2
votes
Current bounds on the value of $g$ for antimatter
The ALPHA collaboration released their paper answering this today!
The result is that the gravity experienced by antimatter (anti-hydrogen) is
0.75 ± 0.13 (statistical + systematic) ± 0.16 (simulation)...
1
vote
Dark energy contributing to, or modifying, mass estimates?
The mass of a system is gravitationally attractive. Dark energy is gravitationally repulsive. Thus they have opposite influences on the observable kinematics of systems of galaxies. If a system is ...
1
vote
Can a body escape a black hole by being thrusted?
The quick answer is no because time and spatial coordinates twist roles. As well as you can only move in one direction in time (forwards), inside a black hole you can't go backward in the radial ...
1
vote
Modified Lie bracket
The reason to modify the lie bracket is the field dependence of $\zeta^\mu$.
For the full Einstein theory, the remaining parameters $\zeta^\mu$ persevering both gauge fixing and boundary conditions ...
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