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Study reveals substantial evidence of holographic universe

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Re: Study reveals substantial evidence of holographic universe

#151

Post by bsaul »

marcosdumay wrote: post #54
PaulAJ wrote: post #29

Earlier quoted context omitted.

I'm familiar with the idea of coordinate transforms and projections, so I get the idea that you could project our 3D universe onto a 2D surface, and I kind of see how a hologram encodes 3D information, but I don't see how that is a useful idea. Or are there only certain kinds of 4D information that can be encoded in the 2D surface, so our 4D model of space and time gets reduced to a theory of only 2 dimensions? Are t…

Laymen "easy" language makes everything harder to understand. The holographic principle means that if you take a sphere somewhere, the amount of entropy you can push there grows with r^2, and not with r^3 like you'd expect.

Thanks a lot. I've just watched susskind talk on the universe as a hologram ( https://youtu.be/2DIl3Hfh9tY ), and it didn't occured to me until i read what you just said simply that the holographic principle meant you could actually push less stuff / bits in a black hole by growing it, than you first thought if you compared it to a volume growing. So that meant information was stored on its surface (r^2), and not inside it (r^3).

Am i correct ?

Re: Study reveals substantial evidence of holographic universe

#152

Post by Florin_Andrei »

sandworm101 wrote: post #150
Florin_Andrei wrote: post #61

Earlier quoted context omitted.

Distances are "illusory" to some extent anyway. On a large scale, relativity makes both time and space dependent somewhat on other factors. On a small scale, quantum mechanics similarly de-absolutizes position (space) and momentum. Space and time as absolutes appear to be a construct, a consequence of us being highly complex neural networks trained at a specific scale of the Universe - the "human scale" - as beings a…

Up or down several dozen orders of magnitude. Time and space exist for the cells in our bodies, and for mountains, moons and most stars. Time and space only break down substantially for things smaller than molicules or large enough to twist spacetime back in itself (black holes). A mouse is no further away from the moon than a dog or elephant.

> Up or down several dozen orders of magnitude.

I agree.

Re: Study reveals substantial evidence of holographic universe

#154

Post by ZeroFries »

mikekchar wrote: post #132
Groxx wrote: post #110

Earlier quoted context omitted.

So is holographic universe theory expected to work without qualification (thus being indistinguishable), or is it more of a temporary patch that nobody believes is correct, but works better for one area, and worse for others? Newton's model of gravity works well enough for approximation at human scales, but is flawed enough that you don't use it for astrophysics or microscopic realms.

No model accurately represents reality. I think people have this idea that if I have 2 different theories that predict exactly the same thing, that one of them is right and another is wrong. This is exacerbated by a misunderstanding with Occam's razor. It is popular to believe that given those 2 theories, the simpler one is correct. This is not necessarily the case. The simpler one is simpler and therefore a better m…

Well said. Models do not contain reality: reality contains models. Do not confuse the map with the territory, and all you have are maps.

Re: Study reveals substantial evidence of holographic universe

#155

Post by flaviojuvenal »

blincoln wrote: post #51

Possibly dumb question, but I know my niece is going to ask me about this, and I'd like to be able to give her a solid response: does this mean that most distances within our universe are illusory? If not, why not? To expand on that thought a little bit, with a hologram, the projected object is an illusion, and can be made to appear to move at arbitrary speed by e.g. rotating the projection apparatus. On a larger sca…

IANAPhysicist, but I think T-duality in String Theory [1] also makes distances "illusory".

"If string theory is a correct theory of Nature, then this implies that on some deep level, the separation between large vs. small distance scales in physics is not a fixed separation but a fluid one, dependent upon the type of probe we use to measure distance, and how we count the states of the probe." [2]

Brian Greene also explains why in an accessible way in the Chapter 10 of The Elegant Universe [3], which I recommend.

[1] https://en.wikipedia.org/wiki/T-duality

[2] http://www.superstringtheory.com/basics/basic6a.html

[3] https://en.wikipedia.org/wiki/The_Elegant_Universe

Re: Study reveals substantial evidence of holographic universe

#156

Post by ZeroFries »

_0w8t wrote: post #114
wturner wrote: post #86

Earlier quoted context omitted.

