So a massless particle cannot be stationary?DaleSpam said:Hi TheDarkness, welcome to PF
The only speed that a massless particle can travel at is c.
Yes, but when an electron jumps to a lower shell, and emits a photon, would not the acceleration of the photon from the point of creation be infinite?DaleSpam said:Correct, it can only move at c never more and never less.
Any real photon is on-shell, meaning that it travels at c at all times. If it traveled at less than c then it would be off shell and could not conserve both energy and momentum.TheDarkness said:Yes, but when an electron jumps to a lower shell, and emits a photon, would not the acceleration of the photon from the point of creation be infinite?
I see. Thank you.DaleSpam said:Any real photon is on-shell, meaning that it travels at c at all times. If it traveled at less than c then it would be off shell and could not conserve both energy and momentum.
What of virtual particles?DaleSpam said:Any real photon is on-shell, meaning that it travels at c at all times. If it traveled at less than c then it would be off shell and could not conserve both energy and momentum.
Virtual particles are off shell, by definition, so all bets are off. Virtual photons can have mass, travel at speeds other than c, and so forth.TheDarkness said:What of virtual particles?
Spontaneous velocity refers to the instantaneous rate of change of the position of an object without any external force acting on it. It is also known as constant velocity or uniform motion.
Spontaneous velocity is calculated by dividing the change in position (displacement) by the change in time. The formula for spontaneous velocity is v = Δx/Δt.
A=∞/-∞ is a mathematical representation of infinite acceleration, which is when the velocity of an object is changing at an infinitely fast rate. This can occur at the moment an object experiences spontaneous velocity.
No, an object cannot maintain a spontaneous velocity indefinitely. In order for an object to maintain a constant velocity, there must be no external forces acting on it. However, in the real world, external forces such as air resistance and friction will eventually cause the object to slow down and come to a stop.
Spontaneous velocity and constant velocity are essentially the same thing. However, spontaneous velocity is a more specific term that implies there is no external force acting on the object, while constant velocity can refer to any type of motion where the speed and direction remain constant over time.