What Would the Universe Look Like While Traveling Close to the Speed of Light?

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Discussion Overview

The discussion centers around the visual experience of traveling close to the speed of light, exploring the effects of relativistic phenomena such as aberration, Doppler shift, and length contraction. Participants consider both theoretical implications and imaginative scenarios related to this topic.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants suggest that the view would be influenced by aberration and Doppler shift, with stars in front appearing blue-shifted and those behind red-shifted.
  • One participant speculates that the intensity of light might vary, with red light from the front being more intense and blue light from the back less intense, leading to a potential orange color due to aberration.
  • Another participant raises the idea that the electromagnetic spectrum could shift dramatically, possibly turning light from the front into cosmic rays and light from the back into ultra-low radio waves, with visible light appearing as a rainbow on the sides.
  • Length contraction is mentioned as a factor, with a participant noting that in the stars' frame, the observer's eyeballs would be contracted, while in the observer's frame, the universe itself would be contracted.
  • A participant shares a graphic illustrating how the spherical coordinate system on the sky is deformed due to relativistic effects, specifically mentioning a boost corresponding to a velocity of approximately 0.745356c.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the visual effects of traveling at relativistic speeds, particularly concerning the interplay of aberration, Doppler shift, and length contraction. The discussion remains unresolved with no consensus on specific outcomes.

Contextual Notes

Some claims depend on specific definitions and assumptions about relativistic effects, and there are unresolved mathematical steps related to the application of relativistic velocity addition and its implications for aberration.

Fieldwaveflow
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If you were in a ship, traveling very close to the speed of light, what would it look like? Would the universe look like a bright dot out in front of the ship or would it just be really bright any direction you looked?
 
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What you'll see is influenced by two effects: aberration and Doppler shift. All the stars in front of you will be Doppler shifted towards the blue, while those in back of you will be shifted to the red.

Aberration changes the stars' apparent location. Stars anywhere to your side will have their apparent position moved forward, with the result that the forward hemisphere of your vision will have the light from more stars and they will appear closer together. The backward hemisphere just the opposite. This is also known as the headlight effect. Both of these effects will make the forward hemisphere appear brighter.
 
three

Thank you for the consideration and reply.

I guess red light from the front would be more intense and blue light from the back less intense with green and yellow on the sides being medium intensity. So the aberration might be some kind of orange color between red and yellow.

I wonder what the view and color of the sky would be in a black hole. Maybe black since it has already seen the stars from its outside run out of fuel.

From inside a proton.. There is the shell to consider. It reflects the outside light but there is energy in there somewhere. Maybe like looking at the inside of a curved mirror.
 
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what about

Bill_K said:
What you'll see is influenced by two effects: aberration and Doppler shift. All the stars in front of you will be Doppler shifted towards the blue, while those in back of you will be shifted to the red.

The EM spectrum covers a lot of frequencies. Wouldn't that turn light from the front to cosmic rays and light from the back to ultra low radio waves and leave visible light spectrums somewhere on the sides? Since all visible frequencies are seen at the aberration point I'd think it would have to be white. Scale back the speed some so that the aberration point gets larger and it might look like a circle rainbow with the colors backwards.
 
Bill_K said:
What you'll see is influenced by two effects: aberration and Doppler shift.
What about length contraction? In the stars' frame your eyeballs are contracted, while in your frame the entire universe is contracted.
 
A.T. said:
What about length contraction? In the stars' frame your eyeballs are contracted, while in your frame the entire universe is contracted.
If you use the relativistic velocity addition, you get a different aberration than classically (for high relative velocities):
http://en.wikipedia.org/wiki/Aberration_of_light#Relativistic_Explanation

Does this account for length contraction?
 
As I am right now working on illustrations for my book concerning exactly this topic, here is the graphics I have just made:

zboosts.jpg


It shows how the standard spherical coordinate system on the sky is deformed as a result of the boost described by the following SL(2,C) matrix

[tex]\frac{1}{\sqrt{5}}\begin{pmatrix}2&1\\1&3\end{pmatrix}[/tex]

This particular matrix comes out from the polar decomposition of

[tex]\begin{pmatrix}1&1\\0&1\end{pmatrix}[/tex]

The boost corresponds to the velocity v=0.745356 c in the direction of the black dot. Only (relativistic) aberration effects are shown. Colors are accidental.
 
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