0 00:00:02,460 --> 00:00:07,589 Jorge Pullin: These words speaker to this manuscript to speak about the search for a tabletop quantum gravity signature. 1 00:00:10,530 --> 00:00:11,490 Christodoulou Marios: Thank you very much. 2 00:00:13,230 --> 00:00:16,800 Christodoulou Marios: Thank you very much for the invitation it's very nice to be back. 3 00:00:17,970 --> 00:00:31,680 Christodoulou Marios: So many people that I haven't seen for some time i've tried to make the seminar interesting as an overview of things i've been thinking about and learned the past few years. 4 00:00:32,820 --> 00:00:35,190 Christodoulou Marios: I realized that my title was a bit too ambitious. 5 00:00:36,330 --> 00:00:40,530 Christodoulou Marios: I wasn't able to feed the many things that are happening, so this is a very personalized. 6 00:00:42,030 --> 00:00:50,220 Christodoulou Marios: selection and of topics around the search for a table top quantum gravity signature. 7 00:00:52,620 --> 00:01:07,650 Christodoulou Marios: So, to give you a quick overview weather will say because I didn't put them took outline i'll start with a, I will start with a short historical note, I give you a summary of some experimental news that you may you may be interested to them with an expert in distinct. 8 00:01:08,970 --> 00:01:19,800 Christodoulou Marios: A quick overview overview of one set up for detecting gravity limited entanglement, which is the simplest conceptually and which I will analyze in the last part. 9 00:01:21,390 --> 00:01:25,230 Christodoulou Marios: And first give an overview of the debate and some confusion, then I will. 10 00:01:26,910 --> 00:01:32,070 Christodoulou Marios: analyze this setup based on our various and paper and take you through it. 11 00:01:33,480 --> 00:01:38,670 Christodoulou Marios: And then finish with a short discussion, these are our small parts. 12 00:01:40,230 --> 00:01:44,160 Christodoulou Marios: The several small parts to talk all right let's start. 13 00:01:45,510 --> 00:01:48,060 Christodoulou Marios: So, first of all, historical note. 14 00:01:49,770 --> 00:01:51,480 Christodoulou Marios: There idea will be talking about. 15 00:01:53,820 --> 00:02:02,520 Christodoulou Marios: detecting entanglement the generated by gravity is not a new idea at all them people have inside the Chapel hill conference. 16 00:02:04,170 --> 00:02:13,110 Christodoulou Marios: Where reject rain man, this is a selection of course that i'm taking from this paper, which is very nice paper from our point of different experimentalists. 17 00:02:14,190 --> 00:02:16,770 Christodoulou Marios: An sc that came out very recently. 18 00:02:18,180 --> 00:02:24,720 Christodoulou Marios: we're in trouble, and it will be live in quantum mechanics been done coindesk of additional theory, one should think about Designing an experiment. 19 00:02:25,320 --> 00:02:35,250 Christodoulou Marios: which uses a gravitational link and at the same time, shows quantum interference, I find very interesting that trace of war of words here, we already alluded to some. 20 00:02:36,300 --> 00:02:37,590 Christodoulou Marios: quantum from patient. 21 00:02:39,120 --> 00:02:44,220 Christodoulou Marios: idea that you wanted wanted practice and bass will come back to that later. 22 00:02:46,650 --> 00:02:53,520 Christodoulou Marios: So there is an exchange where we wheaton asks what prevents this from becoming a practical experiment. 23 00:02:54,420 --> 00:03:01,410 Christodoulou Marios: And Richard feynman says, you might argue this way somewhere in your part to this idea of credibility amplitude has been lost. 24 00:03:02,160 --> 00:03:17,520 Christodoulou Marios: You do not need it anymore, so you drop it the wave packet would be reduced or something even though you don't know where it's reduced it's reduced, and then you can do an experiment which distinguishes interfering alternatives from just plain odds like with dice. 25 00:03:18,780 --> 00:03:30,060 Christodoulou Marios: That since a very good summary of everything I will talk about a modern parlance gravity media to tangle meant would see to acquire a contest gravitational field and. 26 00:03:30,840 --> 00:03:41,790 Christodoulou Marios: Then travel from realizing such an experiment is the coherence, environment, which implies that the outcomes of measurements on the probe probe will be described by probabilistic nature. 27 00:03:42,510 --> 00:03:52,920 Christodoulou Marios: 63 years later, this is roughly still the state of affairs just that we may realistically hope to see this experiment done within a generation which could not have been said in 1957. 28 00:03:53,640 --> 00:04:03,180 Christodoulou Marios: So with regards to the experimental status, this is and what is the main difficulty, this is the situation is to go Harris, the main difficulty. 29 00:04:06,090 --> 00:04:09,150 Christodoulou Marios: Not only, but this is really that difficult thing. 30 00:04:11,970 --> 00:04:14,070 Christodoulou Marios: And with respect to theory where's the. 31 00:04:15,150 --> 00:04:19,980 Christodoulou Marios: here to what degree, is this an accurate statement or not. 32 00:04:24,180 --> 00:04:26,280 Christodoulou Marios: Alright, so. 33 00:04:27,330 --> 00:04:35,220 Christodoulou Marios: This is an animation that they took from this magazine, which is not working here my iPad but you should be able to see it on the slides. 34 00:04:37,680 --> 00:04:40,800 Christodoulou Marios: i'm going to the overview of what's going on experimental. 35 00:04:42,450 --> 00:04:45,810 Christodoulou Marios: And why there is excitement around. 36 00:04:47,100 --> 00:04:56,250 Christodoulou Marios: The possibility to sequential grabbing the table to experiment and what is my understanding from having discussed with people that actually understand these things. 37 00:04:58,980 --> 00:05:01,890 Christodoulou Marios: On what is justified and what is not justified. 38 00:05:04,050 --> 00:05:04,620 Christodoulou Marios: So. 39 00:05:06,480 --> 00:05:15,210 Christodoulou Marios: To give you some history, the song maybe we can say that they started with these efforts by zeilinger and aren't. 40 00:05:16,740 --> 00:05:23,130 Christodoulou Marios: Excuse me here this paper, where they are so interference patterns, by passing. 41 00:05:24,300 --> 00:05:27,450 Christodoulou Marios: project called listings back tubers from great things. 42 00:05:28,620 --> 00:05:42,150 Christodoulou Marios: And within 20 years let's say they went up for orders of magnitude to 10 to the minus 20 kilos this would be the most efficient way to create a separation, with just one of the main things need. 43 00:05:43,830 --> 00:05:45,930 Christodoulou Marios: To create a microscopic preposition. 44 00:05:47,100 --> 00:05:58,080 Christodoulou Marios: But apparently This cannot, they cannot push it very much because there is the issue that, in order to proceed to fear as as you increase the mass, you have to put the screen further away. 45 00:05:58,770 --> 00:06:12,300 Christodoulou Marios: And to to go to scales, where it becomes interesting, you will need to have the meters, and this will be free for so you need to dig a hole of hundred meters and let the things fall into the experiment there, which is just impractical. 46 00:06:15,870 --> 00:06:17,130 Christodoulou Marios: That is at least. 47 00:06:18,360 --> 00:06:28,200 Christodoulou Marios: What everything i'm telling you is mainly coming from Marcus a discussion with microsoft's been mayor and his team, who is the director here in the very good experimentalists. 48 00:06:31,500 --> 00:06:32,220 Christodoulou Marios: Now. 49 00:06:33,990 --> 00:06:50,010 Christodoulou Marios: There is another type of techniques which is based on quantum levitation and optical cooling where they levitate particles now they're at nanoparticles and then with lasers, they can extract energy and put them in the ground state. 50 00:06:51,600 --> 00:07:08,370 Christodoulou Marios: Much of the excitement's is around these developments, because they've already been at 10 to the minus 18 which is orders of magnitude above the previous technique and there are claims that this, there will be rapid progress and even within a couple of years, it can go up by. 51 00:07:12,870 --> 00:07:14,190 Christodoulou Marios: Six orders of magnitude. 52 00:07:19,830 --> 00:07:34,860 Christodoulou Marios: yeah these are two papers that have made some noise lately, so I mean don't ask me the details of what's going on, but this thing here is the laser that is pushing the particle up and keeping it there. 53 00:07:35,910 --> 00:07:46,170 Christodoulou Marios: And levitating it and this other eight lasers, which I think that's why you see the reflection that do measurement next do the cooling and then also the measurements to see. 54 00:07:47,520 --> 00:08:00,600 Christodoulou Marios: They mainly do X and T measurements, to see that you said to date there as positioning momentum to see that the Heisenberg uncertainty saturated and from this, then they can. 55 00:08:02,640 --> 00:08:18,960 Christodoulou Marios: They can do the so called sidebars measurements, from where they can expect the temperature in DC that is close to absolute zero so in a sense, it's still classical you what they can infer that it must be in its ground state, but there is no measure of currents, in that sense. 56 00:08:23,280 --> 00:08:23,790 Christodoulou Marios: All right. 57 00:08:25,020 --> 00:08:40,320 Christodoulou Marios: That is one side of the story, the quantum story, then, on the other side of the story, so the experiments, I talked about both of the pictures they gave those are done in Vienna, and also in Vienna, there is this. 58 00:08:41,610 --> 00:08:45,600 Christodoulou Marios: Other side of the story, which is procedural gravity measurements. 59 00:08:46,650 --> 00:08:58,050 Christodoulou Marios: Now, what is being done here is trying to measure the gravitational field of smaller and smaller masses the the record is from paper. 60 00:09:01,590 --> 00:09:12,420 Christodoulou Marios: Which is between my it's the measurement of the gravitational field of a mass lady said 10 to the minus five kilos it's this mass here it's a passionate pendulum. 61 00:09:13,500 --> 00:09:15,900 Christodoulou Marios: That they modulate and then they can extract. 62 00:09:17,130 --> 00:09:22,860 Christodoulou Marios: From that the signal of the gravitational attraction then we'll look back and forth and. 63 00:09:23,880 --> 00:09:25,290 Christodoulou Marios: This thing is. 64 00:09:26,910 --> 00:09:29,070 Christodoulou Marios: torsion or pendulum This is just. 65 00:09:31,020 --> 00:09:37,290 Christodoulou Marios: A piece of metal to the prudential screen that electromagnetic interaction, which they move to take a foot. 66 00:09:38,730 --> 00:09:43,530 Abhay Vasant Ashtekar: In this case, just measuring the acceleration to drive again, not the type of forces I begin. 67 00:09:43,530 --> 00:09:44,790 Abhay Vasant Ashtekar: particles like that right. 68 00:09:45,060 --> 00:09:45,330 Yes. 69 00:09:47,100 --> 00:09:47,280 Abhay Vasant Ashtekar: Yes. 70 00:09:47,700 --> 00:09:48,900 Abhay Vasant Ashtekar: Yes, yes. 71 00:09:48,990 --> 00:09:50,010 Christodoulou Marios: they're not measuring. 72 00:09:50,010 --> 00:09:50,640 degrading. 73 00:09:52,140 --> 00:09:52,320 Over. 74 00:09:55,020 --> 00:09:56,850 Christodoulou Marios: This is really newtonian force measured. 75 00:09:57,540 --> 00:09:57,780 yell. 76 00:09:59,430 --> 00:10:06,450 Christodoulou Marios: At them I don't I don't think this type they're even thinking of going to send think took to measure Cambridge. 