This is the perspective that I hardly ever hear discussed when the issue of "human freedom" is brought up. If you assume we are a result of the big bang, then the causal relationship infers humans are not free. If on the other hand you assume humans "are" the universe, then an entirely different perspective seems to be possible albeit one that is much more confusing to reason about.

Freedom of will is completely compatible with fully deterministic world. Just consider that there are many fully deterministic worlds but the one one perceives themselves in depends on freedom of choice.

Who chooses the world to perceive? How is the choice made?

Re: Study reveals substantial evidence of holographic universe

#157

Post by JBlue42 »

blincoln wrote: post #51

Possibly dumb question, but I know my niece is going to ask me about this, and I'd like to be able to give her a solid response: does this mean that most distances within our universe are illusory? If not, why not? To expand on that thought a little bit, with a hologram, the projected object is an illusion, and can be made to appear to move at arbitrary speed by e.g. rotating the projection apparatus. On a larger sca…

I have nothing to add other than I think it's awesome your niece might ask you about this.

Re: Study reveals substantial evidence of holographic universe

#158

Post by omio »

ge96 wrote: post #141
hooph00p wrote: post #115

Earlier quoted context omitted.

and here I was trying to avoid an existential crisis today. There that goes.

Could be a dimensional thing too, what if you're like an exhibit in someone's living room like a hologram and you just live your life for someone's amusement. You'd never know but can you prove that it's happening?

Reminds me of The Thirteenth Floor.

Re: Study reveals substantial evidence of holographic universe

#159

Post by mikekchar »

Groxx wrote: post #140
mikekchar wrote: post #132

Earlier quoted context omitted.

No model accurately represents reality. I think people have this idea that if I have 2 different theories that predict exactly the same thing, that one of them is right and another is wrong. This is exacerbated by a misunderstanding with Occam's razor. It is popular to believe that given those 2 theories, the simpler one is correct. This is not necessarily the case. The simpler one is simpler and therefore a better m…

Which is why I grabbed Newton's gravity model as an example. It's known to be a flawed model, only useful as a simplified approximation method that's "good enough" for many purposes. It's like having a model that says "quack-like sound == duck". It's wrong. We know it's wrong. It may be useful when looking at birds, but it's 100% wrong when your hard drive produces the noise. Of course it's a spectrum, but some of th…

We could, one day, wake up to discover that we are actually living in the matrix. The rules of physics were only added by the machines to keep us amused so that we don't discover the true nature of our beings (batteries for the machines). Yeah... I don't believe it either :-)

But the key is that we can't know. Maybe "God did it" is the truth and the rest is just appearances. Maybe our mathematical constructs do represent reality closely. Even if we build models that are isomorphic to our perception of reality, there is still no way to tell if they are in any way similar to the actual workings of reality. The FSM can certainly alter our brains so that we just believe we see things happening in a consistent way, even though they are not.

Like I said, it is tempting to believe that the simplest solution that we can imagine is close to reality. This is very unlikely to be the case, IMHO. It's fine to believe it is, but that is not science any more. You are entering into religion.

Newton's laws are not known to be "more wrong" than relativity. Relativity matches our observations more closely and is simpler in some respects, but it could be just as wrong. Or more wrong. We have no way of measuring how close to reality our models are. We can only measure how closely they match our observations. As one of the other posters quoted: All models are wrong. Some of the are useful.

Even when you have a model that is completely consistent with observations it does not make it more likely to be correct. Imagine creating some byzantine model with a myriad of exceptions to explain away any discrepancy. Obviously as long as we accept complexity, we can model anything. These models are not usually useful though.

So as much as I understand that you want to ask, "Is this model more likely to be closer to the truth than other models", it isn't a question we can answer in science. We can only answer the questions, "Is this model consistent with our observations?", and "Is this model simpler than another model?"

The article claims that the model is at least as consistent as other models while being simpler in some instances. I think work needs to be done to verify those claims.

Re: Study reveals substantial evidence of holographic universe

#160

Post by droopybuns »

I cant tell if all of the comments here are genuine, or the output of some high performance markov chains.

Also, i have absolutely no ability to penetrate what is being described by this article. Holograms work by applying lasers to different surfaces and re-rendering the image relative to the original laser's point of view. How does the word 'holographic' apply?

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