Dynamic Realization of the Unruh Effect for a Geodesic Observer

  • Sumanta ChakrabortyEmail author
Part of the Springer Theses book series (Springer Theses)


In this chapter we present a dynamical version of the Unruh effect in a two dimensional model forming a black hole. In this two-dimensional collapse model, a scalar field coupled to the dilaton gravity, moving leftwards, collapses to form a black hole. The observers at the right null infinity witness a thermal flux of radiation resulting from the time dependent geometry leading to a black hole formation and its subsequent evaporation, in an expected manner. Remarkably, even the observers at left null infinity witness a thermal radiation, without experiencing any change of spacetime geometry and despite being inertial observers. We have also highlighted the conceptual similarity of this phenomenon with the standard Unruh effect in flat spacetime.


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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of Theoretical PhysicsIndian Association for the Cultivation of ScienceJadavpur, KolkataIndia

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