# What is the difference between SR and GR?

#### Mark Turner

##### Banned
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As per title question

The curvature of space/time caused by gravity.

S.R. is about systems without acceleration. G.R. includes affects of acceleration, including gravity.

in agreement with mathman, though possibly more simply put,

SR entails movement, and how different observers perceive time is dependent upon the relative velocity of those observers.

GR concerns Gravity, and the effects of mass on space and time.

to put it simply,

very simply put ,
SR entails movement, and how different observers perceive time is dependent upon relative velocity of those observers.
GR concerns Gravity, and the effects of mass on space and time.

Is what you mention about observers perceiving time , SR , the time dilation part of relativity ?

Is what you mention about observers perceiving time , SR , the time dilation part of relativity ?
Probably a good bit over-simplified, but yes.

An Internet Forum is not the best place to get educated, if you really want to learn about SR and GR, though.

Probably a good bit over-simplified, but yes.

An Internet Forum is not the best place to get educated, if you really want to learn about SR and GR, though.

I'd of thought a science forum would be the perfect place to learn , yourselves have been answering my questions !

I do have some basic knowledge of physics but SR and GR is quite confusing , almost imperceivable .

When time slows down , is it possible to reverse time flipping the direction of time ?

S.R. is about systems without acceleration. G.R. includes affects of acceleration, including gravity.

Actually, as long as there is no gravity, you can use SR. So SR can be used even in cases with coordinate acceleration. You just have to know how to do it, and be careful.

Actually, as long as there is no gravity, you can use SR. So it works for coordinate acceleration, if you are careful.
It could be said that SR is just a special case of GR.

When time slows down , is it possible to reverse time flipping the direction of time ?
The simplest answer that I can provide for you is No.

I'll let the "experts and knowledgeable" answer any further questions that you have.

Welcome to Sciforums.

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I'd of thought a science forum would be the perfect place to learn , yourselves have been answering my questions !

I do have some basic knowledge of physics but SR and GR is quite confusing , almost imperceivable .

When time slows down , is it possible to reverse time flipping the direction of time ?
.
The thing with science forums, like any public forum, they are open to any Tom, Dick or Harry. The trick is to sort the wheat from the chaff, or the experts and knowledgable from the nonsense. I'm only [probably like yourself, an amateur] and have learnt plenty from forums like this, supplemented with reputable reading of the likes of Sagan, Weinburg, Thorne, Rees.

I'm not sure I understand your "flipping time" question properly, but two important issues to remember are [1] All Frames of references, are equally valid and real, and [2] each frame always sees time pass at 1 second per second within his own frame.

The curvature of space/time caused by gravity.
Hmmm, can I tidy that up some?
The curvature/warping of spacetime is caused by matter/energy, and we see that effect as gravity.

Is what you mention about observers perceiving time , SR , the time dilation part of relativity ?
Yes...example: If you and I were approaching a BH, and me being far more intrepid then you, decided to have a look inside, while you observed at a safe distance......You would observe me approaching the EH, but gradually being continually red shifted until beyond the capabilities of your on board scopes and I would just fade from view from your perspective.We call that gravitational time dilation and gravitational redshift. From my position, I would continue on merrily and cross the EH and fall towards the center, eventually being torn asunder depending on the BH's size...a large SMBH, the tidal effects would not be felt right away...with a stellar size BH, I could invariably be torn asunder even before I crossed the EH. https://jila.colorado.edu/~ajsh/

Hmmm, can I tidy that up some?
The curvature/warping of spacetime is caused by matter/energy, and we see that effect as gravity.
How about I tidy that up some as well? The curvature/warping of spacetime is caused by the effect that gravity has on matter.

Hmmm, can I tidy that up some?
The curvature/warping of spacetime is caused by matter/energy, and we see that effect as gravity.
Good catch.

Curvature of spacetime is not caused by gravity. Curvature spacetime is gravity.

How about I tidy that up some as well? The curvature/warping of spacetime is caused by the effect that gravity has on matter.

The thing with science forums, like any public forum, they are open to any Tom, Dick or Harry. The trick is to sort the wheat from the chaff, or the experts and knowledgable from the nonsense. I'm only [probably like yourself, an amateur] and have learnt plenty from forums like this, supplemented with reputable reading of the likes of Sagan, Weinburg, Thorne, Rees.

I'm not sure I understand your "flipping time" question properly, but two important issues to remember are [1] All Frames of references, are equally valid and real, and [2] each frame always sees time pass at 1 second per second within his own frame.
I am only an enthusiast , I'd rather have the answers given than try to give answers .

If in different frames of reference both measure 1 second per second , who is correct ?

Good catch.

Curvature of spacetime is not caused by gravity. Curvature spacetime is gravity.
Are you saying spacetime is more than xyzt ?

I am only an enthusiast , I'd rather have the answers given than try to give answers .

If in different frames of reference both measure 1 second per second , who is correct ?

Both are equally correct in there own frame.