Define Red-Shift: Explaining BH Event Horizon

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Redshift in the context of a black hole's event horizon (EH) is primarily explained by the Doppler Effect and time dilation. Observers in stronger gravitational fields appear to experience time more slowly compared to those in weaker fields. As an observer approaches the event horizon, they appear to slow down and never fully cross it from an outside perspective. Consequently, any light waves emitted by the observer become redshifted, showing longer wavelengths due to this time dilation effect. This phenomenon highlights the complex relationship between gravity, time, and light near black holes.
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Could some one explain what red-shift really means when we're talking about the EH of a BH?

Thank you.
 
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EH of a BH? Remind me what that stands for.

Redshift for moving bodies is caused by the Doppler Effect.
 
Whovian said:
EH of a BH? Remind me what that stands for.


Event horizon
Black hole
 
Aurora-Sky said:
Event horizon
Black hole

Oh! In which case you have to understand that observers under higher gravitation appear time dilated to observers under lower gravitation. So those of us watching an observer falling into a black hole will see that observer slow down (and, in fact, if I understand correctly, never cross the event horizon), and any sort of waves they send back will have more infrequent peaks due to the time dilation. And so we see redshift in light waves.
 

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