# Questions tagged [special-relativity]

The special theory of relativity describes the motion and dynamics of objects moving at significant fractions of the speed of light.

5,797 questions
88 views

### Finding the expression for probability density (the Klein Gordon equation)

Source: Quantum Field Theory for the Gifted Amateur by Tom Lancaster, Stephen J. Blundell. I am struggling to understand the logical step from the outline of the 'proof' in the footnote, to the fact ...
45 views

### What does the photon feel when it hits an asteroid on its path to earth [duplicate]

If a photon was approaching earth, after 1 minute(from earths reference frame) an asteroid comes on the photons path. And it hits the asteroid, but from the photons reference frame time doesn't pass ...
17 views

### What's a good book about tensors? Also when to learn special relativity using tensors? [duplicate]

I've tried learning basic tensor calculus (transformation law, inner & outer products, adding , etc..) and I could 'work' with the math with no problem, but sometimes I couldn't quite understand ...
49 views

### Deriving Doppler effect in observer's frame

I am attempting to find the Doppler factor from the frame of the observer. In the frame of the observer, the source is moving at velocity $v$ towards the observer. Since the source emits at time ...
72 views

### Books, papers, etc on Lorentz and Poincare groups/algebras/etc

I'm currently trying to learn more about the Lorentz- and Poincare Lie-algebras and the representation theory about them. But I'm really struggling with the material that we were given and I'm also ...
50 views

### Pole in the barn paradox [duplicate]

I was reading Schutz relativity when I came across the barn-pole paradox. I have seen many videos and explanations on the internet including Minkowski diagrams but I don't seem to understand it enough ...
57 views

### Energy and mass at absolute zero temperature

Hi my question is if the temperature of a particle is reduced to absolute zero the that particle has lost its energy so it has no movement. Particles have mass and Einstein said mass equates to energy....
74 views

### Duration of a accelerated movement in special relativity

Consider a point $P$ which does the following (one dimensional) movement: Uniform acceleration $a_0$ (proper aceleration) from $t=0$ to $t=T$ (time measured in lab's frame). Uniform deceleration $a_0$...
70 views

64 views

### Relativity from a basic assumption

Is it possible to derive Lorentz transformations just by assuming that if two spaceships are moving away from each other with a constant speed, it is impossible for them to tell who is moving, even if ...
34 views

### Looking back in past [closed]

Can faster than light communication give us the ability to see in the past, that is to say, if we can imagine a ultra huge highly advance telescope 60 light minutes away from earth and we want to look ...
36 views

### Equivalence in all inertial frames

Suppose there is a train moving to the right. and inside the train there is an observer, A. Outside the track, there is another observer B. When the train passes in front of B, right at the instant ...
27 views

### Constant acceleration space travel: velocity relative to the Earth? [duplicate]

Suppose we are in a spacecraft that is moving away from the Earth along a straight line with a constant acceleration of $1G$, and that this acceleration can be sustained indefinitely. Accelerating at ...
67 views

### How can we justify time dilation if we look through an spyglass at Einstein's light clock?

Assume that a space shuttle travels in a circular path having a radius $r_s$ at a tangential speed $v_s$ - a considerable fraction of the speed of light. There is a light clock inside the shuttle ...
257 views

### What is the spin-statistics theorem in higher dimensions?

In $d = 3+1$ dimensions, the spin-statistics theorem states that fermionic particles have half-integer spin and bosonic particles have integer spin, in a well-behaved relativistic quantum field theory....
59 views

### When we burn a match stick it did not go at $c$ speed, why?

When we burn a match stick then mass is converting into energy then according to the relativity match stick particles should go at speed of light but it did not happen why