The multiverse makes physics so cool that it is indistinguishable from self-indulgence.
Sheldon: “By measuring a hot stream of molecules with billions of states, this experiment may rule out CSL [Continuous Spontaneous Localization]. If so, it would be the first time an interpretation of QM was actually invalidated, suggesting we have entered a new era of testing theories of the foundations of QM.”
Baggott, of course, also feels the need to take the ritual swipe at ID. He must do so because he is allowed to criticize crackpot cosmology provided that he holds to no thesis about the nature of nature that would impede its actual advance. He can regret it but he must not undermine it.
Hossenfelder: In the many worlds interpretation, if you set up a detector for a measurement, then the detector will also split into several universes.
His universe is deterministic, presumably, because everything happens. End of story. Actually, end of all stories.
Carroll: “The price we pay for such a powerful and simple unification of quantum dynamics is a large number of separate worlds.” Right. And the price you pay for suicide is that nothing you do in this world afterward matters.
Carroll wants a multiverse out of any new findings, one suspects. One question many might have is, apart from the lack of a multiverse, how bad is the current situation in physics? What, besides that, is going wrong?
Crease writes as if he would very much like to buy into Carroll’s ideas but still thinks that sanity has something to offer. Possibly, many establishment science figures teeter on that brink.
Ethan Siegel: Even the most successful scientific theories imaginable will, by their very nature, have a limited range of validity. But we can theorize whatever we like, and when a new theory meets the following three criteria…
Of course she’s right about the religion part. Much that is going wrong with science today is the tendency to use various science ideas as secular religions. The multiverse happens to be a particularly devastating one because it strikes at the very idea of evidence.
Actually, multiverse cosmology would make a starting point irrelevant or else subject to endless redefinition. Powell’s bookmark-able summary can’t address the problem, of course, but that’s precisely what the multiverse does. Facts no longer matter much because contradictory facts have equal status.
In an infinite universe, somebody somewhere has figured out how to talk from one universe to another. In an infinite universe, somebody somewhere has figured out how to talk from one universe to another.
For example, how can we “partition an infinite multiverse so to arrive at the finite probabilities we observe and require (e.g. for quantum mechanics) because in an infinite multiverse everything that can happen happens an infinite (with the same cardinality) number of times?”
With respect to the simulation multiverse: Why could there not be countless, helplessly infinite, simulations of the simulations as well?
But wait! There might be an infinity of multiverses in which you are not unique. This is the only one in which your head has not exploded.