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Questions tagged [tachyon]

Tachyons are hypothetical particles with imaginary mass and they thus may move faster than light. However, their existence in a theory, indicates an unstable ground state.

s are hypothetical particles with imaginary mass and they thus may move faster than light. However, their existence in a theory, indicates an unstable ground state, due to the Sen Conjecture. They violate .

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How does faster than light travel violate causality?

Let's say I have two planets that are one hundred thousand lightyears away from each other. I and my immortal friend on the other planet want to communicate, with a strong laser and a tachyon communication device. I record a message on the tachyon…
markovchain
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Status of experimental searches for tachyons?

Now that the dust has settled on the 2011 superluminal neutrino debacle at OPERA, I'm interested in understanding the current status of experimental searches for tachyons. Although the OPERA claim was a fun puzzle for theorists trying to find…
user4552
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Do tachyons move faster than light?

I am trying to understand whether or not tachyons travel faster than light. The linked Wikipedia page shows some seemingly contradictory statements, and they are confusing. For instance, the first sentence states that tachyons "always travel faster…
A.R.K
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What would be the effects on theoretical physics if neutrinos go faster than light?

Earlier today, I saw this link on Facebook about neutrinos going faster than the speed of light, and of course, re-posted. Since then, a couple of my friends have gotten into a discussion about what this means (mostly about time-travel), but I don't…
El'endia Starman
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Can something travel faster than light if it has always been travelling faster than light?

I know there are zillions of questions about faster than light travel, but please hear me out. According to special relativity, it is impossible to accelerate something to the speed of light. However, we can still have objects (like photons) going…
Javier
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Spinning Tachyons

In all examples that I know, tachyons are described by scalar fields. I was wondering why you can't have a tachyon with spin 1. If this spinning tachyon were to condense to a vacuum, the vacuum wouldn't be Lorentz invariant---seems exotic but not…
truebeliever1234
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Contradictions caused by moving faster than light

There was a Joe Rogan episode with Brian Greene where Joe thinks aliens are watching us because the universe is infinite and there are an infinite number of them. So some of them must be watching. Brian says "take a 5 billion light year ball and…
Rohit Pandey
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How do tachyons violate causality?

Something moving faster than light should have imaginary mass, like photons have zero mass and thus travel at $c$. I have read this article of physicist E. C. George Sudarshan. He said taking mass to be imaginary we get real energy and momentum. (I…
Paul
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What if photons are not the fastest particles?

Einstein originally thought that special relativity was about light and how it always travelled at the same speed. Nowadays, we think that special relativity is about the idea that there is some universal speed limit on the transfer of information…
user132181
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Tachyons and Photons

Is there a particle called a "tachyon" that can travel faster than light? If so, would Einstein's relativity be wrong? According to Einstein no particle can travel faster than light.
einsteinlover
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Can tachyons escape the gravitational pull of a classical black hole?

Anything that crosses the event horizon of a black hole cannot escape the pull since it has crossed the Schwarzschild radius and thus, the escape velocity is greater than the speed of light, and since "nothing can travel faster than the speed of…
Investor
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Would the horizon of a black hole be different for a tachyon than for subluminal matter or photons?

One of the most useful black hole analogies I've seen imagines that space is "flowing" like a river into a black hole, and the point at which it flows in faster than c is the horizon. This analogy leads to the idea that a tachyon could escape from…
Richardbernstein
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Does Einstein’s original paper on relativity predict antiparticles and tachyons?

In Einstein’s original paper on relativity (pages refer to this copy) page 149 he gets an initial form of the now known as Lorentz transformation $$\mathbf{x’}=\phi(v) \Lambda \mathbf{x} \tag{1}$$ (I used current matrix representation as the lazy…
J. Manuel
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Why does tachyon arise in bosonic string theory?

I am looking for precise mathematical and physical reasons which cause the presence of tachyon in bosonic string theory(specially closed bosonic string theory). Has it to do with the specific form of the conformal field theory of free bosons? In…
user10001
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Are Electromagnetic Waves The Only Means of Transmitting Information?

We've been using EMF to transmit energy (information) for over a century. I was wondering is there any other way to send a message on long distances, even faster than EMF waves can travel? For example there are particles that travel faster than C.…
behnam mohammadi
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