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How Space and Time Could Be a Quantum Error-Correcting Code
- jchrisa 8y agoJust came to say it makes me happy to see the term "discovered" used in a what is essentially an engineering/software context, instead of the term "invented." The more that people in our industry speak clearly about that fact that many of the constraints in our problem space are universal, and thus much of our solution space is discovered, not invented, the more we shift the culture to understand e.g. the absurdity of software patents, etc.
- izzydata 8y agoDo they use a similar terminology in mathematics when talking about proofs? Software solutions don't seem that much different in regards to solving specific problems.
- gregknicholson 8y agoThis question — is maths discovered or invented? — was discussed at length in a recent BBC series: https://www.bbc.co.uk/programmes/b0bn9dth https://www.bbc.co.uk/programmes/b0bn9dth
- darkerside 8y agoI wonder if there are languages where there is no real dichotomy between these two terms
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- wlib 8y ago"Invent" comes from Latin and simply means "find". If you think about it, no matter what language, there is no fine line. An invention is just a discovery, but we typically use the word to describe a very specific discovery.
- wallace_f 8y agoWell I always thought there was a fine line: an invention must be brought into existance witj intelligent design (probably by a human), and a discovery exists naturally.
- darkerside 8y agoThe English language often has multiple synonyms with a difference in connotation. Discover and invent may be synonyms (although many would disagree), but everybody would agree at least the connotation is different. My hypothesis above was that there may be languages where that connotation does not exist.
- wallace_f 8y agoa YT link to ep 1: https://youtu.be/cyvDG8qjt-M https://youtu.be/cyvDG8qjt-M
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- inopinatus 8y agoAll matter is information, and all information is functional. Therefore perception is the lazy evaluation of the universe, and discovery is the fountain of invention.
- mttyng 8y agoThat depends heavily on your philosophical interpretation of mathematics: Platonism vs. Formalism Someone linked the BBC video, which is great, but there’s also a wonderful book that discusses this and many other facets of mathematical philosophy: https://www.amazon.com/Thinking-about-Mathematics-Philosophy/dp/0192893068/ref=mp_s_a_1_1?ie=UTF8&qid=1546551558&sr=8-1&pi=AC_SX236_SY340_QL65&keywords=philosophy+of+math+shapiro&dpPl=1&dpID=41a3oT4rENL&ref=plSrch https://www.amazon.com/Thinking-about-Mathematics-Philosophy... (Sorry for the link spew) I highly recommend that book to anyone remotely interested in the field.
- kiliantics 8y agoPenrose also dedicates a chapter to this in The Road to Reality
- jessriedel 8y agoNot sure if it was rhetorical, but to answer your actual question: Mathematicians often say they "discovered" or "found" a proof. I've never heard one say they "invented" a proof, although they might talk about "building" a formalism or framework.
- ashleyn 8y ago"Discovered" in place of "invented" is actually cited as a common error in many English style guides.
- malloryerik 8y agoUnconvinced, with respect. Patents and systems of intellectual property are also codes that create space and time, in this case financial. Without them, scientific and engineering discovery/invention has often (usually?) tended to collapse in on itself.
- stronglikedan 8y agoI inferred that OP was referring to the absurdity of the current software patent system and not the idea of patenting IP directly, and I agree that the current system is in dire need of an overhaul.
- malloryerik 8y agoThat's fair. I surely agree that poorly made IP codes can also inhibit discovery and invention. And the article notes that the corrective time-space codes are "a lot smarter than us."
- jonbesga 8y agoDo you have a source to read about this? Seems an interesting topic.
- malloryerik 8y agoThe analogy just came to me, really. Maybe some basic IP theory, or economic history? https://www.nature.com/articles/538456a https://www.nature.com/articles/538456a
- zzbzq 8y agoThe etymological roots of "discover" and "invent" converge.
- dclowd9901 8y agoI'm not sure I really understand the article, as it is, but space-time seemed preternaturally a macrocosm of the quantum universe, a way to smooth out the infinitely possible subspace into a predictable and understandable macro space, the collapsing of all possible realities at the atomic level into a definite reality. In other words, this seems too obvious to be this obvious, so what am I missing here?
