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Can someone please lucidly and non-mathematically explain Einstein's space-time curvature?

... spacetime curvature and tidal acceleration must be precisely the same thing in different languages...

Quote from: mxplxxxCan someone please lucidly and non-mathematically explain Einstein's space-time curvature?Sure. It's fairly simple. Spacetime curvature is the same thing as tidal gradients which are variations in the gravitational field. Think about four particles moving in a gravitational field all of which start from rest above the Earth's surface. Place two of the along a radial line and two of them along a circle of constant radius whose center is the center of the Earth (picture all of this in your mind). As observed from an observer who is in free fall with all four particles. One is above him, one below, and one on each side. When the entire system is allowed to be set in free-fall the one above him accelerates away from him to places higher in the field while the one below him accelerates away from him towards the ground. The particles on each side of him accelerate away from him. Each of these particles is moving away from him. That is spacetime curvature at work.As Kip Thorne explains in his book Black Holes and Time Warps Quote... spacetime curvature and tidal acceleration must be precisely the same thing in different languages...

I'm not sure but: space is filled with gravity (a continuous 'field' - no empty space). In some areas gravity is stronger than in others, this variation causes variation in the way things move and in how time in measured. These variation are called curvature in the mathematical discipline of topology( which is a slightly different meaning of curvature than is used in common parlance).

Thanks to all who replied. It would seem that the topic, like so many in physics, is one that is not widely understood.

What would be really nice is a peak physics body that sits in judgement on the many and varied physics theories and publishes a believability index (possibly as score out of 100) on each along with a commentary on the theory.

The problem with physics is that is long ago stopped being physics and became mathematics.

How many people really understand what string theory is all about?

Where do you get your 90% from? The problem with physics is that is long ago stopped being physics and became mathematics. Concepts and pictures are easily understandable; mathematics, especially that developed to try and explain reality, can be extraordinarily complex. How many people really understand what string theory is all about? Given that reality is likely a type of computer, it may be best described via state machines (as per attachment which is the state machine of a hydrogen atom). [ Invalid Attachment ]

Quote from: mxplxxx on 14/05/2015 09:31:06Can someone please lucidly and non-mathematically explain Einstein's space-time curvature?If you know much about math and want a precise meaning of spacetime curvature then read the page I created for it. It all has to do with what's known as geodesic deviation. See:...sorry, you cannot view external links. To see them, please REGISTER or LOGIN

... space is filled with gravity (...).

Not surprisingly, I don't understand... Does the curvature change when gravity changes? In what way is the gravitational field "uniform" if its strength is changing? How does that differ from the uniform field in GR? Anyway, thanks for any help you can provide.

Quote from: codei... space is filled with gravity (...). That is incorrect. In fact most of space is free of gravitational fields.

Really? Isn't the gravitational field supposed to extend to infinity. Unless you are talking about the radial distribution of the field.

Quote from: jeffreyHReally? Isn't the gravitational field supposed to extend to infinity. Unless you are talking about the radial distribution of the field.Anytime that you're talking about practical things one has to take into consideration what is actually measurable. The gravitational field at large distances from objects is so small that it's effectively zero. In any case you're neglecting all other sources if you think like that. Far from a single object other sources have to be taken into account and in that case they all have a tendency to average out to zero. If this wasn't the case then the concept of an inertial frame would have no meaning.

Quote from: PmbPhy on 18/05/2015 18:30:38Quote from: jeffreyHReally? Isn't the gravitational field supposed to extend to infinity. Unless you are talking about the radial distribution of the field.Anytime that you're talking about practical things one has to take into consideration what is actually measurable. The gravitational field at large distances from objects is so small that it's effectively zero. In any case you're neglecting all other sources if you think like that. Far from a single object other sources have to be taken into account and in that case they all have a tendency to average out to zero. If this wasn't the case then the concept of an inertial frame would have no meaning.Interesting that gravity decreases in magnitude the greater the distance from source the same as light does. I understand that gravity becomes negligible at distance, would this be an event horizon where things could remain stationary?