All Questions
Tagged with spacetime speed-of-light
189
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Perception of light speed when traveling between two light sources
I'm struggling with a fundamental understanding of time dilation and special relativity (if I'm correct).
Many online sources explain it as the following:
With the ship moving away from the lightbeam ...
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4
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3
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Constant speed of light violates accelerating expansion of universe?
My question regards the following:
One of the most fundamental principles of Einstein's GR is that all free bodies move through spacetime with constant velocity $c=1$.
However, in 1998 Hubble showed ...
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3
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Measuring the Hubble Constant
Attempts to measure the expansion of the universe have come in various forms. The recent Cosmology Crisis (https://www.space.com/why-is-there-a-cosmology-crisis) has me pondering the expansion rate ...
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Lorentz transformation equations: an insight [closed]
Let Bob be moving towards the positive $x$-axis and Alice be stationary at the origin. Then the Lorentz transformation gives:
$$t' = \gamma\left( t- \frac{v x}{c^2}\right)$$
where $t'$ is the time of ...
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If you travel on car with nearly the speed of light and turn on the car headlights: will it shine in gamma light instead of visible light?
If you travel on car with nearly the speed of light and turn on the car headlights: will it shine in gamma light instead of visible light?
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Time dialtion when objects run in the same direction
Just trying to understand the basics.
I saw some videos claiming that when you run towards light the speed of light may appear to be faster than C therefore time corrects it by being slow.
Now the ...
user325851
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1
answer
76
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Two spaceships traveling through spacetime and meeting at the same exact position and time
We have spaceship "A" traveling at a velocity of 99% of the speed of light for 2 seconds in the positive $x$-direction and then traveling at a velocity of half the lightspeed for 1 second in ...
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How speed of light is absolute/constant if time (denominator) is relative?
Speed is path / time.
How speed of light in vacuum can be always constant if denominator (time) is relative, its changing?
If speed of light must be constant then path must be changed as well?
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Making use of principles concerning relative and absolute velocity, can we move an object at a velocity that is greater than light?
I am new to physics, so please do not get angry if this is a stupid question.
First, let's imagine that we are sometime in the future where we have an extremely fast spaceship which is travelling in ...
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2
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Does it make sense to create a spacetime diagram in respect to another velocity besides the speed of light?
I'm trying to understand the application of special relativity into things where it's velocity might be none regular units. Just for argument sake, let's say that the distance is measured in some unit ...
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This question is about time dilation but a bit different
See the image below-
Here I have decribed a scenario related to relativity theory. A spaceship is travelling at "V" velocity relative to a man standing on planet. The Spaceship's frame is ...
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answer
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Speed of light measurement using a star mass, just like a satellite orbits the earth
This is just an idea than came to my mind last night, would it be possible to, launch a satellite, close enough to the sun (To be safe for it) to light a laser, somewhere close enough to the sun, ...
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2
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If we find a star exploding 100 light years away, that means it happened 100 years before? [duplicate]
So can someone please help me with this? Can someone make the answer as simple as possible?
So my question is if we see a star exploding like 100 light-years away, that means that star exploded 100 ...
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3
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189
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Is the speed of light the limit or just everything moves at this speed?
When I was a little kid, I was fascinated by the fact that we are not able to surpass the speed of light. I imagined a giant spaceship trying to catch a light beam like superman tries to catch flash.
...
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Is This Why the Speed of Light is Universally Invariant?
Please could you tell me if the following is an original thought or whether this is already understood. I ask because I am undertaking a piece of writing on the nature of spacetime. What I discuss ...
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