But the new century brought a rough patch. Yes, there have been some remarkable findings, including the 2012 discovery of the Higgs Boson and the discovery of gravitational waves four years later. But those triumphs were based on theories developed decades earlier — a full century earlier in the case of gravitational waves. And new ideas like string theory (which holds that matter is made up of tiny vibrating loops of energy) remain unverified. “All of the theoretical work that’s been done since the 1970s has not produced a single successful prediction,” says Neil Turok, director of the Perimeter Institute for Theoretical Physics in Waterloo, Canada. “That’s a very shocking state of affairs.”
The “shocking” state of affairs is that string theory is hailed in serious publications as the best bet.
And if string theory so far has resisted experimental verification, the so-called multiverse — the idea that our universe is but one of many and perhaps an infinite number of universes — seems to some scientists more like science fiction than a description of reality.
Actually, it turns science into science fiction because it is evidence-free cosmology, like Star Wars.
Hossenfelder gets how serious the problem is:
“I can’t believe what this once-venerable profession has become,” she writes. “Theoretical physicists used to explain what was observed. Now they try to explain why they can’t explain what was not observed. And they’re not even good at that.” More.
See also: How string theory can be a theory of everything
Astrophysicist as advice columnist: Question, should I study string theory? (Sabine Hossenfelder)
Post-modern physics: String theory gets over the need for evidence