Did they finally unite quantum mechanics and general relativity?

[Airbrush]

"In a cutting-edge development, that has sent shockwaves through the scientific community, researchers at University College London (UCL) have unveiled a radical theory that seeks to reconcile two pillars of modern physics – quantum mechanics and Einstein's general theory of relativity."

Most of this is beyond me, but does anyone think this is a "cutting-edge development"?

https://www.msn.com/en-us/news/technology/revolutionary-new-theory-finally-unites-quantum-mechanics-and-einstein-s-theory-of-general-relativity/ar-AA1sKLme?ocid=msedgdhp&pc=U531&cvid=8f705b996d7b40b5b2e77ece1cfecc61&ei=35#

[Mordred]

Ooh I really like that paper still studying it. That paper is very well thought out thanks for sharing. +1

https://journals.aps.org/prx/abstract/10.1103/PhysRevX.13.041040

Edited October 24 by Mordred

[joigus]

Yes, I've read about it. So maybe you don't have to quantise the gravitational field. People have thought of that before. It didn't work. What's new here is that the metric is stochastic, which removes the consistency problems. It's been drawing a lot of attention, let me tell you.

The theory is kind of Frankensteinish in the sense that the Liouville formulation of classical mechanics coexists with quantum dynamics of fields. It's ugly IMO, it looks pretty user-unfriendly, very heavy on the technical side, but it could be a preamble to some simplifying idea that explains why space-time, and the 'field' accompanying it are fundamentally different. The author himself concedes as much:

Quote

This leads us to the second motivation for the present work: Even if one does not regard the theory as fundamental, it provides a sandbox, or toy model, for understanding quantum gravity.

(from the paper)

Btw, a simplifying idea is what physicists call 'beauty', a term sorrily misunderstood.

Thanks for the posts. Very interesting. ++

Edited October 24 by joigus
minor correction

[Mordred]

Lol back when I was first learning particle physics I recall how ugly all the different variations and equations were. So many different takes and different treatments that I often threw my hands up in absolute despair. One example was the sheer number of different virtual particles papers most of which you never hear about nowadays. 

Modern methods with its standardization are far more elegant. So I fully relate to your comment above. +1

I have read numerous papers where it's been questioned as to whether or not there was any real need to renormalize gravity or even treat it as a quantum field so that aspect has has been around for awhile however as you described what's new is keeping it stochastic in a full well connected treatment.

For those not familiar with Sturm Liouville one of the better books/articles I've come across on it was Mathematical methods for Physicists  by Arftken 

However this article is also pretty decent.

https://jahandideh.iut.ac.ir/sites/jahandideh.iut.ac.ir/files/files_course/sturm-liouville_theory_and_its_applications.pdf

 

Edited October 24 by Mordred