Did Google prepare a time crystal or did they simulate a quantum system behaving like a time crystal?

Question

The additional question on How can time crystals be useful in qRAM design? warrants it's own question. I'm moving it here.

Answer 1

TL;DR: Google did prepare a time crystal, not simulate it.

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Without quantum computers, scientists form theories and then validate them with an experiment. They may choose to test their theories by simulating them on a classical computer, but they have to validate their theories and simulation results by going to the lab. This process doesn't change with quantum computers except that the quantum computer provides the ability to simulate theories that call for a large Hilbert space.

Many-body physics thread a fine line between "simulation" and "experiment" because the quantum computer is a many-body system. One might not be too sure if the results from this paper are a simulation or an experiment until they see that the authors said "These experiments go beyond merely simulating non-Abelian order and statistics".

Although not done on a universal quantum computer, one might think that this paper simulated spin liquids because it was done on a "Quantum simulator". This is not the case. The paper says that the spin liquids were realized experimentally.

The rule-of-thumb is that when there is condensed matter involved with a quantum computer or quantum simulator, the authors will tell you it's an experiment by saying something to the tune of "we detected the phase we were looking for". Following this rule-of-thumb, in "Many-body physics in the NISQ era: quantum programming a discrete time crystal", the authors are aware that even though Sycamore can realize universal quantum computation, it can also, in their words "naturally and immediately" realize a time crystal.