# relativity

1. ### Does QM contradict relativity?

I understand Einstein believed that no information could travel between two points at greater than the speed of light. However we know from QM entanglement that quantum attributes, not determined by hidden local variables, of spatially separated entangled twin particles have attributes that...
2. ### regarding the length contraction and time dilation in special theory of relativity

Respected Sir, as i read in relativity, some writer use inverse Lorentz's transformations equations and some other use Lorentz's transformations for solving length contraction and time dilation expressions with any logic that which one used in which situation. clear me this. with regards vikas
3. ### special relativity and a reflection paradox

The law of reflection as stated on farside is: Now, before getting to my question, suppose I use a non relativistic example first. If I have a spherical mirror and have a light source "dead centre" of the mirror then any light rays hit the mirror at perpendicular angle to the surface of the...
4. ### Acceleration in Special Relativity

Hi :) I'm working on how to resolve the twin paradox in special relativity for my 4th-year dissertation. I've found several different equations which supposedly allow for the calculation of the time experienced by each twin at set distance intervals from Earth, but they don't seem to work during...
5. ### Special Relativity effects; real or imaginary?

Clock A is at rest in space. Clock B is traveling at a uniform velocity 0.5C relative to A and is heading directly towards A. As B passes A the clocks are synchronised. A notes the distance B has travelled after one year is 0.5 light years. Question: From B's perspective... 1. how...
6. ### Example relativity

When E=m*c^2 1) Root(c^2)=c=Root(E/m) 2) 3*c*Root(c^2)=3*c*Root(E/m)=3*c^2 From 1) to 2) as an example, As velocity is faster, mass is increased. It means when velocity is increased, sec(time) is slower, and m(distance) is increased.
7. ### Light Waves And Time

PHYSICS OF OPTICS AND TIME Any correction, different point of view and criticism will be appreciated please. ABSTRACT: A brief proposition on the nature of light waves and how it affects the measurement of observers. For example: Imagine a stationary observer who is at a distance D...

Two astronauts in space compress a lightweight spring. After using it to fling themselves apart, they measure and agree their relative speed. Using special relativity, each astronaut calculates that the other's mass has increased by a millionth. But the rest mass of one was twice that of the...
9. ### question about relativity and frame of references

1:why velocity is relative but acceleration is absolute . 2:what do we mean by the term "absolute" in kinematics? 3:can we find centripetal and centrifugal force simultaneously in non inertial frame of reference ?
10. ### Physics Of Optics And Time

PHYSICS OF OPTICS AND TIME Any corrections, different point of view and criticism will be appreciated pls. ABSTRACT: A brief proposition on the nature of light waves and how it affects the measurement of observers. For example, when a disturbance is created in the waves of light due to the...
11. ### Examples of Einstein's Theory of Relativity

Einstein's theory of Relativity introduces three concepts..... Space contracts and time dilates Space time Invariant light speed I know that the space travelling twin sibling is an example of time dilation.........Can anyone of you give examples of other concepts and explain...
12. ### No gravity in special relativity

Hello, I've been looking for some solid treatment of why special relativity doesn't work with gravity. However, I was unable to find any literature regarding this topic. I know that STR deals with inertial frames and in GTR it is possible (under certain circumstances) to work in a local...
13. ### Relativity problem

1. A clock C is at rest at the spatial origin of an inertial frame S. A second clock C′ is at rest at the spatial origin of an inertial frame S′ moving with constant speed u relative to S. The clocks read t = t′ = 0 when the two spatial origins coincide. When C′ reads t′ 2 it receives a radio...
14. ### The line of object for relativity

When the line is longer, it means the measurement is increased. So when the line of object is shorter, it is decreased. So when the line is smaller, it goes to zero to be disappeared. But the line cannot disappear truly to zero as there is no Black hole.(But someday as eschatology) It means...
15. ### Quantum Mechanics and General Relativity

As someone who is in high school and hence not entirely educated in the methods of doing theoretical physics (but highly interested)... what parts specifically of quantum mechanics and general relativity need to be combined? Is it just a matter of incorporating probability into relativity (and...
16. ### Gravitation relativity

Two objects strike together, and when the velocity is higher, it hurts my body more pain. So the mass is increased. Same feeling. When two objects are closed together, when the velocity is higher, two objects meet more stronger and it means gravitation is increased. So when the mass is bigger...
17. ### Relativity - laboratory reference frame

Hi everyone, I'm new in here and I need some help to figure out this problem. A cosmic ray travels at a velocity v = 0.999c. The estimated life span in it's own frame reference is T = 1,22 * 10^-6 s Using the laboratory reference frame, how can I calculate the the average life span of the...
18. ### Relativity Question?

Can someone explain to me why an acceleration object won't eventual become a black whole? As it gains more and more relativistic mass, shouldn't an object become smaller than its own Schwarzschild radius and make light unescapable? And as a side question, does light have its own gravity? It does...
19. ### How come photons travel at the speed of light?

Sounds like a silly question but hear me out. A photon has energy, right? And isn't energy equivalent to mass? An object with mass cannot travel at the speed of light. However a photon (being a quanta of light) can travel at the speed of light. How is this possible due to mass-energy...
20. ### A probably stupid question.

I've got a fairly new founded interest in Relativity, so although I'm keen I know very little. Therefore this is probably an excruciatingly obvious question, but... Imagine that two objects are fired past each other, each at a fraction of the speed of light higher than a half - let's say...