> There are no lessons to be learned about quantum gravity here. There are no lessons to be learned about traversable wormholes or whether they exist within our Universe. There are not even any lessons to be learned about the uniqueness or capabilities of quantum computers, as everything that was done on the quantum computer can be done and had previously (without errors!) been done on a classical computer. The best that one can take away is that the researchers, after performing elaborate calculations of the Sachdev-Ye-Kitaev model through classical means, were able to perform an analogous calculation on a quantum computer that actually returned signal, not simply quantum noise
They simulated a toy space-time model, which had been previously simulated on a classical computer, on a quantum computer. That's really it.
The toy model has wormholes.
That does not inform us as to if the real universe has wormholes.
The novel thing is really how they used ML to boil down the mathematical model into something that could run on a quantum computer.
Yapping about how they "created wormholes in a lab" is 100% a publicity stunt. They could have written instead that they simulated wormholes in a lab, which would have been more honest and they should have pointed out that anyone can simulate a wormhole on their desktop computer as well.
And not even. A toy model in a space-time that is wildly different from our real space. Their space is AdS, i.e. negative curvature, vs. our dS space with positive curvature. Their toy space has a toy model of gravity, that is way different from our real gravity. And their space is 1-dimensional.
And they didn't even simulate that. They used the AdS/CFT conjecture to tell them, that they don't need to simulate the toy model in the toy space, but they can simulate a lower-dimensional holographic image of the toy space. A 0-d hologram of a 1-d space. Whatever that is.
It's even less than that. The duality between SYK_4 (SYK with four-fermion interactions) and AdS_2 (2D AdS spacetime) is only (conjectured to be) true at infinite N (where N is the number of fermions) and at the conformal limit (ie. the limit where temperature goes to zero). What they did is a N=7 simulation of a (sparse SYK) Hamiltonian "learned" (a much better word would have been "fitted") from a N=10 dense SYK at various (finite) temperatures. Neither 7 nor 10 is large enough to test this limit.
Now the actual quantum simulation they performed is that they constructed a thermal field double (and this allows them to make the connection with a "wormhole" because the two side of the TFD are basically the left and right quadrant of the Penrose diagram) and evolved it with the "learned" sparse SYK plus some shockwave operator $e^{i\mu V}$. The actual construction of the quantum gates is due to that Jafferis-Gao wormhole teleportaion paper. The supplementary material has some useful information (I find the actual Nature paper to be quite thin on technical details). It is indeed an interesting quantum simulation, in the sense that it demonstrated that the Google quantum computer behaves the way one expects a QC to behave.
Now does this experiment actually tell us anything about quantum gravity? No, and in this sense it is a publicity stunt. My reading of the Nature paper is that the actual paper is about 20% science (mostly due to Google's hardware) and about 80% salesmanship, which is really what you need in order to survive in academia.
> our dS space
To clarify this, our universe is asymptotically a dS spacetime in the distant future where matter and radiation density become zero and the universe becomes dominated by vacuum energy (and this is necessarily a conjecture based on current theory and cosmological observations, because nobody can live this long to see that day). It's not literally a dS spacetime right now.
> There are no lessons to be learned about quantum gravity here. There are no lessons to be learned about traversable wormholes or whether they exist within our Universe. There are not even any lessons to be learned about the uniqueness or capabilities of quantum computers, as everything that was done on the quantum computer can be done and had previously (without errors!) been done on a classical computer. The best that one can take away is that the researchers, after performing elaborate calculations of the Sachdev-Ye-Kitaev model through classical means, were able to perform an analogous calculation on a quantum computer that actually returned signal, not simply quantum noise
They simulated a toy space-time model, which had been previously simulated on a classical computer, on a quantum computer. That's really it.
The toy model has wormholes.
That does not inform us as to if the real universe has wormholes.
The novel thing is really how they used ML to boil down the mathematical model into something that could run on a quantum computer.
Yapping about how they "created wormholes in a lab" is 100% a publicity stunt. They could have written instead that they simulated wormholes in a lab, which would have been more honest and they should have pointed out that anyone can simulate a wormhole on their desktop computer as well.