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How the Physics of Nothing Underlies Everything
- beefman 4y agoOriginal source: https://www.quantamagazine.org/how-the-physics-of-nothing-underlies-everything-20220809/ https://www.quantamagazine.org/how-the-physics-of-nothing-un...
- a_t48 4y agoI can’t be the only one who gets some pangs of anxiety reading about this stuff
- senectus1 4y agoNot being an American, and watching the events in America and American politics has helped me realize there is some things i have Absolutely no control over.. and if I have no input or control over it then there is no reason for me to get stressed about it. Physics is one of those things. its too big and far away for me to stress about it. If its gonna kill me I cant stop it.. I might as well enjoy what I do have control over.
- quickthrower2 4y agoPhysics does indeed kill all of us
- NateEag 4y agonah, physics just describes processes from reality. It's the universe that kills us.
- curtainsforus 4y agoBiology kills us first, and in a manner that's contingent, not necessary; there are universes with physics similar to ours where life could continue forever. (Just add some rare non-energy-conserving interactions to be exploited). Eventually, over 10^100 years of operation you get into interesting problems with the number of possible states a mind of a given size has being finite; but if you can continually add more matter via non-energy-conserving interactions, you could add more memory/processing up to fundamental physical limits: you can only fit so much information in a given volume before it collapses into a black hole; you can only communicate at c, so if you make your mind bigger, it has to parallelize or slow down; Given the expansion of space, at some scale, light signals from one end of your mind can't reach the other (the space inbetween expands faster than C), which would be the the fundamental limit... except that gravity counteracts the expansion of space, and I'm not sure what the expansion properties of a visible-universe-filled volume of just-barely-black-hole-subcritical computronium is. I imagine you're in a big crunch regime at that point, except... Isn't that the same thing as a black hole collapse? Nonetheless, there's presumably some balancing density that perfectly avoids both expansion and contraction, though it's presumably unstable. Ignoring the instability-difficulties, though, that means you can continue growing the amount of memory you have by slowing down your processing speed to one clock cycle every ~2*the diameter of your mind in light-years years. I'm not sure what the ultimate limiting factor is here, given infinite time; does the amount of computation of this system in infinite time go to infinity as your scale goes to infinity, or does it asymptotically approach some finite upper bound?
- drraj32 4y agoCan you explain the reason for anxiety? I read through first few paragraphs where author talked about vacuum. "Nothing" about it is anxiety inducing. But then, I grew up in the subcontinent where the ancients postulated that everything came from Shunyata (nothingness).
- a_t48 4y agoI think it’s just imagining how big the universe is…and then imagining that, but multiplied with space in between. The possible collapse of it all is a fun bonus.
- Cthulhu_ 4y agoA kind of megalophobia? Mixed with what cosmic horror invokes, the feeling that you are nothing in an indifferent universe. Knowing just enough about the universe to know you are nothing.
- barrenko 4y agoUniverse is not exactly indifferent. Neither indifferent nor not-indifferent. David Deutsch offered some consolation to me, because when you take in account multiple dimensions there is also a vast quantity of Earths out there "somewhere".
- mensetmanusman 4y agoThe idea that there are multiple parallel earths is fun to think about, but know that it is an unfalsifiable hypothesis and arguable is outside the realm of science (and close to the realm of meta-physics).
- mistermann 4y agoIs this knowledge particularly useful in some way in this case? Does it prompt any particular action in response?
- lvncelot 4y agoHave you ever "played" Space Engine? Zooming around the universe with a speed approaching megaparsecs always induces a sinking feeling in my stomach and a sense of insignificance, and it's a little bit what I'd imagine the Total Perspective Vortex from The Restaurant at the End of the Universe would feel like.
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- hypertele-Xii 4y agoTo me it feels like home. I'd love to be a particle zooming across the vast cosmos at light speed. Some of the best dreams I've ever seen.
- pixl97 4y agoUnfortunately if you were moving light speed you wouldn't experience time, so it would be rather less eventful than you imagine. If you kicked it down just below light speed existence would be a bright white/blue spot in front of you.
- danbruc 4y agoWith lightspeed you are going pretty much nowhere. If you are flying through intergalactic space zipping past galaxies you are probably at least going trillions or quadrillions times the speed of light. Even just crossing the Milkyway would take you a hundred thousand years.
- quickthrower2 4y agoreading the selfish gene also does this - “you can’t handle the truth” applies to all of us!
