalist works, 714 00:25:49,080 --> 00:25:50,549 then this would suggest that super 715 00:25:50,550 --> 00:25:52,859 partners also have masses 716 00:25:52,860 --> 00:25:54,520 in this range of 100 G.V.. 717 00:25:57,060 --> 00:25:58,409 OK, that was the point with the 718 00:25:58,410 --> 00:26:00,359 naturalness that was actually the 719 00:26:00,360 --> 00:26:02,489 strongest point for supersymmetry. 720 00:26:02,490 --> 00:26:04,049 There's another point called unification 721 00:26:04,050 --> 00:26:05,609 of cage interaction, so I explained what 722 00:26:05,610 --> 00:26:07,259 gauge interactions are gauge interactions 723 00:26:07,260 --> 00:26:09,989 are these things with rotations? 724 00:26:09,990 --> 00:26:11,789 And I told you are three in nature. 725 00:26:11,790 --> 00:26:13,349 There is the electromagnetic force, which 726 00:26:13,350 --> 00:26:14,819 is one, there's the weak force and 727 00:26:14,820 --> 00:26:16,709 there's the strong force. 728 00:26:16,710 --> 00:26:19,649 And we measured their values 729 00:26:19,650 --> 00:26:21,749 while this the we 730 00:26:21,750 --> 00:26:24,119 measured how strong actually 731 00:26:24,120 --> 00:26:25,769 what we measure is the electric charge, 732 00:26:25,770 --> 00:26:27,089 and that's a measure of how strong the 733 00:26:27,090 --> 00:26:28,829 electromagnetic field is. 734 00:26:28,830 --> 00:26:30,899 And so so this is 735 00:26:30,900 --> 00:26:32,999 actually a measure of the distance 736 00:26:33,000 --> 00:26:35,279 here. So we are here at 737 00:26:35,280 --> 00:26:36,869 long distances away. 738 00:26:36,870 --> 00:26:39,329 We measured the values of the three 739 00:26:41,850 --> 00:26:43,230 of the three charges 740 00:26:44,580 --> 00:26:47,159 here, here and here, and 741 00:26:47,160 --> 00:26:49,829 I told you we can compute the coefficient 742 00:26:49,830 --> 00:26:52,199 of this logarithmic running this beta. 743 00:26:52,200 --> 00:26:54,389 And so we can extrapolate from our 744 00:26:54,390 --> 00:26:57,149 distance scale to other distance scales 745 00:26:57,150 --> 00:26:59,369 are here. So I told you this log 746 00:26:59,370 --> 00:27:01,469 of Q, well, this is 747 00:27:01,470 --> 00:27:03,119 effectively a measure of the distance. 748 00:27:03,120 --> 00:27:04,539 Get a logarithm of the distance. 749 00:27:04,540 --> 00:27:06,659 So this gives you a straight 750 00:27:06,660 --> 00:27:08,819 line and you see that they're almost 751 00:27:08,820 --> 00:27:11,999 meet in the point. Well, not quite 752 00:27:12,000 --> 00:27:13,229 right. 753 00:27:13,230 --> 00:27:15,479 The intersection of the three lines is 754 00:27:15,480 --> 00:27:17,549 pretty close, but it's not in one point. 755 00:27:17,550 --> 00:27:19,109 So pretty close already. 756 00:27:19,110 --> 00:27:21,029 Quite surprising if you have three 757 00:27:21,030 --> 00:27:23,159 generals, straight lines, they 758 00:27:23,160 --> 00:27:24,659 their interactions are all over the 759 00:27:24,660 --> 00:27:26,429 place. But here they almost meet at the 760 00:27:26,430 --> 00:27:29,369 same point. But with supersymmetry, 761 00:27:31,050 --> 00:27:33,149 the coefficient is a little bit different 762 00:27:33,150 --> 00:27:34,739 because the supersymmetric partners 763 00:27:34,740 --> 00:27:36,690 contribute with supersymmetry. 764 00:27:38,340 --> 00:27:40,499 These lines happen to meet all the same 765 00:27:40,500 --> 00:27:42,689 points at some distance scale or 766 00:27:42,690 --> 00:27:44,969 some energy scale 60 767 00:27:44,970 --> 00:27:46,559 10 to the 16. 768 00:27:46,560 --> 00:27:48,959 In this graph, all 769 00:27:48,960 --> 00:27:51,569 the charges happen to be the same, 770 00:27:51,570 --> 00:27:53,549 although at our distance 'cause they're 771 00:27:53,550 --> 00:27:54,550 very different. 772 00:27:57,910 --> 00:28:00,069 So how can this be? So the idea is 773 00:28:00,070 --> 00:28:01,569 that actually these are not three 774 00:28:01,570 --> 00:28:04,449 different forces, but 775 00:28:04,450 --> 00:28:06,789 that this is a single force 776 00:28:06,790 --> 00:28:09,219 that comes about from a rotation 777 00:28:09,220 --> 00:28:11,259 and an even higher dimensional space than 778 00:28:11,260 --> 00:28:13,629 the hyperspace I was showing with Han 779 00:28:13,630 --> 00:28:14,630 and Chewbacca. 780 00:28:16,360 --> 00:28:18,399 Because this braking mechanism, so now I 781 00:28:18,400 --> 00:28:20,979 have tried to draw 782 00:28:20,980 --> 00:28:22,539 the brake and say, here is the blue ball, 783 00:28:22,540 --> 00:28:24,099 but now in the sphere. 784 00:28:24,100 --> 00:28:26,079 And if the blue, if the blue ball sits 785 00:28:26,080 --> 00:28:28,209 here, then a rotation of the 786 00:28:28,210 --> 00:28:30,369 ball around the axis 787 00:28:30,370 --> 00:28:32,529 that goes through this point is still 788 00:28:32,530 --> 00:28:34,869 a symmetry of this configuration. 789 00:28:34,870 --> 00:28:37,479 So the original ball had rotations 790 00:28:37,480 --> 00:28:40,629 about three axes as a symmetry. 791 00:28:40,630 --> 00:28:42,729 But after I placed the 792 00:28:42,730 --> 00:28:44,859 ball here, there's still one 793 00:28:44,860 --> 00:28:47,349 axis where the symmetry 794 00:28:47,350 --> 00:28:49,689 remains and 795 00:28:49,690 --> 00:28:52,209 the rotation about the two other axes 796 00:28:52,210 --> 00:28:53,499 are broken. 797 00:28:53,500 --> 00:28:55,599 So by placing the ball here, 798 00:28:55,600 --> 00:28:58,119 I do not completely remove the symmetry, 799 00:28:58,120 --> 00:28:59,889 but I make it smaller. 800 00:28:59,890 --> 00:29:01,959 Symmetry only rotation about one axis 801 00:29:01,960 --> 00:29:04,239 rather than three axis is the rotation 802 00:29:04,240 --> 00:29:06,639 of this. So the idea is 803 00:29:06,640 --> 00:29:07,640 if I go back. 804 00:29:09,310 --> 00:29:10,959 So also here is the Higgs effect. 805 00:29:10,960 --> 00:29:12,759 So this is the mass of this additional 806 00:29:12,760 --> 00:29:13,959 Higgs particle. 807 00:29:13,960 --> 00:29:17,169 And then there are three independent 808 00:29:17,170 --> 00:29:18,669 remaining symmetries that 809 00:29:19,960 --> 00:29:22,179 after this point, become 810 00:29:22,180 --> 00:29:24,369 one big rotation group while this 811 00:29:24,370 --> 00:29:26,109 rotation group is actually rotation in a 812 00:29:26,110 --> 00:29:27,250 10 dimensional space. 813 00:29:28,390 --> 00:29:29,559 Again, I cannot draw this, 814 00:29:32,620 --> 00:29:33,529 but that is the idea. 815 00:29:33,530 --> 00:29:35,469 So, so this is how this comes about that. 816 00:29:35,470 --> 00:29:37,059 The three lines meet in one point. 817 00:29:37,060 --> 00:29:39,039 They all come from the same symmetry, 818 00:29:39,040 --> 00:29:40,509 highest symmetry. 819 00:29:40,510 --> 00:29:43,179 But this is not the only indication 820 00:29:43,180 --> 00:29:44,949 of this higher symmetry. 821 00:29:44,950 --> 00:29:46,839 Actually, there are more. So this diagram 822 00:29:46,840 --> 00:29:48,039 is called a weight diagram. 823 00:29:48,040 --> 00:29:50,049 I'm going to explain this says all the 824 00:29:50,050 --> 00:29:51,880 particles that we know fit nicely 825 00:29:53,020 --> 00:29:55,149 into groups of particles that transform, 826 00:29:55,150 --> 00:29:57,279 according to this being our symmetry. 827 00:29:57,280 --> 00:29:59,349 So many people believe that 828 00:29:59,350 --> 00:30:01,389 this symmetry is actually a symmetry of 829 00:30:01,390 --> 00:30:02,709 nature. 830 00:30:02,710 --> 00:30:05,469 I mean, at high energies where 831 00:30:05,470 --> 00:30:07,779 the breaking of the symmetry 832 00:30:07,780 --> 00:30:09,819 is undone. And there are also the fact 833 00:30:09,820 --> 00:30:11,709 that the neutrinos have masses and that 834 00:30:11,710 --> 00:30:13,299 there are masses are roughly in the right 835 00:30:13,300 --> 00:30:15,399 range is also an indication that 836 00:30:15,400 --> 00:30:17,139 this thing is going on. 837 00:30:17,140 --> 00:30:19,749 And I showed you this unification. 