Abstract
Starting from a Geometrothermodynamics metric for the space of thermodynamic equilibrium states in the mass representation, we use numerical techniques to analyse the thermodynamic geodesics of a supermassive Reissner Nordström black hole in isolation. Appropriate constraints are obtained by taking into account the processes of Hawking radiation and Schwinger pair-production. We model the black hole in line with the work of Hiscock and Weems (Phys Rev D 41:1142–1151, 1990). It can be deduced that the relation which the geodesics establish between the entropy S and electric charge Q of the black hole extremises changes in the black hole’s mass. Indeed, the expression for the entropy of an extremal black hole is an exact solution to the geodesic equation. We also find that in certain cases, the geodesics describe the evolution brought about by the constant emission of Hawking radiation and charged-particle pairs.
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Notes
To be precise, Weinhold worked in the tangent space defined at a general point of the equilibrium manifold, although it is possible to use his metric as a measure of distance in the manifold itself [14].
\(\wedge \) stands for the exterior product, ‘\(\text {d}\)’ the exterior derivative, and \((\text {d}\varTheta )^n\) is equal to \(\text {d}\varTheta \wedge \cdots \wedge \text {d}\varTheta \), where \(\text {d}\varTheta \) appears n times.
The full value and its uncertainty, in SI units, are given in [40].
Note that it is also possible to choose Q as the dependent variable. This will be treated in greater detail in Sect. 4.
Two values are given in [1]—one for the emission of three massless neutrino species, and another (0.26792) valid when no massless neutrinos are produced, where by massless is meant a mass less than about \(10^{-10}\,\hbox {eV}\) (the black hole would be too cold to emit anything heavier) [1]. Since the upperbounds available nowadays for the mass of neutrino flavours [48] are much greater than this value, we use \(\alpha =0.26792\) when comparing our work with [1].
The full values and uncertainties, in SI units, are given in [40].
The rest energy of the positron (the particle with the same-sign charge as the black hole) is not taken into account; the large charge-to-mass ratio of this particle implies that the energy \(eQ/r_+\) it gains when repelled to infinity is much greater [1].
Here, \(\lambda _\alpha \) stands for the intensive thermodynamic variables of the system. At equilibrium, \(\lambda _\alpha =\frac{\partial U}{\partial E^\alpha }\Bigr |_{\begin{array}{c} E_0^\alpha \end{array}}\) [52].
For instance, in the case of the geodesic with constraints given by Eq. (29), we set \(Q(t=0) = 8\times 10^{8}\,{\hbox {m}}\) and \(M(t=0) = 3\times 10^{9}\,{\hbox {m}}\).
References
Hiscock, W.A., Weems, L.D.: Evolution of charged evaporating black holes. Phys. Rev. D 41, 1142–1151 (1990)
Wheeler, J.A., Ruffini, R.: Introducing the black hole. Phys. Today 24(1), 30–41 (1971)
Michell, J.: On the Means of discovering the Distance, Magnitude, etc. of the Fixed Stars. Philos. Trans. R. Soc. 74, 35–57 (1784)
Gillispie, C.C.: Pierre-Simon Laplace, 1749–1827: A Life in Exact Science, Chapter 19. Princeton, Princeton University Press (1997). (reprinted in 2000)
Bekenstein, J.D.: Black holes and the second law. Lett. Nuovo Cim. 4, 737–740 (1972)
Bardeen, J.M., Carter, B., Hawking, S.W.: The four laws of black hole mechanics. Commun. Math. Phys. 31, 161–170 (1973)
Hawking, S.W.: Black hole explosions? Nature 248, 30–31 (1974)