77 00:10:08,730 --> 00:10:24,150 Christodoulou Marios: Now, where they put these photos because there's one question somewhere to be skeptical about what I was saying that the next slide that they're claiming that there's gonna be a lot of improvement, and you know one question is why the soon. 78 00:10:25,590 --> 00:10:32,220 Christodoulou Marios: Basically, because it's just the beginning and now they're getting attention and more funding and resources. 79 00:10:33,300 --> 00:10:49,290 Christodoulou Marios: This a big part of that comes down to simple engineering tasks like doing precision engineering that they have a lab here, creating down to item precision of things, but there's also simply the location, so this experiment, they did it here in Vienna. 80 00:10:50,520 --> 00:10:55,500 Christodoulou Marios: The problem that they were picking up the gravity of the trump just so happens that the term that is passing. 81 00:10:56,010 --> 00:11:00,660 Christodoulou Marios: Like 200 meters from here would give exactly the same feet as passing every five minutes. 82 00:11:01,440 --> 00:11:11,340 Christodoulou Marios: Was destroying all their signal and they were only doing measurement between two and six, when it was not run so now they've given them a sport in this channel where. 83 00:11:11,910 --> 00:11:19,170 Christodoulou Marios: The European Space agency's also doing some experiments with a domino off and just from the fact that they move it and purposes, this. 84 00:11:20,100 --> 00:11:28,740 Christodoulou Marios: it's you see that this really just the box and they got directly three orders of magnitude just because the noise went away without even. 85 00:11:29,400 --> 00:11:39,030 Christodoulou Marios: Improvement of the setup and it's going to be the same for the quantum stuff they will they're trying to also put them in the panel, so there are six pairs of mechanism to get for free for the location. 86 00:11:39,810 --> 00:11:58,890 Christodoulou Marios: So this explains a bit to the hype and the possible excitement that you might hear in the coming years that basically now what's going on is on the quantum side that what I said in the beginning, but the quantum side but putting the ground state and microscopic creatures matter. 87 00:12:00,090 --> 00:12:14,280 Christodoulou Marios: Where now here to manage the two kilos the precision gravity measurements are here and they're claiming that within a few years, we will be here to the minus plus or minus nine and by the end of the decade, maybe we get the numbers. 88 00:12:16,140 --> 00:12:20,910 Christodoulou Marios: Right so that's why it's exciting and it is. 89 00:12:22,290 --> 00:12:23,460 Christodoulou Marios: But there is. 90 00:12:24,780 --> 00:12:30,630 Christodoulou Marios: Just to be clear and they think in this paper marquesas very honest about the situation. 91 00:12:31,800 --> 00:12:47,670 Christodoulou Marios: This is, you know, since the end of it, the big challenges are actually to create a macroscopic preposition which they don't really know they're thinking about it, how they're going to do it even that double sleep type doesn't work. 92 00:12:48,690 --> 00:12:51,210 Christodoulou Marios: Of course, the keep the coherence long enough. 93 00:12:52,740 --> 00:12:58,230 Christodoulou Marios: And then you have to think of an experiment that has both. 94 00:12:59,700 --> 00:13:08,790 Christodoulou Marios: Does both you can both have a quantum matter that they sent me from rotation, that you can keep the coherence along and you can do precision very the measurements. 95 00:13:09,090 --> 00:13:16,680 Christodoulou Marios: And this is completely open really there's ideas coming every week about what to do and what both and experience it on the theoretical side. 96 00:13:17,940 --> 00:13:27,930 Christodoulou Marios: What is interesting for us traditions that there is there is experimental races will definitely continue, and there is a lot of momentum it say. 97 00:13:28,530 --> 00:13:42,000 Christodoulou Marios: On the other side, there is, you know the horizon, maybe 20 years, who knows, so there is a part of the race of thinking of smarter measurements So what exactly do we want to measure. 98 00:13:44,340 --> 00:13:46,140 Christodoulou Marios: Is there a smarter experiment to do. 99 00:13:50,280 --> 00:13:52,200 Christodoulou Marios: All right now I will. 100 00:13:53,250 --> 00:14:07,410 Christodoulou Marios: confuse you a bit because i've been talking about the traps and I will change to a different setup which, however, is the same physics so rather than having you know what I was talking before you would have potentials. 101 00:14:09,060 --> 00:14:14,940 Christodoulou Marios: let's say harmonic potentials where you would trap away function, and this would be your mass. 102 00:14:16,050 --> 00:14:24,300 Christodoulou Marios: And these two would interact and this would create an gravitation early through some type of interaction that would call like. 103 00:14:28,620 --> 00:14:31,020 Christodoulou Marios: write it from all right. 104 00:14:34,110 --> 00:14:35,820 Christodoulou Marios: Sorry, this would be a small team. 105 00:14:44,520 --> 00:14:48,840 Christodoulou Marios: But an equivalent, at least, it seems that the equivalent people. 106 00:14:50,100 --> 00:14:51,660 Christodoulou Marios: saved 100 shown it. 107 00:14:52,710 --> 00:14:58,710 Christodoulou Marios: Another way to think of gravity mated the document would just conceptually much simpler. 108 00:15:00,330 --> 00:15:09,240 Christodoulou Marios: He says, for those this is based on this paper, the setup was proposed in this paper, the setup with a traps was proposed on this paper. 109 00:15:12,660 --> 00:15:17,070 Christodoulou Marios: And this one is with my Center which is completely in Principle number. 110 00:15:20,520 --> 00:15:26,640 Christodoulou Marios: So this is the end V centers where what you do is that you imagine you have two masses. 111 00:15:29,370 --> 00:15:33,240 Christodoulou Marios: In which you embed the spin degree of freedom, a single speaker freedom. 112 00:15:34,560 --> 00:15:39,060 Christodoulou Marios: they're talking specifically about energy centers which are used to quantum computing to create cubits. 113 00:15:40,740 --> 00:15:45,810 Christodoulou Marios: You manipulate the spin you said it in superposition in up and down let's say. 114 00:15:48,690 --> 00:15:50,820 Christodoulou Marios: Initially it's a non untangled state. 115 00:15:55,650 --> 00:16:00,000 Christodoulou Marios: You prepare it in a non untangle state set it up and down and. 116 00:16:01,020 --> 00:16:09,330 Christodoulou Marios: Then you pass it through a reversible stern Gary like type of parameters and, at the end you do measurements on the speeds. 117 00:16:11,490 --> 00:16:15,150 Christodoulou Marios: So that to myself that in the past position by manipulating their. 118 00:16:16,350 --> 00:16:17,700 Christodoulou Marios: spin through magnetic field. 119 00:16:19,410 --> 00:16:24,270 Christodoulou Marios: There initially load the town called the, you have the distance D amp T. 120 00:16:26,640 --> 00:16:29,430 Christodoulou Marios: i'm putting just a branch of close the post here. 121 00:16:30,900 --> 00:16:41,760 Christodoulou Marios: Because I will give some formulas afterwards we're enabling the gravity in all other branch just for simplicity, then we will say much more general division of what's going on here. 122 00:16:44,550 --> 00:16:46,800 Christodoulou Marios: The idea was to leave them to freefall. 123 00:16:48,930 --> 00:16:57,540 Christodoulou Marios: And then you'd measurements of the screens if the speeds become entangled I mean theater of interaction must be able to query quantum information. 124 00:16:58,560 --> 00:17:05,640 Christodoulou Marios: The mediator, is a gravitational field, and does it cannot be class questions, so this is basically the agreement that appeared in these two papers. 125 00:17:07,980 --> 00:17:08,970 Christodoulou Marios: Huge debate. 126 00:17:10,740 --> 00:17:23,730 Christodoulou Marios: ensued into a lot of development and many new ideas on how to do this, both on the feasibility side Now I will turn to the conceptual part, the more theoretical part. 127 00:17:25,680 --> 00:17:28,980 Christodoulou Marios: I should say this is again, this is a very select the. 128 00:17:30,450 --> 00:17:35,880 Christodoulou Marios: Small selection of the literature this papers, I said at 400 times each now so. 129 00:17:38,970 --> 00:17:42,900 Christodoulou Marios: Yes, this is mainly the the references that they. 130 00:17:44,040 --> 00:17:45,090 Christodoulou Marios: more interested in. 131 00:17:46,620 --> 00:17:55,440 Christodoulou Marios: This a bit more in yes it's again explaining them I am again explaining them the phenomenon. 132 00:17:56,730 --> 00:17:59,910 Christodoulou Marios: What happens is that you start non in a separate apple state. 133 00:18:01,200 --> 00:18:13,830 Christodoulou Marios: you end up in a tangled state the simplest way to see this is imagine that you neglect the gravitational attraction in all branches, but this one, where they are closest, then you will get a face. 134 00:18:14,940 --> 00:18:22,410 Christodoulou Marios: And everything like that the phases here because they're much smaller than this one now if this face is not zero then it's non zero entanglement. 135 00:18:23,490 --> 00:18:26,910 Christodoulou Marios: There is a type of protection, you went from say purple to entangled state. 136 00:18:28,050 --> 00:18:43,320 Christodoulou Marios: And then that's something must have mediated least entanglement there's nothing that here you've made sure it's not the electromagnetic field, so it must have been the gravitational field, and thus it must be carrying quantum information and last name of the class. 137 00:18:44,730 --> 00:18:48,030 Christodoulou Marios: That is their story, they are, and so their argument goes. 138 00:18:51,870 --> 00:18:54,750 Christodoulou Marios: Right now, in terms of how this was described. 139 00:18:56,430 --> 00:19:03,900 Christodoulou Marios: You know from gravity, they were initially people were just using basically the the neutrons formula we learned in high school. 140 00:19:05,010 --> 00:19:13,560 Christodoulou Marios: For the gravitational energy which you plug in in the face times time developed H bar and this gives you the quantum face. 141 00:19:16,890 --> 00:19:27,630 Christodoulou Marios: These formulas are just used to determine what are the parameters you're going to need master time and D, initially in the experimental proposals and then assuming a local interaction. 142 00:19:28,680 --> 00:19:31,110 Christodoulou Marios: On top you can make this argument that. 143 00:19:32,160 --> 00:19:33,930 Christodoulou Marios: The gravitational field cannot be classical. 144 00:19:35,670 --> 00:19:39,270 Christodoulou Marios: Now this created huge confusion. 145 00:19:40,650 --> 00:19:50,490 Christodoulou Marios: And discussion on what exactly is there to be claimed if we see this phenomenon i'll give you a few points of view. 146 00:19:54,750 --> 00:19:56,640 Christodoulou Marios: First of all, there is the side, where. 147 00:19:57,870 --> 00:20:05,850 Christodoulou Marios: People say there is this has nothing to do with quantum gravity it's agnostic to the quantum of classical nature of the two degrees of freedom. 148 00:20:06,270 --> 00:20:20,100 Christodoulou Marios: does not involve two degrees of freedom, this is, this was a Comet that appeared in this two papers that were publishing period, it was a pure comment period very soon after this is a much more detailed analysis. 149 00:20:23,490 --> 00:20:23,820 Christodoulou Marios: In. 150 00:20:25,500 --> 00:20:27,750 Christodoulou Marios: claiming to be non paratrooper that but not really. 151 00:20:30,660 --> 00:20:33,510 Christodoulou Marios: Where essentially what's been gone is that they do the usual. 