Questions tagged [time]
Time is defined operationally to be that which is measured by clocks. The SI unit of time is the second, which is defined to be
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Does quantum entanglement arise from perpendicular time vectors? [closed]
From what I understand, "quantum entanglement" is a phenomenon where certain information travels instantly between entangled particles, regardless of distance in space.
When thinking of ...
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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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Speed is equal to distance divided by time but is this correct?
In this study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9784821/, the distance the punch travelled from start to impact is 0.49 meters and the time taken from start of punch (that's it, they define ...
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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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Non-orientable time
Consider the following toy classical physical theory.
Let the theory take place on a fiber bundle $(E, M, \pi, F)$ such that $M$ is a one dimensional manifold interpreted as time. Define an action $S[...
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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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Can anyone please give some explanation in terms of the frequency domain of the time evolution?
This might be a silly question. But I was puzzled for a long time, even some comments are greatly appreciated.
Is it possible to claim that "All the time domain evolution can be thought of ...
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For an observer on a spaceship moving near the speed of light away from Earth, would Earth be moving near the speed of light in the other direction? [duplicate]
There is something I don't understand about time relativity in examples given in internet, television, etc. Supposedly if a spaceship takes off from Earth and moves closer to the speed of light, time ...
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A change in the unit vector over a finite time interval
how we can write the change in unit vectors over a finite time interval, the change in unit vectors in an infinitesimally small-time interval 'dt' is given by the magnitude of the really small angle ...
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Is there any difference between Wick time order and Dyson time order?
Reading A Guide to Feynman Diagrams in the Many-Body Problem by R. Mattuck, I am getting the feeling that I missed something subtle related to time order. When deriving the Dyson series for the ...
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To understand relativity in time with time dilation experiment
The time dilation experiment involves two frames in relative motion, let one at ground and other at train with velocity V. The light clock runs faster in rest frame, as seen by an observer A at rest ...
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Why is the term 'Accuracy of 1 part in $x$' used?
My question stems from how we measure the accuracy of Caesium clocks. Most Caesium clocks are said to have an accuracy of '$1$ part in $10^{14}$.'
I understand that the terminology means to convey ...
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Entrainment of air and timekeeping of a mechanical watch at high altitude (problem attributed to A. H. Compton)
S. K. Allison told1 this Fermi problem:
During the war, Professor A. H. Compton, Enrico Fermi, and I [Allison]
were traveling together to visit the Hanford Plutonium Plant in the
state of Washington. ...
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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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Relativity explained using sound instead of light
A friend of mine asked me to explain Einstein relativity to him, and I tried to use a methaphore using sound, however for some reason it does’t quite work:
imagine there are 2 people with a clock, ...
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