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# Gravity Problem

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I didnt major in physics but did a degree in a subject that contained a lot of it. Please can someone explain why the following isn`t a problem.

A star travels in a straight line at 99% the speed of light which doesnt cause any problems with General Relativity. But, stars are usually rotating. There are 3 axis of rotation for a star so lets say it is rotating around each also at 99% the speed of light.

We know that as something travels faster its mass increases but if we add up the cumulative total for the new mass of the star from the linear movement and rotation movement around all 3 axis then how does that not break relativity? I notice there is no rotation in relativity. While it works when describing the gravitational attraction between the Earth and Moon (because the Moon is tidal locked) then surely there is a problem when describing the attraction between the Earth and the Sun (because both are rotating)?

Is this a possible explanation for dark matter? That being that it doesnt exist, but scientists arent taking into account that the vast majority of stars and bodies in a galaxy are rotating around 3 axis?

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Posted (edited)
44 minutes ago, Cookie Monster said:

There are 3 axis of rotation

Elaborate.

The universe is expanding at 72 km/s per parsec. That is very far from lightspeed.
But technically stars don't move, because there is no outside frame of reference. The universe just gets less dense. Relativity stands strong.

Edited by zep73
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You need to think this through, and also learn more about Relativity, as you have left out the frames of reference.  Our Sun is going at over 99% of c, if you are photon travelling by... but you have to consider it from the photon's frame of reference.  Each party in these 'anomalies' sees something different - that's the whole idea of relativity...

If you have time, start reading this - it's from the man himself, Einstein.

Well-written, if in an old-fashioned style, and takes you slowly through to a point where hopefully you will get it, at around Section 7..  Not much maths, but you'll have to think.  Hard.

BTW, the rotation you refer to is a non-inertial reference frame, and it changes everything for any poor folks (or atoms..) that exist on the surface of the Star or other rotating body...  Not a problem, as such, as it is covered by the theories but you need different maths to work it all out.

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Posted (edited)
28 minutes ago, ChrLzs said:

You need to think this through, and also learn more about Relativity, as you have left out the frames of reference.  Our Sun is going at over 99% of c, if you are photon travelling by... but you have to consider it from the photon's frame of reference.  Each party in these 'anomalies' sees something different - that's the whole idea of relativity...

If you have time, start reading this - it's from the man himself, Einstein.

Well-written, if in an old-fashioned style, and takes you slowly through to a point where hopefully you will get it, at around Section 7..  Not much maths, but you'll have to think.  Hard.

BTW, the rotation you refer to is a non-inertial reference frame, and it changes everything for any poor folks (or atoms..) that exist on the surface of the Star or other rotating body...  Not a problem, as such, as it is covered by the theories but you need different maths to work it all out.

You forgot the most important part, Cookie Monster is a Multi-Dimensional being no one knows what planet he is from.

Edited by Manwon Lender
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8 hours ago, Cookie Monster said:

Is this a possible explanation for dark matter? That being that it doesnt exist, but scientists arent taking into account that the vast majority of stars and bodies in a galaxy are rotating around 3 axis?

Rotation on multiple axes is the same as rotation on one axis.

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12 hours ago, zep73 said:

But technically stars don't move, because there is no outside frame of reference.

Well, our star is orbiting the centre of the milky way. There is always a frame of reference.

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5 minutes ago, Emma_Acid said:

Well, our star is orbiting the centre of the milky way. There is always a frame of reference.

Yes, indeed, there are always lots of 'em!  But never a preferred one.. (and non-inertial ones suck...)

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Posted (edited)
3 minutes ago, ChrLzs said:

Yes, indeed, there are always lots of 'em!  But never a preferred one.. (and non-inertial ones suck...)

No of course. But with the universe the size it is currently you will always be able to find a object to which another object would be moving in relation to.

Now when the universe is much much much more expanded than it is today, then I'm less sure. If two objects are so far apart that any meaningful relationship between them is lost, then so (I guess) is any useful information regarding movement reference.

Edited by Emma_Acid
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