Questions tagged [faster-than-light]
"Faster-than-light", also known as superluminal velocities, refers to any sort of travel at a speed greater than the speed of light. Prohibited in mainstream physics due to the Special theory of relativity.
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In SR, why do we claim length contraction rather than faster than $c$ travel in the rocket frame? [closed]
In special relativity, a rocket traveling at .5c will take .86 years (in the astronauts frame) to travel 1 light year (in a stationary observer frame). There are two possible ways to look at this
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Please help me with this paradox [closed]
Physicists believe that some galaxies are moving away from us at faster than the speed of light. A galaxy that is moving away from us at faster than the speed of light would be moving backwards in ...
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Whats wrong with concept of "faster than light" information transfer device? (not about technical implementation, just about theory) [closed]
Yesterday, while lying in bed, an idea came to me, and I don’t understand why it won’t work?
Setup:
1.1) Two infinite stores of entangled pairs of photons, each connected to a double-slit device.
1.2)...
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Could a delayed choice Aharonov-Bohm experiment be used for FTL information transfer?
Tim Maudlin about a delayed choice Aharonov-Bohm experiment, the section between 1:35:00 and 1:38:30
In the interview above Tim Maudlin mentions some sort of delayed choice Aharonov-Bohm experiment. ...
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If the speed of causality changes, could you go FTL?
In the middle of some research, I reached a sort of confusion that I’d like to sort out. In flat space FTL is impossible, because in a Minkowski metric,
$$\mathrm{d}s^2=c^2 \mathrm{d}t^2-\mathrm{d}x^2-...
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Transmitting Data faster than the speed of light using entangled particles [duplicate]
If we have a pair of super-asymmetrical entangled particles, and move them a light year away so that they retain their quantum entanglement, and we set a clockwise spin (or vertical polarization) as 0 ...
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Does the fact that we are able to see CMBR implies that universe expanded faster than light?
Supposedly, the universe underwent rapid expansion immediately after the big bang, surpassing the speed of light. If we can detect remnants from that era, does this suggest they moved faster than ...
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How to make meaningful experiments and the methods of doing so [closed]
I have thought of an experiment to test for statistical significance in a quantum entangled system. The proposed experiment is as follows:
Suppose there are 3 entities all in a straight line from each ...
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Faster than the Speed of Light with No Cerenkov Radiation
A charged particle in vacuum and stable motion would induce a time-variant but non-radiating electromagnetic field, whose pattern moves at exactly the particle's speed, but in a medium with lower ...
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How is Alcubierre's warp drive propeled forward?
What is the exact mechanism of the warp drive that propels it forward? I know that it creates negative pressure behind it and a positive pressure in front of it but how does this actually propels it ...
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Could reducing entanglement by unitary operations allow for FTL-communication? (and why not?)
About the closure: This Question is about why manipulating 1 particle of an entangled pair unitarily can’t cause measurable consequences on the other and how this manifests in the concretely described ...
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Does relative motion allow for speeds $>c$?
If motion is relative, (so if X was stationary and Y was moving at v m/s, we could think of this as Y being stationary and X moving at -v m/s), could we not create a scenario in which a stationary ...
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Can a non-local theory be consistent with special relativity?
If there was a non-local theory that explained quantum entanglement correlations, does it follow that it would violate special relativity?
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Can the velocity of an image produced by a plane mirror be greater than that of light?
We are currently studying ray optics in school and it made me wonder if the velocity of an image produced by a plane mirror can theoretically be greater than that of light.
Using the relation $v_i = 2 ...
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Does the no signalling theorem in quantum mechanics beg the question?
I had always thought similarly and then came across a paper here that argues this.
The abstract is as follows:
Many authors state that quantum nonlocality could not involve any controllable ...
