Questions tagged [speed-of-light]
The speed of light is a fundamental universal constant that marks the maximum speed at which energy and information can propagate. Its value is $299792458\frac{\mathrm{m}}{\mathrm{s}}$.
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How does information 'move'? [closed]
Information cannot be transmitted faster than the light. However, I am confused about the meaning of 'transmission' of information. How does the information 'move'? If I calculate the future state of ...
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About information transmission speed [duplicate]
Einstein says information cannot be transmitted faster than light.
Say I set an alarm that ring at 9:00 am. I go to school, and wait until 9:00 am. Then I tell my friends that my alarm rang. If the ...
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Speed of light in Michelson-Morley experiment
The (failed) goal of the Michelson-Morley experiment was to detect the motion of the Earth with respect to the hypothetical ether. As far as I understand (e.g. from the exposition in Feynman’s ...
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The speed of light is constant?
In the proof that the speed of light is a constant we make the assumption that space at large scales is homogeneous, but there are patches of space where the density is higher and there are patches ...
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Has there been any experiment showing that the velocity of light in solids changes in the presence of a magnetic field?
Has there been any experiment showing that velocity of light in solids changes in if magnetic field is introduced? We know that the polarization of light traveling through some solids may be altered ...
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What is the speed of light in case of Critical Angle?
When light travels from an optically denser to a rarer medium, it bends away from the normal and at a specific angle of incidence, the angle of refraction is ${90}^{\circ}$. When the angle of ...
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Time Passage Naked Eye Viewing Distant stars [duplicate]
My question surrounds the time it takes to see a star and it's ending. OK, a star is 100 light years away, so it takes 100 years to see the light from it when that star 1st begins sending light. 100 ...
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Is it possible to attain (near) light speed in space?
As there is no drag in space/vacuum, is it possible to actually send a probe with enough fuel to have it achieve the speed of light or a value very near to it? Since there are not many significant ...
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Spacetime that allows matter to rotate faster-than-light
Is there a solution to Einstein's equations which allows:
the object to be rotating at sub-light speed when viewed from within itself.
for a distant observer the object to rotate at superluminal ...
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How much of an observer's field of view will be black upon crossing an event horizon? [closed]
The aberration of light will cause an observer to still see a black hole as "distant" when the event horizon is crossed.
This means that if the observer looks directly toward the center of ...
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Do events very far away happen in a different timeline?
I am not sure how to ask this question in a concise manner so I am sure somebody out there explained it but I cannot seem to find it.
So I recently watched some videos explaining that $c$ not only ...
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Relativistic Doppler Shift vs Classical Doppler Shift Contradiction
In classical/Newtonian mechanics, the doppler shift (for light) can be expressed as:
$$ \frac{f_r-f_s}{f_s}=\frac{1+\beta}{1-\beta}-1 $$
In relativity the doppler shift can be expressed as:
$$ \frac{...
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Amateur Shower Thought Question About Time and Space
Apologize in advance if this is the wrong group. I often watch Netflix shows about blackholes explained in a nutshell or laymen’s terms.
I had a recent thought/scenario that may relate to some ...
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What if an object is approaching us at near the speed of light?
Suppose an object that is 100 light years away is approaching us at 0.99c. It would take about 100.1 years for the object to reach Earth. But the light that this object emitted when it began the ...
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Can two laser diodes of the same type and wavelength, be synchronized to emit light in the same phase, while working in a CW mode.?
Can two laser diodes of the same type, power and wavelength, be synchronized to emit light with lightwaves in the same phase, while working in a continuous wave mode (CW) ?
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