152 00:20:34,890 --> 00:20:39,960 Christodoulou Marios: splitting of the gravitational field into a Colombian part of transfers part. 153 00:20:40,860 --> 00:20:53,280 Christodoulou Marios: And then they neglect the transfer this say Lucas just a Columbia part of is not decrease the freedom equals i'm doing a very unfair summary it's a big paper, but this will be familiar for my name is Melissa too many of you. 154 00:20:54,420 --> 00:20:54,930 Christodoulou Marios: There is. 155 00:20:57,000 --> 00:21:00,630 Christodoulou Marios: on the opposite side, there is a claim that it implies detection of visual gravity. 156 00:21:01,920 --> 00:21:03,240 Christodoulou Marios: Which is. 157 00:21:05,040 --> 00:21:09,780 Christodoulou Marios: Very exaggerated, in my opinion it is problematic because two of the people. 158 00:21:11,580 --> 00:21:17,670 Christodoulou Marios: suggesting this mazumdar and both are two are the two main office of. 159 00:21:19,230 --> 00:21:21,150 Christodoulou Marios: Of of the whole idea. 160 00:21:22,350 --> 00:21:33,900 Christodoulou Marios: Of the paper that proposed the setup that I just explained, which also has more detailed feasibility study and the better entanglement witness it's more detail. 161 00:21:35,880 --> 00:21:39,540 Christodoulou Marios: Now, their claims are based on doing the analysis in the quantum field theory. 162 00:21:41,280 --> 00:21:54,510 Christodoulou Marios: In a canonical setting in the hamiltonian setting and showing that you can get the the description of the phenomenon by expressing the newtonian potential as visual gravitas essentially. 163 00:21:56,430 --> 00:22:06,060 Christodoulou Marios: identity as a claim is, in my opinion, very exaggerated, because this doesn't show anything that point is that you can also describe the phenomenon without using that, which is what we will see. 164 00:22:08,940 --> 00:22:12,990 Christodoulou Marios: So these are the two extremes, for me, nothing to do with quantum gravity vitriol gravity payments. 165 00:22:14,610 --> 00:22:27,120 Christodoulou Marios: Of course the question would be a bit, first of all, you see gravitas before you think about future gravitas and done or this middle ground there is. 166 00:22:28,320 --> 00:22:40,170 Christodoulou Marios: I don't know if I should be calling them to points of view, maybe to be done, fair, because there is another level, so in the authors, but there is this let's say isolation between what to say. 167 00:22:41,340 --> 00:22:44,490 Christodoulou Marios: There is a diagnostic statement that. 168 00:22:46,770 --> 00:22:53,850 Christodoulou Marios: Seeing induced entanglement would imply that quantum formations carried by the non relative part whatever you want to mean by that. 169 00:22:55,800 --> 00:22:59,280 Christodoulou Marios: which are mainly mainly coming from these papers here. 170 00:23:02,490 --> 00:23:05,580 Christodoulou Marios: And Bob file the, which is the Co authors here. 171 00:23:06,600 --> 00:23:16,530 Christodoulou Marios: has recently put out another paper, two years later, where he's getting a bit from the more careful statements that were being made here. 172 00:23:17,160 --> 00:23:22,500 Christodoulou Marios: And they're saying you're trying to untangle mud mud is you doesn't play any the existence of the gravity there. 173 00:23:23,340 --> 00:23:34,620 Christodoulou Marios: To to save these they're using smart argument that's coming from this papers which, if I have time and you're interested, they could go a bit into but it's it's it's a bit of a convoluted story. 174 00:23:37,860 --> 00:23:42,720 Christodoulou Marios: And one issues that everybody's doing them in their own firm, and this is seen. 175 00:23:45,540 --> 00:23:51,090 Christodoulou Marios: In kirsty in Cap space same language essentially using the client Gordon. 176 00:23:52,260 --> 00:23:54,660 Christodoulou Marios: Inner product properties. 177 00:23:55,950 --> 00:23:56,610 Christodoulou Marios: This is seen. 178 00:23:57,720 --> 00:24:17,670 Christodoulou Marios: As matrix for management which ones are more contact information, this one is more to 50 years and current state and, yes, there is this lively debate, which I heard that that's going to put out a paper today or yesterday which I haven't read criticizing these papers that are wrong. 179 00:24:20,850 --> 00:24:24,090 Christodoulou Marios: All right now the middle ground that I have been. 180 00:24:26,280 --> 00:24:26,940 Christodoulou Marios: Settling. 181 00:24:28,650 --> 00:24:31,410 Christodoulou Marios: To personally is that. 182 00:24:32,850 --> 00:24:38,640 Christodoulou Marios: What we might say is that is affected texts, a microscopic proposition of space time essentially the existence of. 183 00:24:40,770 --> 00:24:44,580 Christodoulou Marios: Two positions of some classical states in the state space of. 184 00:24:45,780 --> 00:24:48,360 Christodoulou Marios: The theory that describes this low energy regime. 185 00:24:49,950 --> 00:24:56,340 Christodoulou Marios: And I would like to qualify that even further, but should do this first cover some more crowd. 186 00:24:59,610 --> 00:25:09,840 Christodoulou Marios: So now, I will talk about this latest paper and take you through the calculation is nothing fancy and complicated and discuss a bit at the end what our conclusions. 187 00:25:11,190 --> 00:25:16,950 Christodoulou Marios: Are the me read the the the the physical intuition conclusion. 188 00:25:18,990 --> 00:25:26,280 Christodoulou Marios: So the physical picture arising from the analysis that information travels in the quantum superposition of field with France. 189 00:25:26,850 --> 00:25:35,940 Christodoulou Marios: And mechanism that propagates the quantum information with the speed of light is a quantum superposition of microscopically this thing then i'm going to feel comfortable. 190 00:25:38,100 --> 00:25:41,670 Abhay Vasant Ashtekar: Getting alicia What do you mean by field vacations in. 191 00:25:41,790 --> 00:25:49,050 Christodoulou Marios: In gravity and so I will spend the next four slides making more clear. 192 00:25:50,370 --> 00:25:51,780 Christodoulou Marios: I mean, this is just the words. 193 00:25:51,810 --> 00:25:53,250 Christodoulou Marios: Right now, this is just physical to. 194 00:25:55,500 --> 00:25:58,560 Christodoulou Marios: Their their technical conclusion is not this. 195 00:26:01,290 --> 00:26:05,190 Christodoulou Marios: But I hope for this intuition, we can discuss it, too, because actually. 196 00:26:07,260 --> 00:26:13,350 Christodoulou Marios: 80% sure I put them dish so all right, this is a setup. 197 00:26:16,200 --> 00:26:21,420 Christodoulou Marios: We imagine there is a partition function, this is heuristics on up to this. 198 00:26:23,010 --> 00:26:30,150 Christodoulou Marios: So this is really just say imagine there is a path integral where these are they. 199 00:26:32,580 --> 00:26:39,630 Christodoulou Marios: The paths, so you remember, I should have put a figure here i'm referring referring always to. 200 00:26:41,100 --> 00:26:57,840 Christodoulou Marios: A situation like these, although the formula is is applicable to arbitrary paths and arbitrary number of particles, so the X is paths of particles point particles, we will take. 201 00:26:58,860 --> 00:27:00,390 Christodoulou Marios: In a bit in particular. 202 00:27:03,330 --> 00:27:10,170 Christodoulou Marios: What here, then the practical some confusion i'm sorry, so this is the paths degrees of freedom, and this is a field degree of freedom. 203 00:27:12,210 --> 00:27:14,730 Christodoulou Marios: Now the action is and. 204 00:27:15,840 --> 00:27:36,660 Christodoulou Marios: Then ethical variables are the paths labeled by a for the number of particles and F is the field by field, what I mean, in particular, is for electron electromagnetism the vector potential and for leaner is gravity the metric perturbation we just put it as F, because we took those places. 205 00:27:38,730 --> 00:27:40,740 Christodoulou Marios: in one go because they're very similar. 206 00:27:43,590 --> 00:27:48,180 Christodoulou Marios: All right, and then there is the mass there is a magnetic field, there is the spin configurations. 207 00:27:49,740 --> 00:27:52,770 Christodoulou Marios: Where the spin configurations are. 208 00:27:54,510 --> 00:28:02,640 Christodoulou Marios: The tensor product over the individual spins that are embedded in these particles. 209 00:28:04,890 --> 00:28:05,400 Christodoulou Marios: All right. 210 00:28:08,670 --> 00:28:23,670 Christodoulou Marios: We imagine there are some semi classical states that we will use to fold this partition function this path integral devolution an operator that gives the evolution from here to here would be. 211 00:28:25,050 --> 00:28:32,400 Christodoulou Marios: given by would be over this form, because this is simply because the spins do not. 212 00:28:33,570 --> 00:28:41,010 Christodoulou Marios: Change along the path So these are somehow external degrees of freedom manipulated by these external feet. 213 00:28:42,300 --> 00:28:44,910 Christodoulou Marios: So your evolution of PR we split in this form. 214 00:28:45,960 --> 00:28:47,400 Christodoulou Marios: Then we take a. 215 00:28:48,720 --> 00:28:49,170 Christodoulou Marios: tool. 216 00:28:50,640 --> 00:28:54,330 Christodoulou Marios: Simple approximations with take the field to be on Shell. 217 00:28:56,850 --> 00:29:01,170 Christodoulou Marios: So the field now is on shed in the sense that it satisfies. 218 00:29:02,460 --> 00:29:04,020 Christodoulou Marios: The field equations. 219 00:29:05,430 --> 00:29:08,430 Christodoulou Marios: For particles with trajectories. 220 00:29:09,690 --> 00:29:10,470 Christodoulou Marios: X. 221 00:29:15,600 --> 00:29:27,450 Christodoulou Marios: And then the integral over the paths can be performed by simply assuming that their paths are nearly orthogonal okay. 222 00:29:28,650 --> 00:29:40,050 Christodoulou Marios: There is, this is really just putting things together there's no real calculation that the reason we do this is because we want to show. 223 00:29:41,610 --> 00:29:52,050 Christodoulou Marios: That these phases that are creating the entanglement that people are talking about our own selections right, so you the final state is. 224 00:29:52,950 --> 00:30:08,850 Christodoulou Marios: The evolution of either active or the initial state and it's simple a few simple steps show you that the final state is going to be proportional we don't care about the normalization because we want the phases, to the final state of. 225 00:30:09,870 --> 00:30:10,980 Christodoulou Marios: This is the field. 226 00:30:12,360 --> 00:30:15,810 Christodoulou Marios: And the paths this side it's more site. 227 00:30:17,880 --> 00:30:25,500 Christodoulou Marios: And the speeds are factoring out in terms of product, but they have these phases, which, if they're not. 228 00:30:26,880 --> 00:30:36,450 Christodoulou Marios: which can give you a nonzero entanglement depending on what they are, where the phases are defined as these contracts. 229 00:30:37,650 --> 00:30:38,310 Christodoulou Marios: And this is. 230 00:30:39,390 --> 00:30:39,960 Christodoulou Marios: The point. 231 00:30:41,910 --> 00:30:45,660 Christodoulou Marios: That these phases let's create entanglement our own selections. 232 00:30:46,860 --> 00:30:47,520 Christodoulou Marios: Now. 233 00:30:49,230 --> 00:30:57,540 Christodoulou Marios: All right, what these men see particular than you, you can check it explicitly which we did is that it means they're going to be gauge of rem. 234 00:31:04,500 --> 00:31:04,740 Christodoulou Marios: and 235 00:31:05,280 --> 00:31:15,990 Abhay Vasant Ashtekar: What is a field i'm sorry, it is just an atonement field grab the i'm confused about what the framework is, are we talking about sheila as being produced by oh if you're just talking right now okay. 236 00:31:16,740 --> 00:31:19,140 Christodoulou Marios: Yes, yes i'm doing things to be done. 237 00:31:20,910 --> 00:31:21,090 Abhay Vasant Ashtekar: But. 238 00:31:22,440 --> 00:31:26,910 Abhay Vasant Ashtekar: paradigm is that there's a flag space and flash space time and then there is a perturbation on it. 239 00:31:27,480 --> 00:31:31,140 Abhay Vasant Ashtekar: Yes, produced only by this by these particles. 