Recent content by Paul77

Rapidities are a clever way of representing this but when I first came across this article I made the assumption that c could not be exceeded because of how the maths works but then I watched a derivation of the lorentz transforms and realized that the 'fundemental' reason is that c is assumed...

Have been reading the "Impossibility of exceeding c" notes in the Lorentz Transformation physics forum page: www.physicsforums.com/library.php?do=view_item&itemid=19 Where it states: "It is often said that nothing can be accelerated to the speed of light because its mass increases as...

Thanks I forgot about the effect of the motion of the Earth on the vertical path and hence there is a path length difference for the vertical compared with the horizontal. I found this video on youtube which calculates the time difference between the two paths and expected fringe shift - which...

The Michelson Moorley experiment to detect the presence of aether is the main experiment that gave rise to the theory of relativity. I've been trying to understand this experiment. The idea of the experiment was to split a beam of light and then align one the split beams with the aether and...

ok thanks I'll take a look they seem cheap enough I take it that the QED: The Strange Theory of Light and Matter book also covers this subject - a book rather the lecture transcript might be more accessible.

Have found a Youtube video: The Reason for Antiparticles: The 1986 Dirac Memorial Lecture Other than the book of the lecture, which is difficult to get hold of cheaply, does anyone know if this material on why quantum mechanics and relativity together require the existence of antiparticles...

I meant "move through spacetime". I think its true because its a quote from one of the main PF contributors.

I've been informed that when you move through spacetime: If you move through time with the same space-time curvature, your effective "speed" through time is c. Does anyone have a link that explains this?

Re: your example of two spacecraft - I'm aware of the idea of special relativity - but mainly I've been interested in how the theory originated. So I've read up on the Kennedy-Thorndike experiment, frames of reference, lorentz transformation, rapidities, how rapidity is a tanh and therefore...

I got the notion from the idea that if time dilates then spacetime dilates and so spacetime is warping, if you sum the warps you would get curved spacetime over a larger area and objects will follow the curves in spacetime which gives the illusion of gravity. Agreed its a test of special...

Because if time dilates in an event being observer then has’nt the time component of spacetime dilated? To get a better understanding of time dilation have looked at the Kennedy-Thorndike experiment - one of the first experiments to demonstate time-dilation. My understanding of this is...

Is'nt that the general idea? The proton beams in a collider can't reach the speed of light can they?

I'm still digesting all the other posts but wrt: "You have cause and effect backwards. Time dilation does not cause gravity; it is gravitation that causes time dilation" Have I really got this wrong as well! I thought that relativity is based on the idea that there is no absolute frame of...

Re: Another way to think of it: I'm sure your right but I don't see why you have to scale time by the speed of light. "and c 1s = 3E8m in time" is that "and c x 1s = 3E8m in time"

Presumably R is from the middle of the Earth's to say the satellite - since in space you are in zero gravity. So the spacetime curveture is very slight and I would'nt expect a ball to roll down it. I don't see why the speed of light needs to be introduced - the Earth may be moving very fast in...