Does an Electron's Field Expand at c Upon Spontaneous Creation?

  • Context: Undergrad 
  • Thread starter Thread starter idea2000
  • Start date Start date
  • Tags Tags
    Electron Field
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
5 replies · 1K views
idea2000
Messages
99
Reaction score
2
If an electron were to be spontaneously created at a point somewhere in space, would the electron's field expand outwardly at the speed of light, regardless of frame, just like how a flash of light would expand outward at the speed of light, regardless of frame?
 
Physics news on Phys.org
how about pair production or an electron ejected from a nucleus? would the field expand outward at the speed of light, regardless of the frame of reference?
 
idea2000 said:
how about pair production or an electron ejected from a nucleus? would the field expand outward at the speed of light, regardless of the frame of reference?
Yes. This would essentially be a small dipole antenna. The field from a dipole antenna is definitely known to propagate at the speed of light.
 
Last edited:
  • Like
Likes   Reactions: Ibix
Although just for to be sure... @idea2000 when you say "electron field" you mean the electromagnetic field of the two charged particles, right?
 
  • Like
Likes   Reactions: Ibix and Dale
idea2000 said:
If an electron were to be spontaneously created at a point somewhere in space, would the electron's field expand outwardly at the speed of light, regardless of frame, just like how a flash of light would expand outward at the speed of light, regardless of frame?

The best way of saying this is probably that classically, changes in the electromagnetic field in a vacuum propagate at "c". As other posters have mentioned, one cannot create charges without violating conservation laws, though one can create a dipole. The changes in the field when one creates the dipole propagate at "c", as do others sorts of changes in the electromagnetic field.

To get more detailed than these needs some math, but I'm not sure what level of math you'd be interested in and comfortable with.
 
  • Like
Likes   Reactions: dextercioby