240 00:31:31,890 --> 00:31:33,270 Abhay Vasant Ashtekar: Yes, what is particles. 241 00:31:33,900 --> 00:31:36,870 Christodoulou Marios: Yes, yes, the setup is. 242 00:31:38,190 --> 00:31:39,630 Christodoulou Marios: Linares gravity first order. 243 00:31:41,070 --> 00:31:42,840 Christodoulou Marios: Where this is across the space. 244 00:31:45,630 --> 00:31:52,650 Christodoulou Marios: Of a domino, and this is a perturbation which will be sourced by the trajectory of the parks. 245 00:31:53,010 --> 00:31:54,750 Abhay Vasant Ashtekar: So you're ignoring earth's gravitational field. 246 00:31:55,860 --> 00:31:56,490 Christodoulou Marios: Excuse me. 247 00:31:56,700 --> 00:32:02,880 Abhay Vasant Ashtekar: But yet ignoring earth's gravitational field in which this part, yes, there is no external field it's all is that. 248 00:32:03,780 --> 00:32:06,120 Christodoulou Marios: There is also ignoring the back reaction. 249 00:32:07,350 --> 00:32:11,100 Christodoulou Marios: Yes, there is, there is an external magnetic field. 250 00:32:13,140 --> 00:32:27,030 Christodoulou Marios: Which is manipulating the spins but we're ignoring the back reaction of the spins end of the magnetic field on the field and where are so ignoring the reaction of the field of hulu on the trajectories of the park. 251 00:32:27,030 --> 00:32:28,200 Abhay Vasant Ashtekar: grows right. 252 00:32:28,980 --> 00:32:29,340 Yes. 253 00:32:31,350 --> 00:32:31,590 Abhay Vasant Ashtekar: Okay. 254 00:32:31,890 --> 00:32:37,830 Christodoulou Marios: The point being that this is enough to get the Lawrence engage in violent expression of the subjects. 255 00:32:39,900 --> 00:32:42,960 Abhay Vasant Ashtekar: don't control like and what i'm confused about is it, why is it. 256 00:32:45,060 --> 00:32:46,830 Abhay Vasant Ashtekar: Okay, please go maybe we should respond. 257 00:32:47,070 --> 00:32:48,120 Christodoulou Marios: No, no, please, please. 258 00:32:48,930 --> 00:32:49,860 Abhay Vasant Ashtekar: i'm confused about. 259 00:32:51,300 --> 00:32:59,760 Abhay Vasant Ashtekar: One can do things that are you know when can do calculations and it's a good motivation to do calculations, because we can finish the calculation and when was the last time that. 260 00:33:00,300 --> 00:33:10,170 Abhay Vasant Ashtekar: But I think affordable for us, for the rest of us, we want to know what is the justification of this approximation, why do we think that those effects are negligible. 261 00:33:11,520 --> 00:33:21,840 Abhay Vasant Ashtekar: And, and my thing is that in action lab if you are going to perform the experiment, then of course they'll be earth's gravitational field, but more than others, Guy will feel there'll be posted on the fence. 262 00:33:22,710 --> 00:33:36,810 Abhay Vasant Ashtekar: And the new new coming from the poster donnie and effect, why is that going to be negligible compared to you know the final answer that i'm getting these are the kinds of questions, I mean you can consider the ideal I systems, but. 263 00:33:38,220 --> 00:33:38,460 Christodoulou Marios: Yes. 264 00:33:40,410 --> 00:33:47,670 Christodoulou Marios: Yes, I think we're not doing them because we expect them, let them complete negligible by would be nice if I should but I agree okay. 265 00:33:48,180 --> 00:33:49,020 Christodoulou Marios: So, so the polling. 266 00:33:49,050 --> 00:33:54,390 Abhay Vasant Ashtekar: Looking at idealized system and just seeing what the calculation does and i'm perfectly happy with that. 267 00:33:56,550 --> 00:33:56,880 Christodoulou Marios: Yes. 268 00:33:59,160 --> 00:33:59,670 Christodoulou Marios: Yes. 269 00:33:59,880 --> 00:34:07,470 Ivan Agullo: I was confused with something you just said, you said that you are neglecting the map reaction of hulu on the directory of the particles. 270 00:34:08,040 --> 00:34:13,800 Ivan Agullo: In the end of us because it's not the game here that the two particles interact via HBO so the. 271 00:34:14,190 --> 00:34:20,760 Christodoulou Marios: Lead so that is a very good point I think that's a big part of how this debate can be resolved. 272 00:34:23,250 --> 00:34:35,700 Christodoulou Marios: Let me go to the next slide and then we can come back to this yes so just so that they can define things precise so here, this is the action of Linares gravity. 273 00:34:36,990 --> 00:34:39,840 Christodoulou Marios: The full action you get that the first order. 274 00:34:43,110 --> 00:34:49,440 Christodoulou Marios: If you expand to actually hit production, this is written lauren stage. 275 00:34:50,520 --> 00:34:56,160 Christodoulou Marios: The questions of motion that i'm sure you're all familiar, all are familiar with. 276 00:34:57,330 --> 00:35:14,520 Christodoulou Marios: And then you plug in the solution you use the questions of motion back into the action and you get this on selection, which is not surprisingly, this term, but there is a one over for this one house factor which is important to get them, then you turn a limit correct. 277 00:35:15,660 --> 00:35:16,980 Christodoulou Marios: Otherwise you get twice. 278 00:35:18,000 --> 00:35:18,390 Christodoulou Marios: The. 279 00:35:19,890 --> 00:35:23,490 Christodoulou Marios: neutrons gravity you get twice as big things. 280 00:35:26,850 --> 00:35:30,630 Christodoulou Marios: Now the team he knew their energy sensor is given by. 281 00:35:32,250 --> 00:35:33,810 Christodoulou Marios: a collection of point park to god's. 282 00:35:36,480 --> 00:35:38,490 Christodoulou Marios: You see, the deltas that they're forcing. 283 00:35:39,780 --> 00:35:43,560 Christodoulou Marios: The Court ministry on these paths. 284 00:35:46,320 --> 00:35:46,860 Christodoulou Marios: and 285 00:35:48,930 --> 00:35:53,280 Christodoulou Marios: We will know is simply it's the favelas this. 286 00:35:54,570 --> 00:35:55,830 Christodoulou Marios: And the Lawrence fact. 287 00:35:58,830 --> 00:36:05,940 Christodoulou Marios: Alright, so this is entertainment content sort of point particles or jacket and a source. 288 00:36:07,230 --> 00:36:12,990 Christodoulou Marios: Now you can see here what I meant that these acts of tr God given here. 289 00:36:14,010 --> 00:36:18,930 Christodoulou Marios: You just determined them from the beginning for all time and then you get the feet. 290 00:36:20,970 --> 00:36:26,280 Christodoulou Marios: For that now you have an exact fit solution for these two minutes. 291 00:36:27,330 --> 00:36:29,850 Christodoulou Marios: All right, this is the exact solution of the. 292 00:36:32,310 --> 00:36:34,980 Christodoulou Marios: Question so motion of the literacy of these questions. 293 00:36:36,390 --> 00:36:47,700 Christodoulou Marios: These are the Essentially, these are the analog the gravitational Allah log to the linear weaker solutions if you have heard of them of electromagnetism. 294 00:36:49,200 --> 00:36:54,210 Christodoulou Marios: which are very known they're also in advanced courses of electromagnetism. 295 00:36:55,230 --> 00:37:02,250 Christodoulou Marios: And it's the solutions that people use to cloth diaper radiation, for instance animations but they show us in class. 296 00:37:05,910 --> 00:37:20,220 Christodoulou Marios: Yes, again, this is an exact solution and the quantities in here this distances are impacted quantities they depend on the type of time which is implicitly defined by this condition here. 297 00:37:23,730 --> 00:37:36,300 Christodoulou Marios: And then the actual action you just plug this solution back to your action, and you can write a an exact expression within Linares gravity, I mean it's exactly it's exactly electromagnetism. 298 00:37:41,130 --> 00:37:47,580 Christodoulou Marios: Where again, the time is defined the Priestly the title tends to mean by this condition. 299 00:37:48,720 --> 00:37:56,340 Christodoulou Marios: What that does just to remind you is that, did you ask for the value of the field that some eggs empty. 300 00:37:57,870 --> 00:37:59,280 Christodoulou Marios: their entire time we. 301 00:38:00,360 --> 00:38:04,920 Christodoulou Marios: produced by some particle that is doing some trajectory then. 302 00:38:06,000 --> 00:38:16,200 Christodoulou Marios: It will trace the light con and find the detective time to be on that trajectory and that's where to click here so. 303 00:38:18,930 --> 00:38:31,980 Christodoulou Marios: This is the Lawrence advantage revised version for the observer balls we conclude that entanglement arises due to a local interaction mediated by physical degrees of freedom oops this type of here sorry. 304 00:38:33,120 --> 00:38:36,210 Christodoulou Marios: and not to come to your question event. 305 00:38:38,460 --> 00:38:46,320 Christodoulou Marios: There is i'm saying that this is more than sufficient is because when you see, this is a full thing this is lauren surviving scheduled right and it has. 306 00:38:46,710 --> 00:39:05,070 Christodoulou Marios: Corrections relativistic corrections have two kinds of the corrections to the mass and to the momentum so the sourcing of the field by momentum and by mass it, so this is what I mean by this is that this is not only T 00 it has all the energy. 307 00:39:06,270 --> 00:39:08,520 Christodoulou Marios: Momentum cancer components. 308 00:39:09,810 --> 00:39:11,820 Christodoulou Marios: In it, and then there's also a little dash. 309 00:39:12,930 --> 00:39:13,320 Christodoulou Marios: All right. 310 00:39:16,350 --> 00:39:27,780 Christodoulou Marios: Now you can go backwards and say Okay, how do I recover this formula which was this newtonian face think that we find in this papers. 311 00:39:28,830 --> 00:39:45,630 Christodoulou Marios: Well, first, you can take a slow moving approximation, which is simply that the velocities much less and see and you get I think it's plus O V C squared corrections, you can see in the paper we have it. 312 00:39:47,760 --> 00:39:57,000 Christodoulou Marios: And this is basically it looks like the causal version of newton's law when you're right, it is an action, this still has rehabilitation in it. 313 00:40:01,710 --> 00:40:03,630 Christodoulou Marios: All right, and then you can. 314 00:40:04,800 --> 00:40:20,520 Christodoulou Marios: also take an independent approximation, which we can call near field, which is when you neglect the Foundation effects in the vicinity of where you're taking where you're doing the experiment you just put them instantaneous the coordinate pain. 315 00:40:22,080 --> 00:40:32,310 Christodoulou Marios: When you take both approximations you get the than your turn and limit and you also assumes that this is this or this, because this is what they're doing this from some static phase here. 316 00:40:33,450 --> 00:40:40,080 Christodoulou Marios: That gives you the dominant contribution if you also do that, then you get back this formula so. 317 00:40:43,080 --> 00:40:54,960 Christodoulou Marios: To answer your question Yvonne it does not seem so does not seem that you need to consider the reaction of the field on the trajectory of the particles, because this is more than sufficient to give you. 318 00:40:56,670 --> 00:40:58,740 Christodoulou Marios: It obviously gives the correct limit. 319 00:41:00,360 --> 00:41:01,890 Christodoulou Marios: It already includes. 