All Questions
Tagged with time general-relativity
361
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Do clocks tick faster when gravitational forces are weaker?
A professor last year taught us that "gravity slows clocks," when teaching about the relationship between gravity and time. This led me to think about places, such as intergalactic space, ...
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Does it make sense to talk about time in absence of matter? [duplicate]
The equations of general relativity should predict (although I might be wrong) that in absence of mass the spacetime is everywhere flat. That is, time is the same everywhere. However, I'm not sure ...
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Does time arising from entropy agree with GR?
There's a theory that the direction of time arises from entropy and the correlations (interactions) between bodies. However, I don't see how this would incorporate the effects of General Relativity, ...
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Is the meter relative to time?
Is the meter relative when we are near the speed of light?
I was reading a physics book and I found that the meter is the length that light travels for an amount of time, so since time is relative ...
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How do I interpret the time axis in a diagram with multiple light cones?
Light cones are often drawn on a spacetime diagram that has a directional time axis like the fourth one on this page:
There is a time axis, and all of the light cones are align with it because this ...
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Comparison of clocks running at different heights in a gravitational field
I hope this question has not yet been asked. If so then please link me to the answer.
If I build an apparatus which, on flicking a switch, sends a light beam, a distance to a mirror, and reflects it ...
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Need help to clarify understanding example of time nature from Hawking's book "Briefer History of Time"
I'm reading Hawking's book "Briefer History of Time" both in Ukrainian and Russian languages and found a possible translation mistake in this paragraph (last page of "Chapter 6. CURVED ...
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Gravitational effects on a celestial body and the difference between a pendulum and a regular clock
Imagine a planet with the same properties as Earth, this time moving in an elliptical orbit around a heavy star of a large number of solar masses. Also imagine that the surface of this planet is as ...
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Measurement of the velocity of a celestial body by means of (relativistic and classical) gravitational effects on clocks
Imagine a planet with the same properties as Earth, this time moving in an elliptical orbit around a black hole of a large number of solar masses. Also imagine that the surface of this planet is as ...
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Is spatial distance objective?
While reading some papers on Einstein's theory of relativity, seeing how the flow of time is not the same for everyone, a doubt occurred to me:
Let us imagine a photon moving in a well-defined space ...
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Common clock reference of Big Bang
Relativity tells us that there is no preferred reference frame, yet current cosmology does operate on the hypothesis that all points in the observable universe originate from the same big bang ...
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How do they set the clocks on spacecraft visiting several other planets?
Scientists have sent spacecraft into distant space passing nearby other planets on the voyage. How do they set the clocks to adjust for kinetic time dilation (special relativity) and gravitational ...
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The synchronized clocks on earth's surface: at which observer's rate are they beating?
From what I understand, the time rates (I'm not speaking about absolute times) of all clocks on earth's surface are synchronized. This means that, say, a mobile phone's clock is generally not beating ...
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Time in the Standard Model of Cosmology
Beyond a formal preference for background independence, what is stopping us from setting cosmological time as a de facto universal timeline, analogous to newtonian absolute time? General relativity ...
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Does String Theory address the problem of time?
According to the argument in this post, a theory of Quantum Gravity should not be compatible with the notion of time evolution. This is also called "The Problem of time".
However, the target ...
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