838 00:30:19,750 --> 00:30:21,219 The meeting of the three lines and one 839 00:30:21,220 --> 00:30:22,899 point happens only with the supersymmetry 840 00:30:22,900 --> 00:30:25,059 without supersymmetry does not happen. 841 00:30:25,060 --> 00:30:27,789 It's ruled out by a current observation. 842 00:30:27,790 --> 00:30:29,859 So if you if you want this, 843 00:30:29,860 --> 00:30:30,969 you need supersymmetry. 844 00:30:33,750 --> 00:30:36,089 The next open 845 00:30:36,090 --> 00:30:37,739 problem that is solved by Susie comes 846 00:30:37,740 --> 00:30:39,449 from a completely different angle of 847 00:30:39,450 --> 00:30:40,709 physics so far, I've talked about 848 00:30:40,710 --> 00:30:41,879 particle physics. 849 00:30:41,880 --> 00:30:44,219 Now let's talk about astrophysics. 850 00:30:44,220 --> 00:30:45,269 This is a galaxy 851 00:30:46,890 --> 00:30:48,749 and we've I mean this picture from Hubble 852 00:30:48,750 --> 00:30:49,750 Space Telescope. 853 00:30:51,300 --> 00:30:53,429 And so as you know, the galaxy is 854 00:30:53,430 --> 00:30:55,559 actually a disk, and we're viewing this 855 00:30:55,560 --> 00:30:58,559 disk from almost from the sign here. 856 00:30:58,560 --> 00:31:00,869 This this one. So the this and this 857 00:31:00,870 --> 00:31:02,969 disk is rotating around an axis that 858 00:31:02,970 --> 00:31:05,039 is almost vertically in this 859 00:31:05,040 --> 00:31:06,040 picture. 860 00:31:06,660 --> 00:31:08,669 And now what you can do by using the 861 00:31:08,670 --> 00:31:10,859 Doppler effect, you can 862 00:31:10,860 --> 00:31:13,499 measure the rotation 863 00:31:13,500 --> 00:31:15,989 velocity of this disk because you know, 864 00:31:15,990 --> 00:31:18,089 when you when the ambulance 865 00:31:18,090 --> 00:31:20,489 comes towards you, the sound 866 00:31:20,490 --> 00:31:22,409 is higher in pitch than when it goes away 867 00:31:22,410 --> 00:31:23,969 from you. Everybody knows the fact called 868 00:31:23,970 --> 00:31:25,349 Doppler effect that also happens for 869 00:31:25,350 --> 00:31:27,689 light and from 870 00:31:27,690 --> 00:31:29,369 observing the frequency. 871 00:31:29,370 --> 00:31:30,959 Or if you like the color of the light of 872 00:31:30,960 --> 00:31:33,689 the stars here, you can determine 873 00:31:33,690 --> 00:31:35,939 the velocity at which 874 00:31:35,940 --> 00:31:37,859 these stars are coming towards us or 875 00:31:37,860 --> 00:31:41,219 moving away. So if this galaxy rotates, 876 00:31:41,220 --> 00:31:43,109 say this way, then the stars here are 877 00:31:43,110 --> 00:31:45,269 coming towards us and the stars here are 878 00:31:45,270 --> 00:31:46,889 moving away from us and this can be 879 00:31:46,890 --> 00:31:47,890 measured. 880 00:31:49,610 --> 00:31:51,919 Right. So are 881 00:31:51,920 --> 00:31:53,509 people observe this for many, many 882 00:31:53,510 --> 00:31:54,889 galaxies. 883 00:31:54,890 --> 00:31:56,149 And the other thing you can do is you can 884 00:31:56,150 --> 00:31:58,009 just look at the picture and kind of 885 00:31:58,010 --> 00:32:01,099 count how many stars are in this galaxy? 886 00:32:01,100 --> 00:32:03,349 Well, not you, but people can. 887 00:32:06,400 --> 00:32:08,649 People have no idea how many, 888 00:32:08,650 --> 00:32:10,239 how many stars in this galaxy, and they 889 00:32:10,240 --> 00:32:11,979 also have no idea how big the stars are 890 00:32:11,980 --> 00:32:14,529 because astronomers again from the 891 00:32:14,530 --> 00:32:17,259 color of the star can determine 892 00:32:17,260 --> 00:32:18,400 the mass of the star. 893 00:32:19,960 --> 00:32:21,130 So you can 894 00:32:22,750 --> 00:32:24,789 see you can actually determine the mass 895 00:32:24,790 --> 00:32:26,589 distribution in this galaxy from looking 896 00:32:26,590 --> 00:32:27,489 at how bright it is. 897 00:32:27,490 --> 00:32:29,199 And so astronomy, that's something that 898 00:32:29,200 --> 00:32:30,999 astronomers can do. 899 00:32:31,000 --> 00:32:33,099 And since the rotation 900 00:32:33,100 --> 00:32:35,469 is balanced so that the centrifugal force 901 00:32:35,470 --> 00:32:37,569 from the rotation is balancing 902 00:32:37,570 --> 00:32:38,979 the gravitational pull 903 00:32:40,060 --> 00:32:41,949 of all the other stars towards the center 904 00:32:41,950 --> 00:32:44,079 of the galaxy by 905 00:32:44,080 --> 00:32:45,879 computing how much mass there is, you 906 00:32:45,880 --> 00:32:47,979 know how strong the gravitational pull 907 00:32:47,980 --> 00:32:50,139 on, say, this star here, 908 00:32:50,140 --> 00:32:52,269 and that determines how fast it has to 909 00:32:52,270 --> 00:32:54,649 go around the center of the galaxy. 910 00:32:54,650 --> 00:32:55,650 So. 911 00:32:55,990 --> 00:32:57,909 So when I say that this disk is rotating, 912 00:32:57,910 --> 00:32:59,619 it doesn't mean that it's uniformly 913 00:32:59,620 --> 00:33:02,019 rotating so that the speed of rotation 914 00:33:02,020 --> 00:33:03,579 can depend on the radius. 915 00:33:03,580 --> 00:33:05,529 Like in the in the Solar System, the 916 00:33:05,530 --> 00:33:07,689 speed at which the planets 917 00:33:07,690 --> 00:33:09,039 fly around the Sun depends on the 918 00:33:09,040 --> 00:33:11,349 distance of the planets from 919 00:33:11,350 --> 00:33:12,939 from the star. 920 00:33:12,940 --> 00:33:15,279 So, uh, so stars 921 00:33:15,280 --> 00:33:17,099 orbit the center of the galaxy, and let's 922 00:33:17,100 --> 00:33:18,459 let's draw a diagram. 923 00:33:18,460 --> 00:33:21,069 I draw this rotation velocity v 924 00:33:21,070 --> 00:33:23,529 against the radius, the distance 925 00:33:23,530 --> 00:33:25,599 from the center of the galaxy. 926 00:33:25,600 --> 00:33:27,849 And I told you from 927 00:33:27,850 --> 00:33:30,249 estimating the mass in the galaxy, 928 00:33:30,250 --> 00:33:32,469 you can predict the velocity 929 00:33:32,470 --> 00:33:35,139 of the star, the velocity of the stars 930 00:33:35,140 --> 00:33:36,529 as a function of the radius. 931 00:33:36,530 --> 00:33:38,259 So that gives you a curve that roughly 932 00:33:38,260 --> 00:33:39,260 looks like this. 933 00:33:40,120 --> 00:33:41,739 And you can measure it using the Doppler 934 00:33:41,740 --> 00:33:43,969 effect and what you measure. 935 00:33:43,970 --> 00:33:44,970 Looks like this. 936 00:33:46,540 --> 00:33:48,279 So obviously, there's something wrong 937 00:33:48,280 --> 00:33:49,280 with your prediction. 938 00:33:52,390 --> 00:33:54,009 So it turns out, I mean, this is the true 939 00:33:54,010 --> 00:33:56,289 thing, and this was predicted on the mass 940 00:33:56,290 --> 00:33:58,359 that you see. So how can this be wrong? 941 00:33:58,360 --> 00:33:59,439 How can you be so wrong? 942 00:33:59,440 --> 00:34:01,509 Well, the only solution is 943 00:34:01,510 --> 00:34:03,879 that you're not seeing all the mass. 944 00:34:03,880 --> 00:34:06,249 Actually, you need more than five times 945 00:34:06,250 --> 00:34:08,799 of the mass of the stars that you see 946 00:34:08,800 --> 00:34:11,529 in the galaxy to get this 947 00:34:11,530 --> 00:34:12,530 rotation curve. 948 00:34:13,960 --> 00:34:16,089 So this curve of velocities that 949 00:34:16,090 --> 00:34:18,189 is almost flat rather than 950 00:34:18,190 --> 00:34:19,928 decaying like this. 951 00:34:19,929 --> 00:34:21,999 So the conclusion is there must be more 952 00:34:22,000 --> 00:34:24,099 mass in this galaxy than 953 00:34:24,100 --> 00:34:26,198 the mass of the of the 954 00:34:26,199 --> 00:34:27,428 atoms in the stars. 955 00:34:28,600 --> 00:34:30,759 And further, from looking 956 00:34:30,760 --> 00:34:33,069 at the details of this curve, 957 00:34:33,070 --> 00:34:34,070 you can determine 958 00:34:35,650 --> 00:34:37,839 what this mass properties of 959 00:34:37,840 --> 00:34:39,069 where the smallest comes about. 960 00:34:39,070 --> 00:34:40,509 So you have to 961 00:34:43,239 --> 00:34:45,369 people conclude that this mass has to 962 00:34:45,370 --> 00:34:48,849 be in the form of heavy, stable particles 963 00:34:48,850 --> 00:34:51,009 so that are only subject 964 00:34:51,010 --> 00:34:53,138 to gravity and the weak force, but not 965 00:34:53,139 --> 00:34:55,119 electrically charged, all strongly 966 00:34:55,120 --> 00:34:57,429 interacting because so high, 967 00:34:57,430 --> 00:34:59,350 so heavy. It means that 968 00:35:00,910 --> 00:35:01,989 they are moving slowly. 