All Questions
12
questions
6
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5
answers
4k
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Wikipedia states that the relativistic Doppler effect is the same whether it is the source or the receiver that is stationary. Can this be true?
According to Wikipedia, the relativistic Doppler effect is simply the classical Doppler effect for a stationary source, $1-v/c$, times the relativistic time dilation, $1/\sqrt{1-v^2/c^2}$ (where v is ...
- 131
0
votes
1
answer
54
views
Symmetry and Doppler
If relativity is symmetrical (triplets moving away and returning to the center) then what happens to the Doppler effect as seen by the moving triplets?
A B C
A should see C moving (Doppler) away/to ...
- 1
5
votes
1
answer
610
views
What happens if you're on a spaceship accelerating close to the speed of light, but then stop accelerating?
So most people want to ask what happens if you go super-close to the speed of light and try to go a bit faster. I want to know what happens if you stop accelerating at close to $.99c$. Not decelerate, ...
2
votes
1
answer
142
views
Twin Paradox doppler resolution
I've been doing some doppler thought experiment around the twin paradox,
(wikipedia)
The paradox centers on the contention that, in relativity, either twin could regard the other as the traveler, in ...
- 49
0
votes
2
answers
547
views
What is effect of relativistic speeds on blue and red objects?
We know, As per Doppler effect, if an object travels with speed close to that of light, if appears red if it goes away from observer and it appears blue if it comes towards the observer.
My question ...
2
votes
1
answer
186
views
Could Mars be used to measure the one-way speed of light? [duplicate]
I just watched this Veritasium video, explaining the difficulty of measuring the one-way speed of light. The presenter explains that a round-trip will always average out to $c$ even if the speed in ...
- 2,172
1
vote
1
answer
245
views
Doppler effect in light (Observer moving away from source)
I understand this intuitively and can picture it in my head, but when I do it on paper, the result is a sign difference that I cannot understand
According to this diagram the wavelength = ct-vt = t(c-...
- 753
1
vote
4
answers
470
views
Does time really slow down in relativity, or is it an illusion caused by the Doppler shifting of light? [duplicate]
Does time really dilate, or is it only how we perceive time, which is in the form of light waves. When an object moves away from another object at very high speeds, the light takes longer to reach it ...
- 21
-1
votes
1
answer
922
views
Is length contraction in Special Relativity the same as the Doppler Effect?
In my further reading of Special Relativity, the idea of length contraction when travelling at the speed of light is such that the length gets "squished" in the direction of travel.
This immediately ...
2
votes
3
answers
397
views
Quick check: relativity, rockets, clocks and the equivalence principle
One common thought experiment that introduces relativity on gravitational fields is the "clocks on an accelerating rocket":
Paraphrasing Mr. Feynman:
Suppose a rocket, with two clocks, one on each ...
user133382
2
votes
4
answers
4k
views
Is the speed of light constant in all directions?
Consider the shape of the waveform emitted by a moving source:
(with the horizontal axis "x" and the vertical axis "y").
According to the stationary observer, the wavefront of a short pulse emitted ...
- 340
30
votes
5
answers
3k
views
What do you really see on a line of clocks as you pass by them at high speed?
According to my understanding of SR, if I travel at 0.8c relative to a line of clocks, I should see the clocks in front of me going 3 times faster than my own, and those behind me going 3 times slower ...
- 1,903