A chat about Einstein, quantum physics and unification.

[Gmetric]

This is a 2hr chat between Sir Roger Penrose and Eric Weinstein about the formalisation of Einstein, Spinors, Twistor Theory, a whole bunch more and the potential for a unified theory via a geometric framework. I think Eric does a great job of engaging with Roger in this video resulting in a lovely discussion of the complexities and nuances of the physics relating to the geometric nature of space-time; there is one caveat, which is that Weinstein is intellectually motivated to move the discussion towards his own biases, although not heavily so. Nevertheless, it's a friendly and illuminating discussion.

[Lady Fraktor]

This looks like it should be good. Thank you.

[SkyHiker]

I listened to the whole thing -the benefit of retirement! They are both very captivating speakers.

I was reading Kerr's historical overview paper "On the discovery of the Kerr metric" not too long ago - well just browsing through it to be honest, then deciding that I could not understand it - but he was referring to spinors many times, also pointing out where they went wrong where his tetrad-based method worked. After Kerr derived his metric, the second and essentially last major EFE solution AFAIK, others came along by taking the geometry to the complex plane for a much easier derivation. An approach that Penrose also championed as he mentioned in this talk. Interesting hearing him talk about Dirac, Minkowski and Sciama.

Clearly there is no lack of mathematics to model various parts of physics in more general forms than the original version. So far it does not seem like it led anywhere in terms of a grand unified theory though. Sometimes it gets so remote from physical reality that there is no accountability anymore because they go off into areas that are physically untestable, as Weinstein alluded to.

[helicon]

Really cool - thanks Arry