Easy ways to explain special & general relativity

taybot
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If you had 3 sentences to describe special relativity to someone that doesn't know anything about it and 3 sentences to describe general relativity, how would you describe it?

I'm reading Fabric of the Cosmos and trying to get a grip on these theories, just a basic grip, I probably won't delve into it very deep but here is what I can come up with for special relativity:

The faster you move through space the slower your time goes.

And for general:

All the matter in the universe makes gravity which curves through space time, which is why the planets orbit the sun in a curve. Also, even if we are sitting still, we are always accelerating, which is why we feel the force of gravity. The force of gravity is the same thing you feel when you're in a car and the driver steps on the gas.
 
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taybot said:
The faster you move through space the slower your time goes.
No, your time just keeps ticking along at one second per second. Someone moving relative to you will see your time as moving slower than theirs just as you will see theirs moving slow relative to yours.

All the matter in the universe makes gravity which curves through space time, which is why the planets orbit the sun in a curve. Also, even if we are sitting still, we are always accelerating, which is why we feel the force of gravity. The force of gravity is the same thing you feel when you're in a car and the driver steps on the gas.
I think you have the right idea but if you are sitting still in the ISS, for example, you will not feel gravity. You feel gravity sitting on the Earth because it "warps" space-time, making your body want to follow the space-time geodesic towards the center of the Earth but your chair stops you so you feel pressure on your butt.
 
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