When a photon is created, it instantly achieves the speed of light -- How?

[zuz]

I've been told that when a photon of light is created it instantly achieves the speed of light without having to 'speed up". How is this possible?

 

[James Chase Geary]

Pedantically, photons are just light, so whatever speed they go is the speed of light.

To answer the question you are asking, however, the photons are emitted with a certain amount of energy. The process which goes into the photon being created requires the energy that makes it go as fast as it does.

 

[ZapperZ]

I've been told that when a photon of light is created it instantly achieves the speed of light without having to 'speed up". How is this possible?

When you drop a pebble onto the surface of water, do you notice the ripple being created speeding up, or do you see it immediately moving at the a particular speed?

There is also no "why" or "how" in this case, the same way we do not have the why's and how's for light having a fix, constant speed in vacuum.

Pedantically, photons are just light, so whatever speed they go is the speed of light.

To answer the question you are asking, however, the photons are emitted with a certain amount of energy. The process which goes into the photon being created requires the energy that makes it go as fast as it does.

This is false, or misleading at best. It somehow implies that its speed depends on its energy, which is wrong. There is nothing to indicate light having a lower energy limit to make it go at c. All light, no matter how low its energy, moves at c.

Zz.

 

[phinds]

I've been told that when a photon of light is created it instantly achieves the speed of light without having to 'speed up". How is this possible?

Just to add to what others have said, emitted light is not a photon, it's a wave. That is, there are no photons in a beam of light. The wave only creates a photon when it interacts with something. This is important because a lot of people, I think possibly including you, think that the emitted "photon" is like a little tiny billiard ball that goes shooting off at the speed of light.

 

[James Chase Geary]

My apologies for my lack of rigor. I wasn't trying to be misleading, just trying to get at the concept in an intuitive way. But yes, of course, the speed doesn't depend on the energy. I just meant to imply that photons were created by a some kind of process already moving at light speed.

 

[davenn]

I just meant to imply that photons were created by a some kind of process already moving at light speed.

which also is not good
what do/did you think was already moving at c ?