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Physics

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Coupling (piping)

Einstein

Horizon

Gauss

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Computer network

Theoretical physics

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Mathematical physics

Computer science

Black hole (networking)

Scalar (mathematics)

Quantum mechanics

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Physical Review Letters

We consider a general Einstein-scalar-Gauss-Bonnet theory with a coupling function $f(\ensuremath{\phi})$. We demonstrate that black-hole solutions appear as a generic feature of this theory since a regular horizon and an asymptotically flat solution may be easily constructed under mild assumptions for $f(\ensuremath{\phi})$. We show that the existing no-hair theorems are easily evaded, and a large number of regular black-hole solutions with scalar hair are then presented for a plethora of coupling functions $f(\ensuremath{\phi})$.

Evasion of No-Hair Theorems and Novel Black-Hole Solutions in Gauss-Bonnet Theories