# UCI-UCSD Logic & Philosophy of Science

**Laura Ruetsche**

University of Pittsburgh

## “ In space, no one can hear you steam:

Hawking radiation, Rindler quanta, and

the interpretation of quantum field theory”

Two putative consequences of relativistic quantum field theory are: (i) in
the non-exotic setting of Minkowski spacetime, an observer moving with
constant acceleration, through what a non-accelerating observer considers
a vacuum or no-particle state, is pelted with particles (the Unruh
effect); and (ii) in the more exotic setting of a spacetime containing a
black hole, an observer outside the black hole is pelted with particles
apparently emanating from the (evidently not so) black hole (the Hawking
effect). In each case, the pelted observer attributes the quantum field a
thermal state, a state whose statistical character is claimed to
reflect, in the case of the Unruh effect, the acceleration of the pelted
observer or, in the case of the Hawking effect, the initial mass of the
evaporating black hole. I hope in this non-technical talk to use the
Hawking and Unruh effects to illustrate what's at stake in some of
the interpretive questions that arise in connection with RQFT,
interpretive questions that are distinctive of RQFT, in the sense that
they don't arise for more mundane quantum theories.

## Friday, October 27, 2000

SST 777, 3 pm

*Wine & Cheese reception to follow*

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