- vtomole 8y ago>What am I missing here? It's not obvious how to reconcile the laws quantum mechanics with gravity and vice-versa as they seem to make incompatible descriptions of reality.
- notduncansmith 8y agoMandelbrot cosmology offers some interesting potential resolutions, but more research definitely needs to be done.
- airstrike 8y ago> The bendy fabric of space-time in the interior of the universe is a projection that emerges from entangled quantum particles living on its outer boundary. Guess we are living in a simulation, after all. A quantum one, to be precise.
- kamac 8y agoWow that was a tough read for a layman like me. > [...] after the renowned physicist Juan Maldacena discovered that the bendy space-time fabric in its interior is “holographically dual” to a quantum theory of particles living on the lower-dimensional, gravity-free boundary. What does "holographically dual" mean? What boundary are we talking about here? > The bendy fabric of space-time in the interior of the universe is a projection that emerges from entangled quantum particles living on its outer boundary What is the "interior" of the universe? What is the "outer boundary"?
- toufiqbarhamov 8y agoThere isn’t an exterior in this model, just a boundary you can’t get “outside of” because everything including space and time are part of the universe. What this is all based on is the observation that the information required to describe the volume of (for example) a black hole, can be encoded on its event horizon. The theory says that the universe and it’s horizon(s) can be similarly modeled. In essence that we live not in the volume of a soap bubble but in the fluctuations of the skin of the bubble. It’s only to us, at our energy level and scale that a higher dimensional volume appears to emerge. It’s important to say that this is all entirely speculative, based on the physical possibility which allows for the resolution of some outstanding problems in physics. That doesn’t mean it is in any way real, it is just another possible model, and one without observation to support it as the way our universe actually works.
- wallace_f 8y agoPerhaps a stupid question: If a 3d universe can be encoded in a 2d space, then I suppose a 2d universe can be in a 1d space? And could 1 dimeneion be encoded in 0? Just some bits or fluctuations?
- saalweachter 8y agoWith the caveat that I am neither a physicist nor a mathematician: 1. My understanding is that some kinds of 3d universes can be encoded on a 2d surface. Whether our universe is one of those is an area of research. 2. You can't always generalize from one dimension to another in mathematics. The most common example is that knots can only exist in three dimensions; they don't exist in 2 or 4.
- jfhufl 8y agoThe only reason I have any vague understanding of this article is all thanks to PBS Space Time on Youtube. It's an amazing series. Must watch if you want to know how much we humans understand about our universe.
- wallace_f 8y agoOr equally fairly, how much we dont understand. One of the reasons I like that series is they seem intent to do some justice to competing theories and the fact that we still don't really have a working model of the universe, or know answers as to why theories work the way they do. Anyways this article was a really hard read for me. It's like the relatively-readable paragraphs are laughing at me--written like I should be understanding them, but I don't, ie: >The best error-correcting codes can typically recover all of the encoded information from slightly more than half of your physical qubits, even if the rest are corrupted. This fact is what hinted to Almheiri, Dong and Harlow in 2014 that quantum error correction might be related to the way anti-de Sitter space-time arises from quantum entanglement.
- earthicus 8y agoI'd also like to recommend the semi-technical talks by Nima Arkani-Hamed and Leonard Susskind. They are the only reason I have the faintest hint of what is going on in theoretical physics and cosmology.
- jgrowl 8y agoI caught a physics bug several weeks ago and finding PBS Space Time was exhilarating. I would also highly recommend it.
- joemag 8y agoSpace Time is fantastic. Upon watching the entire series (catching up to present time, to be more exact, since new episodes are still being released weekly), I went on a graph traversal spree of related YouTube videos. Another great series I loved was from Fermilabs, with Dr. Don Lincoln.
- jcoffland 8y ago> But a fundamental problem stood in the way of actually building quantum computers: the innate frailty of their physical components. It's entirely possible that there is some sort of physically limiting factor that makes it nearly impossible to entangle more than X qbits. Something akin to Amdahl's law for quantum computing. It wouldn't be a very sexy result.
- perl4ever 8y agoI'm thinking of the infeasibility of building a rocket to get off a large planet (compared to earth). The intuition of a layperson is a bad guide, but I've always had the gut feeling that quantum error correction would prove to be exponentially difficult to scale. If smart people think otherwise, I can hope they're right, but I wouldn't bet money on it until I find an explanation I can grasp. It just sounds like a free lunch, or cold fusion.
