Eternal Change for No Energy: A Time Crystal Finally Made Real https://www.quantamagazine.org/first-time-crystal-built-using-googles-quantum-computer-20210730/
On 7/26/21 7:59 AM, uǝlƃ ☤>$ wrote: > No, thanks very much for the transcript. Time as updating is an old concept. > So, it's not clear to me that they're talking about anything new *there*. But > they sound a bit wrong to me in decoupling the updating from the *subgraph* > that gets updated as well as any kind of causal cascade of updating > (dependent/sequential vs. independent/parallel). You can't separate > dependency from the graph. So if there is a dependent update in one part of > the graph, dependent on another part of the graph, then the updating cannot > be independent of the graph. I.e. space and time are not independent and, > perhaps, not different things at all. Perhaps progressive updating is > *merely* that the graph has large scale cycles? So, an updating over there > drives an updating here, which drives an updating over there? > > Of course, they're way smarter than me. So I'm sure there's some deep > literature somewhere and I should, but probably won't, RTFM. > > > On 7/23/21 6:32 PM, Jon Zingale wrote: >> Anyway, I hope including the transcript here was not too boring. > > [reordered rather than snipped] > >> Thank you for looking into it. Yes, that is the publication. Also, thank you >> for posting "The post-truth prophets"[0]. Sean Illing manages to get at the >> heart of what I find myself defending regarding postmodernism[1]. You may >> remember that some months ago, I was on a "Bergson through the eyes of >> Deleuze"-kick. Bergson, a prominent philosopher of mind, space, and time (in >> his time) was driven completely underground by Einstein, Russell, and other >> promoters of relativity theory. By many historical accounts, the work of >> Bergson could have been all but forgotten had Deleuze not resurrected his >> ideas, and especially their applications to film. Crucial to Bergson's >> conception was to recognize time and space as explicitly different kinds of >> things, and via his admiration of Riemann, sought out but never found a >> mathematical treatment for his ideas. Listening to Wolfram's interview on >> Sean Carroll's podcast[2], I cannot help but wonder if this recent work is a >> step toward Bergson's >> dream. Around 42 minutes into the interview, SeanC and SteveW record: >> >> """ >> 0:41:26.7 SW: That is, you might have thought to get something as >> computationally sophisticated as us humans with our brains and all this kind >> of thing you need the whole process that’s led to us humans. But what the >> principle of computational equivalence says is that’s not true. Even these >> very simple systems with very simple rules can do it, and that has… Well, it >> has lots of consequences. If you’re worrying about extraterrestrial >> intelligence, for example, that tells you it’s everywhere. It’s a question >> of whether we are sufficiently aligned with that intelligence to be able to >> recognize it as something that, for example, has purposes that we can >> understand as sort of human-like purposes. And I think this idea >> intelligence requires liquid water is almost laughable. >> >> 0:42:10.2 SC: Right. [laughter] I’m on your side when it comes to that, but >> intelligence might require spacetime in some sense, so let’s at least try to >> get that. Is this naïve picture that I have in mind, where you have the >> hypergraph, you update, it’s a discrete updating… Can I think of the graph >> at any one update as space and the update itself as time, or is that too >> simple-minded? >> >> 0:42:35.3 SW: Okay, so it gets a little complicated. And in fact, the >> complexity that arises is quantum mechanics, I think. And so it’s, in a >> sense, you try and make it that simple and you… Okay, so the basic point is, >> the rule says if you have a lump of atoms of space that are connected in >> this way, transform it into a lump that’s connected in this other way, and >> it… Basically the rule just says that’s what you do. It doesn’t say where >> you do it, it doesn’t say when you do it, it’s just any time there’s a lump >> that looks like this, you can transform it into a lump that looks like that. >> >> 0:43:11.0 SW: And so those transformations can be happening all over this >> hypergraph. And so it is not at all obvious that… That is, the only thing >> that’s defined is these can happen. The question of when they happen, what >> counts as the sort of simultaneity surface, what counts is that moment in >> time, is something that’s really in the eye of the observer. >> >> 0:43:31.7 SC: Okay. But the updated graph is supposed to represent spacetime >> and the things within it, or is it a more subtle map there? >> >> 0:43:37.9 SW: No, no. So at any given… What’s happening is this graph is >> getting updated, and there are lots of little places where it can get >> updated. And you can say, okay, I’m going to consider the graph with this >> collection of updates having been done. I’m going to consider that as time T >> equals 0, let’s say. And then another situation you’re going to say, now, >> I’m going to say this collection of updates is time T equals 1, for example. >> And at each one of those time slices, at each one of those sort of… Well, in >> the language of physics, spacelike hypersurfaces, that represents an >> instantaneous structure of space. But it is somewhat arbitrary what you >> consider to be this instantaneous structure of space, just as it is in >> general relativity. >> >> 0:44:26.9 SC: Well, sure, right. I mean, that’s very familiar from general >> relativity, but I’m just saying is the collection of the whole shebang >> spacetime, and the things within it? >> >> 0:44:35.0 SW: No. It’s just space. A single hypergraph, a single… >> >> 0:44:37.6 SC: No, the collection of all the updated hypergraphs, that’s what >> I’m asking. >> >> 0:44:40.2 SW: Oh, yeah, yeah. Right. The sequence of updates, the hypergraph >> together with all its updates is supposed to be spacetime. And one of the >> things that is interesting and non-trivial here is most traditional views of >> physics have thought of space and time as being the same kind of thing. In >> this model they’re really not. >> >> 0:45:00.0 SC: Sure. >> >> 0:45:00.0 SW: Space is the extent of the spatial hypergraph. Time is the >> computational process of updating this hypergraph. So time is the >> progression of a computation. Space is just, oh, you follow these >> connections in the hypergraph. And so that makes it not at all obvious that >> you’re going to get things like relativity out of the model, because one is >> breaking apart the traditional connection between space and time. >> """ >> >> Anyway, I hope including the transcript here was not too boring. >> >> Cheers, >> Jon >> >> [0] >> https://www.vox.com/features/2019/11/11/18273141/postmodernism-donald-trump-lyotard-baudrillard >> >> <https://www.vox.com/features/2019/11/11/18273141/postmodernism-donald-trump-lyotard-baudrillard> >> >> [1] The other part is that this considerable body of work was the >> result of serious thought by powerful thinkers. Discounting the whole >> body of literature out of hand produces red flags for me. >> >> [2] >> https://www.preposterousuniverse.com/podcast/2021/07/12/155-stephen-wolfram-on-computation-hypergraphs-and-fundamental-physics >> >> <https://www.preposterousuniverse.com/podcast/2021/07/12/155-stephen-wolfram-on-computation-hypergraphs-and-fundamental-physics> >> > > -- ☤>$ uǝlƃ - .... . -..-. . -. -.. -..-. .. ... -..-. .... . .-. . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn GMT-6 bit.ly/virtualfriam un/subscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ archives: http://friam.471366.n2.nabble.com/
