4 ms·

Are virtual particles a real thing or just a description of the underlying system?

monocasa 5y ago
Just as real as the concepts of particles at all. They're just really likely to recombine because they form in pairs of opposite charges and will attract and annihilate. Hawking radiation is adding another force with a gradient (extremely strong gravity near an event horizon) that'll absorb one of the particles of the pair, and then the other flies off into space as the real, bona fide particle it always was.
Fordec 5y ago
Virtual particles are the universes equivalent of local variables inside a function. Parameters go in, results come out, but what stays in that local context still existed even if they didn't have global scope.
- RosanaAnaDana 5y ago
  I realize the above is analogy, but can someone more informed than me confirm the correctness of the above description, because I find it to be a particular good one.
  - cwillu 5y ago
    I can think of some analogous ways to recover some semblance of the analogy, but it's not really a great one. A virtual "particle" is really more of a "disturbance" in a field: think splashing in a pool vs a wave. And in the context of the contents of a proton, imagine trying to differentiate a well-behaved 1hz wave from the other noise in the liquid, when the liquid is in a blender. edit to add: To recover the local/global variable analogy, imagine the compiler was continuously recompling the code based, inlining (or undoing that inlining), hoisting variables out of loops (or inserting them back), and trying to determine where a particular temporary value for calculation is being stored. Again, it's not a _great_ analogy; because I have a hard time determining how understanding the analogy would lead you to correct conclusions about virtual particles, but yeah.
- amerine 5y ago
  Thank you.
tux3 5y ago
While they are real, the name is a little misleading. Virtual particles are not quite the same kind of disturbance in a field as full-blown, bona-fide, certified particles. They're two different kind of object that come out of the equations, and they happily interract or turn into each other sometimes. But Virtual Particle doesn't mean they're not real, and also doesn't mean they're particles :) Disclaimer: I'm ignorant, and this is my summary of Matt Strassler off the top of my head. Mistakes are mine. Source: https://profmattstrassler.com/2011/10/10/virtual-particles-not-particles-at-all/ https://profmattstrassler.com/2011/10/10/virtual-particles-n...
- amerine 5y ago
  Thank you.

Just as real as the concepts of particles at all. They're just really likely to recombine because they form in pairs of opposite charges and will attract and annihilate. Hawking radiation is adding another force with a gradient (extremely strong gravity near an event horizon) that'll absorb one of the particles of the pair, and then the other flies off into space as the real, bona fide particle it always was.

Fordec 5y ago

Virtual particles are the universes equivalent of local variables inside a function. Parameters go in, results come out, but what stays in that local context still existed even if they didn't have global scope.

RosanaAnaDana 5y ago
I realize the above is analogy, but can someone more informed than me confirm the correctness of the above description, because I find it to be a particular good one.
- cwillu 5y ago
  I can think of some analogous ways to recover some semblance of the analogy, but it's not really a great one. A virtual "particle" is really more of a "disturbance" in a field: think splashing in a pool vs a wave. And in the context of the contents of a proton, imagine trying to differentiate a well-behaved 1hz wave from the other noise in the liquid, when the liquid is in a blender. edit to add: To recover the local/global variable analogy, imagine the compiler was continuously recompling the code based, inlining (or undoing that inlining), hoisting variables out of loops (or inserting them back), and trying to determine where a particular temporary value for calculation is being stored. Again, it's not a _great_ analogy; because I have a hard time determining how understanding the analogy would lead you to correct conclusions about virtual particles, but yeah.
amerine 5y ago
Thank you.

tux3 5y ago

While they are real, the name is a little misleading. Virtual particles are not quite the same kind of disturbance in a field as full-blown, bona-fide, certified particles. They're two different kind of object that come out of the equations, and they happily interract or turn into each other sometimes. But Virtual Particle doesn't mean they're not real, and also doesn't mean they're particles :) Disclaimer: I'm ignorant, and this is my summary of Matt Strassler off the top of my head. Mistakes are mine. Source: https://profmattstrassler.com/2011/10/10/virtual-particles-not-particles-at-all/ https://profmattstrassler.com/2011/10/10/virtual-particles-n...

amerine 5y ago
Thank you.