Quevedo, H.: Geometrothermodynamics. J. Math. Phys. 48, 013506 (2007)
Quevedo, H., Quevedo, M.N.: Fundamentals of Geometrothermodynamics. In: Electronic Journal of Theoretical Physics—Zacatecas Proceedings II, pp. 1–16 (2011). Edited by Dvoeglazov, V.V., Molgado A., Ortiz, C. (Workshop Editors) and López Bonilla, J. L., Licata I., Sakaji, A. (EJTP Editors)
Gibbs, J.W.: The Collected Works of J. Willard Gibbs, 1st edn. Yale University Press, New Haven (1948)
Carathéodory, C.: Untersuchungen über die Grundlagen der Thermodynamik. Math. Ann. 67, 355–386 (1909). English translation by Kestin, J.: Investigation into the foundations of thermodynamics. In: Kestin, J. (ed.) The Second Law of Thermodynamics, pp. 229–256. Dowden, Hutchinson and Ross, Stroudsburg (1976)
Rao, C.R.: Information and accuracy attainable in the estimation of statistical parameters. Bull. Calcutta Math. Soc. 37(3), 81–91 (1945)
Hermann, R.: Geometry, Physics, and Systems. M. Dekker, New York (1973)
Andresen, B., Berry, R.S., Gilmore, R., Ihrig, E., Salamon, P.: Thermodynamic geometry and the metrics of Weinhold and Gilmore. Phys. Rev. A 37, 845–848 (1988)
Weinhold, F.: Metric geometry of equilibrium thermodynamics. J. Chem. Phys. 63, 2479–2483 (1975)
Weinhold, F.: Metric geometry of equilibrium thermodynamics. II. J. Chem. Phys. 63, 2484–2487 (1975)
Weinhold, F.: Metric geometry of equilibrium thermodynamics. III. J. Chem. Phys. 63, 2488–2495 (1975)
Weinhold, F.: Metric geometry of equilibrium thermodynamics. IV. J. Chem. Phys. 63, 2496–2501 (1975)
Weinhold, F.: Metric geometry of equilibrium thermodynamics. V. J. Chem. Phys. 65, 559–564 (1976)
Ruppeiner, G.: Thermodynamics: a Riemannian geometric model. Phys. Rev. A 20, 1608–1613 (1979)
Salamon, P., Nulton, J., Ihrig, E.: On the relation between entropy and energy versions of thermodynamic length. J. Chem. Phys. 80, 436–437 (1984)
Nulton, J., Salamon, P., Andresen, B., Anmin, Qi: Quasistatic processes as step equilibrations. J. Chem. Phys. 83, 334–338 (1985)
Diósi, L., Kulacsy, K., Lukács, B., Rácz, A.: Thermodynamic length, time, speed, and optimum path to minimize entropy production. J. Chem. Phys. 105, 11220–11225 (1996)
Crooks, G.E.: Measuring thermodynamic length. Phys. Rev. Lett 99, 100602 (2007)
Quevedo, H., Sánchez, A.: Geometrothermodynamics of asymptotically anti-de Sitter black holes. J. High Energy Phys. 09, 034 (2008)
Salamon, P., Ihrig, E., Berry, R.S.: A group of coordinate transformations which preserve the metric of Weinhold. J. Math. Phys. 24, 2515–2520 (1983)
Mrugala, R., Nulton, J.D., Schön, J.C., Salamon, P.: Statistical approach to the geometric structure of thermodynamics. Phys. Rev. A 41, 3156–3160 (1990)
Bravetti, A., Lopez-Monsalvo, C.S., Nettel, F., Quevedo, H.: The conformal metric structure of Geometrothermodynamics. J. Math. Phys. 54, 033513 (2013)
Bravetti, A., Momeni, D., Myrzakulov, R., Quevedo, H.: Geometrothermodynamics of higher dimensional black holes. Gen. Relativ. Gravit. 45, 1603–1617 (2013)
Quevedo, H., Sánchez, A., Vázquez, A.: Relativistic like structure of classical thermodynamics. Gen. Relativ. Gravit. 47, 36 (2015)
Álvarez, J.L., Quevedo, H., Sánchez, A.: Unified geometric description of black hole thermodynamics. Phys. Rev. D 77, 084004 (2008)
Quevedo, H.: Geometrothermodynamics of black holes. Gen. Relativ. Gravit. 40, 971–984 (2008)
Bravetti, A., Luongo, O.: Dark energy from geometrothermodynamics. Int. J. Geom. Methods Mod. Phys. 11(8), 1450071 (2014)
Han, Y., Chen, G.: Thermodynamics, geometrothermodynamics and critical behavior of (2+1)-dimensional black holes. Phys. Lett. B 714, 127–130 (2012)
