Activities per year
Abstract
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].
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 language  English 

Title of host publication  Quantum 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 
Editors  F Finster, O Mueller, M Nardmann, J Tolksdorf, E Zeidler 
Publisher  Birkhauser 
Pages  207227 
Number of pages  21 
ISBN (Print)  9783034800426 
Publication status  Published  2012 
Activities
 1 Invited talk

Quantum Field Theory and Gravity
Chris Fewster (Keynote/plenary speaker)
28 Sep 2010 → 1 Oct 2010Activity: Talk or presentation › Invited talk