- kerenua 8y agoI feel I don't have enough background information to understand this article. >...space-time in the interior of the [anti-de Sitter] universe is a projection that emerges from entangled quantum particles living on its outer boundary A projection? How would this differ if the quantum particles on the outside were not entangled? >holographic “emergence” of space-time works like a quantum error-correcting code. holographic in what way? and how is this similar to error correcting code? >quantum error correction explains how space-time achieves its “intrinsic robustness,” what is an example of this robustness in space-time? >...error-correcting codes can recover the information from slightly more than half of your physical qubits, even if the rest are corrupted. This fact that hinted quantum error correction might be related to the way anti-de Sitter space-time arises from quantum entanglement. how does the effectiveness of error correcting codes, being able to recover information despite 50% corruption, explain space-time? if anyone could point me in the right direction, I'd really appreciate it. I find this interesting and important but am not smart enough to comprehend it.
- tbabb 8y agoIn quantum physics and cosmology, "holographic" (and "projection", in this context) are related to the holographic principle, which is kind of like a Stokes' theorem for information-- it says that specifying the state of the universe on the boundary of a manifold is sufficient to completely specify the state inside. If someone's read the full paper, maybe they can explain the other things-- this article is a bit too vague.
- kerenua 8y agoroywiggins said >you have a universe that is infinite from "inside", but "from the outside", there's an outer boundary. and you say >specifying the state of the universe on the boundary of a manifold is sufficient to completely specify the state inside this would be similar to me viewing a Mandelbrot set and being able to tell its infinitely deep?
- tbabb 8y agoMaybe a better analogy would be: If you know the complete state of the universe at one moment in time, you know the state at all moments in time, because you can run the laws of physics (forward or backward) and compute the state at some other time without adding information. (In physics, this arises from a property called "unitarity"). The holographic principle says you can do the same thing, but by knowing the state of the universe on a boundary that encompasses the whole system (when you parameterize spacetime in a convenient way), as opposed to by knowing the state everywhere at one moment.
- vtomole 8y agoThe study of Black Holes with the lens of Quantum information has been an exciting sub-field of Physics for the past couple of years. If you are curious about it, I recommend Patrick Hayden's "The Quantum Computational Universe" lectures [0][1]. The first one is an introduction to Quantum computation and the second one is more in line with what this Quantamagazine article is about. [0]: https://www.youtube.com/watch?v=AqWuyeh0SxQ https://www.youtube.com/watch?v=AqWuyeh0SxQ [1]: https://www.youtube.com/watch?v=F6vGAiMz5kQ https://www.youtube.com/watch?v=F6vGAiMz5kQ
- yetihehe 8y agoIt reminds me of old quote "Time is what keeps everything from happening at once" [1] and similar "Space is what keeps everything from happening in the same place". [1] https://skeptics.stackexchange.com/a/30402 https://skeptics.stackexchange.com/a/30402
- Bombthecat 8y agoNice, feels like we are getting closer.
- baron816 8y agoI have a feeling I would get a brain aneurysm if I tried to read this.
- joycian 8y agoCould someone explain to me why we should look into this, because we do not live in an anti-deSitter universe. So what is the relevance (beyond the obvious mathematical curiosity and elegance)?.
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- chrispeel 8y agoMy understanding (from Patrick Hayden) is that in the center of AdS space, things look very much like normal space. Physicists are working in AdS space because they can actually do some analysis there, even though they would very much like to work in de Sitter space.
- roywiggins 8y agoIt's a toy model, but the hope is that the insights gained by playing with it will apply to ours: "On the physics side, it remains to be seen whether de Sitter universes like ours can be described holographically, in terms of qubits and codes. “The whole connection is known for a world that is manifestly not our world,” Aaronson said. In a paper last summer, Dong, who is now at the University of California, Santa Barbara, and his co-authors Eva Silverstein and Gonzalo Torroba took a step in the de Sitter direction, with an attempt at a primitive holographic description. Researchers are still studying that particular proposal, but Preskill thinks the language of quantum error correction will ultimately carry over to actual space-time." Also, black holes at least superficially have a spatial boundary (the event horizon) so perhaps you can model what happens inside using the holographic principle.