969 00:35:01,990 --> 00:35:03,729 They are moving at relativistic speeds 970 00:35:03,730 --> 00:35:05,439 that move much slower than the speed of 971 00:35:05,440 --> 00:35:06,489 light in this galaxy. 972 00:35:06,490 --> 00:35:07,490 Furthermore, 973 00:35:08,680 --> 00:35:10,509 they must go through the stars and 974 00:35:10,510 --> 00:35:11,919 everything that happens in the galaxy 975 00:35:11,920 --> 00:35:12,920 without 976 00:35:14,830 --> 00:35:16,210 interacting with them without 977 00:35:17,530 --> 00:35:19,179 scattering with them, because otherwise 978 00:35:19,180 --> 00:35:21,369 they would also be kind of aligned 979 00:35:21,370 --> 00:35:23,229 with the stars and they are not aligned 980 00:35:23,230 --> 00:35:24,309 with the stars. 981 00:35:24,310 --> 00:35:26,319 And so that determines these the 982 00:35:26,320 --> 00:35:27,249 properties of this particle. 983 00:35:27,250 --> 00:35:28,569 So there has to be there has to be. 984 00:35:28,570 --> 00:35:30,339 And of course, it has to be stable 985 00:35:30,340 --> 00:35:32,709 because these galaxies have been around 986 00:35:32,710 --> 00:35:35,229 for a long, long time 987 00:35:35,230 --> 00:35:37,299 and they wouldn't be 988 00:35:37,300 --> 00:35:39,099 there anymore if these particles that 989 00:35:39,100 --> 00:35:40,779 make up this additional mass would have 990 00:35:40,780 --> 00:35:42,729 decayed in the meantime. 991 00:35:42,730 --> 00:35:43,959 So. 992 00:35:43,960 --> 00:35:46,359 So there has to be have is a heavy 993 00:35:46,360 --> 00:35:48,969 particle that is stable 994 00:35:48,970 --> 00:35:51,299 and not interacting, 995 00:35:51,300 --> 00:35:52,300 not not 996 00:35:53,890 --> 00:35:55,689 having any significant interaction with 997 00:35:55,690 --> 00:35:57,099 the matter of the stars. 998 00:35:57,100 --> 00:35:59,379 And such are such 999 00:35:59,380 --> 00:36:01,029 particles called the WIMP weakly 1000 00:36:01,030 --> 00:36:02,380 interacting massive particle. 1001 00:36:03,760 --> 00:36:05,949 And I should say no WIMPs are 1002 00:36:05,950 --> 00:36:08,349 among the known species of particles. 1003 00:36:08,350 --> 00:36:09,759 So in the standard model, there is no 1004 00:36:09,760 --> 00:36:11,979 particle that that would work 1005 00:36:11,980 --> 00:36:13,449 as a wimp first. 1006 00:36:13,450 --> 00:36:16,029 Some of them are not heavy enough, 1007 00:36:16,030 --> 00:36:17,799 like the neutrinos would be wonderful 1008 00:36:17,800 --> 00:36:19,599 WIMPs, except that they are much too 1009 00:36:19,600 --> 00:36:21,669 light and the heavier 1010 00:36:21,670 --> 00:36:22,670 particles 1011 00:36:25,090 --> 00:36:27,729 wouldn't be kind of non-interactive 1012 00:36:27,730 --> 00:36:29,379 with the stars. 1013 00:36:29,380 --> 00:36:31,599 So there has to be an additional particle 1014 00:36:31,600 --> 00:36:33,669 that makes up this dark matter 1015 00:36:33,670 --> 00:36:35,349 in the galaxy. And it turns out 1016 00:36:35,350 --> 00:36:37,269 supersymmetry provides exactly such a 1017 00:36:37,270 --> 00:36:38,270 particle 1018 00:36:39,520 --> 00:36:41,979 because of the following reason. 1019 00:36:41,980 --> 00:36:43,239 So far, I haven't told you about this, 1020 00:36:43,240 --> 00:36:45,219 but supersymmetric particles have a 1021 00:36:45,220 --> 00:36:47,859 property called all parity. 1022 00:36:47,860 --> 00:36:50,199 Parity is something that can be either +1 1023 00:36:50,200 --> 00:36:52,539 or minus one, and it's +1 1024 00:36:52,540 --> 00:36:54,609 for all the known particles and 1025 00:36:54,610 --> 00:36:57,039 minus one for all the particle, 1026 00:36:57,040 --> 00:36:58,839 the super partners that would have still 1027 00:36:58,840 --> 00:37:01,239 be to be found and 1028 00:37:01,240 --> 00:37:02,419 and that is conserved. 1029 00:37:02,420 --> 00:37:04,509 So the product of this 1030 00:37:04,510 --> 00:37:05,529 party? 1031 00:37:05,530 --> 00:37:07,209 In a particle interaction has to be 1032 00:37:07,210 --> 00:37:09,250 conserved, and that means 1033 00:37:10,480 --> 00:37:12,489 you can only create new particles in 1034 00:37:12,490 --> 00:37:14,199 pairs because the square. 1035 00:37:14,200 --> 00:37:15,789 So each one would contribute a factor of 1036 00:37:15,790 --> 00:37:17,979 minus one. So that's plus 1037 00:37:17,980 --> 00:37:18,909 one. 1038 00:37:18,910 --> 00:37:19,959 So here. 1039 00:37:19,960 --> 00:37:21,489 So this is a process that you have to 1040 00:37:21,490 --> 00:37:22,509 read from left to right, there are two 1041 00:37:22,510 --> 00:37:24,579 quarks interacting giving a W 1042 00:37:24,580 --> 00:37:26,919 boson and that decays now into 1043 00:37:26,920 --> 00:37:29,079 these guys a supersymmetric partners and 1044 00:37:29,080 --> 00:37:30,759 decays into two each. 1045 00:37:30,760 --> 00:37:33,219 One having minus one is our party. 1046 00:37:33,220 --> 00:37:35,409 And then these decay further. 1047 00:37:35,410 --> 00:37:37,599 So this one decays by emitting a new 1048 00:37:37,600 --> 00:37:39,879 neutrino. That's an ordinary particle. 1049 00:37:39,880 --> 00:37:41,739 So and decay, 1050 00:37:43,870 --> 00:37:45,999 there has to be an odd number of new 1051 00:37:46,000 --> 00:37:48,339 particles in the product so that 1052 00:37:48,340 --> 00:37:49,269 here there's one. 1053 00:37:49,270 --> 00:37:51,279 There's a slept on and that again sends 1054 00:37:51,280 --> 00:37:53,829 out an electron and there's 1055 00:37:53,830 --> 00:37:54,969 also a remaining 1056 00:37:56,560 --> 00:37:58,329 supersymmetric partner particle. 1057 00:37:58,330 --> 00:38:00,519 So, so when they're created that 1058 00:38:00,520 --> 00:38:02,589 created in pairs and when they 1059 00:38:02,590 --> 00:38:03,699 decay. 1060 00:38:03,700 --> 00:38:05,439 If there is a supersymmetric partner 1061 00:38:05,440 --> 00:38:07,569 particle in a decade before the 1062 00:38:07,570 --> 00:38:09,069 decay, that has to be one after the 1063 00:38:09,070 --> 00:38:11,439 decay. So the total number of super 1064 00:38:11,440 --> 00:38:13,089 partners in the process always has to be 1065 00:38:13,090 --> 00:38:14,090 an even number. 1066 00:38:15,880 --> 00:38:18,999 And that means if I have a super partner 1067 00:38:19,000 --> 00:38:21,519 and it decays it all the products, 1068 00:38:21,520 --> 00:38:24,849 there's always another super partner. 1069 00:38:24,850 --> 00:38:27,069 And if I have the lightest super partner 1070 00:38:27,070 --> 00:38:28,749 called the LSP the lightest 1071 00:38:28,750 --> 00:38:30,729 supersymmetric particle, it cannot decay 1072 00:38:30,730 --> 00:38:32,709 any further because there is no mass, no 1073 00:38:32,710 --> 00:38:35,139 energy it can decay into, 1074 00:38:35,140 --> 00:38:37,529 and it cannot decay into only stanozolol 1075 00:38:37,530 --> 00:38:38,829 modeling particles because that would 1076 00:38:38,830 --> 00:38:40,839 violate this parity. 1077 00:38:40,840 --> 00:38:43,119 So that makes the light super partner 1078 00:38:43,120 --> 00:38:45,339 stable and therefore 1079 00:38:45,340 --> 00:38:47,529 such a LSP lightest supersymmetric 1080 00:38:47,530 --> 00:38:49,869 particle has accepted the properties 1081 00:38:49,870 --> 00:38:52,059 that we need to explain the dark 1082 00:38:52,060 --> 00:38:53,739 matter and the rotation of galaxies. 1083 00:38:54,880 --> 00:38:56,679 So that's another probe of supersymmetry. 