320 00:41:03,300 --> 00:41:07,530 Christodoulou Marios: sedation and other kinds of relativistic effects and. 321 00:41:08,940 --> 00:41:22,800 Christodoulou Marios: This is simply not what you would detect in the expert you, even if there is a correction, the particles it's the wrong petition to think about what you're detecting is that the particles go a bit closer because of the gravitational attraction. 322 00:41:24,120 --> 00:41:37,740 Christodoulou Marios: That is completely negligible sorry I didn't do don't have the calculation, but we have this in the previous paper with Carl it's easy to write down it's like terms of this magnitude below, so the Judas divination. 323 00:41:39,540 --> 00:41:48,780 Christodoulou Marios: And this is where the confusion comes from to that, if this is not for detecting then, how is our the gravitational degrees of freedom involved in the experiment. 324 00:41:53,460 --> 00:41:53,940 Abhay Vasant Ashtekar: You want. 325 00:41:54,210 --> 00:41:57,900 Christodoulou Marios: I just I just have the last slide maybe I just read through it. 326 00:41:58,650 --> 00:41:59,370 Ivan Agullo: Please, and we go. 327 00:42:00,390 --> 00:42:00,750 All right. 328 00:42:03,150 --> 00:42:18,030 Christodoulou Marios: Yes, I wanted to explain just one last thing that in this paper we also show that there is a way to make this observable right which is that what you do is that you shoot the particles. 329 00:42:19,110 --> 00:42:27,300 Christodoulou Marios: so fast through this so you do an undo this wasn't so fast that the light cons look like this. 330 00:42:28,920 --> 00:42:36,030 Christodoulou Marios: So what is the more precise way to say that the D E is less than city. 331 00:42:37,980 --> 00:42:38,340 Christodoulou Marios: way around. 332 00:42:41,520 --> 00:42:41,970 Christodoulou Marios: and 333 00:42:44,940 --> 00:42:50,040 Christodoulou Marios: Which means that they will they while they're in superposition. 334 00:42:51,120 --> 00:42:54,780 Christodoulou Marios: They have not yet interrupt the gravitational, which means that you will get zero and Panda. 335 00:42:56,430 --> 00:42:58,920 Christodoulou Marios: And then just simple derivation in the paper. 336 00:43:00,450 --> 00:43:08,220 Christodoulou Marios: So this gives you the observable effect them and for gravity has to be completed in physical, fortunately, but it could be done for electromagnetism. 337 00:43:08,910 --> 00:43:17,130 Christodoulou Marios: Which is still interesting because all these arguments and counter arguments they also apply to electromagnetism this will make the point that. 338 00:43:17,880 --> 00:43:28,170 Christodoulou Marios: Look, this is not instantaneous I think it takes some time to build that these phases take some time to build up because there is with edition here all right. 339 00:43:29,340 --> 00:43:31,050 Christodoulou Marios: And discussion. 340 00:43:33,690 --> 00:43:42,270 Christodoulou Marios: quickly go through the slide there have been claimed that the gravity disentangled minute similar experiments can provide fear, independent and big evidence. 341 00:43:42,900 --> 00:43:51,750 Christodoulou Marios: The gravitational field isn't with classical this heavily relies on electricity rents low calibrated operations in classical communication. 342 00:43:52,830 --> 00:44:03,600 Christodoulou Marios: Of quantum information which may be too strong statement I given two papers, where this is claimed personally were looking into this I didn't i'm not sure. 343 00:44:04,080 --> 00:44:11,670 Christodoulou Marios: I do not think you can make the theory independent statement, it seems to me that the importance of the experiments is. 344 00:44:12,270 --> 00:44:21,000 Christodoulou Marios: Clear, if you take linear as quantum gravity and you say that look if you're you're thinking, the following sense is there a feature of this theory. 345 00:44:21,450 --> 00:44:32,520 Christodoulou Marios: That is quantum and it's being witnessed by this experiment, for instance, take the form of an apple it's also predictable yeah that's kind of gravity does it see any quantum feature of the theory, no. 346 00:44:33,900 --> 00:44:40,950 Christodoulou Marios: How about this phenomenon, I think, yes, in the sense that, if you do not have some prepositions have some classical states in the state space. 347 00:44:41,970 --> 00:44:42,690 Christodoulou Marios: You would not. 348 00:44:45,540 --> 00:44:46,950 Christodoulou Marios: The effect would not take place. 349 00:44:48,690 --> 00:44:49,500 Christodoulou Marios: Would you know the lot. 350 00:44:49,590 --> 00:44:55,620 Christodoulou Marios: Though it just saying that distinguishes it from let's say some classical gravity or other theories that. 351 00:44:58,020 --> 00:45:00,510 Christodoulou Marios: treat the gravitational effect as class. 352 00:45:04,320 --> 00:45:16,350 Christodoulou Marios: There remains confusion, what exactly is going on with stuff from to fit this the papers I mentioned, this is, in particular with respect to the role of ideation the minimum of two degrees of freedom. 353 00:45:17,940 --> 00:45:25,380 Christodoulou Marios: an experiment, where all sorts of different is witness would be much more powerful because locality need not be assumed, but this is difficult. 354 00:45:26,550 --> 00:45:27,180 Christodoulou Marios: and 355 00:45:29,130 --> 00:45:43,860 Christodoulou Marios: I wanted to mention briefly this work, which, fortunately, they have to talk about this is a completely different protocol, which does not suffer from these issues, which is based on witnessing the negotiated the production on in quantum gases. 356 00:45:48,780 --> 00:45:58,350 Christodoulou Marios: it's completely open to think of alternative protocols techniques and smarter measurements to think of other tests, like this one, for instance. 357 00:45:59,370 --> 00:46:12,360 Christodoulou Marios: And yes, this is things I talked about in the last purchase, which is about the description of time, the excuse me, that its greatness of time I don't have much to report on this front So yes. 358 00:46:31,980 --> 00:46:32,280 carlos beltrán: slides. 359 00:46:34,170 --> 00:46:45,870 carlos beltrán: And because you said that the trajectories of the particles are all to go now but I don't know why I mean, I think the states are going i'm not a trajectory but maybe i'm wrong. 360 00:46:47,760 --> 00:46:50,070 Christodoulou Marios: I mean, if you think of them as wave pockets. 361 00:46:51,150 --> 00:46:55,560 Christodoulou Marios: Somehow is week functions website l say our. 362 00:46:56,640 --> 00:47:01,740 Christodoulou Marios: Side side are almost zero so they overlap of this girl oceans this. 363 00:47:03,210 --> 00:47:08,760 carlos beltrán: Statement server space not it's not exactly the trajectories of the park okay. 364 00:47:11,460 --> 00:47:11,790 Yes. 365 00:47:15,240 --> 00:47:22,920 Abhay Vasant Ashtekar: So let me just ask a couple of quizzes Well, first of all, you, and if you go to the previous slide at the previous slide maybe 16. 366 00:47:24,660 --> 00:47:31,530 Abhay Vasant Ashtekar: yeah So here we see that you are as of last formula area or down as a seat to the fourth there so on right. 367 00:47:32,820 --> 00:47:35,940 Abhay Vasant Ashtekar: So you would imagine that I am just confused about. 368 00:47:37,170 --> 00:47:46,770 Abhay Vasant Ashtekar: Sports at all if you can newtonian limit and such thing I would I just thought that, therefore, in the middle, in the middle just get zero answer but that's not the case. 369 00:47:48,510 --> 00:47:49,170 Christodoulou Marios: So. 370 00:47:53,010 --> 00:48:00,540 Christodoulou Marios: So this is a limit take this formula that is here at the now what you do is that you expand in powers of the receipt. 371 00:48:01,140 --> 00:48:05,940 Abhay Vasant Ashtekar: yeah, but I think you just get to but yeah Okay, but still, it is see the the. 372 00:48:05,970 --> 00:48:06,480 Abhay Vasant Ashtekar: morning that. 373 00:48:07,080 --> 00:48:11,010 Christodoulou Marios: knows you lose see from here with cancels out. 374 00:48:12,720 --> 00:48:14,100 Christodoulou Marios: This is, this is what you get. 375 00:48:15,450 --> 00:48:18,270 Abhay Vasant Ashtekar: I do this is C squared is my question exactly. 376 00:48:18,900 --> 00:48:20,400 Abhay Vasant Ashtekar: You see, to the fourth their. 377 00:48:22,650 --> 00:48:25,590 Christodoulou Marios: message to their paper because they just don't remember this behind. 378 00:48:26,790 --> 00:48:29,370 Christodoulou Marios: what's going on is this that. 379 00:48:32,430 --> 00:48:35,700 Christodoulou Marios: Sorry, by the pen is not working now just above a question 10. 380 00:48:37,200 --> 00:48:37,890 Christodoulou Marios: This. 381 00:48:39,000 --> 00:48:44,790 Christodoulou Marios: V times we term, which is in the Question nine is equal to see fourth. 382 00:48:44,910 --> 00:48:47,640 Abhay Vasant Ashtekar: is going to be C squared, so why do you see for. 383 00:48:50,580 --> 00:48:51,090 Christodoulou Marios: sure. 384 00:48:53,700 --> 00:48:56,490 Abhay Vasant Ashtekar: yeah my back and figure was I thought should be C squared Therefore I. 385 00:48:57,570 --> 00:49:00,090 Abhay Vasant Ashtekar: Thought okay i'll go back and look at it, thank you. 386 00:49:00,360 --> 00:49:07,440 Christodoulou Marios: Yes, in the supplementary material just to get you will have the derivation really step by step, starting from the action. 387 00:49:09,690 --> 00:49:12,000 Christodoulou Marios: doing everything but I don't remember, sir. 388 00:49:13,140 --> 00:49:13,680 Christodoulou Marios: Sir. 389 00:49:14,580 --> 00:49:16,560 Hal Haggard: In your appendix isn't it right there. 390 00:49:19,170 --> 00:49:24,840 Hal Haggard: That your definition of the capital, the new new it goes like B squared no. 391 00:49:26,130 --> 00:49:26,430 Hal Haggard: Yes. 392 00:49:26,460 --> 00:49:27,990 Christodoulou Marios: See here, yes it's from. 393 00:49:27,990 --> 00:49:28,410 Christodoulou Marios: here. 394 00:49:28,500 --> 00:49:29,220 Abhay Vasant Ashtekar: it's Friday. 395 00:49:29,250 --> 00:49:32,160 Abhay Vasant Ashtekar: Other right capital B is not the same as me. 396 00:49:33,480 --> 00:49:34,140 Christodoulou Marios: Yes, yes. 397 00:49:34,200 --> 00:49:37,470 Abhay Vasant Ashtekar: I saw the capital V was just okay. 398 00:49:38,130 --> 00:49:38,790 Christodoulou Marios: So tell me a. 399 00:49:39,930 --> 00:49:43,890 Hal Haggard: Little V squared and then he had capital D squared so that gives us yes. 400 00:49:44,520 --> 00:49:48,540 Abhay Vasant Ashtekar: That is fine, because capital I capital, it was around all cities. 401 00:49:50,670 --> 00:50:00,780 Christodoulou Marios: Yes, that's where it's yes it's a bad choice of notation so this capital V has to Vanessa it's the stuck here, so my question is TIM yes. 402 00:50:01,890 --> 00:50:05,250 Abhay Vasant Ashtekar: Okay, so, then my second question is, why is it. 403 00:50:06,270 --> 00:50:17,430 Abhay Vasant Ashtekar: I mean if in fact they already controversy in electromagnetism where you think the shoes are clear cut because no, you know don't have to worry about superposition of space time or anything or anything. 404 00:50:19,170 --> 00:50:22,530 Abhay Vasant Ashtekar: Can you tell us why there is controversy in the electromagnetism where you know. 405 00:50:23,910 --> 00:50:24,360 Abhay Vasant Ashtekar: relationship. 406 00:50:26,460 --> 00:50:27,120 Christodoulou Marios: Because. 407 00:50:31,020 --> 00:50:32,370 Christodoulou Marios: Essentially, people are saying. 408 00:50:33,870 --> 00:50:37,770 Christodoulou Marios: There is confusion about the immediate or what is going on with immediate. 409 00:50:38,730 --> 00:50:52,260 Christodoulou Marios: What you can say is that look, this is a Colombian tax, we know that did you take a quantum mechanics your room you put the one over our interaction and the hamiltonian as you're going to get entangled, why are you making all this fuss about having sense, so if you're thinking. 