1994/07/20 by José P. S. Lemos, Jose' P. S. Lemos · 193 citations
Physics and Astronomy · #Action (physics) #Black Holes and Theoretical Physics #Black brane #Black hole (networking) #Black string #Classical mechanics #Cosmology and Gravitation Theories #Einstein #Extremal black hole #General relativity #Mathematical physics #Physics #Quantum mechanics #Relativity and Gravitational Theory #Spacetime #String theory #Theoretical physics #Theory of relativity #gr-qc
paper · pdf · doi:10.1088/0264-9381/12/4/014
published in Classical and Quantum Gravity 12(4), 1081-1086 (IOP Publishing) · 11 pages, plaintex
arxiv created 1994/07/20 · openalex publication_date 1995/04/01 · arxiv updated 2010/04/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The Einstein-Hilbert action with a cosmological term is used to derive a new action in 1+1 spacetime dimensions. It is shown that the two-dimensional theory is equivalent to planar symmetry in General Relativity. The two-dimensional theory admits black holes and free dilatons, and has a structure similar to two-dimensional string theories. Since by construction these solutions also solve Einstein’s equations, such a theory can bring two-dimensional results into the four-dimensional real world. In particular the two-dimensional black hole is also a black hole in General Relativity. General Relativity is thought to be the correct theory from the largest conceivable scales up to the Planck length, 10 −33 cm. A place to test these tinyest radii can be found in the late stages of black hole evaporation. This is a non-trivial issue and one is still probing regions where a semi-classical approximation is valid. The two-dimensional (2D) black holes found in the context of string theories [1,2] are being used to compute and analyze the back-reaction of the radiation on the geometry [3,4,5]. Such 2D theories are, in principle, toy models and it is important to construct a link with the four-dimensional (4D) world. With this purpose, we consider the following action,