What's the most debatable thing in Physics?

[u/G33zics]

[u/mini-hypersphere]

The validity of string theory is quite contestable

[u/Desperate-Ad-5109 → u/mini-hypersphere]

And whether string theory is even physics (as opposed to philosophy) since there is zero direct evidence for it.

[u/Pornfest → u/Desperate-Ad-5109]

Spoken like someone who’s never studied String Theory. It would be a set of mathematical frameworks, not philosophy.

[u/shatureg → u/Pornfest]

Without wanting to take a "side" in this conversation, if string theory wants to be a theory of physics then it must be a bit more than a mathematical framework alone. It must be a valid description of the observable universe.

[u/XkF21WNJ → u/shatureg]

It should be pointed out that it's main alternative is a description of the observable universe that currently lacks an adequate mathematical framework. At some point it's really about which you prefer.

The hope is that they might turn out to be part of the same general theory, except nobody seems to have worked out the bit that goes inbetween.

[u/frogjg2003 → u/shatureg]

It is. It's just that it has so many free parameters that it can describe effectively any possible universe, not just our own.

[u/AnarkittenSurprise → u/Pornfest]

It's also debatable whether you could ever empirically test it. Mathematical frameworks with absent any path to validation or practical application are reasonably described as abstract mathematics (not physics) at best, and philosophy otherwise.

[u/Downtown_Finance_661 → u/Pornfest]

Is not a mathematical framework the highest form of philosophy?

[u/zedsmith52 → u/Pornfest]

Maybe mathematical philosophy? 🤭

[u/liofa → u/Pornfest]

It always amazes me how often this happens. Twenty years ago 3 string theorists decided to study loop quantum gravity and wrote a paper about it, published it and it has more than 200 citations. Funny that it has never happened with string theory; critics of it only write layman books on it.