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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What happens if we let time expand in the FLRW metric?
If we multiplied the time differential (dt) by a scale factor that depends on time in the FLRW metric, what would this imply on cosmology? In particular, what are its implications on the cosmological ...
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Relativity Time Dilation with a twist- Apparent Paradox [duplicate]
Imagine identical triplets on Earth: Ana, Barb, and Evelyn. Ana launches in a spaceship traveling .85c. She knows time on Earth is elapsing 1.9 times faster.
A few months later, Barb launches in a ...
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If I levitate at the same place will I come back to the same place after Earth taking it's one complete revolution? [duplicate]
so i have this question if i mean if we can levitate and decide to levitate and not stay on ground but at a place to look the ground, and we that earth rotates right and we rotate along with it cause ...
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Are Hilbert spaces in Quantum Mechanics time-dependent?
I'm a mathematician, and am trying to grasp, at least on its surface, the mathematical foundations of quantum mechanics... but there is something that seems just odd with the mathematics.
Suppose i ...
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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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In a uniformly accelerated motion experiment, the acceleration can be attained from $V_{ave}$ vs. $t/2$ and $x$ vs. $t^2$ graph. How is this possible?
Specifically, in the experiment, we had to release a glider from an inclined plane (that had an angle of inclination of 10 degrees). We had to calculate the time it reaches the final position. We had ...
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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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How would voltage change in time in an electrolytic solution?
I'm building a teaching model and a question came up that isn't very clear to me. I would like some help.
The voltage of a sphere (~5 cm in diameter) uniformly charged, in this case positively as in ...
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Relativity of Simultaneity- Train Experiment with 2 Countries signing Contract
I am having a hard time understanding the implications of one of the popular variations of the thought experiments associated with Relativity of simultaneity. The example goes as follows. 2 countries ...
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Since the instant of the big bang, has the progression of the universe been entirely determined?
[Note I am asking up to, but not including, consciousness as this bleeds into philosophy and is a much messier question]
Assuming that the laws of physics have remained constant across space & ...
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Can I find $\frac{dm}{dt}$ where $m$ is the relativistic mass of a particle?
So, recently I learned the basics of Special Relativity, and I found out that the mass of a body increases with the increase in its velocity as given by the Relativistic Mass equation:
$m=\frac{m_0}{\...
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Ensuring Regularity of Time pieces [closed]
Physics defines, I'm told, that time is "whatever" the clock measures. Time is a measurement means it has to have a unit. So let s (seconds) be the unit of time.
If time measurement is ...
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Is the size/age of the universe dependent on your velocity? [duplicate]
As Photons do not experience time or space, then according to my thought experiment, all photons must occupy some kind of singularity as well as what WE observe from earth.
I was also thinking that ...
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Product of two 4 positions without writing the components
I was able to solve the first part of the following question by expanding the terms as vectors
I can't understand how to do it without expanding so I had a look at the answers.
I understand how we ...
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