Is My Time Dilation Equation Correct?

[svijay1991]

try this. get on to the top of a tall building and flash a light downwards. According to you the light ray must be deviated and should not hit the target (because Earth is moving around sun, 30 Km/s which is moving around the galaxy, 220 Km/s which is in turn moving at a very high speed from other galaxies) but it will.

so can we say we are moving at very high speed that is 99.99% of light speed?

 

[ghwellsjr]

so can we say we are moving at very high speed that is 99.99% of light speed?

Yes, you could say that, if you pick a reference frame that is moving at 99.99% of light speed relative to us.

Remember, you can analyze any scenario from any reference frame you choose, none is preferred over any other, even the one in which we are at rest. That's the whole point of Special Relativity.

 

[zonde]

i meant this. but i don't understand why do you think a laser won't work

Then I would say that this is just misunderstanding. I didn't say that laser won't work (at least I didn't mean that). I tried to propose some change in the setup just to get from dead spot in discussion.

I think that saying that the person is stupid and he has to think harder to get what is told him might not work if his misunderstanding is actually not addressed. So introducing some changes in setup might bring up the problem.

 

[svijay1991]

EDIT: Look, you clearly don't "get" this stuff. It's been explained to you several times now. If you really want to learn what's going on, you need to stop thinking that the explanations are wrong and start trying to understand why they are correct.

Thank u phinds

I was thinking, why those explanation are correct. But still i cannot understand the thing.
Iis there any practical example or application for time dilation.?

 

[svijay1991]

try this. get on to the top of a tall building and flash a light downwards. According to you the light ray must be deviated and should not hit the target (because Earth is moving around sun, 30 Km/s which is moving around the galaxy, 220 Km/s which is in turn moving at a very high speed from other galaxies) but it will.

Ya i know that because it is comparatively very less distan.(matter of 1 km)
but speed of light is 3lakh km/s. Even if it deviates we cannot see the deviation .

 

[svijay1991]

Yes, you could say that, if you pick a reference frame that is moving at 99.99% of light speed relative to us.

Remember, you can analyze any scenario from any reference frame you choose, none is preferred over any other, even the one in which we are at rest. That's the whole point of Special Relativity.

As you said, if u consider a reference frame which is moving at 99.99% of light speed relative to us has one observer in it.
Then the observer (in moving frame of reference) will feel our's time is dilating ... Am i right ..?

it is same for us also

because if we consider us as the reference frame, we can say that the observer is moving at 99.99% of light speed. So we will feel his time is dilating .


So time dilation seems to be illusion..

I know no one will agree this . But try to think in my point of view.

 

[Michael C]

is there any practical example or application for time dilation.?

GPS navigation systems.

 

[ghwellsjr]

Yes, you could say that, if you pick a reference frame that is moving at 99.99% of light speed relative to us.

Remember, you can analyze any scenario from any reference frame you choose, none is preferred over any other, even the one in which we are at rest. That's the whole point of Special Relativity.

As you said, if u consider a reference frame which is moving at 99.99% of light speed relative to us has one observer in it.
Then the observer (in moving frame of reference) will feel our's time is dilating ... Am i right ..?

it is same for us also

because if we consider us as the reference frame, we can say that the observer is moving at 99.99% of light speed. So we will feel his time is dilating .


So time dilation seems to be illusion..

I know no one will agree this . But try to think in my point of view.

Following your logic: motion seems to be an illusion. Is that your point of view?

 

[phinds]

Thank u phinds

I was thinking, why those explanation are correct. But still i cannot understand the thing.
Iis there any practical example or application for time dilation.?

As MichaelC said, the most obvious practical use is GPS. Do you like driving in the forest or actually on the road? I prefer the road. Fewer trees to run into. If my GPS didn't understand time dilation, I would be driving in the forests.

 

[svijay1991]

Following your logic: motion seems to be an illusion. Is that your point of view?

No. We cannot say whether the body is moving or not until we compare it with some other.

So the time is appear to be dilated for both stationary and moving observer by considering the cases i have mentioned earlier.

If time dilation is also relative(as motion) there will be no absolute time dilation.

This is what my point of view

 

[Naty1]

If time dilation is also relative(as motion) there will be no absolute time dilation.

To measure time dilation, bring clocks to the same worldline...that is the same place and time
and compare.

Note that relative velocity AND gravitational potential EACH cause time dilation.

 

[Naty1]

But try to think in my point of view.

Why?
I'd consider it if you view led to some new valid insight; otherwise it seems pointless.

 

[svijay1991]

Why?
I'd consider it if you view led to some new valid insight; otherwise it seems pointless.

