All Questions
Tagged with spacetime speed-of-light
189
questions
-4
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1
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89
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Are length and time mathematically equivalent scales? [closed]
So, say we define a clock as measuring an electronic oscillation on a quartz atom, eg, a normal clock.
The fine structure constant is a relation between the electron mass and C. If C goes up, electron ...
- 1
1
vote
1
answer
112
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How to show mathematical equivalence between the idea of relativistic mass and the geometric explanation of why massive objects can't reach $c$?
I've frequently seen two different explanations for why, in SR, it's impossible for an massive object to reach $c$:
As a massive object approaches $c$, its kinetic energy starts being converted to ...
- 2,327
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0
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24
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Does time slow down for light according to relativity? [duplicate]
According to Einstein's theory of relativity
Time slows for a individual who moves at the speed of light and time goes backward if the individual is faster than the speed of light.
So , is it that for ...
- 725
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0
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40
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Twin paradox symmetry in time dilation during the first leg [duplicate]
I was watching this Ted Ed video on Youtube about the twin paradox and found the explanation with the spacetime graph a bit confusing. At 3:00 in the video, they show a graph and explain how bursts ...
0
votes
1
answer
131
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Relativistic Mass Relative to a Stationary Observer
I know what you’re thinking, “Not another question on Relativistic Mass.” I’ve spent the better part of a day going down the general and special relativity rabbit holes, and I can not find where this ...
-1
votes
1
answer
112
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What speed of light means? [closed]
speed of light means moving through space with the same speed you move through time?
or to move "only" through space and not through time?
Does this mean that you exist in two (or more) ...
- 77
-3
votes
1
answer
83
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Can you experience multiple points in time at a specific point in time? [closed]
So from my understanding, light takes time to travel to our eyes. So everything we see is from the past, right? So does that mean that at a specific point in time, we are seeing simultaneously a point ...
- 13
3
votes
2
answers
418
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Converting Seconds to Millimeters
The concept is that time is another dimension, complementary to those we can observe and measure directly. For those three, I can take a ruler and measure how many millimeters one point in space is ...
- 133
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3
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200
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Is it possible to prove from relativity that massless things have proper time of zero?
Is it possible to come to the conclusion that something massless has proper time of zero, thus moves at $c$? I have seen many arguments for why moving at the speed of light means proper time is zero, ...
- 1,261
0
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2
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61
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Can Shapiro Time Delay cause light in a vacuum to go faster than c as viewed from a remote reference frame?
I know within any reference frame the speed of light is fixed. But it has been shown that light does appear to slow down when passing massive objects as viewed from a remote reference frame per https:/...
- 319
1
vote
1
answer
80
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Why is the time part of the space-time with exactly second degree?
Why is exactly $n = 2$ in the equation
$$\begin{array}{*{20}{c}}
{{{\left( {ds} \right)}^n} = {{\left( {c \cdot dt} \right)}^n} - {{\left( {dr} \right)}^n}}\\
{dr = \sqrt {{{\left( {dx} \right)}^2} + {...
- 201
0
votes
1
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39
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Does local gravity change when approaching the speed of light? (Relativistic mass) [duplicate]
Let's say we'd transform earth into a giant space ship and had some planetary drive that can accelerate it without burning any kind of fuel (so the amount of matter on earth stays the same - we'd ...
6
votes
2
answers
531
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Does kinetic energy of an object curve spacetime? [duplicate]
Based on general relativity mass and energy distribution curves spacetime. Thus, if an object with 1kg rest mass moves with constant speed and has a speed very close to speed of light, then it has an ...
- 947
1
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2
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274
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Time and speed of light in Relativity
Time running slower near a massive object, but the speed of light does not really change near a massive object, according to Relativity - it just curves. Is not time directly related to the speed of ...
- 103
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2
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117
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How would the following image look like, if we didn't use $ct$ for time?
I just wonder how spacetime would look like if we didn't use $ct$ for $t$ and we just used $t$ instead?
I guess the $t$-axis would just scale. Would that mean that, the hyperbolas would be very hard ...
- 107