# Linked Questions

8answers
3k views

### Interval preserving transformations are linear in special relativity

In almost all proofs I've seen of the Lorentz transformations one starts on the assumption that the required transformations are linear. I'm wondering if there is a way to prove the linearity: Prove ...
4answers
3k views

### How can we show that the speed of light is really constant in all reference frames?

I had a debate with a friend who cannot believe that the speed of light is constant. He said something like: so what if in the Michelson-experiment the moving apparatus simply added a constant ...
3answers
4k views

### Einstein's first postulate implies the second?

Einstein's two postulates of special relativity are as follows, 1. The principle of relativity: The laws of physics are the same in all inertial systems. There is no way to detect absolute motion,...
5answers
721 views

### How do we know that time dilation applies to objects other than light?

Here is a traditional derivation of time dilation: There's a train with a lamp in the ceiling, moving at velocity v with respect to an observer. In the frame of the observer, the path taken by the ...
4answers
1k views

### Postulate implies existence Lorentz transformation?

My textbook about Special Relativity says that the existence of Lorentz Transformation is guaranteed by the postulates of Special Relativity. So, I'm assuming it's the first postulate we're talking ...
1answer
507 views

### What is physical meaning of Lorentz boost?

Physical meaning of spatial part of Lorentz transform is, obviously, rotations in R-space. Does anybody have a nice physical interpretation of boosts though? I can understand to some extent off-...
1answer
185 views

### How to motivate this approach on Special Relativity?

One of the most common approaches to Special Relativity is that based on the two Einstein's postulates: The laws of Physics are invariant in every inertial reference frame The speed of light ...
1answer
130 views

### Invariance of spacetime interval in special relativity: linearity

I'm trying to understand which assumption are necessary to prove the invariance of the spacetime interval $$\Delta s^2=c^2\Delta t^2-\Delta \mathbf{x}^2$$ in special relativity. The postulates of ...
1answer
98 views

### Explanation and derivation of Lorentz equations

I've read about special relativity recently and I've learned about the Lorentz transformation. I get what time dilation and length contraction are and I think I understand what the transformation does ...
0answers
53 views

### Lorentz transformation, non linear space transformations [duplicate]

The Lorentz transformation is linear in $x,y,z,t$. Are there are any non linear space transformations that leaves the speed of light constant in all inertial frames? The possibility being that space ...
0answers
46 views

### Is the linearity of transformation of intervals postulate in SR? [duplicate]

Let $O$ and $\overline{O}$ be inertial frames, $A$ and $B$ be events, the interval between $A$ and $B$ be $(\Delta t, \Delta x, \Delta y, \Delta z)$ in $O$ and \$(\overline{\Delta t}, \overline{\Delta ...