I don't get how is it that space is curved, yet you see stars that are light years away. how that happens when you cannot see beyond the horizon when standing on the beach??? how do you see bodies that are so far away, or are they?
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The curvature of the earth and the curvature of space are two very different things.
You don't see beyond the horizon because there's solid matter in the way.
When light from a distant star 'bends' as it passes a nearer massive object
so that the star's position appears to change, that's 'curvature of space'.
You don't see beyond the horizon because there's solid matter in the way.
When light from a distant star 'bends' as it passes a nearer massive object
so that the star's position appears to change, that's 'curvature of space'.
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On the very largest scales, we do not see any curvature of space-time.
"Space" should be relegated to the shelf with phlogiston, humors, and life forces.
Well, not really. Actually "space" is a useful concept in everyday life. So go ahead and think about space being separate from time. Just don't do it at the very largest scales - or the very smallest...
Gravity curves space-time (when something is very close to it). This was proved a century ago with the occultation of starlight by the Sun (Eddington 1919) which proved that a large mass like the Sun bends light. We now call this gravitational lensing, since gravity acts like a lens. So large masses, like stars and galaxies and black holes bend space, but the effect is proportional the 1/distance² so it space is only bent close to the mass. On longer scales it is very flat.
"Space" should be relegated to the shelf with phlogiston, humors, and life forces.
Well, not really. Actually "space" is a useful concept in everyday life. So go ahead and think about space being separate from time. Just don't do it at the very largest scales - or the very smallest...
Gravity curves space-time (when something is very close to it). This was proved a century ago with the occultation of starlight by the Sun (Eddington 1919) which proved that a large mass like the Sun bends light. We now call this gravitational lensing, since gravity acts like a lens. So large masses, like stars and galaxies and black holes bend space, but the effect is proportional the 1/distance² so it space is only bent close to the mass. On longer scales it is very flat.
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Well recent studies in cosmology show that the universes topology is 'flat'; but to answer you question on how space can curve and see a object behind another object, if you have a object with a extremely high mass it will bend the fabric of space, and the light emitted by a secondary object will curve around the high mass object, giving the illusion that it is located in a different location.
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There's nothing for stars to hide behind. There is no horizon. And yes, they are actually that far away. There are dozens of reasons we know that, research them yourself.