You meant to say, it is pointless

 

[ghwellsjr]

Following your logic: motion seems to be an illusion. Is that your point of view?

No. We cannot say whether the body is moving or not until we compare it with some other.

So the time is appear to be dilated for both stationary and moving observer by considering the cases i have mentioned earlier.

If time dilation is also relative(as motion) there will be no absolute time dilation.

This is what my point of view

As long as motion is inertial (no acceleration, no change in speed, no change in direction), then time dilation is also relative. But, like motion, if one of the bodies makes any of those kinds of changes, then there is a difference between the two bodies and we can make some absolute statements regarding their motions, can't we?

For example, if both bodies start out at rest with respect to each other, we can consider them to be motionless relative to each other. Then if just one of them accelerates, taking a trip at a high speed and returning to the other body and coming to rest with respect to it, we can absolutely say that the motions of the two bodies is different, can't we? In the same way, we can say that the time dilation is different for the two bodies, can't we?

 

[svijay1991]

As long as motion is inertial (no acceleration, no change in speed, no change in direction), then time dilation is also relative. But, like motion, if one of the bodies makes any of those kinds of changes, then there is a difference between the two bodies and we can make some absolute statements regarding their motions, can't we?

For example, if both bodies start out at rest with respect to each other, we can consider them to be motionless relative to each other. Then if just one of them accelerates, taking a trip at a high speed and returning to the other body and coming to rest with respect to it, we can absolutely say that the motions of the two bodies is different, can't we? In the same way, we can say that the time dilation is different for the two bodies, can't we?

In your case we can say the motion of two bodies is different but we cannot say about its absolute motion because still it is relative . That is we know, among the two bodies one is moving (or accelerates) but, we cannot say which one is moving. It will be always relative irrespective of its motion type.

 

[ghwellsjr]

As long as motion is inertial (no acceleration, no change in speed, no change in direction), then time dilation is also relative. But, like motion, if one of the bodies makes any of those kinds of changes, then there is a difference between the two bodies and we can make some absolute statements regarding their motions, can't we?

For example, if both bodies start out at rest with respect to each other, we can consider them to be motionless relative to each other. Then if just one of them accelerates, taking a trip at a high speed and returning to the other body and coming to rest with respect to it, we can absolutely say that the motions of the two bodies is different, can't we? In the same way, we can say that the time dilation is different for the two bodies, can't we?

In your case we can say the motion of two bodies is different but we cannot say about its absolute motion because still it is relative . That is we know, among the two bodies one is moving (or accelerates) but, we cannot say which one is moving. It will be always relative irrespective of its motion type.

Are you saying that because one of the bodies accelerated, we can't say which one it is?

 

[Passionflower]

In your case we can say the motion of two bodies is different but we cannot say about its absolute motion because still it is relative.

Nope, the inertial and accelerating observer will observe a different Doppler pattern coming from the other observer. Both can determine which accelerated even if they do not have an accelerometer.

 

[svijay1991]

Nope, the inertial and accelerating observer will observe a different Doppler pattern coming from the other observer. Both can determine which accelerated even if they do not have an accelerometer.

Ya now i agree with u. If the bodies undergoes uniform motion then can we able to distinguish the motion of the bodies.?

 

[svijay1991]

Are you saying that because one of the bodies accelerated, we can't say which one it is?

Sorry george i made mistake there. I agree with u. We can distinguish motion in that case

 

[ghwellsjr]

Ya now i agree with u. If the bodies undergoes uniform motion then can we able to distinguish the motion of the bodies.?

For two bodies that never experience any acceleration, we can only assign relative motion between them which means there is no way to compare their clocks as all frames will have different definitions of their relative times.

Sorry george i made mistake there. I agree with u. We can distinguish motion in that case

In that case, when one of the bodies accelerates away from the one that remained inertial, all frames will agree on the difference in the amount that their two clocks progress during the time they were separated.

In fact, as long as two bodies start out together and both accelerate in any manner and then rejoin at the same location or any other location, all frames will agree on the difference in the amount that their two clocks progress during the time they were separated.

How could it be otherwise?

 

[svijay1991]

here's a simple one with graphics:

http://www.phinds.com/time%20dilation/

hello phinds

I have attached one picture to this and i tried to derive equation for time dilation from that.
please see and tell whether it is right or not ?

 

[phinds]

hello phinds

I have attached one picture to this and i tried to derive equation for time dilation from that.
please see and tell whether it is right or not ?

Looks right to me, and not surprizing, since it's the standard formula although I think it's normally expressed in terms of T, not in terms of t