410 00:50:53,280 --> 00:50:59,160 Christodoulou Marios: you're thinking about the electromagnet this would be my language, the position of. 411 00:51:00,330 --> 00:51:04,560 Christodoulou Marios: semi classical configurations of the feet of the electromagnetic field. 412 00:51:05,940 --> 00:51:06,600 Christodoulou Marios: However. 413 00:51:09,960 --> 00:51:14,850 Christodoulou Marios: It is not true right that this instantaneous interaction is just an approximation. 414 00:51:15,900 --> 00:51:19,080 Christodoulou Marios: Now, if what is really going on is. 415 00:51:20,430 --> 00:51:23,130 Christodoulou Marios: But there is a local interaction that is mediating. 416 00:51:25,020 --> 00:51:38,310 Christodoulou Marios: So the introduction is mediated locally by some, something that is in the middle there's a third system, you know just the masses and they miss the time is traction there is a third system that corresponds to that direction, then. 417 00:51:39,750 --> 00:51:49,020 Christodoulou Marios: That media or that gravitational link that fame I was talking about, so that bus, if you want it needs to be able to query quantum information. 418 00:51:50,160 --> 00:51:56,130 Christodoulou Marios: And that cannot happen if it's a classical that's where all the story starts from. 419 00:51:57,900 --> 00:52:05,160 Christodoulou Marios: I say said this type of argument or investigating it i'm not sure how much water it holds. 420 00:52:06,660 --> 00:52:15,030 Christodoulou Marios: To this moment, but I think there is something interesting there to understand, so that the confusion is basically that this seems to have nothing to do the radiation. 421 00:52:16,170 --> 00:52:21,390 Christodoulou Marios: Yes, it has seems to have to do with the red non relative part but. 422 00:52:22,770 --> 00:52:26,430 Christodoulou Marios: If you do the usual thing of splitting. 423 00:52:28,950 --> 00:52:41,070 Christodoulou Marios: Taking out the transfers parts electromagnetism or the transfers tasteless that you're putting all the degrees of freedom in there, but then you're going to neglect them, because this is what you would do you understand the radiation in the far field. 424 00:52:42,660 --> 00:52:48,660 Christodoulou Marios: So this step seems to not be appropriate to explain the how the information is mediated. 425 00:52:51,660 --> 00:52:55,020 Christodoulou Marios: Yes, and what is the correct way to say things I don't know. 426 00:52:59,010 --> 00:53:00,270 Abhay Vasant Ashtekar: Okay, thank you, I mean I. 427 00:53:02,430 --> 00:53:03,330 Christodoulou Marios: know no please. 428 00:53:05,010 --> 00:53:11,250 Abhay Vasant Ashtekar: I know I mean, I think that it might much easier to is much easier to look at electromagnetism and then. 429 00:53:12,600 --> 00:53:23,130 Abhay Vasant Ashtekar: I mean it just would have been correct and and to see to what extent it is true that in quantum electrodynamics the color of interaction, he is really. 430 00:53:24,270 --> 00:53:25,350 Abhay Vasant Ashtekar: classic right. 431 00:53:26,400 --> 00:53:29,730 Abhay Vasant Ashtekar: And I think that it is not cool of interaction is as customers. 432 00:53:31,890 --> 00:53:32,190 Christodoulou Marios: Okay. 433 00:53:32,910 --> 00:53:34,500 Christodoulou Marios: That is very inconvenient book here from. 434 00:53:35,880 --> 00:53:39,570 Christodoulou Marios: All these papers do treat the electronic design also. 435 00:53:41,610 --> 00:53:49,050 Abhay Vasant Ashtekar: You mentioned that I was going to fill up that there are a lot of controversies they're also used to it okay and i'm happy to understand what the. 436 00:53:50,310 --> 00:53:53,070 Abhay Vasant Ashtekar: What the debate is a lot. 437 00:53:55,500 --> 00:54:03,840 Christodoulou Marios: That it would take another seminar maybe I mean i'm bad at explaining this I would encourage you to have a look at the book volts paper, the latest one yeah. 438 00:54:05,340 --> 00:54:13,020 Christodoulou Marios: So we haven't really put the two things together they're saying what we're saying is related to this stuff we're saying it must be related, but I think. 439 00:54:14,040 --> 00:54:20,040 Christodoulou Marios: Nobody has figured it out we're in discussions, yes, I expect that to continue. 440 00:54:21,420 --> 00:54:21,750 Abhay Vasant Ashtekar: Thank you. 441 00:54:22,230 --> 00:54:39,930 Ivan Agullo: But what one question related to this, I mean the two particles are nearby So how do you separate the radiative and they go on the part of of any field if it's you know my understanding is that there is some DVD unless you go to the to the radio, the freedom right really far away so. 442 00:54:39,990 --> 00:54:47,100 Christodoulou Marios: that's what I think true and instead of trying to make sense of that which is what some people did, and you get this. 443 00:54:47,610 --> 00:55:02,250 Christodoulou Marios: other places, this is nothing to do with there's no degrees of freedom artificial graphs to do both things I just tried to do it in the current language, where you do not you do the path into crab you never have to split. 444 00:55:03,150 --> 00:55:04,410 Abhay Vasant Ashtekar: And here is the four layers. 445 00:55:04,470 --> 00:55:06,420 Abhay Vasant Ashtekar: That you cannot do the parking ticket splitting. 446 00:55:07,470 --> 00:55:09,720 Christodoulou Marios: Because, yes, you split the minor. 447 00:55:10,590 --> 00:55:13,680 Abhay Vasant Ashtekar: part would not be the major would not be gulshan. 448 00:55:15,300 --> 00:55:22,860 Abhay Vasant Ashtekar: Your district I don't think that part integral did anything beyond what will be done just an ordinary field theory, I mean. 449 00:55:24,810 --> 00:55:31,320 Abhay Vasant Ashtekar: This HBO new etc right, I mean they would not be the major on the space of. 450 00:55:32,790 --> 00:55:42,720 Abhay Vasant Ashtekar: If you include all degrees of freedom, I mean all 10 components H menu, and not just transfer stress less than the interior doesn't convert, as we know, right, I mean. 451 00:55:43,740 --> 00:55:50,040 Abhay Vasant Ashtekar: apart because of the, for example, because the confirm one degree of freedom in age from. 452 00:55:51,270 --> 00:56:02,700 Abhay Vasant Ashtekar: So I think that implicitly in this form of manipulation, there is actually splitting and you're probably are using transfers degrees of freedom without are the major corresponding transfers degrees of freedom. 453 00:56:04,230 --> 00:56:07,860 Christodoulou Marios: And I haven't defined the measure So yes, I agree with it it's completely hurry. 454 00:56:08,040 --> 00:56:15,690 Abhay Vasant Ashtekar: Without saying it right, exactly, so I don't think I think these are normal manipulations right, so it might be a case. 455 00:56:16,770 --> 00:56:26,640 Christodoulou Marios: Yes, yeah I wanted, I wanted to see what I meant to say is that they want to be covariance formula of the phases, but i've not for what could be hidden is you if you. 456 00:56:28,050 --> 00:56:31,890 Christodoulou Marios: Sit down and define them the path of the crowd precisely. 457 00:56:34,860 --> 00:56:38,880 Christodoulou Marios: Yes, I don't have anything on that, but thank you for the comment. 458 00:56:42,150 --> 00:56:42,900 Deepak Vaid: i'm RDS. 459 00:56:45,450 --> 00:56:45,690 Christodoulou Marios: hi. 460 00:56:46,620 --> 00:57:04,380 Deepak Vaid: So I have a, I guess, more than one question the first is like, as has already been mentioned by you and by be electromagnetic case would be the natural stepping stone to the gravitational case right because. 461 00:57:05,430 --> 00:57:16,170 Deepak Vaid: As one might, as we know from looking at these calculations, you get the same result only with G and being replaced by K and you. 462 00:57:17,250 --> 00:57:17,520 Christodoulou Marios: know. 463 00:57:17,580 --> 00:57:18,930 Deepak Vaid: So so. 464 00:57:20,100 --> 00:57:26,670 Deepak Vaid: Are there any plans for performing experiments, such as such experiments with with charged particles. 465 00:57:27,330 --> 00:57:37,440 Christodoulou Marios: Yes, there are they have their own difficulties there which are different from gravity, they have not happened, I have not had a detailed discussion so for why. 466 00:57:39,210 --> 00:57:46,050 Christodoulou Marios: One thing I can tell you is that, on this idea of putting them apart and back together a reversible. 467 00:57:46,080 --> 00:57:47,400 Christodoulou Marios: still get like was. 468 00:57:47,460 --> 00:57:48,840 Christodoulou Marios: reported like a year ago. 469 00:57:50,640 --> 00:57:54,630 Christodoulou Marios: So now, they would have to put to and measured interaction for electrons mean. 470 00:57:56,610 --> 00:58:09,150 Christodoulou Marios: Or what you said is completed through it said here, and as you can see that cannot show where it says, replacing V with small V on with you, and you can the formula for electromagnetism. 471 00:58:09,510 --> 00:58:10,110 Christodoulou Marios: it's completely and. 472 00:58:11,040 --> 00:58:14,160 Christodoulou Marios: I don't know why they haven't done it yet apparently sorts of. 473 00:58:15,060 --> 00:58:15,450 huh. 474 00:58:16,560 --> 00:58:20,460 Deepak Vaid: Okay, and this second thing is that um so if. 475 00:58:21,600 --> 00:58:25,350 Deepak Vaid: There are, there are two aspects right the first aspect is. 476 00:58:28,170 --> 00:58:30,570 Deepak Vaid: Can you generate entanglement. 477 00:58:31,620 --> 00:58:42,720 Deepak Vaid: Between any two systems which are interacting via some sort of one by R squared or some central potential right that's, the first thing and like like you said you, you can do that right in electromagnetism. 478 00:58:44,220 --> 00:58:46,320 Deepak Vaid: Yes, this The second thing is that. 479 00:58:49,080 --> 00:58:53,580 Deepak Vaid: If if one can do that with gravity Does that imply gravity is a. 480 00:58:54,660 --> 00:58:57,900 Deepak Vaid: You know quantum mechanical entity or if. 481 00:58:59,130 --> 00:58:59,940 Christodoulou Marios: That is a claim. 482 00:59:00,390 --> 00:59:03,810 Christodoulou Marios: That is a claim the dysphoria forces you to say that this. 483 00:59:04,830 --> 00:59:06,180 Christodoulou Marios: It cannot be a classical food. 484 00:59:06,810 --> 00:59:07,170 Right. 485 00:59:08,370 --> 00:59:14,010 Deepak Vaid: Now, the thing is that let's say that both of these are our our crew. 486 00:59:15,330 --> 00:59:15,780 Deepak Vaid: Then. 487 00:59:16,860 --> 00:59:24,330 Deepak Vaid: wouldn't the gravitational field be creating entanglement all over the place, you know, for instance, if I if I think about something. 488 00:59:25,560 --> 00:59:28,470 Deepak Vaid: hydrogen energy particles hitting the upper right. 489 00:59:29,520 --> 00:59:33,510 Deepak Vaid: you're drinking shoppers of new ones, or whatever other other kinds of back. 490 00:59:35,010 --> 00:59:40,860 Christodoulou Marios: Then, because there's nothing is going to be in principle in a superposition Everywhere you. 491 00:59:43,860 --> 00:59:47,700 Deepak Vaid: Go because you know I mean you have particles traveling around along different paths. 492 00:59:49,350 --> 00:59:53,070 Deepak Vaid: And i'm not saying of course that those configurations will. 493 00:59:56,250 --> 01:00:05,790 Christodoulou Marios: So I think what you're saying might be answered, so these three papers I mentioned from Bob lower voltage all three of them. 494 01:00:10,080 --> 01:00:16,740 Christodoulou Marios: They study quantum fluctuations and the thing is that you cannot get which path information, unless you can distinguish. 