SR Question

[Johnny5]

This came up in post 12 of this thread, and rather than having the topic there branch, I thought i just might move my question to another post. Here is what arose in the other thread:

 

Originally Posted by LKL

How do you know if that something is spinning or not? What

 

If Newton's laws or special relativity are seen to hold, you are not in an accelerating frame. Specific applications to do this for rotations include the Foucalt pendulum and the Sagnac interferometer.

 

Here is what i would ask you about.

 

You say that if special relativity holds then you are not in an accelerating frame.

 

Here is my question.

 

Could you run through an explanation of the time dilation formula of SR for me. Specifically, I want to see how you explain each of the letters in the formula, be they constants, or variables. I suppose I am most focused on v.

 

Dt` = Dt (1-v^2/c^2)^(-1/2)

[5614]

If you are going to ask about time dilation and accelerating frames see:

http://www.scienceforums.net/forums/showthread.php?t=11321

Post #37 & #38

 

V, velocity is a constant, only when acceleration is applied does it become a variable, velocity by itself, without the interaction of another thing (acceleration) is constant. Similar to this is a number is constant, until you do something to it e.g. add something, multiply it by something etc. The number itself is constant until something happens, similarly velocity is constant until acceleration occurs.

 

I dunno, I'm just kinda making that up as I went along, but it seems to make sense, if you see what I mean!

 

Why, what were you trying to get at?

[swansont]

t is the time measured by the observer in his own frame

t' is the time that passes in the other frame, as measured by the observer

v is the speed of the other frame with respect to the observer

c is the speed of light in vacuum

 

 

D probably means "delta" so the time variables represent intervals between two events

[Johnny5]

t is the time measured by the observer in his own frame

t' is the time that passes in the other frame' date=' as measured by the observer

v is the speed of the other frame with respect to the observer

c is the speed of light in vacuum

 

 

D probably means "delta" so the time variables represent intervals between two events[/quote']

 

Well then we are assigning all the symbols the same meaning, so why do we not agree that there is a contradiction?

 

Actually maybe not. You have c = "speed of light in vacuum"

 

What frame is c in precisely?

[Johnny5]

If you are going to ask about time dilation and accelerating frames see:

http://www.scienceforums.net/forums/showthread.php?t=11321

Post #37 & #38

 

I wasn't planning to complexify things by disscussing how SR holds up to acceleration. Right now I just wanted to see whether or not Dr Swanson claimed that V is the relative speed between two frames. He did.

[swansont]

Well then we are assigning all the symbols the same meaning' date=' so why do we not agree that there is a contradiction?

 

Actually maybe not. You have c = "speed of light in vacuum"

 

What frame is c in precisely?[/quote']

 

c is the same in any inertial frame.

 

What is the contradiction?

[Johnny5]

c is the same in any inertial frame.

 

What is the contradiction?

 

 

What do you consider to be an inertial frame?

[swansont]

What do you consider to be an inertial frame?

 

What every other physicist considers to be an inertial frame. One that has no acceleration - it's moving at a constant velocity.