Tagged Questions
1
vote
1answer
85 views
How much time has passed for Voyager I since it left the Earth, 34 years ago?
34 years have passed since Voyager I took off and it's just crossing the solar system, being approximately at 16.4 light-hours away. How much time have passed for itself, though?
-1
votes
1answer
97 views
How do photons experience time? [duplicate]
I know that as velocity approaches the speed of light the time dilation shoots to infinity as shown below.
1)So I want to know how time is perceived from the point of view of the photon?
2)Since ...
0
votes
1answer
91 views
Deriving infinitesimal time dilation for arbitrary motion from Lorentz transformations
I'm trying to derive the infinitesimal time dilation relation $dt = \gamma d\tau$, where $\tau$ is the proper time, $t$ the coordinate time, and $\gamma = (1-v(t)^2/c^2)^{-1/2}$ the time dependent ...
3
votes
3answers
305 views
Why do clocks measure arc-length?
Apologies in advance for the long question.
My understanding is that in GR, massive observers move along timelike curves $x^\mu(\lambda)$, and if an observer moves from point $x^\mu(\lambda_a)$ to ...
8
votes
4answers
553 views
Does the future already exist? If so, which one?
In the NOVA Fabric of the Cosmos program, Brian Greene explains a theory in which there is no "now", or more specifically, now is relative. He describes an alien riding a bicycle on a far off planet ...
2
votes
3answers
682 views
How to calculate time dilation in approaching speed of light
If a spaceship travels close to the speed of light (say, at 0.9c), how do I calculate the time as the spaceship pilot experience it? I thought the formula was
$$t = \frac{t_0}{\sqrt{1-v^2/c^2}}$$
...
4
votes
2answers
586 views
How can time be relative?
I don't understand how time can be relative to different observers, and I think my confusion is around how I understand what time is.
I have always been told (and thought) that time is basically a ...
2
votes
9answers
672 views
understanding time: Is time simply the rate change?
Is time simply the rate of change?
If this is the case and time was created during the big bang would it be the case that the closer you get to the start of the big bang the "slower" things change ...
1
vote
1answer
135 views
Is time the property of an object?
I don't know if the title makes much sense, but hopefully it will become clear with the text.
Temperature is not a property of a point in the three dimensions, but actually of the object occupying ...
7
votes
4answers
595 views
Special Relativistic Time Dilation — A computer in a very fast centrifuge
Ok, I've stumbled onto what I think is a bit of a paradox.
First off, say you had some computer in a very fast(near light speed) centrifuge. You provide power to this computer via a metal plate on ...
5
votes
6answers
2k views
Is time travel possible? Is it possible to go back in time?
I read somewhere that according to relativity, black holes and other space related stuff it is possible to jump into past.
Is it possible for anything to go back in time either continuously or by ...
