All Questions
10
questions
1
vote
1
answer
50
views
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, ...
12
votes
3
answers
1k
views
How quickly does spacetime that's been deformed return to "flat" after the deforming mass moves on?
I'm just curious. I've no physics eductation beyond GCSE. I've searched and searched for an answer but haven't been able to find one. I'm guessing it's at the speed of light??
To elaborate; I'm ...
0
votes
1
answer
90
views
Speed of light on and through a hollow planet [duplicate]
First of all, this is a thought experiment regarding faster-than-light communication.
Say you had an immense hollow planet that was made of some heavy material such as neutron-star dust.
Due to the ...
- 23
2
votes
1
answer
337
views
Gravity, acceleration and reference frames [closed]
Let’s say the universe was empty and suddenly an astronaut and the sun appeared 2 light years apart. Using the reference frame of the Astronaut, would he be pulled towards the sun as soon as he can ...
- 31
-1
votes
1
answer
115
views
If strong gravitational fields bend and slow down time, how can travelling near the speed of light do the same?
I was wondering how travelling near the speed of light could slow down time, seeing that light approaching a strong gravitational field would get curved and therefore reach its destination in a longer ...
1
vote
3
answers
206
views
Can gravity transfer to the other side of the universe?
Since the speed of gravitational wave is limited by the speed of light, and a light can never transfer to the other side of the universe because it is expanding so fast. So does that means gravity ...
- 132
2
votes
1
answer
153
views
Gravity is Instant [duplicate]
Without being able to manipulate gravity. How do we know that gravity is restricted to the speed of light? or gravitational effects from an exploding star would be felt (if we were near) before we ...
- 1
0
votes
1
answer
302
views
Is gravity instantaneous? [duplicate]
I want to know if (hypothetically) a star appears out of nowhere at a certain distance (say 20 light seconds) away from me, how long will it take for me to get the feel of it's gravity? Will I know it ...
- 141
1
vote
2
answers
88
views
Gravity and the Speed of Light
Let's assume that I am on an airplane that is at about 4,000 altitude and now let's also assume that I am standing on one of the wings with a light torch, if I point the light torch below to the ...
- 457
2
votes
3
answers
453
views
What is the cause the light is affected by gravity? [duplicate]
I know that photons have no mass and that a photons exist only moving at the speed of light. So what is the cause that a massive astronomical object can bend a ray of light?
I have two thoughts, but I ...
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