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Cold black holes in scalar-tensor theories

K. A. Bronnikov·C. P. Constantinidis·R. L. Evangelista·J. C. Fabris
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Abstract

We study the possible existence of black holes in scalar-tensor theories of gravity in four dimensions. Their existence is verified for anomalous versions of these theories, with a negative kinetic term in the Lagrangian. The Hawking temperature T_H of these holes is zero, while the horizon area is (in most cases) infinite. It is shown that an infinite value of T_H can occur only at a curvature singularity rather than a horizon. As a special case, the Brans-Dicke theory is studied in more detail, and two kinds of infinite-area black holes are revealed, with finite and infinite proper time needed for an infalling particle to reach the horizon.

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K. A. Bronnikov, C. P. Constantinidis, R. L. Evangelista, J. C. Fabris. 1997-10-20. Cold black holes in scalar-tensor theories. https://arxiv.org/abs/gr-qc/9710092

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