1084 00:38:57,730 --> 00:38:59,769 And finally, again, something close to my 1085 00:38:59,770 --> 00:39:00,939 heart. I'm not going to say anything 1086 00:39:00,940 --> 00:39:03,189 about this. That's we are not stuck 1087 00:39:03,190 --> 00:39:04,749 with particles. There's also super 1088 00:39:04,750 --> 00:39:07,179 strings. And if you ever want to make a 1089 00:39:07,180 --> 00:39:08,919 realistic model out of super strings, 1090 00:39:08,920 --> 00:39:10,569 that gives you a standard model particles 1091 00:39:10,570 --> 00:39:11,859 their own. 1092 00:39:11,860 --> 00:39:14,199 The only way we know to do this is 1093 00:39:14,200 --> 00:39:16,329 also to actually create the super 1094 00:39:16,330 --> 00:39:17,769 symmetric version of the standard model, 1095 00:39:17,770 --> 00:39:19,269 but I'm not going to say anything more 1096 00:39:19,270 --> 00:39:21,009 about this. So super strings also want 1097 00:39:21,010 --> 00:39:22,010 supersymmetry. 1098 00:39:24,230 --> 00:39:26,719 OK, so these five problems 1099 00:39:26,720 --> 00:39:29,509 out of which I try to explain, three 1100 00:39:29,510 --> 00:39:31,669 are all reason 1101 00:39:31,670 --> 00:39:34,099 to believe that supersymmetry is actually 1102 00:39:34,100 --> 00:39:35,179 a good idea to have. 1103 00:39:36,260 --> 00:39:37,790 So let's look for it. 1104 00:39:40,450 --> 00:39:42,039 And then what we look for. 1105 00:39:43,300 --> 00:39:45,219 So that is and there's unfortunately a 1106 00:39:45,220 --> 00:39:46,220 problem 1107 00:39:48,400 --> 00:39:49,689 and particularly the breaking of the 1108 00:39:49,690 --> 00:39:51,129 super symmetry. Remember, we needed to 1109 00:39:51,130 --> 00:39:53,259 break it because we need the 1110 00:39:53,260 --> 00:39:54,670 super partners to be heavy. 1111 00:39:56,080 --> 00:39:58,389 It comes that's not in 1112 00:39:58,390 --> 00:40:01,419 the 120 parameters 1113 00:40:01,420 --> 00:40:03,039 to 120 numeric parameters. 1114 00:40:03,040 --> 00:40:04,479 You should compare this to the 19 1115 00:40:04,480 --> 00:40:05,919 parameters that we have in the standard. 1116 00:40:05,920 --> 00:40:08,169 So again, there's not the standard model, 1117 00:40:08,170 --> 00:40:10,419 but there is a 19 dimensional space 1118 00:40:10,420 --> 00:40:11,859 of standard models. You can you have to 1119 00:40:11,860 --> 00:40:13,929 to choose 90 numbers. 1120 00:40:13,930 --> 00:40:15,429 Here I've listed the ones of the standard 1121 00:40:15,430 --> 00:40:17,679 model, so you have to choose the mass 1122 00:40:17,680 --> 00:40:19,359 of the electron, the mass of the other 1123 00:40:19,360 --> 00:40:21,549 particles you have to. 1124 00:40:21,550 --> 00:40:23,829 There are some mixing angles, blah 1125 00:40:23,830 --> 00:40:25,599 blah. In total, there are 19 numbers that 1126 00:40:25,600 --> 00:40:26,859 you have to measure. 1127 00:40:26,860 --> 00:40:28,809 These 90 numbers determine the standard 1128 00:40:28,810 --> 00:40:31,029 model. Unfortunately for 1129 00:40:31,030 --> 00:40:32,679 supersymmetry, you need to measure how 1130 00:40:32,680 --> 00:40:34,779 many parameters to determine exactly 1131 00:40:34,780 --> 00:40:37,059 which incarnation 1132 00:40:37,060 --> 00:40:39,279 of the super symmetric of 1133 00:40:39,280 --> 00:40:40,699 the minimum supersymmetric started when 1134 00:40:40,700 --> 00:40:41,829 you have. 1135 00:40:41,830 --> 00:40:43,989 So if you measure something, 1136 00:40:43,990 --> 00:40:46,449 for example, of LHC after his 1137 00:40:46,450 --> 00:40:48,459 speed spits it, well, first you would 1138 00:40:48,460 --> 00:40:50,139 have to measure these how many parameters 1139 00:40:50,140 --> 00:40:52,609 or you make an assumption about the 1140 00:40:52,610 --> 00:40:54,489 the values of these parameters, and then 1141 00:40:54,490 --> 00:40:57,249 you check whether that's realized or not. 1142 00:40:57,250 --> 00:40:59,439 So you can turn 1143 00:40:59,440 --> 00:41:00,999 this argument around and say that is with 1144 00:41:01,000 --> 00:41:02,919 how many parameters there's plenty of 1145 00:41:02,920 --> 00:41:04,749 room to avoid detection. 1146 00:41:04,750 --> 00:41:06,369 So if you don't see anything, you say, 1147 00:41:06,370 --> 00:41:08,289 Oh, maybe the pyramids have different 1148 00:41:08,290 --> 00:41:10,510 values and you can go on, 1149 00:41:11,530 --> 00:41:13,659 and every measurement that you make 1150 00:41:13,660 --> 00:41:15,909 is relative to some choices for some 1151 00:41:15,910 --> 00:41:17,499 or at least some of these parameters. 1152 00:41:18,610 --> 00:41:20,439 So, so looking for supersymmetry is 1153 00:41:20,440 --> 00:41:21,969 actually a hard thing because 1154 00:41:23,050 --> 00:41:25,479 you have to determine a lot of numbers. 1155 00:41:25,480 --> 00:41:27,609 And our best way to look for it for 1156 00:41:27,610 --> 00:41:29,769 supersymmetry is at the Large 1157 00:41:29,770 --> 00:41:32,289 Hadron Collider at CERN in Geneva. 1158 00:41:32,290 --> 00:41:34,179 So, yeah, I gave you the picture that I 1159 00:41:34,180 --> 00:41:35,799 hope you've seen many times before in the 1160 00:41:35,800 --> 00:41:37,929 popular press. This is the collider 1161 00:41:37,930 --> 00:41:40,389 ring somewhere here. 1162 00:41:40,390 --> 00:41:42,039 This is the computing center or the 1163 00:41:42,040 --> 00:41:44,259 control center on on the CERN ground, 1164 00:41:44,260 --> 00:41:46,569 but they're at several points 1165 00:41:46,570 --> 00:41:47,570 in the ring there. 1166 00:41:48,880 --> 00:41:50,709 Detectors were actually experiments of 1167 00:41:50,710 --> 00:41:52,659 and in particular, there are two of them 1168 00:41:52,660 --> 00:41:54,789 here CMS and here Atlas are big 1169 00:41:54,790 --> 00:41:57,189 detectors where the 1170 00:41:57,190 --> 00:41:58,929 two beams that are running that are 1171 00:41:58,930 --> 00:42:01,149 running around in the pipe here 1172 00:42:01,150 --> 00:42:02,439 are we're colliding. 1173 00:42:02,440 --> 00:42:05,379 So yesterday there was a talk about LHC 1174 00:42:05,380 --> 00:42:07,269 that I hope explained this in much more 1175 00:42:07,270 --> 00:42:09,099 detail than I can. 1176 00:42:09,100 --> 00:42:11,229 So this for the for today, this all 1177 00:42:11,230 --> 00:42:13,479 you have to know two detectors called 1178 00:42:13,480 --> 00:42:15,699 Atlas and CMS that are different, 1179 00:42:15,700 --> 00:42:17,439 but in principle, measuring the same 1180 00:42:17,440 --> 00:42:18,440 thing. 1181 00:42:19,900 --> 00:42:21,069 And there's another problem with the 1182 00:42:21,070 --> 00:42:22,909 Large Hadron Collider, and that's harder 1183 00:42:22,910 --> 00:42:24,279 on hydrogen. 1184 00:42:24,280 --> 00:42:26,679 This is a type of particle and 1185 00:42:26,680 --> 00:42:29,079 protons are 1186 00:42:29,080 --> 00:42:31,209 examples of hadrons and protons, 1187 00:42:31,210 --> 00:42:32,949 but none of these other things in the 1188 00:42:32,950 --> 00:42:34,029 nucleus of an atom. 1189 00:42:34,030 --> 00:42:37,029 These are the things that are accelerated 1190 00:42:37,030 --> 00:42:39,159 at LHC because 1191 00:42:39,160 --> 00:42:41,079 they're easy to accelerate to say it, in 1192 00:42:41,080 --> 00:42:42,009 short. 1193 00:42:42,010 --> 00:42:44,169 The problem is, remember, in 1194 00:42:44,170 --> 00:42:45,669 my list of particles, there were no 1195 00:42:45,670 --> 00:42:47,889 protons because they are not 1196 00:42:47,890 --> 00:42:49,839 elementary. They consist of quarks, they 1197 00:42:49,840 --> 00:42:51,009 consist of three quarks. 1198 00:42:51,010 --> 00:42:52,359 And actually because of this ring 1199 00:42:52,360 --> 00:42:54,009 normalization effect and particles 1200 00:42:54,010 --> 00:42:55,779 popping out of the vacuum. 1201 00:42:55,780 --> 00:42:57,189 And these energies that we're looking at, 1202 00:42:57,190 --> 00:42:59,349 they're actually of 1203 00:42:59,350 --> 00:43:01,449 more or less 2000 particles. 1204 00:43:01,450 --> 00:43:03,279 So a proton is a cloud of two thousand 1205 00:43:03,280 --> 00:43:05,589 particles, including 1206 00:43:05,590 --> 00:43:06,729 the ones that are popping out from the 1207 00:43:06,730 --> 00:43:08,589 vacuum that you are accelerating and then 1208 00:43:08,590 --> 00:43:10,089 you collide them. 1209 00:43:10,090 --> 00:43:12,589 And when you collide two protons at LHC, 1210 00:43:12,590 --> 00:43:14,319 you're not colliding to protons, but 1211 00:43:14,320 --> 00:43:16,419 actually you pick from 1212 00:43:16,420 --> 00:43:18,399 from the from each proton and pick one of 1213 00:43:18,400 --> 00:43:20,529 these two thousand particles and 1214 00:43:20,530 --> 00:43:23,229 you collide these two, 1215 00:43:23,230 --> 00:43:25,539 these two particles and all 1216 00:43:25,540 --> 00:43:27,759 the twice one thousand 1217 00:43:27,760 --> 00:43:29,439 nine hundred ninety nine roughly 1218 00:43:29,440 --> 00:43:32,619 particles just fly through as bystanders. 