How does gravity affect the path of light?

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Discussion Overview

The discussion centers on how gravity affects the path of light, particularly in the context of light bending around massive objects like stars and black holes. Participants explore the implications of gravitational influence on light's trajectory, including visual representations and interpretations of light paths.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions how light can bend around a star if gravity pulls it inward, suggesting a potential misunderstanding of the gravitational effects on light.
  • Another participant argues that the interpretation of a visual representation is incorrect, clarifying that light rays can travel in various directions and that the angle of intersection with a grid can be misleading.
  • A participant introduces the idea of adding more light rays from a near point source, indicating that they radiate outward.
  • Another participant suggests that light rays from a distant source remain parallel until they enter the gravitational influence of a star, at which point they bend inward.
  • A later reply acknowledges a misunderstanding and appreciates a clearer visual representation of light paths, indicating a shift in understanding.

Areas of Agreement / Disagreement

Participants express differing interpretations of how light behaves in a gravitational field, with some clarifying misunderstandings while others present competing views on the nature of light's path around massive objects. The discussion remains unresolved regarding the initial question posed.

Contextual Notes

There are limitations in the visual representations discussed, as well as potential misunderstandings regarding the alignment of light rays and their interaction with gravitational fields. The discussion does not resolve the complexities of light behavior in gravitational contexts.

Ron777
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Question: If gravity can bend light toward it's source, or even hold it back so to speak (like a black hole), how does light bend around a star like photo attached? It seems if gravity pulls light toward it, the light shouldn't move out and around the star/sun but bend into it?

DSCF7398.jpg
 
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You are interpreting the picture wrong.

The pic is confusing because the light ray is not aligned with the grid. But light rays can go any which way they want. This one happens to be crossing the imaginary grid at an angle.

But rest assured: that light ray is coming directly - in a straight line - from its source.
 
Last edited:
Look what happens if we add more light rays. These rays are from a near point source, so they radiate outward from that point.
 

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But this might make more sense. Here, the light rays are coming from a distant source, so they are all parallel.
They remain parallel until they enter the star's gravity well, then they bend inward.
 

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  • lensing2.jpg
    lensing2.jpg
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Scratch that, now I see what your saying, your first pic shows it, their graphic (that I posted) is what threw me, yours is a better visual showing more light paths, thanks!
 

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