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LightningInAJar
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- Time dilation without speed or gravity?
Can time dilation vary without a gravity well or accelerating a viewer towards light speed? Are there other variables that affect the flow of time?
The two things you refer to are not the same anyway; the common usage of the same term, "time dilation", to refer to both is a source of confusion, not understanding.LightningInAJar said:Can time dilation vary without a gravity well or accelerating a viewer towards light speed?
What you are calling "the flow of time" is an artifact of coordinates, not a physical thing. As far as you are concerned, your own time always flows at the same rate--1 second per second. And if you are not co-located with someone else, there is no invariant way for you to specify how their "flow of time" relates to yours.LightningInAJar said:Are there other variables that affect the flow of time?
Light speed, or anything close to it, is irrelevant to your question. Velocity time dilation has been measured here on Earth with an airplane and it measured every second of every minute of every day by the GPS system. The magnitude of relative motion determines the AMOUNT of time dilation but not its existence. That is, time dilation due to motion exists for ANY speed (it's just hard/impossible to measure for slow speeds such as human walking).LightningInAJar said:Summary:: Time dilation without speed or gravity?
Can time dilation vary without a gravity well or accelerating a viewer towards light speed? Are there other variables that affect the flow of time?
No. Time runs slower near the BH when viewed from Earth and time on Earth runs faster when viewed from near the BH. Reread post #3 where this was explained.LightningInAJar said:When near a black hole time runs faster compared to on earth?
Only from the frame of the Earth. From the frame of the moving object time is slower on the Earth.When traveling half the speed of light time runs slower compared to on earth?
What did you have in mind? I'm not aware of any such thing.I'm asking about other things besides gravity and acceleration that affect relative passage of time?
Suppose two objects start at the same point in spacetime and, after taking different paths, end up at the same point as each other again. Then, the amount of time that has elapsed for each is a function only of their path through spacetime. Nothing else is relevant. Only the description of the relevant portion of spacetime and the two paths (aka worldlines).LightningInAJar said:When near a black hole time runs faster compared to on earth? When traveling half the speed of light time runs slower compared to on earth? I'm asking about other things besides gravity and acceleration that affect relative passage of time?
The point is that "time runs faster" is a bad way to think about this. It's just that the elapsed time along a worldline is the equivalent of distance along a path through space, and some routes from A to B are shorter than others.LightningInAJar said:When near a black hole time runs faster compared to on earth? When traveling half the speed of light time runs slower compared to on earth?
Acceleration doesn't really affect anything - it's perfectly possible to construct variants of the twin paradox to demonstrate this. But the key point is that all of the clock effects in relativity boild down to "different routes between the same places may have different lengths". Any time you pop to the shops and your other half stays at home you experience different elapsed times - in fact you really have to plan carefully to have the same elapsed time along two non-identical worldlines.LightningInAJar said:I'm asking about other things besides gravity and acceleration that affect relative passage of time?
Time dilation is a phenomenon in which time appears to pass slower for an object or person in motion compared to a stationary observer. This is due to the effects of either speed or gravity on the passage of time.
According to Einstein's theory of relativity, as an object's speed increases, time appears to pass slower for that object. This is because the faster an object moves, the more energy it requires, and this energy can distort the fabric of space-time, causing time to slow down.
Gravity can also affect the passage of time. The stronger the gravitational pull, the slower time appears to pass. This is because gravity can bend the fabric of space-time, causing time to slow down in its presence.
Yes, there are other variables that can affect time dilation, such as acceleration and the curvature of space-time. These variables can also cause time to pass slower for objects in motion.
Yes, time dilation has been observed and measured in various experiments, such as with atomic clocks on airplanes or satellites. However, the effects of time dilation are only noticeable at extremely high speeds or in the presence of strong gravitational fields.