# Naked Science Forum

## Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jckatz on 07/04/2017 04:33:31

Title: Would time travel faster if we stood still?
Post by: jckatz on 07/04/2017 04:33:31
the earth is orbiting the sun at 67,000 mph and the sun is orbiting the galaxy at 560,000 mph and since time is realitive to speed,  do we know how much faster time would be moving if you left earth and stopped all relative movement?

Title: Re: how much faster would time go if we stood still?
Post by: Kryptid on 07/04/2017 06:09:34
You can't, really. Another tenet of relativity is that there is no such thing as absolute motion (and by extension, no such thing as being absolutely stationary). Something that looks like it's moving while you are sitting still would see you as the one who is moving instead.
Title: Re: how much faster would time go if we stood still?
Post by: chris on 07/04/2017 07:37:58
Although the answer to this question does provide a nice explanation for the effects of speed on time:

https://www.thenakedscientists.com/forum/index.php?topic=70057.0
Title: Re: how much faster would time go if we stood still?
Post by: PmbPhy on 08/04/2017 05:28:31
You can't, really. Another tenet of relativity is that there is no such thing as absolute motion (and by extension, no such thing as being absolutely stationary). Something that looks like it's moving while you are sitting still would see you as the one who is moving instead.
That is not quite correct. Observers in orbit around the sun can tell that they're in orbit because they're in an accelerated frame of reference and such frames are not the same as inertial frames.
Title: Re: how much faster would time go if we stood still?
Post by: jckatz on 08/04/2017 06:34:55
You can't, really. Another tenet of relativity is that there is no such thing as absolute motion (and by extension, no such thing as being absolutely stationary). Something that looks like it's moving while you are sitting still would see you as the one who is moving instead.

OK, but you could still in a thought experiment decelerate an object equal to the speed of the solar systems motion and earth's motion.
Title: Re: how much faster would time go if we stood still?
Post by: PmbPhy on 08/04/2017 06:46:58
You can't, really. Another tenet of relativity is that there is no such thing as absolute motion (and by extension, no such thing as being absolutely stationary). Something that looks like it's moving while you are sitting still would see you as the one who is moving instead.

OK, but you could still in a thought experiment decelerate an object equal to the speed of the solar systems motion and earth's motion.
And your point here would be .... ?
Title: Re: Would time travel faster if we stood still?
Post by: Kryptid on 08/04/2017 16:31:11
That is not quite correct. Observers in orbit around the sun can tell that they're in orbit because they're in an accelerated frame of reference and such frames are not the same as inertial frames.

Well, yes, you can tell if you are accelerating or not. Presumably, the question intended for the observer to not be accelerating.
Title: Re: Would time travel faster if we stood still?
Post by: yor_on on 08/04/2017 18:25:30
That's a tricky one, is it not?

As Pete says we're in a accelerated frame of reference relative the sun, and possibly the galaxy too? But if you're asking whether there is a more 'correct' time setting for ones clock, then it has to be your 'proper time'. And that one will be proper at all times as far as I know:) what I mean is that your clock is your clock, and a speed or velocity is what you think yourself to have relative something else. (uniform motions that is)

nah, not the galaxy, I think?

But the sun, yeah. " According to Newton, an object will only accelerate if there is a net or unbalanced force acting upon it. The presence of an unbalanced force will accelerate an object - changing its speed, its direction, or both its speed and direction." And something under the influence of gravity, acting as well as getting acted on, bound to a orbit fits that description.

Ps: a velocity doesn't really fit this description as it implies both a speed, and a defined direction. speed should be the correct word here, as gravity may change that direction. I'll leave it be though, as a reminder to myself :)