Thread: Red shift

Sorry.

Basically if x is proportional to y then you write y = k*x where k is constant. If you double x then y doubles.

Force is proportional to the thing that causes force. In the case of two particles applying a force to each other, it's proportional to the force-causing aspect of both of them, so F = k*x1*x2; if you double either force-causing aspects, the force doubles. Also it's proportional to 1/r^2, so if you double the distance between the particles, the force divides by 2^2 = 4.

Makes more sense..?

Originally Posted by Xei

Sorry.

Basically if x is proportional to y then you write y = k*x where k is constant. If you double x then y doubles.

Force is proportional to the thing that causes force. In the case of two particles applying a force to each other, it's proportional to the force-causing aspect of both of them, so F = k*x1*x2; if you double either force-causing aspects, the force doubles. Also it's proportional to 1/r^2, so if you double the distance between the particles, the force divides by 2^2 = 4.

Makes more sense..?

Yea, it makes a bit more sense. I just don't see where this comes into red shift or big bang.

It doesn't really, I was just responding to post 4.

The easiest way to think about red shift is that, as a light emmiting body moves away from you, the distance between the peaks of the light waves increases compared to what they would be if the body was still, and therefore the light has a longer wavelenth; i.e. it is shifted towards the red end of the spectrum.

Oh right, cool.

And thanks, that makes sense.

Wait a minute.

I just realised something. Where the heck does the energy come from for the acceleration to happen? I know this is what Philosopher said kinda, but are there any theories on that?

Or... is that to do with negative pressure?

Originally Posted by slash112

Wait a minute.

I just realised something. Where the heck does the energy come from for the acceleration to happen? I know this is what Philosopher said kinda, but are there any theories on that?

Or... is that to do with negative pressure?

What acceleration? The acceleration that we see today is the reason that we postulate dark energy. The change to gravity that I was talking about is all about making dark energy disappear since it's never been observed. The reason that this ties into the big bang is that various ways of explaining dark energy also explain cosmic inflation that occurred after the big bang.

read here for stuff about the big bang.

Originally Posted by PhilosopherStoned

What acceleration?

Originally Posted by PhilosopherStoned

The acceleration that we see today.

Ok, how come you didn't know what acceleration i was talking about, then go on about the acceleration.

(just to be clear, I was talking about the acceleration of the expansion)

And you answered my question, so thanks.