On the notion of "the same physics in all spacetimes"

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Brunetti, Fredenhagen and Verch (BFV) have shown how the
notion of local covariance for quantum field theories can be formulated
in terms of category theory: a theory being described as a functor from
a category of spacetimes to a category of (C)-algebras. We discuss
whether this condition is sufficient to guarantee that a theory represents
‘the same physics’ in all spacetimes, giving examples to show that
it does not. A new criterion, dynamical locality, is formulated, which
requires that descriptions of local physics based on kinematical and dynamical
considerations should coincide. Various applications are given,
including a proof that dynamical locality for quantum fields is incompatible
with the possibility of covariantly choosing a preferred state in
each spacetime.
As part of this discussion we state a precise condition that should
hold on any class of theories each representing the same physics in all
spacetimes. This condition holds for the dynamically local theories but
is violated by the full class of locally covariant theories in the BFV sense.
The majority of results described form part of forthcoming papers
with Rainer Verch [16].
Original languageEnglish
Title of host publicationQuantum Field Theory and Gravity. Conceptual and mathematical advances in the search for a unified framework. The volume emerged from the international conference "Quantum Field Theory and Gravity" held in Regensburg 28 September - 1 October 2010
EditorsF Finster, O Mueller, M Nardmann, J Tolksdorf, E Zeidler
Number of pages21
ISBN (Print)978-3-0348-0042-6
Publication statusPublished - 2012

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