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 ?

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, 20169 yr by Mordred

So negative spacetime curvature is not a concept in GR?

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, 20169 yr by 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.

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?

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