Does Light Travel Forever or Eventually Fade Away?

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Photons from an electromagnetic source, such as a flashlight, will travel indefinitely until they are absorbed. Over extremely long periods, they will lose energy due to the expansion of the universe, resulting in longer wavelengths. This energy loss occurs over billions of years, but the photons themselves do not disappear. The discussion emphasizes the distinction between electromagnetic radiation and other forms of energy. Ultimately, while photons can travel vast distances, they are subject to energy loss over time.
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So from an electromagnetic source, will the photons travel "forever" or will some of them "collapse" after a while ?
 
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Are you talking about an electric/magnetic field (ie a magnet) or light (ie a flashlight)?
 
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'.
 
Sorry i ment Electromagnetic radiation (Radio and Light). By loosing energy do you mean that the wavelength will be longer?
 
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)
 
But remember that takes billions of years :)
 
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