1219 00:43:32,620 --> 00:43:33,759 And that makes this process. 1220 00:43:33,760 --> 00:43:35,679 So that's a depiction of such collision. 1221 00:43:35,680 --> 00:43:37,329 Very hard to analyze because there's a 1222 00:43:37,330 --> 00:43:38,829 lot of garbage flying around. 1223 00:43:41,710 --> 00:43:45,189 Also, these collisions happen 1224 00:43:45,190 --> 00:43:47,499 while the the the beams have 1225 00:43:47,500 --> 00:43:49,629 have a collision energy of 8V. 1226 00:43:49,630 --> 00:43:51,759 But the 8V is distributed among 1227 00:43:51,760 --> 00:43:53,859 these twice 20 particles, so the 1228 00:43:53,860 --> 00:43:55,959 collision happens only with a small 1229 00:43:55,960 --> 00:43:57,460 fraction of these 8V. 1230 00:43:58,750 --> 00:44:00,849 And we don't know which fraction 1231 00:44:00,850 --> 00:44:03,009 because we don't know the details of 1232 00:44:03,010 --> 00:44:04,389 the particles. 1233 00:44:04,390 --> 00:44:06,219 So we have to look at lots of these 1234 00:44:06,220 --> 00:44:08,349 processes. Get rid of the 1235 00:44:08,350 --> 00:44:10,419 DBRS and do 1236 00:44:10,420 --> 00:44:12,129 statistical analysis on this, and that's 1237 00:44:12,130 --> 00:44:13,029 actually quite hard. 1238 00:44:13,030 --> 00:44:14,559 So it's not something you turn on. 1239 00:44:14,560 --> 00:44:15,940 You see immediately see something. 1240 00:44:17,350 --> 00:44:19,539 So that's a picture of of this 1241 00:44:19,540 --> 00:44:20,560 atlas detector. 1242 00:44:21,590 --> 00:44:23,739 You see a person that gives 1243 00:44:23,740 --> 00:44:25,989 you an idea how big this thing is. 1244 00:44:25,990 --> 00:44:28,089 This is a well, I mean, 1245 00:44:28,090 --> 00:44:29,949 this is from the construction of of the 1246 00:44:29,950 --> 00:44:32,109 detector. This is the detector with 1247 00:44:32,110 --> 00:44:33,459 the inner part of the detector. 1248 00:44:33,460 --> 00:44:36,159 Remove you. You look along the beam pipe 1249 00:44:36,160 --> 00:44:37,089 here. 1250 00:44:37,090 --> 00:44:39,399 This stuff is actually this empty 1251 00:44:39,400 --> 00:44:41,769 space is actually filled with detector. 1252 00:44:41,770 --> 00:44:43,029 This is only the outer part of the 1253 00:44:43,030 --> 00:44:44,979 detector. And here you see the beam part 1254 00:44:44,980 --> 00:44:46,569 like this, and this is part of the 1255 00:44:46,570 --> 00:44:48,399 detector, the mean detector. 1256 00:44:48,400 --> 00:44:50,289 So to get an idea of how big this is, so 1257 00:44:50,290 --> 00:44:52,449 this is a multi-story building. 1258 00:44:52,450 --> 00:44:55,059 If you be there several 1259 00:44:55,060 --> 00:44:56,260 stories underground 1260 00:44:57,640 --> 00:45:00,099 and this is 1261 00:45:00,100 --> 00:45:01,599 what this detector measures are. 1262 00:45:01,600 --> 00:45:03,339 Actually, this is a simulation. 1263 00:45:03,340 --> 00:45:05,589 What you see here, the beam pipe goes 1264 00:45:05,590 --> 00:45:06,669 here in the middle. 1265 00:45:06,670 --> 00:45:08,979 So some one 1266 00:45:08,980 --> 00:45:10,209 beam of protons comes from here. 1267 00:45:10,210 --> 00:45:11,379 The other beam of product comes from here 1268 00:45:11,380 --> 00:45:13,449 and here they're supposed to collide. 1269 00:45:13,450 --> 00:45:15,579 And when they collide, they go through 1270 00:45:15,580 --> 00:45:17,799 several shells of detectors and 1271 00:45:17,800 --> 00:45:20,019 the innermost shell. 1272 00:45:20,020 --> 00:45:22,119 This consists of of a detector type 1273 00:45:22,120 --> 00:45:24,279 where you can track the particles 1274 00:45:24,280 --> 00:45:26,019 and the next shell. 1275 00:45:26,020 --> 00:45:28,239 There, you can only see the energy 1276 00:45:28,240 --> 00:45:29,979 that is deposited in the detector and 1277 00:45:29,980 --> 00:45:32,169 that's indicated by these yellow 1278 00:45:32,170 --> 00:45:34,209 bars. And then some particles named the 1279 00:45:34,210 --> 00:45:36,309 muons make only those make 1280 00:45:36,310 --> 00:45:38,289 it out of this initial of the detector 1281 00:45:38,290 --> 00:45:39,849 and reach the outer part, and there again 1282 00:45:39,850 --> 00:45:42,159 tracks where it can detect 1283 00:45:42,160 --> 00:45:44,439 them. This is how one such collision 1284 00:45:44,440 --> 00:45:45,909 looks like, and there are millions and 1285 00:45:45,910 --> 00:45:48,219 millions of those every second. 1286 00:45:48,220 --> 00:45:50,289 So this is what you're seeing 1287 00:45:50,290 --> 00:45:52,419 are now. 1288 00:45:52,420 --> 00:45:54,879 What would super symmetry look like? 1289 00:45:54,880 --> 00:45:56,739 And the answer is the smoking gun for 1290 00:45:56,740 --> 00:45:59,289 supersymmetry is that you don't see it 1291 00:45:59,290 --> 00:46:01,509 in which sense, well, I explain to you 1292 00:46:01,510 --> 00:46:03,879 that the LSP, the lightest 1293 00:46:03,880 --> 00:46:05,589 supersymmetric particle, doesn't interact 1294 00:46:05,590 --> 00:46:07,979 with matter, so it's invisible 1295 00:46:07,980 --> 00:46:09,549 to the detector. It just flies out of the 1296 00:46:09,550 --> 00:46:10,749 detector and you don't see it. 1297 00:46:12,370 --> 00:46:14,170 You only see the rest of the particles, 1298 00:46:15,550 --> 00:46:17,769 but you see that the remaining particles 1299 00:46:17,770 --> 00:46:20,139 seem to violate momentum 1300 00:46:20,140 --> 00:46:22,269 conservation and 1301 00:46:22,270 --> 00:46:24,429 momentum conservation. This view 1302 00:46:24,430 --> 00:46:26,289 is hard to determine because see, there 1303 00:46:26,290 --> 00:46:27,819 is no detector along the beam pipes, so 1304 00:46:27,820 --> 00:46:30,039 most of the stuff just flies 1305 00:46:30,040 --> 00:46:31,659 in. Still, in the compartment is not 1306 00:46:31,660 --> 00:46:33,729 detected, but if you view 1307 00:46:33,730 --> 00:46:35,709 the detector head on, so now this is 1308 00:46:35,710 --> 00:46:37,809 again looking along the 1309 00:46:37,810 --> 00:46:39,909 beam pipe, you see that here is 1310 00:46:39,910 --> 00:46:40,869 stuff going here. 1311 00:46:40,870 --> 00:46:42,519 Is stuff going on here, stuff going. 1312 00:46:42,520 --> 00:46:44,679 But everything is a little bit more to 1313 00:46:44,680 --> 00:46:46,059 the right than to the left. 1314 00:46:46,060 --> 00:46:47,829 There's nothing to the left. 1315 00:46:47,830 --> 00:46:49,239 And both of them are to the right. 1316 00:46:49,240 --> 00:46:51,339 So since the beam has 1317 00:46:51,340 --> 00:46:53,439 no momentum transfers to 1318 00:46:53,440 --> 00:46:55,689 the beam. This means in 1319 00:46:55,690 --> 00:46:57,339 this collision, there must have been 1320 00:46:57,340 --> 00:46:59,409 something that went this way 1321 00:46:59,410 --> 00:47:00,460 with lots of energy 1322 00:47:01,480 --> 00:47:03,609 to balance the 1323 00:47:03,610 --> 00:47:05,409 tendency of all the rats to go to the 1324 00:47:05,410 --> 00:47:07,509 right. So this means here 1325 00:47:07,510 --> 00:47:09,669 some particle has been created that we 1326 00:47:09,670 --> 00:47:11,559 don't see, and this is what supersymmetry 1327 00:47:11,560 --> 00:47:12,879 would look look like. 1328 00:47:12,880 --> 00:47:15,069 You would see an imbalance of energy. 1329 00:47:16,690 --> 00:47:17,919 So this is what this is. 1330 00:47:17,920 --> 00:47:19,999 The. We are looking for 1331 00:47:20,000 --> 00:47:21,409 and there are some other more subtle 1332 00:47:21,410 --> 00:47:24,769 effects that also indicate supersymmetry, 1333 00:47:24,770 --> 00:47:26,779 and our expectation for LHC was I 1334 00:47:26,780 --> 00:47:28,549 remember a couple of years ago before the 1335 00:47:28,550 --> 00:47:30,619 LHC was turned on, I heard talks that 1336 00:47:30,620 --> 00:47:32,899 said all within actually five minutes. 