# nLab black ring

Contents

### Context

#### Gravity

gravity, supergravity

# Contents

## Idea

The Einstein equations for gravity in dimension $\geq 5$ admit black hole solutions whose event horizon is not homeomorphic to an n-sphere, but has different topology. In particular in 5d-gravity and 5d supergravity there are solutions with topology $S^1 \times S^2$. These are called black rings.

Their KK-reduction down to 4 dimensions yields again ordinary black holes. This plays a central role in the discussion of black holes in string theory.

## References

The first black ring solution in was found, in D=5 gravity, in

The first black ring solution was found, in D=5 supergravity, in:

Review:

Dimensional reduction to black holes in D=4 gravity?:

On non-uniqueness:

As intersecting black M5-branes wrapped on a 4-manifold times the black ring’s circle:

following

More in the context of D1-D5-brane bound states

Last revised on March 7, 2021 at 13:14:29. See the history of this page for a list of all contributions to it.