Causal Dynamical Triangulation

Now THAT is a neat phrase.

"Causal dynamical triangulation."

It is apparently a theory on the cutting edge of subatomic physics. There's a wikipedia article under that title but it doesn't really explain the matter for dense folks like me.

What I do understand, though, is that efforts continue to render Einstein's understanding of gravity consistent with quantum mechanics. This requires the quantization of gravity, something that was worked out in principle in the 1960s. BUT ... the so-called "naive" quantum gravity developed by Feynman etc. can't be the last word. Physicists are agreed it can only be an approximation. How to get the rest of the way there is the continuing subject for debate.

And THAT is here CDT comes in.

What intrigues me is that, as Sabine Hossenfelder has written, CDT requires that we treat space and time differently, "which Einstein taught us not to do."

So the idea is to keep Einstein's notion of gravity, and make it consistent with quantum mechanics, in a way that will sacrifice Einstein's notion of time? That sounds right. Let's do that. I never liked Bert's notion of time anyway. That bug looks to me like a feature.

http://xstructure.inr.ac.ru/x-bin/theme3.py?level=2&index1=-24548

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