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Hawking temperature in the tunneling picture. (English) Zbl 1248.83046
Summary: We examine Hawking radiation from a Schwarzschild black hole in several reference frames using the quasi-classical tunneling picture. It is shown that when one uses $$\Gamma\propto\exp(\mathrm{Im}[\oint p\,dr])$$, rather than $$\Gamma\propto\exp(2\mathrm{Im}[\int p\,dr])$$ for the tunneling probability/decay rate one obtains twice the original Hawking temperature. The former expression for $$\Gamma$$ is argued to be correct since $$\oint p\,dr$$ is invariant under canonical transformations, while $$\int p\,dr$$ is not. Thus, either the tunneling methods of calculating Hawking radiation are suspect or the Hawking temperature is twice that originally calculated.

##### MSC:
 83C57 Black holes 83C47 Methods of quantum field theory in general relativity and gravitational theory