Any proof of extra dimensions?

[Trollfaz]

As of 2020 is there any proof of tiny extra dimensions or observations of them?

 

[Vanadium 50]

Proof is for mathematics, not physics.

 

[jedishrfu]

@Vanadium 50 except when its experimental proof aka evidence as was implied here.

In answer to the OP, no there is no experimental proof.

In this Quora thread, Prof Richard Muller author of the book "Physics for Future Presidents" writes:

https://www.quora.com/Is-there-even-a-slightest-proof-that-multiple-dimensions-exist?share=1

No.

I assume that your question is really this: is there any indication that there is a fourth or fifth space dimension, one that may be hidden from easy detection because it is “compact”, that is, curled up.

No.

On the other hand, if you take the word “dimension” to mean the mathematical definition of dimension, then it is trivial that there are numerous other dimensions. Temperature is a dimension; so is color; so is the number of photons. But I don’t think you were referring to this meaning of the word, because if you were, the question (and answer) isn’t very interesting.

A space dimension would be one that could be transformed into one of the existing spatial dimensions through a rotation. It would be a non-reducible dimension in a vector space.

There are some experimental efforts to detect other spatial dimensions, particularly by looking for deviations in gravity at small (meter, cm, mm) dimensions. Nothing has yet given a positive result.

Do other dimensions exist? Many of my theorist friends would vote “yes”. I would vote “no”. Multiple dimensions provide a mechanism for getting rid of some of the infinities of quantum theory, but in my mind, that is a rather weak reason to believe in them. I suspect we’ll find a better way to fix the theory, some day.

 

[Lord Crc]

Proof is for mathematics, not physics.

I don't think that's a useful reply. If you really wanted to help him by correcting him, then you should at the very least provide the correct word.

In my native language proof and evidence translate to the same word, and hence easy to get wrong. And he did ask for observations, which provided extra context for what he was after.

 

[jedishrfu]

We often get language confusion on PF so there's no need to discuss it further in this context.

I'm closing this thread now with the following video for the OP that discusses why math works so well in describing reality.



and the classic book Flatlands by Abbott and this film based on it:



If you were a flatlander odd things appear to happen as a higher dimensioned object traverses through your plane of existence. You might observe the object as expanding or shrinking and you would be hardpressed to explain as to how it could do this in two dimensions and so you would be forced to introduce a new dimension as one possible explanation.

So while there is no physical direct experimental proof, there are some phenomena that are explained and so it becomes a part of your theory of everything.