- tasty_freeze 4y agoI'm in the mood to nitpick: > In a theatrical demonstration in 1654, he showed that not even two teams of horses straining to rip apart the watermelon-size ball could overcome the suction of nothing. In fact, there is an addendum saying the article originally said grapefruit, then updated it to watermelon. Say the watermelon had a diameter of 10 inches, or a cross section of 78.5 sq in. Atmospheric pressure is 14 psi. The force of the vacuum would be 78*14, so 1100 lbs. Impressive, but it seems like a horse could possibly generate that much instantaneous pull. This site [0] says horses can pull six times their body weight for short pulls! That leads me to believe the sphere was bigger than a watermelon, and in fact, the drawing of the affair shows a sphere about the size of a beach ball. [0] https://horserookie.com/how-much-weight-can-a-horse-pull/ https://horserookie.com/how-much-weight-can-a-horse-pull/
- sigmoid10 4y agoThe actual sphere was 20 inches, but the quality of the vacuum they were able to create is unknown. So it could be a lot less than the theoretical max of 2200lbf. You can see a picture of the original and its measurements here (they are in a museum in Munich): https://en.m.wikipedia.org/wiki/Magdeburg_hemispheres https://en.m.wikipedia.org/wiki/Magdeburg_hemispheres
- rcxdude 4y agoIt could be a very poor vacuum by most standards and still have 90% of the force of a perfect vacuum. You get an impressive sealing force very quickly as soon as you can create any pressure difference.
- sigmoid10 4y agoOnly if the surface area is big enough. If you only have 1 square inch plates, even a complete vacuum would only net you 14.7 lbs of force - something most people could separate with their hands. But 10 inch side-length plates would already be impossible to separate for almost all humans, even at half atmospheric pressure between the plates.
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- acqbu 4y agoWhy is there something rather than nothing? Why is there anything at all?
- kekebo 4y agoIf you consider existence / non-existence as a quantum superposition you'll have 0 observers and thus no entanglement in the non-existing branch and basically get existence for free. Maybe existence just happens to be the default. Joscha Bach has more elaborate thoughts on this.
- quickthrower2 4y agoWhy do we get the quantum entanglement instead of “nothing”?
- namero999 4y agoWhy is a terrible question when dealing with the reduction basis :)
- layer8 4y agoI suspect that there isn’t just something, but that actually there is everything — all possible worlds, or maybe more formally, all logically consistent structures. In other words, there is no difference between existence and possibility. The answer to why there is anything then boils down to “because it can”.
- lvncelot 4y agoYes, this puts something I believe rather nicely. I think this applies to every mathematical structure, and that, in a sense, the number 3 and my desk exist on the same conceptual level of reality. (Only one is a tad more complex than the other).
- kleene_op 4y agoIt is actually the most elegant answer to why we're here. I know Occam's razor is not a valid scientific argument, but supposing that everything just exists removes the arbitrariness of it all, our subjective view of the world in particular. It's the simplest explanation of it all. I also believe that the simplest axiomatization of this theory would be a paradox. From a false postulate, any true (and/or false) statements can be derived. Including that which describes/corresponds to our reality. It only takes 0 == 1 for everything to exist, but that's something we cannot logically prove, nor use at our advantage. It's a useless theory of everything, but a neat one.
- kbrkbr 4y agoThere is a nice popular science movie called Everything And Nothing, „starring“ Jim Al-Khalili that tells a similar story (without involving string theory). My kids loved it.
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- zvrba 4y ago> he showed that not even two teams of horses straining to rip apart the watermelon-size ball could overcome the suction of nothing. Um. It's not "suction of nothing", it's the pressure of the atmosphere. If the vacuum-"filled" ball were put into another vacuumed container, a small child would have no trouble separating the halves.
- pixl97 4y agoIf the balls were made of very smoothly polished metal would that be true? https://en.wikipedia.org/wiki/Cold_welding https://en.wikipedia.org/wiki/Cold_welding
- MisterTea 4y ago> If the vacuum-"filled" ball were put into another vacuumed container, a small child would have no trouble separating the halves. Hell, they would likely come apart on their own due to a low pressure differential and gravity pulling at them.
