Negative Spacetime Curvature

[geordief]

Are there examples of Negative Spacetime Curvature?

 

Is it a term that only applies to the universe as a whole or are there local regions when spacetime curvature is negative (I think there are local regions where it is positive -such as planetary systems and galaxies?)

 

Might it apply to the interior space left behind by an explosion such as a supernova ?

[Mordred]

Not that I'm aware of other than the possible saddle shape of the universe.

 

Mass and energy results in positive curvature in GR.

Edited November 18, 2016 by Mordred

[geordief]

So negative spacetime curvature is not a concept in GR?

[Mordred]

as far as I know you would need anti-mass.

 

Keep in mind in Cosmology universe geometry isn't the same as curvature in GR. In GR curvature reflects the time component. In cosmology it is the expansion/contraction tendency due to total density vs critical density.

 

In the latter case time dilation isn't involved.

Edited November 18, 2016 by Mordred

[geordief]

as far as I know you would need anti-mass.

 

Keep in mind in Cosmology universe geometry isn't the same as curvature in GR. In GR curvature reflects the time component. In cosmology it is the expansion/contraction tendency due to total density vs critical density.

 

In the latter case time dilation isn't involved.

Is anti mass a purely speculative phenomenon unlike anti matter which has been experimentally verified?

 

Anti -mass ,if it existed would lead to anti -gravity , would it?

[Mordred]

yes its purely speculative. Yes it would also lead to antigravity.