Does Light Have an Endless Journey? Exploring the Lifespan of Photons

In summary, photons emitted from an electromagnetic source such as a flashlight will travel forever until they get absorbed. They may also lose energy over extremely long periods of time due to the expansion of the universe, but they will never disappear. This phenomenon can also be observed in electromagnetic radiation, such as radio and light, where the wavelength may become longer as the energy decreases. However, this process takes billions of years to occur.
  • #1
jsa0100
4
0
So from an electromagnetic source, will the photons travel "forever" or will some of them "collapse" after a while ?
 
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  • #2
Are you talking about an electric/magnetic field (ie a magnet) or light (ie a flashlight)?
 
  • #3
I'm going to assume you mean a flashlight.
In that case the photons will travel forever until they get absorbed.

They will also lose energy over extremely long periods of time due to the expansion of the universe, but will never 'dissapear'.
 
  • #4
Sorry i ment Electromagnetic radiation (Radio and Light). By loosing energy do you mean that the wavelength will be longer?
 
  • #5
jsa0100 said:
Sorry i ment Electromagnetic radiation (Radio and Light). By loosing energy do you mean that the wavelength will be longer?

Yes

(adding text because my post was too short)
 
  • #6
But remember that takes billions of years :)
 

1. Does light travel forever?

Yes, in a vacuum, light travels forever. This is because light does not experience friction or resistance, so it can continue to travel indefinitely.

2. Is there a limit to how far light can travel?

There is no known limit to how far light can travel. However, the further light travels, the more it can be affected by factors such as gravitational pull and cosmic expansion.

3. How fast does light travel?

In a vacuum, light travels at a constant speed of approximately 299,792,458 meters per second, which is equivalent to 670,616,629 miles per hour.

4. Can light be slowed down or speed up?

Light can be slowed down by passing through certain materials, such as water or glass. However, it cannot be sped up beyond its maximum speed in a vacuum.

5. Will light ever stop traveling?

As long as there is no obstruction or absorption, light will continue to travel indefinitely. However, it can be redirected or absorbed by objects in its path, causing it to stop or change direction.

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