495 01:00:18,600 --> 01:00:28,410 Christodoulou Marios: So unless whatever is your prob can can be the localized sufficiently to distinguish it from vacuum fluctuations, otherwise you cannot get information, so you do not. 496 01:00:29,340 --> 01:00:37,650 Christodoulou Marios: generate entanglement and you'd also get the coherence and this is exactly the type of good I can experiment that has been that have been considered. 497 01:00:39,810 --> 01:00:42,900 Christodoulou Marios: In these papers here I lost my pencil here. 498 01:00:43,950 --> 01:00:46,650 Christodoulou Marios: In this three and this one. 499 01:00:49,380 --> 01:00:54,510 Christodoulou Marios: So it's you know you can just imagine that it's the whole thing classical everywhere, I mean there is. 500 01:00:56,130 --> 01:01:00,930 Christodoulou Marios: soon going to be a limit would get so small, the difference that you cannot religion or the impact. 501 01:01:02,370 --> 01:01:09,540 Christodoulou Marios: And that is something missing from the story is it, by the way, which we're trying to put that into the story to. 502 01:01:10,620 --> 01:01:13,470 Christodoulou Marios: Even sorry the packet if you were. 503 01:01:14,700 --> 01:01:18,150 Deepak Vaid: No, no, no, no, thanks I lost after afterwards. 504 01:01:18,810 --> 01:01:19,230 Christodoulou Marios: Thank you. 505 01:01:21,990 --> 01:01:22,470 Ivan Agullo: So. 506 01:01:24,480 --> 01:01:34,590 Ivan Agullo: What are you having just a conclusion about the main the main point so maybe you can help me to to to understand and so perhaps you can come back to your picture of the light cons. 507 01:01:39,660 --> 01:01:39,930 Ivan Agullo: Right. 508 01:01:40,950 --> 01:01:50,010 Ivan Agullo: So I understood from the beginning that the game, we are playing here is that these two particles are going to interact very. 509 01:01:50,490 --> 01:01:58,800 Ivan Agullo: are very interact gravitationally you know one is going to produce if they are going to interact by the mutual going to be the wrong direction. 510 01:01:59,610 --> 01:02:09,000 Ivan Agullo: And that is going to introduce faces that you can detect later on, but looking at the picture, so there are two things that confused me. 511 01:02:09,660 --> 01:02:22,980 Ivan Agullo: One is that in your calculation particle a never feels the gravitational field of article beat so so, then I don't understand how the whole picture can be realised can can be materialized. 512 01:02:23,850 --> 01:02:31,680 Ivan Agullo: And second this picture tells you that you know, whenever the two one particle be you know, like to party sessions are separated. 513 01:02:31,920 --> 01:02:48,990 Ivan Agullo: You know that is not in Council contact with particle a so so the gravitational interaction doesn't have enough time to reach each other so, then I don't understand a whole, you can have gravitationally in the face. 514 01:02:50,520 --> 01:03:00,480 Christodoulou Marios: Okay, so there was it's it's two parts, the second was my fault, so I was saying that, in this case when the lead concert like that you do not. 515 01:03:02,460 --> 01:03:06,150 Ivan Agullo: Do not get so you need you need, then, you know when to move forward in dental dealer. 516 01:03:06,810 --> 01:03:10,620 Christodoulou Marios: You need them to move slow enough so that the light console you know, like this. 517 01:03:13,260 --> 01:03:14,550 Christodoulou Marios: so that they can actually. 518 01:03:16,380 --> 01:03:16,530 Be. 519 01:03:18,960 --> 01:03:22,710 Christodoulou Marios: You need the trajectories to be in cause of contact. 520 01:03:24,930 --> 01:03:26,790 Christodoulou Marios: To unit this trajectory is to be. 521 01:03:29,310 --> 01:03:30,480 Christodoulou Marios: In the future of. 522 01:03:32,220 --> 01:03:33,810 Christodoulou Marios: At least most of them so. 523 01:03:35,100 --> 01:03:37,110 Christodoulou Marios: Is this clear what I said or am I think. 524 01:03:37,560 --> 01:03:38,580 Ivan Agullo: That that is perfectly. 525 01:03:39,240 --> 01:03:55,920 Christodoulou Marios: All right, good So the first part, I agree that this is this is counterintuitive and it's important so you're saying that do not fit the revelation of each other, because there is no just deviation but it's not, this is not only that. 526 01:03:56,160 --> 01:04:02,760 Ivan Agullo: Is because you are what you call the back reaction back reaction, you were you were saying that you know particle beam doesn't. 527 01:04:03,330 --> 01:04:04,080 Ivan Agullo: that's me yes. 528 01:04:04,140 --> 01:04:05,670 Ivan Agullo: react to the gravitational field. 529 01:04:05,760 --> 01:04:21,180 Christodoulou Marios: Created yes, yes, in this sense that we're not feeling the composition of the thought were putting quantum mechanics right and then quantum mechanics there it's also the phases and that's what we care about, and this is. 530 01:04:22,290 --> 01:04:28,800 Christodoulou Marios: What we show we just do the innovation, starting from the gravity and which we see that. 531 01:04:31,440 --> 01:04:35,670 Christodoulou Marios: Discussion quantum physicists are given in this theory by this expression. 532 01:04:38,550 --> 01:04:39,000 Christodoulou Marios: Right. 533 01:04:39,690 --> 01:04:49,050 Ivan Agullo: Maybe make my point is, why should I integrate that face as the reaction of particle be to the gravitational field of article. 534 01:04:49,290 --> 01:04:52,290 Christodoulou Marios: Because it's a function of of. 535 01:04:54,420 --> 01:04:55,140 Christodoulou Marios: This is. 536 01:04:56,280 --> 01:04:57,450 Christodoulou Marios: given us. 537 01:04:58,530 --> 01:04:59,070 Christodoulou Marios: This. 538 01:05:01,740 --> 01:05:08,850 Christodoulou Marios: that's what I would say that, because these phases are equal to this monster election, which is a function of vision. 539 01:05:09,900 --> 01:05:10,230 Christodoulou Marios: and 540 01:05:15,990 --> 01:05:17,730 Christodoulou Marios: I see you're just sitting there is something. 541 01:05:24,360 --> 01:05:25,620 Ivan Agullo: I mean, I just want to understand. 542 01:05:25,830 --> 01:05:28,050 Christodoulou Marios: It is it is due to the. 543 01:05:28,680 --> 01:05:33,120 Christodoulou Marios: I mean listen to this if it's not just the aggravation of what What did you. 544 01:05:38,160 --> 01:05:38,580 Thank you. 545 01:05:39,900 --> 01:05:41,130 Christodoulou Marios: Maybe that's. 546 01:05:41,160 --> 01:05:41,550 Jorge Pullin: Yes. 547 01:05:41,580 --> 01:05:42,690 But I agree that this. 548 01:05:46,620 --> 01:05:51,090 Christodoulou Marios: I don't know I don't have the sufficient to say there's no greater Chris waters. 549 01:05:52,380 --> 01:05:53,100 Christodoulou Marios: were thinking about. 550 01:05:58,410 --> 01:06:00,240 Suddhasattwa Brahma: So maybe you said this already. 551 01:06:00,990 --> 01:06:06,000 Suddhasattwa Brahma: But just to clarify, so the H menu for you is not just the transfers trace this more right it's like. 552 01:06:06,420 --> 01:06:07,950 Christodoulou Marios: No, this is this is. 553 01:06:08,430 --> 01:06:09,240 Christodoulou Marios: All of us, yes. 554 01:06:09,570 --> 01:06:17,190 Suddhasattwa Brahma: yeah Okay, and then my second question is, what do you call this until action it is essentially just like integrating all. 555 01:06:18,240 --> 01:06:20,370 Suddhasattwa Brahma: This new field right. 556 01:06:23,310 --> 01:06:23,550 Suddhasattwa Brahma: that's. 557 01:06:24,060 --> 01:06:24,900 Christodoulou Marios: More than just. 558 01:06:24,990 --> 01:06:27,570 Suddhasattwa Brahma: Integrating out to to the leading order. 559 01:06:30,330 --> 01:06:31,440 Christodoulou Marios: i'm. 560 01:06:32,820 --> 01:06:35,370 Christodoulou Marios: doing in the previous presenter provider was saying. 561 01:06:36,030 --> 01:06:36,780 Christodoulou Marios: Yes, yeah. 562 01:06:37,410 --> 01:06:38,970 Suddhasattwa Brahma: Because you're using the equation solution. 563 01:06:39,360 --> 01:06:41,220 Suddhasattwa Brahma: For it and then playing it back in radio. 564 01:06:41,400 --> 01:06:42,570 Christodoulou Marios: Yes, yes, yes. 565 01:06:43,230 --> 01:06:53,190 Suddhasattwa Brahma: So then, my question is, I mean if I just think of a to field to scale, a field system or something like this when we integrate out, we say we are integrating all the heavy fields, based on. 566 01:06:54,060 --> 01:07:05,760 Suddhasattwa Brahma: Energy scale which are which we consider right and we say, for me, the scale of what we are interested in is much smaller than the mass of the heavy field, or some some hierarchy like this, then we are allowed to integrate so. 567 01:07:06,030 --> 01:07:06,480 Am I. 568 01:07:07,590 --> 01:07:18,240 Suddhasattwa Brahma: Is there something like that is there some hierarchy of skills which you are implicitly considering him for which you can for which you can think of integrating out this a communion. 569 01:07:19,620 --> 01:07:19,950 Christodoulou Marios: Oh. 570 01:07:21,000 --> 01:07:26,670 Christodoulou Marios: that's a good point then another word that this has been that said in this way. 571 01:07:27,690 --> 01:07:42,390 Christodoulou Marios: In the papers that are there i'm suspecting that this is sort of what's going on, if you take this point of view of understanding, whether you can teach which part information or not with a scale being said by the vacuum fluctuation, but I have not. 572 01:07:44,820 --> 01:07:45,660 Suddhasattwa Brahma: Okay, all right. 573 01:07:46,260 --> 01:07:46,590 Christodoulou Marios: that's. 574 01:07:46,890 --> 01:07:47,970 Suddhasattwa Brahma: A good point so nice to. 575 01:07:58,740 --> 01:08:06,780 Deepak Vaid: Okay, I have one more question good so we're talking about particles, which is nice. 576 01:08:08,460 --> 01:08:09,660 Deepak Vaid: Now, and. 577 01:08:11,250 --> 01:08:14,610 Deepak Vaid: The gravity that you're using here right, I presume, is. 578 01:08:15,660 --> 01:08:18,990 Deepak Vaid: you're assuming make the torsion precondition and so on, right. 579 01:08:21,780 --> 01:08:23,280 Christodoulou Marios: yeah yes okay. 580 01:08:23,310 --> 01:08:24,540 Deepak Vaid: So so. 581 01:08:26,010 --> 01:08:27,750 Deepak Vaid: what one might. 582 01:08:29,340 --> 01:08:36,030 Deepak Vaid: expect or one might think that since you're dealing with the with particles which have spin. 583 01:08:36,570 --> 01:08:40,680 Deepak Vaid: night and Sprint courses spin sources portion in the Baptist and it. 584 01:08:43,710 --> 01:08:45,990 Deepak Vaid: shouldn shouldn't that play a role in these concerts. 585 01:08:47,730 --> 01:08:52,530 Christodoulou Marios: I have not thought of making that seeing whether it's. 586 01:08:55,230 --> 01:09:01,680 Christodoulou Marios: Yes, the answer is yes, it should resource section I agree with you i've not thought about that i've not looked at it. 587 01:09:05,220 --> 01:09:07,440 Christodoulou Marios: We just make a comment that this. 588 01:09:08,940 --> 01:09:14,280 Christodoulou Marios: spin degrees of freedom, I really there to use to be used as handled to move the particles around right. 589 01:09:15,330 --> 01:09:15,690 Christodoulou Marios: and 590 01:09:17,610 --> 01:09:21,420 Christodoulou Marios: Excuse me and they're also used to make measurements on them. 591 01:09:22,800 --> 01:09:25,590 Christodoulou Marios: to witness the entanglement but they're not. 592 01:09:26,730 --> 01:09:43,950 Christodoulou Marios: Really part of their you know of the interaction now i've no idea how to get to that effect that was imagine it's minuscule, but it would be tested on the other direction, three, given that they can do this thing in bed spins is an experiment to see. 593 01:09:47,550 --> 01:09:48,570 Christodoulou Marios: Whether or not i'm not. 594 01:09:52,500 --> 01:09:54,960 iPhone von Wolfgang Martin Wieland: So sorry to jump in. 595 01:09:56,100 --> 01:10:02,100 iPhone von Wolfgang Martin Wieland: On this point, so the the spin marvel use that you're talking about isn't it like this pin of. 596 01:10:03,180 --> 01:10:22,110 iPhone von Wolfgang Martin Wieland: microscopic amazes copy quantum system like a sea of glass or something that is just rotating and this kind of spin does not this like all with angular momentum this angular momentum is not like a spin that would cover to. 597 01:10:23,400 --> 01:10:32,700 iPhone von Wolfgang Martin Wieland: The other thing degrees of freedom of Lol electron or elementary particle, so this is a subtle. 