Is light speed faster coming from a smaller star?

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Discussion Overview

The discussion centers around the behavior of light in relation to gravitational fields, particularly in the context of stars with varying gravitational pulls and black holes. Participants explore concepts such as the speed of light, gravitational lensing, and the implications of black holes on light's path and energy.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions whether light would travel faster away from a star with less gravitational pull, suggesting a relationship between gravity and light speed.
  • Another participant asserts that gravity does not slow light, emphasizing that light always travels at the speed of light (c).
  • Several participants discuss black holes, with one noting that black holes do not slow light but change its path through gravitational lensing.
  • Another participant elaborates that light cannot escape a black hole because the spacetime is bent so strongly that light's path is confined within the event horizon.
  • There is mention of redshift, with a participant explaining that light traveling directly outward from a black hole loses energy and is redshifted significantly.

Areas of Agreement / Disagreement

Participants generally agree that light travels at speed c and that black holes do not slow light but alter its trajectory. However, there is no consensus on the implications of gravity on light speed in the context of different stars, and the discussion remains unresolved regarding the initial question posed.

Contextual Notes

Some assumptions about the nature of gravity and light are not fully explored, and the discussion includes varying levels of understanding among participants, which may affect the clarity of the arguments presented.

PaulRacer
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If gravity slows light, would light be pushed faster away from a star that has less gravitational pull? Would we still observe it at c?
 
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What about black holes?
 
What about them?

[edit] And to save some time, does my previous post have anything to say about this question...?
 
Last edited:
PaulRacer said:
What about black holes?

I'm pretty amateur about all this but even I know that black holes don't slow light, they change it's path. The effect is called gravitionally lensing.

Now when it comes to light not being able to escape a black hole... I'm not sure why that happens...
 
Exactly the same reason. Spacetime is bent so strongly around a black hole that the start and endpoint of a light rays path is within the event horizon, any light leaving the 'surface' of the black hole will be bent back onto it.
 
Salbris said:
I'm pretty amateur about all this but even I know that black holes don't slow light, they change it's path. The effect is called gravitionally lensing.

Now when it comes to light not being able to escape a black hole... I'm not sure why that happens...

Light traveling directly outward from the black hole is redshifted so much it loses all of its energy. Light traveling at an angle out from the black hole is bent back in towards the black hole.
 
Ok, sorry for the wasted space. Light travels at c...no exceptions. Thanks!
 

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