Recent content by AishaGirl

What I don't understand about the universe is empty space must be made of some kind of material or substance because stars and other large bodies, in fact anything with mass can bend space then it must be made of something which has the capability to bend and be distorted. How can space bend if...

Hello, AQA is a British exam board and on their paper they have a list of equations. Can someone tell me why the time dilation equation is to the power -1/2? Thanks.

OK thanks :)

Thanks for your replies. The point I'm making though is the laws of physics don't change with velocity right? So large gravitational bodies form spheres (or close to spherical) but according to an observer who is moving very fast, Earth would not be spherical, it would be flat. If the observe...

If everything is relative to something else, who's frame of reference is actually correct? For example an observer moving at 99.9%c will use the exact same laws of physics we use and determine without any doubt whatsoever that Earth is flat... flat as a pancake! So who's frame of reference is...

Thanks for the replies. So using (mc,0,0,0) is just as valid as using (mc^2,0,0,0) ?

The 4-momenta before a photon collides with a stationary election P_m=(mc^2,0,0,0) or is it P_m=(mc,0,0,0) Which is the difference between the two? Thanks.

OK thanks. So just the clarify if the probe continued its velocity of 0.8c away from Earth its wavelength will remain redshifted to an observer?

Yeah sure if it changes speed or direction then I would expect to see some change in its wavelength but there is no mention of this in the question... If the probe fell into orbit around a planet or something and its velocity was significantly reduced then I'd agree it might balance out. *EDIT*...

Homework Statement A probe is launched with velocity v=0.8c. A beacon emits a light with wavelength \lambda=500nm in its rest frame. Years later the probe is located by NASA using a telescope, When they measure the light they find the wavelength \lambda=500nm in their rest frame. Is this...