2 research outputs found
Spin and Center of Mass in Axially Symmetric Einstein-Maxwell Spacetimes
We give a definition and derive the equations of motion for the center of
mass and angular momentum of an axially symmetric, isolated system that emits
gravitational and electromagnetic radiation. A central feature of this
formulation is the use of Newman-Unti cuts at null infinity that are generated
by worldlines of the spacetime. We analyze some consequences of the results and
comment on the generalization of this work to general asymptotically flat
spacetimes.Comment: 20 page
Geometric inequalities for axially symmetric black holes
A geometric inequality in General Relativity relates quantities that have
both a physical interpretation and a geometrical definition. It is well known
that the parameters that characterize the Kerr-Newman black hole satisfy
several important geometric inequalities. Remarkably enough, some of these
inequalities also hold for dynamical black holes. This kind of inequalities
play an important role in the characterization of the gravitational collapse,
they are closed related with the cosmic censorship conjecture. Axially
symmetric black holes are the natural candidates to study these inequalities
because the quasi-local angular momentum is well defined for them. We review
recent results in this subject and we also describe the main ideas behind the
proofs. Finally, a list of relevant open problem is presented.Comment: 65 pages, 5 figures. Review article, to appear in Class. Quantum
Grav. as Topical Review. Improved presentation, minor corrections, references
updat