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- meltyness 4y agoTo attempt to summarize the touchstones from a microscopic, and macroscopic approach, force conception of pressure -> modern physics and qft, Higgs field implies non-vacuum -> kaluza klein and string theory compactified dimensions -> it's actually a theory for each vacuum state -> the anthropic principle -> some vacuum states hypothesized to destroy spacetime vvv https://journals.aps.org/prd/abstract/10.1103/PhysRevD.104.L121701 https://journals.aps.org/prd/abstract/10.1103/PhysRevD.104.L... ^^^ a dark energy description by de Sitter <- the observation that the universe is undergoing accelerated expansion <- the multiverse hypothesis <- the anthropic principle
- wingspan 4y ago> “And Knosso whatever-his-name was a physicist. That’s the Library of Nothing.” > “Nothing?” > The old woman had her spiel ready. “Physicists long since determined that most of space was empty, and most of each atom was empty, so that the overwhelming nature of the universe is nothingness, with tiny interruptions that contain all of existence. So their library is named for this Nothing that comprises most of the universe. And the mathematicians share the space, because they are proud to say that what they study is even less real than what the physicists study, so their portion is called the Library of Less than Nothing.” > Rigg decided he was going to like the physicists. It seemed to him, though, that the mathematicians must have an annoying competitive streak. Pathfinder (2010) by Orson Scott Card
- zoomablemind 4y ago"...If so, the good times won’t last forever." "...Don’t panic. Even if our vacuum is only metastable, given its staying power so far, it will probably last for billions of years more." Ooph, such a wild ride an article! No wonder a participating scientist, as mentioned, has worked himself to a disturbing need to seek therapy. Reading this, it seems that the science is very comfy operating with time concept as we know it, projecting its flow into the 'billions of years' into the future. Time as a sole witness to truth and to the human struggle to comprehend its own destiny. But could this time too be a temporary or a even dynamic state or even a dimension itself?
- micheles 4y agoSpeaking as a physicist, I have always hated this nomenclature. There is no vacuum at all. The universe is filled with quantum fields, they are the source of the Casimir effect. Terms as "vacuum energy" are simply a bad naming, the energy comes from the quantum field, which is a very physical object even if not intuitive, as anything quantum.
- dumbworld 4y agoI think the quantum universe is simply too difficult to perceive for most people. If you begin to talk about quantum biology or get into specifics like the Vaidman bomb tester or how information propagates logically, most times I’ve either been accused of being mentally ill or not knowing what I am talking about. I think the key mistake is expecting others to operate at a conscious and curious level.
- As_You_Wish 4y agoI don't really think that it is too difficult. It's like that saying that is around - if you can't explain something simply, then you really don't know the topic well. As Einstein explained relativity to the general public: “When you sit with a nice girl for two hours you think it’s only a minute, but when you sit on a hot stove for a minute you think it’s two hours. That’s relativity.” Just use an analogies. Analogies are best, even if they are not 100% accurate, which I guess is the point of analogies - to use something one knows to illustrate a new concept. To explain, I would tell them that the analogy I'm giving is not exact, but a way to get a general idea. So for quantum fields, one possible way is to explain it like an ocean. I would say that a quantum field can be understood as an ocean that covers the entire universe but too small to see, just like atoms. But it's still there. And, there are 24 of these oceans all overlapping each other, for each type of field, like one for electrons, one for the photons, etc. A photon comes into existence in this ocean when it is excited, similar to a wave on an ocean. This means that there is no such thing as "empty space" or a complete vacuum, it is impossible, the quantum fields permeate everything everywhere. That's pretty simple to understand, even for a 10-year-old. Maybe there are better analogies. I'm just using this as one such example, showing how to explain a topic, rather than the topic of quantum fields specifically, although the explanation above does that, too. On youtube, there are great videos that show how this is done, just search on "explain in 5 different levels of complexity". I think you will be fascinated! :) Here is the search results for it in youtube: https://www.youtube.com/results?search_query=explain+in+5+different+levels+of+complexity https://www.youtube.com/results?search_query=explain+in+5+di...
- the-mitr 4y agoOf possible interest https://archive.org/details/PodolnySomethingCalledNothing https://archive.org/details/PodolnySomethingCalledNothing
- inphovore 4y agoThis is a miscomprehension. The underlying aspect of existence is universal potential. All existent reality is a perturbation of universal potential distributing as an “aspect” of existential being. This nothing being observed is actually the distribution of potential acting upon itself. The “space between” existent potential is the potential acting upon neighboring potential. So where “nothing” is observed, it is actually the field separation of the discrete potential. For instance in the pauli exclusion principle, the boundary of a particle is not similar to a physical object, more like a magnetic field, these oppositional forces displace other particles, producing the distant nothing in between. The smallest aspect of the universe isn’t a particle, it is potential, and a particle is a discrete localization of the stably bound particle’s potential. And nothing is all that will fit in between!