Moderators: Calilasseia, ADParker
Steve wrote:I am not a mathematician, but does this have the potential to advance the language of physics sort of like calculus in Newtons day? That would be very cool. No hot. I said I wasn't a mathematician, right?
Rumraket wrote:Steve wrote:I am not a mathematician, but does this have the potential to advance the language of physics sort of like calculus in Newtons day? That would be very cool. No hot. I said I wasn't a mathematician, right?
And relatedly, will this help with significantly reducing the computational cost of simulating fundamental physics by simplifying the mathematics required to model it?
iamthereforeithink wrote:Yoohoo! I would advise the OP to change his username to "amplituhedron59". We don't need 'em twistors anymore.
Physicists have discovered a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality.
“This is completely new and very much simpler than anything that has been done before,” said Andrew Hodges, a mathematical physicist at Oxford University who has been following the work.
The revelation that particle interactions, the most basic events in nature, may be consequences of geometry significantly advances a decades-long effort to reformulate quantum field theory, the body of laws describing elementary particles and their interactions. Interactions that were previously calculated with mathematical formulas thousands of terms long can now be described by computing the volume of the corresponding jewel-like “amplituhedron,” which yields an equivalent one-term expression.
“The degree of efficiency is mind-boggling,” said Jacob Bourjaily, a theoretical physicist at Harvard University and one of the researchers who developed the new idea. “You can easily do, on paper, computations that were infeasible even with a computer before.” Continued...
advaitya wrote:I read the article. On the one hand, it gives the impression that the researchers have simply landed upon a more efficient method of doing certain calculations.
But the article also quotes the researchers speculating that space and time might not be fundamental features of the universe. Where would it leave gravity, which in GR is an effect of spacetime? Does gravity become something non-fundamental, or emergent as well?
iamthereforeithink wrote:To me, it makes sense that space and time are emergent, rather than fundamental. It saves us from having to answer questions like "When did time begin?".
twistor59 wrote:iamthereforeithink wrote:To me, it makes sense that space and time are emergent, rather than fundamental. It saves us from having to answer questions like "When did time begin?".
As far as I know (i.e. not very far!), in these holographic boundary theories, to date it's only spatial dimensions which they've been able to make emerge, not temporal ones.
iamthereforeithink wrote:twistor59 wrote:iamthereforeithink wrote:To me, it makes sense that space and time are emergent, rather than fundamental. It saves us from having to answer questions like "When did time begin?".
As far as I know (i.e. not very far!), in these holographic boundary theories, to date it's only spatial dimensions which they've been able to make emerge, not temporal ones.
Yes (AFAIK), but time seems to be entirely absent from these models. I'm not sure what that means.
iamthereforeithink wrote:
I'm also not completely clear about the implications of this particular geometric object. Apparently, it also does away with the need for virtual particles and "unitarity". How does it do that? When they say it does away with unitarity, do they mean that the probabilities don't sum up to one, or that probabilities are not needed at all?
DavidMcC wrote:I'm not sure that the "jewel-like geometric object" means that space-time is somehow unnecessary for the particles to exist in, and interact. I suppose it depends on your cosmology. In mine, particles are but excitations of space in the first place, so the latter would still be necessary.
Users viewing this topic: No registered users and 1 guest