Recent content by nemosum

I agree with mmarko. And besides, the whole point of physics is to determine how the universe works, through experimentation etc. You can't experiment with something that is not physical, therefore trying to do so gets you no where really fast.

OK, thanks.

Lets say that there is a man flying in a spaceship going fast enough that to another observer standing on the Earth he appears to be twice as big as normal due to relativistic mass (I might be wrong here, and relativistic mass doesn't make you look bigger). From the man's frame he would say he...

lol, It's a little hard to let go of "absolute" perspectives and values. Thanks for the feedback! nemo

OK, here's another question: Using the same example EL did, the spaceship flying from the west would observe the spaceship coming from the east as having more relativistic mass than the observer on the ground would right? And the spaceship from the east would see the same thing with the one...

Thanks EL, you interpreted my question right, I think I understand now. I was about to post an example just like that, but I guess I don't need to. nemo

When you calculate the relative velocity of two bodies moving towards each other at almost c, are you calculating the observed relative velocity, or the actually relative velocity. Because if it's the actual velocity then technically no body could ever move faster the 1/2c due to the fact that...

Yeah, that's what I meant, I was just making sure that was the case. But appearently I didn't state it very well. So here's a question, jtBell gave another more general equation: x^\prime-x\prime_0=\gamma[(x-x_0)-v(t-t_0)] t^\prime-t\prime_0=\gamma[(t-t_0)-v(x-x_0)/c^2] but...

So if we were trying to derive x' from x values then it would still basically come out as x+vt rather than x-vt because the ground observer is traveling in a negative direction relative to the view of the high-jumper. OK, that makes sense. So in the case that we have here the numerator for...

OK, so now I have some questions about plugging in the numbers. First of all, why can't we just assign t' to the person on the ground and t to the high-jumper? Thus wouldn't the numbers come out different? Because you would have all negative signs? And second question: if t and t' must always...

I'm reading Einstein's "Relativity, the Special and General Theory" And it just talked about the Lorentz transformations, but I don't quite understand what it's used for. I understand how the time dilation and length contraction equations are derived from it but I don't understand how to use the...

I think Mortimer has a point. Picture space-time as the classic rubber sheet. if you drop a bowling ball in the middle the sheet will bend down, representing gravity caused by a large body of mass. Likewise we can picture this body of imaginary mass as a bowling ball being shoved up from...

In another thread someone posted a scenario in which as light-year long wall travels at a certain percentage of the speed of light so that it contracts to 1 foot. If you looked at the wall as it went past would you see it as a foot, or a light-year long?

Do we know exactly what would happen to an objects rest mass is it reached the speed of light? And does relativistic mass make an object look bigger?

I didn't have the time to look through that whole link, so I was wondering if anyone could give a quick definition (not too technical please) of Gavitational Potential Energy.