Only in universe with 5 dimensions. Shouldn't string theory be given up on at this point? This theory has existed for over 50 years and hasn't produced any results. Even the predictions made by it such as e.g. supersymmetry have not been confirmed despite searching for them at particle colliders.

  Shouldn't string theory be given up on at this point? 

I foolishly sat in 8.821 [0] while at MIT thinking I could make sense out of quantum gravity. Most of the math went over my head, but the way I understand this paper, it’s basically a cosmic engineering fix for a geometry problem. Please correct me if necessary.

String theory usually prefers universes that want to crunch inwards (Anti-de Sitter space). Our universe, however, is accelerating outwards (Dark Energy).

To fix this, the authors are essentially creating a force balance. They have magnetic flux pushing the universe's extra dimensions outward (like inflating a tire), and they use the Casimir effect (quantum vacuum pressure) to pull them back inward.

When you balance those two opposing pressures, you get a stable system with a tiny bit of leftover energy. That "leftover" is the Dark Energy we observe.

You start with 11 dimensions (M-theory) and roll up 6 of them to get this 5D model. It sounds abstract, but for my engineer brain, it's helpful to think of that extra 5th dimension not as a "place" you can visit, but as a hidden control loop. The forces fighting it out inside that 5th dimension are what generate the energy potential we perceive as Dark Energy in our 4D world. The authors stop at 5D here, but getting that control loop stable is the hardest part

The big observatiom here is that this balance isn't static -- it suggests Dark Energy gets weaker over time ("quintessence"). If the recent DESI data holds up, this specific string theory solution might actually fit the observational curve better than the standard model.

[0] https://ocw.mit.edu/courses/8-821-string-theory-and-holograp...

Hm, string theory can describe a lot of things, but it's not testable with current technology. I'm pretty sure that other mathematical constructs exist that could also describe a similar set of properties, but we just happened to stumble upon string theory first, and got enamored with some of the nice properties it had initially.

They had to keep the theory alive somehow.

Sounds like overfitting.

The prediction is just 105 orders of magnitude (and an extra dimension) away, but ok.

I don't know who wrote the title for this submission, but adding a question mark that is not in the linked article seems like a terrible editorial decision.

Yes. Like Python can describe any turing machine.