Light Acceleration Near Black Holes: The Effects on Gravity

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Discussion Overview

The discussion revolves around the behavior of light in the vicinity of black holes, particularly whether light accelerates as it approaches a black hole and how gravity affects its trajectory and frequency. The scope includes conceptual and technical aspects of physics related to gravity, light, and vector mechanics.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants propose that while light does not change speed, it does change direction due to the gravitational influence of a black hole, which can be described as an acceleration of its velocity vector.
  • Others argue that the gravitational potential does not accelerate light in terms of speed but alters its frequency, with references to the relationship between momentum and frequency as described by Planck's constant.
  • A participant questions the understanding of light's behavior, suggesting confusion about the nature of light traveling and its position over time.
  • There is a mention of the concept of geodesics, where light follows a curved path in a gravitational field, contrasting with its straight-line path in flat space.
  • Technical details regarding the equations relating energy, frequency, and momentum of light are discussed, with some participants seeking clarification on notation.

Areas of Agreement / Disagreement

Participants express differing views on whether light accelerates in the context of gravitational fields, with some asserting that it does due to changes in direction, while others maintain that its speed remains constant. The discussion remains unresolved with multiple competing views.

Contextual Notes

There are unresolved questions regarding the definitions of acceleration in the context of light and the implications of changing frequency versus speed. Some participants also exhibit confusion about the nature of light and its interaction with physical objects.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in general relativity, the behavior of light in gravitational fields, and the foundational principles of physics related to momentum and energy.

Moogle
Since the gravity of a black hole affects light, does a baem of light accelerate when it nears a black hole ? Just wondering.
 
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Originally posted by Moogle
Since the gravity of a black hole affects light, does a baem of light accelerate when it nears a black hole ? Just wondering.
It doesn't change speed -- but it changes direction.

Physicists refer to any change in the velocity vector an acceleration, though -- so yes, the light does accelerate. Its velocity vector does not change in magnitude however, which means the light does not change speed.

- Warren
 


Originally posted by chroot
It doesn't change speed -- but it changes direction.

Physicists refer to any change in the velocity vector an acceleration, though -- so yes, the light does accelerate. Its velocity vector does not change in magnitude however, which means the light does not change speed.

- Warren
nonsense.
when direction changes there are all three: normal, tangentional and torsional changes of the vector.
and how exactly do you find light to be cabable of traveling?
is it in a sense light changes position?
in my room now the lights are on.where do i find the light now?
how do i ensure the light after awhile has gone from there?

finally can you put light on bread and eat it?
 
dock, what the heck?? Are you capable of making sensible posts at all anymore, and even of understanding extremely basic vector mechanics?
 
A light beam always follow the shortest path through the vacuum. If space is flat that path is a straight line. But near a gravitational source it is a curved line, called a geodesic. Light follows it.

The gravitational potential will not acclerate the ligh, but it will change its frequency. For light, momentum is exhibited as frequency according to the equation momentum equals Planck's constant times frequency. p=h[nu].
 
Originally posted by selfAdjoint
A light beam always follow the shortest path through the vacuum. If space is flat that path is a straight line. But near a gravitational source it is a curved line, called a geodesic. Light follows it.

The gravitational potential will not acclerate the ligh, but it will change its frequency. For light, momentum is exhibited as frequency according to the equation momentum equals Planck's constant times frequency. p=h[nu].

Or E = h ν

and p = E/c = hν /c
 
Originally posted by marcus
Or E = h ν

and p = E/c = hν /c

that thing that looks like a vee is supposed to be a nu.

I used & nu ; (without the spaces)

is there another way to get nu?

Let's try [ nu ] (w/o the spacing)

E = h[nu]

E/c = h[nu]/c
 
dr-dock:
Can you put light on bread and eat it?

Yes, but that is a topic for another thread.
 

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