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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Why the phase velocity of X-rays inside glass is faster than $c$?
For hard X-rays the refraction index of glass becomes slightly $n<1$ which means that the phase velocity (not group velocity) of X-rays inside glass is larger than $c$ the group velocity speed ...
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Could information be transferred through a wormhole?
There was a paper published recently about the possibility of sending messages through a wormhole,see reference here. It has also been speculated that any entangled pair of particles—even particles ...
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Will this hypothetical circular singularity FTL travel warp drive work? [closed]
Not a physicist, but just wanted to know if this would work in theory:
Since nothing can practically travel faster than the speed of light (for now until proven otherwise), the only way for ...
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Is it possible to have a medium rarer than vacuum? [duplicate]
I was wondering whether it is possible to have a medium rarer than vacuum. If that is possible then we can increase the speed of light beyond $c$. Might sound like a weird question.
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Lorentz transform causes Faster than light motion for Spacelike-separated object?
Consider a 5-meter rod which exists on the x-axis of a frame of reference:
Now consider an observer moving at a velocity $0.1c$ relative to this reference frame, from right to left. Their frame of ...
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What would happen if two super-massive black holes collide faster than the speed of light? [closed]
I know objects can't move through space faster than light. But there's no law against the expansion of the universe increasing the distance between two objects faster than the speed of light. But this ...
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Is it possible to know if an entangled particle's state is a superposition or collapsed? [duplicate]
I understand it's not possible to transmit information using entangled particles due to the randomness of the measure results.
But what if the act of measuring itself IS the information?
Let's say ...
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FTL Communication using Quantum Entanglement (A new Approach) [closed]
Ok i have a proposition:
Imagine there are two people 1 on earth and other in space.
They syncronised their clocks before they left earth and agreed that they will factor in time dilation and ...
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Speed of light getting lower in densed medium [duplicate]
In densed medium speed of the light gets lower so in this kind of situation is there anything which can travel quicker than light?
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Communication via entanglement [duplicate]
For years now i have in my haed a thought experiment for information exchange via quantum entanglement. And i am aware that something must be wrong with it but i can't figure out what it is.
The ...
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FTL communication setup. Why wouldn't this work?
The setup is similar to quantum eraser experiments (see below). The laser pulses at regular intervals to send bunches of photons. They get split in half as entangled particles. One beam is sent 1 ...
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Instantaneous transmission of data across arbitrary distances via quantum entanglement [duplicate]
As a forward, I'm no a physicist or a student of it. In fact I'm pretty ordinary. So if I mischarecterize some concepts, bear with me.
So I was reading up on some of the new technologies and then I ...
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Faster than light communication by entangled photons [duplicate]
Faster than light communication is not possible. If I measure the polarization of an entangled photon and it turns out to be right circularly polarized. In that instant, dont I know that someone ...
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Speed of wave more than $c$
We are always told that information cannot travel faster than light (speed $c$). So, my question is, if we talk about a wave lets say a transverse wave. We can define a wave as the systematic ...
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We can't go faster than the speed of light. Can we accelerate light, then? [closed]
If there's a way to artificially accelerate light, or when it's naturally faster such as around a blackhole, then in that case, would it be possible to go past the 299792458 m / s limit?
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