1337 00:47:32,900 --> 00:47:35,029 If not, then in 1338 00:47:35,030 --> 00:47:36,739 a week we discover supersymmetry. 1339 00:47:36,740 --> 00:47:38,839 That was the expectation of particle 1340 00:47:38,840 --> 00:47:40,969 physicist for the LHC. 1341 00:47:40,970 --> 00:47:43,129 But when it was actually turned on and I 1342 00:47:43,130 --> 00:47:45,259 actually was going, even the Fuhrer 1343 00:47:45,260 --> 00:47:46,729 had to land. 1344 00:47:46,730 --> 00:47:48,559 And we have not seen any direct evidence 1345 00:47:48,560 --> 00:47:50,539 for supersymmetry at LHC, although we 1346 00:47:50,540 --> 00:47:51,649 expected to see it there. 1347 00:47:53,270 --> 00:47:54,270 So 1348 00:47:55,930 --> 00:47:58,189 in a more technical way, these 1349 00:47:58,190 --> 00:48:00,439 are this is actually a picture from 1350 00:48:00,440 --> 00:48:02,539 from publication, from this 1351 00:48:02,540 --> 00:48:04,159 one, from the steam detector. 1352 00:48:04,160 --> 00:48:05,719 This is what they publish about 1353 00:48:05,720 --> 00:48:06,829 supersymmetry. 1354 00:48:06,830 --> 00:48:08,959 These are bounds 1355 00:48:08,960 --> 00:48:10,849 that you're supposed to read like this. 1356 00:48:10,850 --> 00:48:12,739 This is an enormous scale and energy 1357 00:48:12,740 --> 00:48:15,019 scale, and these are all types 1358 00:48:15,020 --> 00:48:16,489 of different supersymmetric partner 1359 00:48:16,490 --> 00:48:18,619 particles that and 1360 00:48:18,620 --> 00:48:20,809 also different processes in which they 1361 00:48:20,810 --> 00:48:22,609 would would have been created. 1362 00:48:22,610 --> 00:48:24,679 And you're supposed to read this as if 1363 00:48:24,680 --> 00:48:26,009 super points exist. 1364 00:48:26,010 --> 00:48:29,209 They have to be heavier than bluh 1365 00:48:29,210 --> 00:48:31,039 in order that we wouldn't have seen them 1366 00:48:31,040 --> 00:48:32,479 so far. 1367 00:48:32,480 --> 00:48:34,939 So all these are so-called mass 1368 00:48:34,940 --> 00:48:37,009 bound. So you see that 1369 00:48:37,010 --> 00:48:38,629 the super partners would be have to be 1370 00:48:38,630 --> 00:48:40,609 heavier while depending on the type and 1371 00:48:40,610 --> 00:48:43,039 the process, then these numbers 1372 00:48:43,040 --> 00:48:45,139 and I explain in the beginning that we 1373 00:48:45,140 --> 00:48:47,119 would have expected them at 100 GB, which 1374 00:48:47,120 --> 00:48:48,120 is here. 1375 00:48:50,430 --> 00:48:51,430 So 1376 00:48:53,820 --> 00:48:55,020 there's obviously a problem. 1377 00:48:56,310 --> 00:48:57,509 So now what? 1378 00:48:57,510 --> 00:48:59,579 As you know, there are known unknowns and 1379 00:48:59,580 --> 00:49:01,259 unknown unknowns, as this famous 1380 00:49:01,260 --> 00:49:02,790 philosopher explained. 1381 00:49:05,040 --> 00:49:07,469 So what can we do? So I mean the easy, 1382 00:49:07,470 --> 00:49:09,119 the easy way to wiggle out to say this, 1383 00:49:09,120 --> 00:49:10,499 to say, Oh, there's still room in the 1384 00:49:10,500 --> 00:49:12,119 parameter space. We can tune some of the 1385 00:49:12,120 --> 00:49:14,249 under-20 parameters in such 1386 00:49:14,250 --> 00:49:16,739 a way that 1387 00:49:16,740 --> 00:49:18,539 that are compatible with the bounds that 1388 00:49:18,540 --> 00:49:20,369 we obtained from the experiments. 1389 00:49:21,450 --> 00:49:23,459 The other possibility is to say, Well, 1390 00:49:23,460 --> 00:49:24,959 maybe this was only the simplest version. 1391 00:49:24,960 --> 00:49:26,789 I accept this is the minimal 1392 00:49:26,790 --> 00:49:28,139 supersymmetric version. 1393 00:49:28,140 --> 00:49:30,509 We can also come up with extra 1394 00:49:30,510 --> 00:49:32,719 stuff, even more particles, and 1395 00:49:32,720 --> 00:49:34,859 in these more contrived models, 1396 00:49:34,860 --> 00:49:36,689 again, there's even more wiggle room to 1397 00:49:36,690 --> 00:49:37,690 say, Well, 1398 00:49:39,150 --> 00:49:41,159 this could explain why we haven't seen it 1399 00:49:41,160 --> 00:49:43,140 so far. But of course, these more 1400 00:49:44,160 --> 00:49:46,049 complicated models are more baroque and 1401 00:49:46,050 --> 00:49:48,719 even harder to 1402 00:49:48,720 --> 00:49:50,999 well motivated. 1403 00:49:51,000 --> 00:49:53,339 Or simply 1404 00:49:53,340 --> 00:49:55,679 the high-energy v scale supersymmetry 1405 00:49:55,680 --> 00:49:57,329 that would have explained Naturalis is 1406 00:49:57,330 --> 00:49:59,339 not in its nature, a solution to 1407 00:49:59,340 --> 00:50:00,839 naturalness. 1408 00:50:00,840 --> 00:50:03,119 And but then 1409 00:50:03,120 --> 00:50:04,380 so do we have to forget Suzy? 1410 00:50:05,670 --> 00:50:07,709 Well, maybe not. 1411 00:50:10,200 --> 00:50:12,419 But if Susy is not realized in nature 1412 00:50:12,420 --> 00:50:14,759 and these solutions to look 1413 00:50:14,760 --> 00:50:16,919 for some other regions parameter 1414 00:50:16,920 --> 00:50:18,959 space, this would mean would have to come 1415 00:50:18,960 --> 00:50:21,569 up with new solutions 1416 00:50:21,570 --> 00:50:23,519 to these five problems that Suzy is 1417 00:50:23,520 --> 00:50:25,199 actually solving for us. 1418 00:50:25,200 --> 00:50:27,539 And I have to say not 1419 00:50:27,540 --> 00:50:29,879 any good alternative candidate 1420 00:50:29,880 --> 00:50:30,869 here is known. 1421 00:50:30,870 --> 00:50:32,679 There are some for naturalness, but there 1422 00:50:32,680 --> 00:50:34,799 there are even weaker physiological 1423 00:50:34,800 --> 00:50:36,300 basis than supersymmetry. 1424 00:50:37,410 --> 00:50:39,779 So my take-home message is, 1425 00:50:39,780 --> 00:50:41,909 are I trying to explain 1426 00:50:41,910 --> 00:50:44,009 that supersymmetry offers solutions to 1427 00:50:44,010 --> 00:50:46,379 some of the most pressing open questions 1428 00:50:46,380 --> 00:50:47,699 in particle physics? 1429 00:50:47,700 --> 00:50:48,750 But unfortunately, 1430 00:50:49,770 --> 00:50:51,449 it's not as easy as we had hoped. 1431 00:50:52,860 --> 00:50:56,279 We haven't seen it, although we expected. 1432 00:50:56,280 --> 00:50:57,659 But there's hope for the next round of 1433 00:50:57,660 --> 00:50:59,010 LHC. Currently, LHC 1434 00:51:00,180 --> 00:51:01,139 is not running. 1435 00:51:01,140 --> 00:51:02,140 It's 1436 00:51:03,750 --> 00:51:05,909 while people put in more stuff to 1437 00:51:05,910 --> 00:51:07,529 make it run at even higher energies and 1438 00:51:07,530 --> 00:51:09,359 higher collision rates. 1439 00:51:09,360 --> 00:51:11,039 So we hope that within 1440 00:51:12,150 --> 00:51:14,609 version two of LHC, 1441 00:51:14,610 --> 00:51:16,679 more collisions at higher energy that 1442 00:51:16,680 --> 00:51:18,509 those reveals supersymmetry and if not, 1443 00:51:18,510 --> 00:51:20,669 then we have to come up with other 1444 00:51:20,670 --> 00:51:21,149 ideas. 1445 00:51:21,150 --> 00:51:22,150 So 1446 00:51:23,790 --> 00:51:24,790 thanks for lot. 1447 00:51:31,430 --> 00:51:32,430 So 1448 00:51:33,950 --> 00:51:35,359 we have 1449 00:51:35,360 --> 00:51:37,099 we have about 10, 10 minutes here for 1450 00:51:37,100 --> 00:51:39,559 questions if you have any questions, 1451 00:51:39,560 --> 00:51:41,719 if you can use the two microphones in the 1452 00:51:41,720 --> 00:51:44,029 in the two aisles and 1453 00:51:44,030 --> 00:51:46,369 I'll go form 1454 00:51:46,370 --> 00:51:47,869 two neat, neat lines. 1455 00:51:47,870 --> 00:51:50,509 And we'll start with 1456 00:51:50,510 --> 00:51:52,999 this gentleman here and then work 1457 00:51:53,000 --> 00:51:54,000 one two one two. 1458 00:51:55,370 --> 00:51:57,169 So you said that the WIMP candidates 1459 00:51:57,170 --> 00:51:59,059 would have to interact weekly as well, 1460 00:52:00,170 --> 00:52:02,179 but at most weekly 1461 00:52:02,180 --> 00:52:03,259 at most weekly? 