Bravetti, A., Lopez-Monsalvo, C.S., Nettel, F., Quevedo, H.: Representation invariant Geometrothermodynamics: applications to ordinary thermodynamic systems. J. Geom. Phys. 81, 1–9 (2014)
Hendi, S.H., Panahiyan, S., Panah, B.E., Momennia, M.: A new approach toward geometrical concept of black hole thermodynamics. Eur. Phys. J. C 75, 507 (2015)
Hendi, S.H., Panahiyan, S., Panah, B.E.: Charged black hole solutions in Gauss–Bonnet-massive gravity. J. High Energy Phys. 2016(1), 129 (2016)
Hendi, S.H., Panahiyan, S., Panah, B.E., Armanfard, Z.: Phase transition of charged black holes in Brans–Dicke theory through geometrical thermodynamics. Eur. Phys. J. C 76, 396 (2016)
Vázquez, A., Quevedo, H., Sánchez, A.: Thermodynamic systems as extremal hypersurfaces. J. Geom. Phys. 60, 1942–1949 (2010)
The NIST Reference on Constants, Units, and Uncertainty. http://physics.nist.gov/cuu/index.html (2015). Accessed 2 Oct 2016
Caprio, M.A.: LevelScheme: a level scheme drawing and scientific figure preparation system for Mathematica. Comput. Phys. Commun. 171, 107–118 (2005). http://scidraw.nd.edu/levelscheme
Bekenstein, J.D.: Black holes and entropy. Phys. Rev. D 7, 2333–2346 (1973)
Hawking, S.W.: Particle creation by black holes. Commun. Math. Phys. 43, 199–220 (1975)
Smarr, L.: Mass formula for Kerr black holes. Phys. Rev. Lett. 30, 71–73 (1973)
Gibbons, G.W.: Vacuum polarization and the spontaneous loss of charge by black holes. Commun. Math. Phys. 44, 245–264 (1975)
Schwinger, J.: On gauge invariance and vacuum polarization. Phys. Rev. 82, 664–679 (1951)
Parentani, R., Spindel, P.: Hawking radiation. http://www.scholarpedia.org/article/Hawking_radiation (2011). Accessed 15 Jan 2016
Particle Data Group: Leptons. Phys. Lett. B 667, 479–548 (2008)
Hobson, M.P., Efstathiou, G., Lasenby, A.N.: General Relativity: An Introduction for Physicists, Chapter 11. Cambridge University Press, New York (2006)
Thornton, S.T., Rex, A.: Modern Physics for Scientists and Engineers, Chapter 15, 4th edn. Cengage Learning, Boston (2013)
Walecka, J.D.: Introduction to General Relativity, Chapter 14. World Scientific, Singapore (2007)
Gilmore, R.: Length and curvature in the geometry of thermodynamics. Phys. Rev. A 30, 1994–1997 (1984)
Salamon, P., Andresen, B., Gait, P.D., Berry, R.S.: The significance of Weinhold’s length. J. Chem. Phys. 73, 1001–1002 (1980). Erratum: J. Chem. Phys. 73, 5407 (1980)
Hawking, S.W., Horowitz, G.T., Ross, S.F.: Entropy, area, and black hole pairs. Phys. Rev. D 51, 4302–4314 (1995)
Hod, S.: Evidence for a null entropy of extremal black holes. Phys. Rev. D 61, 084018 (2000)
Teitelboim, C.: Action and entropy of extreme and nonextreme black holes. Phys. Rev. D 51, 4315–4318 (1995)
Carroll, S.M., Johnson, M.C., Randall, L.: Extremal limits and black hole entropy. J. High Energy Phys. 11, 109 (2009)
Das, S., Dasgupta, A., Ramadevi, P.: Can extremal black holes have nonzero entropy? Mod. Phys. Lett. A 12, 3067–3079 (1997)
Acknowledgements
C. F. would like to thank Prof. H. Quevedo of the Universidad Nacional Autónoma de México, Prof. J. Muscat (Department of Mathematics, University of Malta) and Prof. K. Zarb Adami (Institute of Space Sciences and Astronomy, University of Malta).
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Farrugia, C., Sultana, J. Thermodynamic geodesics of a Reissner Nordström black hole. Gen Relativ Gravit 49, 4 (2017). https://doi.org/10.1007/s10714-016-2169-4
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DOI: https://doi.org/10.1007/s10714-016-2169-4