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View Full Version : Could Spacetime Curvature be an Illusion due to our vision?

magneto
2010-Jan-30, 12:37 PM
As far as Relativity. Is space really curved or could it be our perception of it because of our peripheral vision or something? How does relativity explain our perception of the curvature of space?

Argos
2010-Jan-30, 12:57 PM
No. The 'curvature' is just the mathematical expression of the effect that mass exerts in the space nearby. You donīt need Relativity to have curvature. When you throw a ball it describes a trajectory [parabola] under the influence of gravity. Thatīs 'curvature' for you [happening before your very eyes - no pun]. :)

Jens
2010-Jan-30, 01:09 PM
The curvature of space isn't measured by simply looking at things. It's more like, we know the orbit of Mercury, so measure where it should be, and take a photo with a camera mounted on a telescope, and see where Mercury appears. So it's not simply a question of human vision.

hhEb09'1
2010-Jan-30, 02:24 PM
No. The 'curvature' is just the mathematical expression of the effect that mass exerts in the space nearby. You donīt need Relativity to have curvature. When you throw a ball it describes a trajectory [parabola] under the influence of gravity. Thatīs 'curvature' for you [happening before your very eyes - no pun]. :)And remember, the curvature (http://www.bautforum.com/space-astronomy-questions-answers/69002-non-euclidean-geometry.html) is of spacetime. The curvature of a thrown ball is the same as the curvature of a bullet shot from a gun.

Jeff Root
2010-Jan-30, 02:25 PM
The "curvature" of spacetime is the existence of gravity. Curvature is a
description of how gravity behaves. It is a perfectly accurate description
within the limits of our ability to measure.

There are very few situations where the "curvature" is large enough to be
seen visibly. Gravitational lensing of very distant galaxies by nearer galaxies
is such a situation. All such visible "curvature" situations were predicted by
general relativity before anyone ever saw them. Their discovery helps to
confirm the accuracy of the descriptions of general relativity.

-- Jeff, in Minneapolis