1462 00:52:03,260 --> 00:52:04,579 Yes. 1463 00:52:04,580 --> 00:52:06,979 If oh, so it's possible that they 1464 00:52:06,980 --> 00:52:09,199 would not partake in the week interaction 1465 00:52:09,200 --> 00:52:10,759 because I was thinking that you have some 1466 00:52:10,760 --> 00:52:13,009 events in the universe, which 1467 00:52:13,010 --> 00:52:14,749 are very extreme manifestations of the 1468 00:52:14,750 --> 00:52:17,179 weak interactions like supernovae 1469 00:52:17,180 --> 00:52:19,519 where you get an enormous number of 1470 00:52:19,520 --> 00:52:21,859 neutrinos and enormous densities 1471 00:52:21,860 --> 00:52:23,119 of neutrinos. 1472 00:52:23,120 --> 00:52:25,219 And if if we should not 1473 00:52:25,220 --> 00:52:27,319 expect some sort of effect between 1474 00:52:27,320 --> 00:52:29,419 WIMPs and neutrinos from a 1475 00:52:29,420 --> 00:52:31,429 supernova, which would be observable 1476 00:52:32,450 --> 00:52:34,609 well, whether they 1477 00:52:34,610 --> 00:52:36,079 have to partake in some interaction, 1478 00:52:36,080 --> 00:52:37,249 otherwise we couldn't. 1479 00:52:37,250 --> 00:52:38,719 We could never create those particles. 1480 00:52:38,720 --> 00:52:39,860 So that's the first thing. 1481 00:52:42,320 --> 00:52:43,789 And then you are mixing things up. 1482 00:52:43,790 --> 00:52:46,309 So indeed, a supernova is a very 1483 00:52:46,310 --> 00:52:49,339 big energy concept. 1484 00:52:49,340 --> 00:52:51,559 But the when 1485 00:52:51,560 --> 00:52:53,779 I said these are high energies, even this 1486 00:52:53,780 --> 00:52:56,209 10 to the 19 TV Planck scale 1487 00:52:56,210 --> 00:52:58,369 this as a mass from every 1488 00:52:58,370 --> 00:53:01,219 day scale that's mg 1489 00:53:01,220 --> 00:53:03,439 microgram now. So I mean, 1490 00:53:03,440 --> 00:53:05,629 me doing this is a much 1491 00:53:05,630 --> 00:53:07,879 higher energy process 1492 00:53:07,880 --> 00:53:09,769 than any any plunks go process. 1493 00:53:09,770 --> 00:53:11,929 The problem is when I do this, I'm 1494 00:53:11,930 --> 00:53:13,070 not a single particle, 1495 00:53:14,630 --> 00:53:16,789 but by that consists 1496 00:53:16,790 --> 00:53:18,949 of two 10 to the twenty 1497 00:53:18,950 --> 00:53:21,079 three particles and they share this 1498 00:53:21,080 --> 00:53:22,759 energy and again, a supernova. 1499 00:53:22,760 --> 00:53:24,739 I mean, that's a whole star exploding. 1500 00:53:24,740 --> 00:53:26,869 So yes, it has much, much higher 1501 00:53:26,870 --> 00:53:29,059 energy, but distributed among 1502 00:53:29,060 --> 00:53:30,649 all the particles that make up the star. 1503 00:53:30,650 --> 00:53:32,959 So yes 1504 00:53:32,960 --> 00:53:34,670 and no, thanks. 1505 00:53:36,740 --> 00:53:38,300 Well, it's actually the question. 1506 00:53:41,740 --> 00:53:42,999 This gentleman over here. 1507 00:53:43,000 --> 00:53:43,599 OK. 1508 00:53:43,600 --> 00:53:45,849 And my question is, if there are such 1509 00:53:45,850 --> 00:53:48,819 particles which do not interact 1510 00:53:48,820 --> 00:53:50,859 electromagnetically with other parts but 1511 00:53:50,860 --> 00:53:51,879 have mass? 1512 00:53:51,880 --> 00:53:53,979 Shouldn't they concentrate in the center 1513 00:53:53,980 --> 00:53:55,989 of a galaxy and change again? 1514 00:53:55,990 --> 00:53:56,979 The rotation a little bit. 1515 00:53:56,980 --> 00:54:00,039 No, no. Because of momentum conservation. 1516 00:54:00,040 --> 00:54:01,149 They just fly. 1517 00:54:01,150 --> 00:54:02,739 I mean, they don't. They only feel the 1518 00:54:02,740 --> 00:54:05,469 mass. They just fly around on 1519 00:54:05,470 --> 00:54:07,479 on big orbits. Nothing kind of. 1520 00:54:07,480 --> 00:54:09,549 There's no friction that makes them 1521 00:54:09,550 --> 00:54:11,559 fall into. So let me go back to my 1522 00:54:11,560 --> 00:54:13,029 picture of the galaxy. 1523 00:54:13,030 --> 00:54:13,959 No. 1524 00:54:13,960 --> 00:54:15,149 Back, back, back, back, back, back, back, 1525 00:54:15,150 --> 00:54:17,389 back, back, back, back, back, back, 1526 00:54:17,390 --> 00:54:19,089 back, back, back. 1527 00:54:19,090 --> 00:54:21,279 Here's my picture of a galaxy. 1528 00:54:21,280 --> 00:54:23,469 The the fact that the galaxy 1529 00:54:23,470 --> 00:54:25,659 is a disk comes actually from 1530 00:54:25,660 --> 00:54:26,679 the friction. 1531 00:54:26,680 --> 00:54:27,759 So it starts out. 1532 00:54:27,760 --> 00:54:29,889 I mean, early in cosmic evolution, there 1533 00:54:29,890 --> 00:54:31,539 was just stuff flying around. 1534 00:54:31,540 --> 00:54:32,830 So it was more or less 1535 00:54:34,210 --> 00:54:36,369 about three dimensional 1536 00:54:36,370 --> 00:54:37,509 thing. 1537 00:54:37,510 --> 00:54:39,100 But then it has rotation, 1538 00:54:40,510 --> 00:54:41,859 so it has angular momentum. 1539 00:54:41,860 --> 00:54:44,439 And because the stars, 1540 00:54:44,440 --> 00:54:45,669 they actually feel each other. 1541 00:54:45,670 --> 00:54:47,499 I mean, the stars, I mean, they interact 1542 00:54:47,500 --> 00:54:49,479 gravitationally and they're heavy enough 1543 00:54:49,480 --> 00:54:51,609 to have significant gravitational force. 1544 00:54:51,610 --> 00:54:53,320 This complicated 1545 00:54:54,400 --> 00:54:56,289 gravitational pull of all the millions of 1546 00:54:56,290 --> 00:54:58,809 stars among them 1547 00:54:58,810 --> 00:55:00,969 that acts like friction 1548 00:55:00,970 --> 00:55:03,069 and that this friction makes this 1549 00:55:03,070 --> 00:55:04,389 three dimensional bulb 1550 00:55:05,860 --> 00:55:08,359 kind of decay and fall back. 1551 00:55:08,360 --> 00:55:09,909 And the fact that there's angular 1552 00:55:09,910 --> 00:55:11,529 momentum that has to be conserved that 1553 00:55:11,530 --> 00:55:13,809 cannot be radiated off makes it actually 1554 00:55:13,810 --> 00:55:16,029 go into a disk because the disk is the 1555 00:55:16,030 --> 00:55:17,949 configuration with the given angle, the 1556 00:55:17,950 --> 00:55:19,540 momentum of the kind of lowest, 1557 00:55:20,620 --> 00:55:22,359 lowest energy. So if they don't retract 1558 00:55:22,360 --> 00:55:23,449 they, they don't do this. 1559 00:55:23,450 --> 00:55:24,699 They don't have the friction. 1560 00:55:24,700 --> 00:55:26,379 They would just fly around and orbits 1561 00:55:26,380 --> 00:55:26,499 like 1562 00:55:26,500 --> 00:55:27,459 they're used to, you say. 1563 00:55:27,460 --> 00:55:29,859 Gravity is not enough to build those 1564 00:55:31,030 --> 00:55:31,779 concentrations. 1565 00:55:31,780 --> 00:55:33,879 No, these because these are again, single 1566 00:55:33,880 --> 00:55:35,439 particles. I mean, they're they're tiny, 1567 00:55:35,440 --> 00:55:37,539 tiny particles. These are star stars 1568 00:55:37,540 --> 00:55:38,739 have significant gravity. 1569 00:55:38,740 --> 00:55:40,689 But these particles? 1570 00:55:40,690 --> 00:55:42,369 And shouldn't those supersymmetric 1571 00:55:42,370 --> 00:55:44,439 particles have affect to the 1572 00:55:44,440 --> 00:55:47,409 HAWKINS' radiation if they constantly? 1573 00:55:47,410 --> 00:55:47,829 So if you 1574 00:55:47,830 --> 00:55:49,899 have it in the in the I mean, hawking 1575 00:55:49,900 --> 00:55:51,299 radiation 1576 00:55:51,300 --> 00:55:53,499 we look at, it sounds like this 1577 00:55:53,500 --> 00:55:55,249 particular question needs to be taken. 1578 00:55:55,250 --> 00:55:57,009 OK, so let's go. 1579 00:55:57,010 --> 00:55:59,499 We'll take one answer is no, 1580 00:55:59,500 --> 00:56:00,500 no hawking radiation. 1581 00:56:01,810 --> 00:56:03,459 This is you. Remind me of my old physics 1582 00:56:03,460 --> 00:56:04,869 teacher at university. 1583 00:56:04,870 --> 00:56:05,870 No, you're wrong. 1584 00:56:06,670 --> 00:56:09,159 We'll take questions here from the VÉCU 1585 00:56:09,160 --> 00:56:10,160 here. 1586 00:56:10,750 --> 00:56:12,099 It's up to you. 1587 00:56:13,330 --> 00:56:15,619 It's my it's not my phone on. 1588 00:56:15,620 --> 00:56:17,199 I don't know about. 1589 00:56:17,200 --> 00:56:18,829 You just want to come forward to this. 1590 00:56:18,830 --> 00:56:19,209 No. No, it 1591 00:56:19,210 --> 00:56:20,210 works. 