5 ms·
And also https://profmattstrassler.com/articles-and-posts/particle-physics-basics/virtual-particles-what-are-they/ https://profmattstrassler.com/articles-and-po
by cwillu 4y ago
And also https://profmattstrassler.com/articles-and-posts/particle-physics-basics/virtual-particles-what-are-they/ https://profmattstrassler.com/articles-and-posts/particle-ph...
“A virtual particle is not a particle at all. It refers precisely to a disturbance in a field that is not a particle.”
- nimish 4y agoAlso virtual particles don't make sense in a non-perturbative regime like room-temp protons, since they are an aid to understanding terms in the perturbation series expansion. Not sure how they even apply in the case where Feynman diagrams aren't applicable. Hell, the calculations likely use lattice QCD which eschews them entirely!
- zakk 4y agoProtons are non-perturbative, indeed, but this does not mean that there are no virtual particles exchanged inside a proton. It seems like your comment implies that, sorry if I misunderstood. On the contrary, this means that there are too many virtual particles (gluons) being exchanged inside a proton, so many that perturbation theory is not applicable.
- AnimalMuppet 4y agoAre gluons virtual? (Or are they virtual inside a proton?)
- frutiger 4y agoGluons are real.
- blueprint 4y agoVirtual particles are also "real", and if you don't believe me, at least you have to admit that virtual photons alone lead to real energy (e.g. Casimir effect) - and it has also been stated that gluons within protons can be interpreted as "virtual"... so I'm pretty sure your comment is wrong. I'd downvote you if I could since that seems to be what the cool kids here are doing but I used up all my karma telling the truth.
- hilbert42 4y ago"Virtual particles are also "real"." No doubt, and Casimir is probably sufficient evidence, but it seems to me a lot of confusion would be saved if we changed the name. To what I don't know - perhaps something like say quantum energy disturbance but more eloquent or descriptive.
- blueprint 4y ago100%. "Possible" particle? :)
- cwillu 4y agoYour question is can be posed as “is there a well-behaved resonance of the gluon field in a proton, that lasts long enough for it to be identified”. It's kinda like identifying a bubble in a pot of cold water vs a pot just starting to boil vs a rolling boil.
- hither_shores 4y agoVirtual particles are part of an indexing scheme for perturbation series - saying that you leave the perturbative regime when you have "too many" of them is like saying that crystalline solids melt when they have too many normal modes.
- xigency 4y agoFinally an analogy where I understand neither comparison :)
- est 4y agothis is the most important TIL article I've read in years. Thanks! Basically, it's like a playing around virtual machine on a physical PC.
- Kranar 4y agoThere are also tons of articles that state the opposite; that virtual particles are in fact actual particles. I don't see how either interpretation is particularly relevant. Physics uses math to model reality. Every part of that model is virtual and has some correspondence with what we experience and observe and that's all that matters at the end of the day.
- cwillu 4y agoThe physical dress is blue and black, in spite of all the articles showing how to see it as white and gold, the articles demonstrating how in theory you could have a white and gold dress look like that given the correct lighting, and the articles saying that the distinction isn't real and that all black and blue dresses are equivalent to white and gold dresses.
- est 4y ago> that virtual particles are in fact actual particles I assume that means those "virtual particles" behave almost like actual particles. e.g. have a rest mass or not. This helps lay person understand physics better.
- hilbert42 4y agoDepends on the definition of a particle, and 'virtual particles' aren't the same as 'real' particles. As I said above it'd be a good idea to change the name, it'd stop lots of confusion.