- planck01 8y agoFor the same reason as why biologist spend a lot of time studying E. Coli, fruit flies and mice (besides being interested in them in themselves). It's because those organisms are similar enough to humans, but still a lot simpler to study. In this way we get important clues and ideas of how stuff might work for human cells, which is still very hard to work out and prove, but is a lot easier than just starting in the dark with human cells.
- darkerside 8y ago> That year — 2014 — three young quantum gravity researchers came to an astonishing realization. They were working in physicists’ theoretical playground of choice: a toy universe called “anti-de Sitter space” that works like a hologram. Wow, so we truly are in a simulation Edit: Sorry, I thought this was a funny play on ambiguous words, but apparently HN disagrees!
- danbruc 8y agoNo, not that we know.
- perl4ever 8y agoYou will often get downvoted for humor on HN. On the other hand, I have at times gotten double digits worth of karma for a humorous post. I guess you have to appeal to a certain type of person.
- darkerside 8y agoYeah, I've definitely noticed. Guess I can't help taking a gamble on occasion. On this particular occasion, I truly couldn't tell if my joke was a whoosh, or just not funny! I made myself laugh, but that's not difficult.
- mkaziz 8y ago> Ahmed Almheiri, Xi Dong and Daniel Harlow did calculations ... It's pretty cool to see a Westerner, Middle Easterner and an East Asian dude (at least based on names ...) collaborate to push the frontiers of science like this!
- ralusek 8y agoThis happens literally all the time. This is probably more common than uncommon.
- vorg 8y ago> Westerner, Middle Easterner and an East Asian [...] based on names This international variety of names is common outside the English-speaking world, e.g. the 3 biggest internet companies in China (Alibaba, Tencent, Baidu).
- xchip 8y agoI'm wondering how many physicists roll their eyes each time they see similar extraordinary headlines like this one edit: I am a physicist.
- joe_the_user 8y agoWell, I think a lot of folks here find the description strange and opaque - I studied a bit differential geometry for my math degree and this seems way up there. I'd love to hear why a physicist would roll their eyes at this.
- dsnuh 8y ago>So, how do quantum error-correcting codes work? The trick to protecting information in jittery qubits is to store it not in individual qubits, but in patterns of entanglement among many. So are quantum encoding patterns the Proof Of Work of multidimensional holgraphic blockchains? Edit: accidentally pasted entire article
- maggots 8y agoGee, sounds like a theory seeking facts. Isn't it supposed to work the other way around? You know, math is really great and all, and you can transform a sphere into a torus, but meat doesn't transform into flies.
- osrec 8y agoHow I understand it: The world around us is some sort of "projection" of stuff at the very edges of our universe, and that stuff is inherently fragile and unstable. Yet our world/reality/spacetime is not fragile and unstable - quite the opposite, despite being dependent on that fragile stuff in the first place. Thus it must somehow be "correcting" for the intrinsic instability of the stuff on the outer edges that gives rise to our reality. Therefore it is in some sense an error correcting code. Happy to be corrected by those with a deeper understanding!
- neom 8y agoThe world science festival has a good video about this: https://www.youtube.com/watch?v=HnETCBOlzJs https://www.youtube.com/watch?v=HnETCBOlzJs - The "correction" could very well be reconciliation, the output of what plays out in the program + the program is procedurally generated based on the outputs. Another good talk is this one by John Preskill from 2015: https://www.youtube.com/watch?v=SW2rlQVfnK0 https://www.youtube.com/watch?v=SW2rlQVfnK0
- jhuni 8y agoThis makes error-correcting the foundation of the universe, but I would prefer to have causality be fundamental, such as with the causal sets program. This is interesting though, especially for quantum computing.
- ziont 8y agodoes this mean that out of all the possibilities space and time brings about order and chaos?
- luc4sdreyer 8y agoAwesome idea, but is there any way to test the hypothesis? Or will it be forever locked in the box of "extremely elegant but untestable" along with string theory?
- dmurthy 8y agoCurious what are the logic gates made of? What kind of engineering does it take to build the gates?