1592 00:56:20,620 --> 00:56:22,329 Works, OK? 1593 00:56:22,330 --> 00:56:24,579 I always thought the advantage of the 1594 00:56:24,580 --> 00:56:26,649 LHC is that we accelerate 1595 00:56:26,650 --> 00:56:27,759 protons. 1596 00:56:27,760 --> 00:56:29,829 And now you say, well, proton is 1597 00:56:29,830 --> 00:56:31,869 free quarks and a speck of dust on the 1598 00:56:31,870 --> 00:56:34,419 actual collision takes place between only 1599 00:56:34,420 --> 00:56:35,509 a small part of them. 1600 00:56:35,510 --> 00:56:37,479 So why didn't you establish the electrons 1601 00:56:37,480 --> 00:56:40,119 in the first place and accumulate 1602 00:56:40,120 --> 00:56:42,789 all the energy to this one, lepton? 1603 00:56:42,790 --> 00:56:44,859 Well, that was my first point that 1604 00:56:44,860 --> 00:56:46,809 was encoded in my answer. 1605 00:56:46,810 --> 00:56:48,789 It's that easy to accelerate. 1606 00:56:48,790 --> 00:56:50,469 Well, you can see you. 1607 00:56:50,470 --> 00:56:52,029 Well, the problem is you want to 1608 00:56:52,030 --> 00:56:53,799 accelerate them in the ring. 1609 00:56:53,800 --> 00:56:55,959 And the fact that 1610 00:56:55,960 --> 00:56:58,179 so people did that with the electrons 1611 00:56:58,180 --> 00:57:00,459 in the past, the predecessor left, 1612 00:57:00,460 --> 00:57:02,649 did this with electrons. 1613 00:57:02,650 --> 00:57:04,779 But the electrons, when you put them 1614 00:57:04,780 --> 00:57:07,119 on a circular orbit, they radiate 1615 00:57:07,120 --> 00:57:09,099 off electromagnetic waves, they lose 1616 00:57:09,100 --> 00:57:11,169 energy. Also, when you pull them on 1617 00:57:11,170 --> 00:57:13,329 the ring and they lose 1618 00:57:13,330 --> 00:57:15,399 more energy than you pump in by 1619 00:57:15,400 --> 00:57:17,529 the acceleration. So if 1620 00:57:17,530 --> 00:57:19,689 you want to accelerate electrons at these 1621 00:57:19,690 --> 00:57:21,189 high energies that cannot do this in a 1622 00:57:21,190 --> 00:57:23,170 ring, have to do this in a straight 1623 00:57:24,370 --> 00:57:26,619 accelerator called Linear Accelerate. 1624 00:57:26,620 --> 00:57:28,539 And actually, the next thing that 1625 00:57:28,540 --> 00:57:30,429 physicists would like to build is such a 1626 00:57:30,430 --> 00:57:32,919 linear accelerator that would be like 30 1627 00:57:32,920 --> 00:57:35,709 km pipes, 1628 00:57:35,710 --> 00:57:37,629 straight pipes colliding. 1629 00:57:37,630 --> 00:57:39,519 Actually, there was a proposal to build 1630 00:57:39,520 --> 00:57:42,099 one here at DC, so that would have reach 1631 00:57:42,100 --> 00:57:43,479 from pin it back. 1632 00:57:43,480 --> 00:57:46,029 I am torn to the DC 1633 00:57:46,030 --> 00:57:48,459 area in Bonn and then another 15 1634 00:57:48,460 --> 00:57:49,809 kilometers in the other direction. 1635 00:57:51,700 --> 00:57:53,139 Not small. 1636 00:57:53,140 --> 00:57:54,219 This gentleman here? 1637 00:57:54,220 --> 00:57:56,289 Yeah. In the diagram that is just 1638 00:57:56,290 --> 00:57:57,699 like next slide. 1639 00:57:57,700 --> 00:57:58,739 So you? 1640 00:57:59,800 --> 00:58:00,729 Yeah. Next one. 1641 00:58:00,730 --> 00:58:02,679 Yeah, this one, you just show like an 1642 00:58:02,680 --> 00:58:04,659 interaction with like supersymmetry 1643 00:58:04,660 --> 00:58:06,989 particle and you see that 1644 00:58:06,990 --> 00:58:09,040 there is like a neutrino like ejected 1645 00:58:10,060 --> 00:58:10,959 on the top. 1646 00:58:10,960 --> 00:58:13,089 Yeah, but couldn't we like see those 1647 00:58:13,090 --> 00:58:15,369 neutrinos who like, detect them somehow? 1648 00:58:15,370 --> 00:58:17,439 No, we don't see them as well. 1649 00:58:17,440 --> 00:58:19,689 OK, so they haven't been seen 1650 00:58:19,690 --> 00:58:20,649 or like. 1651 00:58:20,650 --> 00:58:22,599 Well, I mean, not in a particle and not 1652 00:58:22,600 --> 00:58:23,919 in such a particle detector. 1653 00:58:23,920 --> 00:58:25,329 They are detectors for neutrinos, but 1654 00:58:25,330 --> 00:58:26,529 they are completely, completely 1655 00:58:26,530 --> 00:58:27,489 different. Yeah. No, I don't. 1656 00:58:27,490 --> 00:58:29,379 But we could like have like some 1657 00:58:29,380 --> 00:58:31,329 somewhere in the Earth, and we would like 1658 00:58:31,330 --> 00:58:33,399 to see them coming from like those points 1659 00:58:33,400 --> 00:58:34,749 in the galaxy or somewhere. 1660 00:58:34,750 --> 00:58:37,089 So like seeing an excess 1661 00:58:37,090 --> 00:58:38,829 of neutrino? 1662 00:58:38,830 --> 00:58:40,479 Yeah. But. Remember, you're creating just 1663 00:58:40,480 --> 00:58:41,379 one. 1664 00:58:41,380 --> 00:58:42,380 Yeah. 1665 00:58:42,850 --> 00:58:44,559 Compared to like the song, it's enough to 1666 00:58:44,560 --> 00:58:45,049 detect you. 1667 00:58:45,050 --> 00:58:46,149 Yeah, yeah. 1668 00:58:46,150 --> 00:58:48,459 OK, so we're just about out of time 1669 00:58:48,460 --> 00:58:49,779 here. Do we have any questions from the 1670 00:58:49,780 --> 00:58:50,889 internet? 1671 00:58:50,890 --> 00:58:51,699 No. OK. 1672 00:58:51,700 --> 00:58:53,379 Maybe this lady in the back. 1673 00:58:53,380 --> 00:58:55,089 Yeah, OK. We'll take one more here for 1674 00:58:55,090 --> 00:58:56,890 this lady, and then I'll call it quits. 1675 00:58:58,600 --> 00:59:00,609 OK, I have no clue, and I tried to get a 1676 00:59:00,610 --> 00:59:02,919 basic understanding of this dark matter 1677 00:59:02,920 --> 00:59:05,319 concept. So as 1678 00:59:05,320 --> 00:59:06,850 I understood it, it had 1679 00:59:08,410 --> 00:59:09,459 there should be mass. 1680 00:59:09,460 --> 00:59:11,889 But this there is nothing that emits 1681 00:59:11,890 --> 00:59:13,269 anything that we could measure. 1682 00:59:13,270 --> 00:59:14,079 Is that right? 1683 00:59:14,080 --> 00:59:15,699 Well, that we see, I mean, we just see 1684 00:59:15,700 --> 00:59:18,009 light. So we only see stuff that emits 1685 00:59:18,010 --> 00:59:20,409 light, namely stars. 1686 00:59:20,410 --> 00:59:21,410 OK, what is light? 1687 00:59:22,480 --> 00:59:24,609 Oh, that's a complicated light. 1688 00:59:24,610 --> 00:59:26,679 So light. I mean, when you look at it, 1689 00:59:26,680 --> 00:59:27,929 I mean, go outside. 1690 00:59:27,930 --> 00:59:30,009 No clouds stars. 1691 00:59:30,010 --> 00:59:31,480 You see the light from the stars. 1692 00:59:32,690 --> 00:59:34,209 So that's what we see. 1693 00:59:34,210 --> 00:59:35,589 I mean, that's our information about the 1694 00:59:35,590 --> 00:59:37,389 galaxy, the light from the stars that 1695 00:59:37,390 --> 00:59:38,439 reaches us. 1696 00:59:38,440 --> 00:59:40,329 And this comes from stars and we know 1697 00:59:40,330 --> 00:59:41,799 what stars are made out of. 1698 00:59:41,800 --> 00:59:43,569 OK, so it's only light. 1699 00:59:43,570 --> 00:59:44,570 Yeah, OK. 1700 00:59:45,640 --> 00:59:46,640 OK, thanks. 1701 00:59:50,010 --> 00:59:51,059 OK. 1702 00:59:51,060 --> 00:59:53,459 Was that do you feel appropriately 1703 00:59:53,460 --> 00:59:54,460 enlightened, 1704 00:59:56,980 --> 00:59:59,309 come to me afterwards, and maybe I can 1705 00:59:59,310 --> 01:00:00,569 give you a longer version of 1706 01:00:00,570 --> 01:00:02,669 the Sense, OK? Well, this if 1707 01:00:02,670 --> 01:00:05,159 there are any further questions, 1708 01:00:05,160 --> 01:00:06,869 Dr. Helling will take up cheerfully. 1709 01:00:06,870 --> 01:00:09,029 Take your questions in the lounge 1710 01:00:09,030 --> 01:00:10,049 so I can place it. 1711 01:00:10,050 --> 01:00:11,399 No, that's too loud. 1712 01:00:11,400 --> 01:00:12,429 That's a lot. 1713 01:00:12,430 --> 01:00:14,819 I just thought that all this probably 1714 01:00:14,820 --> 01:00:17,129 also neatly explains why 1715 01:00:17,130 --> 01:00:18,269 I failed. 1716 01:00:18,270 --> 01:00:20,639 Q Can I try to 1717 01:00:20,640 --> 01:00:22,979 find out? About 20 some odd years ago, 1718 01:00:22,980 --> 01:00:23,980 it was embarrassing. 1719 01:00:24,960 --> 01:00:26,099 Thank you very much. 1720 01:00:26,100 --> 01:00:27,479 They can't focus, please.