[Qw3r7]

"We find that falling bodies in gravity are subject to random fluctuations (“noise”) whose characteristics depend on the quantum state of the gravitational field. "

So I read this, and I have not touched up on physics in awhile, but can someone explain to me the difference between their postulozation and the lumeniferous aether?

[whatshisface]

Although aether and fields share a couple similarities, that they're both conceptualized as filling space, and both are wave media, they have a big difference, which is that fields behave the same no matter how fast you are going, whereas aether is like air or water in that you move "though" it. Removing the concept of through-moving from space was one of the big changes that relativity made to scientific thinking.

The big consequence of through-moving was that if you send out a wave, and then move through its medium in the direction of the emission, you will "chase after" the wave front and it will escape from you more slowly than if you sat still after sending it. It turns out that this does not happen in real life when the waves involved are light or gravity. Instead, they escape you just as quickly no matter how fast you chase after them.

This was discovered in the Michelson-Morley experiment where an attempt was made to detect the motion of the earth through the universe but instead no evidence of moving through the medium that bore light was found.

Edit: By the way, I think the downvotes the parent comment received are completely unfair, they are asking for an explanation, not claiming there are no differences.

[jerf]

To put it another way, with aether, the zeroth derivative of position may be relative ("above me" may be "below you"), but the first derivative (in principle) had a universally agreeable absolute value as the velocity of something against the universal aether.

In current physics, it is only the second derivative that is absolute. We can universally agree how much acceleration something is undergoing, but neither position nor velocity have a method for absolutely measuring them.

This can be a difficult distinction to express in English but with this math terminology it should be clear how very significant the difference is.

[kkylin]

Wilczek himself has been writing / speaking about ether. A couple things I could dig up on short notice: - https://www.quantamagazine.org/why-feynman-diagrams-are-so-i... - https://news.asu.edu/20170208-finding-nothing-conversation-f... I'm sure there's more, including in Wilczek's book.

[kkylin]

Addendum: I was looking for this short article from Physics Today (https://physicstoday.scitation.org/doi/10.1063/1.882562) but page 2 is behind a paywall. Then there's the book (https://www.amazon.com/Lightness-Being-Ether-Unification-For...) which appears to expand on the theme (I've not read it).

[bradrn]

I’m not sure I see any similarities. Could you elaborate on why you think this is similar to the aether theory?

[OGMcOW2]

My very superficial understanding is that the aether was a fictional - fluid and solid - physical medium that was supposed to model behavior but created more problems.

Quantum fields are mathematical representations that model physical behavior (including the probabilities inherent in quantum mechanics).

Aether, in my interpretation, was a "thing", and quantum fields are just values that describe properties of things.

Depending on how crazy you wanna go, that does of course also make them things, and you could also look at the aether as a mathematical abstraction, but afaik, quantum fields work ridiculously well and are a solid theory, while aether - despite maybe being cutting edge at its time - is more one of the homeopathies of physics.

That said, I'm sure if looked over by someone who actually studied QT/QM/QFT/GR/SR, they'd find what I wrote to be comically primitive and inaccurate :)

edit: punctuation