598 01:10:34,530 --> 01:10:35,820 iPhone von Wolfgang Martin Wieland: distinction between the. 599 01:10:37,110 --> 01:10:38,550 iPhone von Wolfgang Martin Wieland: angular momentum of an. 600 01:10:39,930 --> 01:10:52,620 iPhone von Wolfgang Martin Wieland: spinning top or miss was copied quantum system and the fundamental spin that appears in elementary fields that and only those are sourcing torsion so that. 601 01:10:54,510 --> 01:10:55,560 iPhone von Wolfgang Martin Wieland: So I don't think that. 602 01:10:57,330 --> 01:10:58,170 Christodoulou Marios: which was awesome. 603 01:10:59,430 --> 01:10:59,700 iPhone von Wolfgang Martin Wieland: yeah. 604 01:10:59,730 --> 01:11:06,180 iPhone von Wolfgang Martin Wieland: So I don't think that torsion degrees of freedom will play any role in this kind of experiments as far as I. 605 01:11:06,690 --> 01:11:11,640 Christodoulou Marios: can see this in it's not there's nothing rotating just I don't know. 606 01:11:11,700 --> 01:11:15,180 Christodoulou Marios: How it would come back just to make clear that there's nothing growth, and this is really a. 607 01:11:15,600 --> 01:11:16,470 Christodoulou Marios: Fundamental spin. 608 01:11:16,950 --> 01:11:20,520 Deepak Vaid: These are electrons in degrees, or whatever right, I mean yeah. 609 01:11:23,250 --> 01:11:23,820 Deepak Vaid: I know. 610 01:11:25,410 --> 01:11:32,610 Christodoulou Marios: we're actually discussing this with you will can write about the torsion but I cannot tell you anything wrong, I really have not thought about this. 611 01:11:34,980 --> 01:11:37,920 Christodoulou Marios: sounds interesting but I don't think you might be useful. 612 01:11:39,510 --> 01:11:42,270 Christodoulou Marios: I have no way in my mind to estimate what. 613 01:11:42,270 --> 01:11:45,330 Christodoulou Marios: kind of order of magnitude effect were talking about. 614 01:11:50,100 --> 01:11:56,160 Deepak Vaid: And I mean if I were just just asked us Wolfgang I mean it's not directly related to the. 615 01:11:57,300 --> 01:12:07,170 Deepak Vaid: To the subject here, but we can send it to me any macro distribution with spin would source torsion I thought that is indeed the case. 616 01:12:10,950 --> 01:12:21,030 iPhone von Wolfgang Martin Wieland: Sure, but if, well, it depends on the actual where we are now talking not really about the content of this talk, but. 617 01:12:21,240 --> 01:12:22,410 iPhone von Wolfgang Martin Wieland: You know, it depends up. 618 01:12:23,610 --> 01:12:25,350 iPhone von Wolfgang Martin Wieland: Two points, one is. 619 01:12:26,610 --> 01:12:34,350 iPhone von Wolfgang Martin Wieland: It depends on which coupling you use between the if you're working a first order for relational section, the order of formulation. 620 01:12:35,550 --> 01:12:49,290 iPhone von Wolfgang Martin Wieland: of your your gravitational degrees of freedom and the that the coupling between gravity and spinning degrees of freedom is different, but the coupling of. 621 01:12:50,220 --> 01:13:01,830 iPhone von Wolfgang Martin Wieland: offer of an object it just rotates like they're the moon order moves in the gravitational field, these would never be the source of this would not, this is not this also. 622 01:13:03,000 --> 01:13:07,650 iPhone von Wolfgang Martin Wieland: This is not the kind of angular momentum that sources torsion only. 623 01:13:09,690 --> 01:13:11,070 iPhone von Wolfgang Martin Wieland: Only intrinsic scheme. 624 01:13:12,360 --> 01:13:15,900 iPhone von Wolfgang Martin Wieland: But in any case only intrinsic spin off permissions. 625 01:13:17,460 --> 01:13:19,860 iPhone von Wolfgang Martin Wieland: can be as a source of torsion. 626 01:13:21,360 --> 01:13:34,500 Deepak Vaid: that's that's if you can only coupling why the connection right, but if you if you if you consider the stress energy Center induced by any spinning object right you get a contribution from the. 627 01:13:35,880 --> 01:13:42,240 Deepak Vaid: From that from that from the rotation of that object, whether its intrinsic or extrinsic it doesn't matter. 628 01:13:44,130 --> 01:13:47,460 iPhone von Wolfgang Martin Wieland: What is this is, this is a, this is no. 629 01:13:47,790 --> 01:13:48,450 iPhone von Wolfgang Martin Wieland: I mean the. 630 01:13:50,460 --> 01:13:57,990 iPhone von Wolfgang Martin Wieland: The the the emotional spinning top, for instance in the gravitational field is determined by the by the. 631 01:14:00,840 --> 01:14:17,010 iPhone von Wolfgang Martin Wieland: Top of better equations and they don't are defined for one day I equations for so a connection interstellar that tells you how to spin moves in a gravitational field, but these these these equations for social portion list so that there is. 632 01:14:18,480 --> 01:14:26,490 iPhone von Wolfgang Martin Wieland: These are just we're just getting confused by this discussion on i'm afraid but, and it has nothing to do with the. 633 01:14:28,380 --> 01:14:30,840 iPhone von Wolfgang Martin Wieland: content of my sister you. 634 01:14:32,250 --> 01:14:33,480 iPhone von Wolfgang Martin Wieland: know where to say, I will take. 635 01:14:34,020 --> 01:14:35,160 Christodoulou Marios: Yes, no, thank you for. 636 01:14:37,050 --> 01:14:37,650 Christodoulou Marios: The comments. 637 01:14:37,770 --> 01:14:39,810 iPhone von Wolfgang Martin Wieland: At water I know if I just. 638 01:14:43,980 --> 01:14:49,650 iPhone von Wolfgang Martin Wieland: mentioned something with Yvonne what is kind of missing here is. 639 01:14:50,760 --> 01:14:54,750 iPhone von Wolfgang Martin Wieland: To explain how how it is possible that. 640 01:14:56,490 --> 01:15:08,790 iPhone von Wolfgang Martin Wieland: to neglect back reaction for, for instance at the mathematical every year he knew his satisfies engaged condition, so that they knew that that it's. 641 01:15:09,630 --> 01:15:30,120 iPhone von Wolfgang Martin Wieland: The version less and and also their energy momentum and so then has to satisfy this condition, but this then implies, in turn, that the that your trajectories would move along geodesics, at least in this approximation, so there is a interplay between the. 642 01:15:32,010 --> 01:15:38,100 iPhone von Wolfgang Martin Wieland: covariance divergence of the energy momentum tensor the particles moving. 643 01:15:39,120 --> 01:15:50,460 iPhone von Wolfgang Martin Wieland: Around along geodesics and the gauge conditions to be chosen to be imposed on he knew and all these conditions need to be consistent. 644 01:15:51,510 --> 01:15:51,960 iPhone von Wolfgang Martin Wieland: and 645 01:15:53,670 --> 01:15:54,120 iPhone von Wolfgang Martin Wieland: and 646 01:15:57,270 --> 01:15:59,790 Christodoulou Marios: Here, do you think that first doctor that wouldn't be. 647 01:16:01,590 --> 01:16:09,690 Christodoulou Marios: done, I mean wouldn't be there to this vision, I didn't know I haven't checked and they see what you're saying yes. 648 01:16:11,010 --> 01:16:11,670 Christodoulou Marios: I would be. 649 01:16:12,720 --> 01:16:25,590 iPhone von Wolfgang Martin Wieland: So I will what I think is one only what is missing is to to understand where the external forces are showing up in this in this in this argument and then. 650 01:16:26,850 --> 01:16:39,600 iPhone von Wolfgang Martin Wieland: explain how this is how, by introducing external fields that then lock the particles in certain trajectories, it is possible to make this approximations I think this. 651 01:16:44,370 --> 01:16:45,180 iPhone von Wolfgang Martin Wieland: This would be nice. 652 01:16:45,210 --> 01:16:45,720 Christodoulou Marios: To sync. 653 01:16:47,100 --> 01:16:50,430 Christodoulou Marios: explicitly the magnetic field, be that is somehow. 654 01:16:50,460 --> 01:16:58,470 iPhone von Wolfgang Martin Wieland: coupling your trap or whatever that that moves the particles in some external feel that that makes it. 655 01:17:00,750 --> 01:17:01,650 iPhone von Wolfgang Martin Wieland: yeah this is. 656 01:17:01,680 --> 01:17:02,790 Christodoulou Marios: This, I think that it. 657 01:17:02,790 --> 01:17:06,330 Christodoulou Marios: makes it possible for me to couple this. 658 01:17:06,330 --> 01:17:07,770 Christodoulou Marios: field, the with the. 659 01:17:09,330 --> 01:17:10,710 Christodoulou Marios: know your thing. 660 01:17:12,510 --> 01:17:17,190 iPhone von Wolfgang Martin Wieland: And then you can explain why they are heavy degrees of freedom that you can just. 661 01:17:18,570 --> 01:17:20,310 iPhone von Wolfgang Martin Wieland: That just follow the classic. 662 01:17:26,310 --> 01:17:28,140 iPhone von Wolfgang Martin Wieland: OPS or expect now. 663 01:17:30,690 --> 01:17:33,480 iPhone von Wolfgang Martin Wieland: But in any case, we should continue this. 664 01:17:36,990 --> 01:17:37,320 iPhone von Wolfgang Martin Wieland: Actually. 665 01:17:41,220 --> 01:17:41,610 Ivan Agullo: Is. 666 01:17:41,670 --> 01:17:44,280 Ivan Agullo: And let me take the chance that you are here to ask you. 667 01:17:45,570 --> 01:18:00,810 Ivan Agullo: Your opinion about the question you mentioned at the beginning of your talk this controversy about the fact about the fact that a if our interaction, maybe it's entanglement, it must be a quantum interaction. 668 01:18:02,190 --> 01:18:03,270 Ivan Agullo: What is your opinion about that. 669 01:18:11,850 --> 01:18:13,440 Ivan Agullo: You have an opinion or. 670 01:18:14,130 --> 01:18:17,490 Christodoulou Marios: I do, I think it works, and I think it. 671 01:18:19,200 --> 01:18:25,140 Christodoulou Marios: Does witness not very much, but something about something above nothing. 672 01:18:26,280 --> 01:18:28,860 Christodoulou Marios: It does tell you that it can be a classical field. 673 01:18:30,210 --> 01:18:34,140 Christodoulou Marios: I think, after all this time thinking about they still haven't found exactly the words. 674 01:18:34,320 --> 01:18:37,050 Christodoulou Marios: To say because it does get very confusing. 675 01:18:38,160 --> 01:18:39,840 Christodoulou Marios: I think what is. 676 01:18:41,250 --> 01:18:48,150 Christodoulou Marios: Being overspent was too strong statement is the theory independent so whether they want to say. 677 01:18:49,500 --> 01:18:52,260 Christodoulou Marios: You have two systems and they get entangled. 678 01:18:53,850 --> 01:19:03,810 Christodoulou Marios: By some third system, I assume locality interactions thus whatever theory might be describing this interaction, it must be something based on a non classical field. 679 01:19:04,680 --> 01:19:16,470 Christodoulou Marios: I do not see that you can do that in these experiments, I mean it's it's so just to make sense of what all this means to see what fixed entire theory here and we're still don't understand so. 680 01:19:18,180 --> 01:19:21,120 Christodoulou Marios: You know your belt test, which is a theory it independent. 681 01:19:22,740 --> 01:19:33,000 Christodoulou Marios: test is just under statistics statistics and you say you know, cannot be this type of theories that describe this effect, I think that's too strong. 682 01:19:49,470 --> 01:19:50,130 Christodoulou Marios: speaker again. 683 01:19:54,510 --> 01:19:56,340 Christodoulou Marios: Thank you, thank you very nice discussion.