Define Red-Shift: Explaining BH Event Horizon

  • Thread starter Thread starter Aurora-Sky
  • Start date Start date
  • Tags Tags
    Red-shift
AI Thread Summary
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.
Aurora-Sky
Messages
2
Reaction score
0
Could some one explain what red-shift really means when we're talking about the EH of a BH?

Thank you.
 
Astronomy news on Phys.org
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.
 

Thread 'Potential biosignature found in Mars rock'

Publication: Redox-driven mineral and organic associations in Jezero Crater, Mars Article: NASA Says Mars Rover Discovered Potential Biosignature Last Year Press conference The ~100 authors don't find a good way this could have formed without life, but also can't rule it out. Now that they have shared their findings with the larger community someone else might find an explanation - or maybe it was actually made by life.
View full post »

Thread 'Does it make sense to build new radio telescopes?'

TL;DR Summary: In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect alien signals, it will further expand the radius of the so-called silence (or rather, radio silence) of the Universe. Is there any sense in this or is blissful ignorance better? In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect...
View full post »

Thread 'Our Beautiful Universe - Photos and Videos'

This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...
View full post »

Similar threads

I Why don't any stars "look" red? red shift
Replies
7
Views
3K
I How can I calculate red shift for intragalactic bodies
Replies
2
Views
1K
I Black Hole Event Horizon Hypothesis
Replies
6
Views
2K
Red shift of light from galaxies
Replies
11
Views
3K
"Amount" red light in red shifted light
Replies
8
Views
2K
I Tidal effects on event horizon of binary rotating BHs
Replies
6
Views
842
B Detection of red-shifted photons near an event horizon
Replies
7
Views
916
I How do you get to the conclusion that there is accelerating expansion?
Replies
23
Views
2K
I Calculating average density of the Universe
Replies
2
Views
3K
Collision of massive star with black hole
Replies
13
Views
2K

Hot Threads

Recent Insights

Back
Top