All Questions
Tagged with faster-than-light tachyon
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Two-way tachyonic anti-telephone
Consider the two-way tachyonic antitelephone where the speed at which message is transmitted is $a$. A person $A$ sends a message to $B$ which is moving away with a speed of $v$ with respect to $A$. ...
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One-way Tachyonic anti-telephone
When you have length contraction in special relativity
$$L' = L/\gamma$$ the interpretation is that $L'$ is the length of an object with rest-length $L$ moving with respect to an observer at rest. ...
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What is innermost unstable circular orbit (IUCO)?
In the paper Tachyon motion in a black hole gravitational field by V. M. Lipunov he writes:
(…) Circular orbits for tachyons begin at the distance of $ 3/2~r_g $, i.e., at the distance of the ...
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Why do we assume that we can change the past by sending signals backwards in time? [closed]
This might be a stupid question, but hang in with me-
From what I've seen, the biggest argument against superluminal signaling is that you would be able to send a message backwards in time that could ...
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Does the tachyonic antitelephone actually show a time-travel paradox? [duplicate]
The tachyonic antitelephone paradox is, roughly, this:
Alice is in a space station and watches Bob go past at relativistic speed in a spaceship. Some time later she sends him a message at ...
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Tachyon velocity in relation to light speed [duplicate]
tachyonic particle are merely hypothetical particle that always travels faster than light., But if real, how fast would they be?
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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.
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Imaginary Lorentz factor in special relativity [duplicate]
This thing is making me confuse, what is mean by imaginary Lorentz factor in Physics? What is the physical meaning of imaginary?
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Some help in understanding energy conservation relating to special relativity
Consider the decay of particle $A$ into particles $B$ and $T$ where $T$ is the tachyon particle. The conservation of energy equation can thus be expressed as
$$m_A=\sqrt{p^2+m^2_B}-\sqrt{p^2-m^2_T}\,.$...
user161157
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Velocity addition for tachyons
How does the velocity of a tachyon transform under a Lorentz boost? Suppose we only consider motion along the $x$ direction for simplicity. If the velocity of the tachyon is $u$ in the lab frame, what ...
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Can a particle with non-zero rest mass "tunnel" into the tachyon world without having to cross the $m=\infty$ barrier?
In the above diagram, I've indicated the variation of mass of a particle with its velocity using the solid curve for $v < c$ and using the long dashed lines (which lie in the complex plane) for $v &...
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Tachyons as vector representations on the surfaces transitivity of Lorentz group?
In Wikipedia's surfaces of transitivity (of Lorentz group $G$, it says
"Standard vectors on the one-sheeted hyperbolas would correspond to tachyons. Particles on the light cone are photons, and ...
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Are a tachyonic particle a mathematical impossibility (not just physical)?
I recently learned from a helpful SE user that, in general relativity, the "law of geodesic motion" is actually a mathematical law, not a physical one. That is, a "test particle" (...
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Collision of hypothetical Tachyon with normal particle?
If we are dealing in one dimension, what will happen if a hypothetical particle Tachyon (pure imaginary rest mass, $v>c$ and real momentum & total relativistic energy)? Will it interact with ...
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Why is the square of the neutrino mass negative?
Why is the square of the neutrino mass negative?
In arXiv:hep-ph/0009291 this is explained by giving the example of:
$$m^2_{\nu_e}= -2.5 \pm 3.3 \text{eV}^2 \tag{1}$$
"Thee negative value of the ...
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