Vacuum Repels
General Relativity: both energy and momentum gravitate
2 f = 4 p G ( r + 3 p ) .

But vacuum (L) has negative pressure

pL = - rL  .

Hence vacuum repels.

If vacuum has negative pressure, why doesn't vacuum suck?

First Proof that pL=- rL:
dE + p dV = 0  .
If E=rLV with rL constant, then
( rL + pL ) dV = 0 .
QED.
Second Proof that pL=- rL:
The energy-momentum tensor Tmn of vacuum must be proportional to the only available tensor, the metric tensor gmn:
Tmn



rL 0 0 0
0 pL 0 0
0 0 pL 0
0 0 0 pL




= rL gmn = rL



1 0 0 0
0 -1 0 0
0 0 -1 0
0 0 0 -1




.
QED.

Why doesn't vacuum suck?