functorial quantum field theory
Reshetikhin?Turaev model? / Chern-Simons theory
FQFT and cohomology
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Types of quantum field thories
In the context of higher dimensional WZW models the following 1-dimensional sigma-models are seen to be examples:
the free non-relativistic particle;
the massive Green-Schwarz superparticle (the D0 super p-brane).
(Azcarraga-Izqierdo 95, section 8.3 and 8.7) .
Write
for the coset obtained as the quotient of the Galilei group in some dimension $d$ by the group of rotations. This $H$ has a canonical global coordinate chart $(t,x, \dot x)$. We may regard it as the first order jet bundle to the bundle $\mathbb{R}^d \times \mathbb{R} \to \mathbb{R}$ whose sections are trajectories in Cartesian space $\mathbb{R}^d$ (the field bundle for the 1d sigma-model with target space $\mathbb{R}^d$).
Among the $H$-left invariant differential 2-forms on $H$ is
for some $m \in \mathbb{R}$ (where a contraction of vectors is understood).
This is a representative of a degree-2 cocycle in the Lie algebra cohomology of $Lie(H)$. We may regard this as the curvature of a connection 1-form
Hence the value of the action functional of the corresponding 1d pure (topological) WZW model on a field configuration is
where $L(x, \dot x) d t = \frac{1}{2}m \dot x^2 d t$ is the Lagrangian of the the free non-relativistic particle of mass $m$.
Evaluated on jet prolongations of sections of the field bundle, for which the relation $d x = \dot x d t$ holds, then the first term of this expression vanishes and so the resulting WZW-type action functional is that of the free non-relativistic particle.
See (Azcarraga-Izqierdo, section 8.3) for a useful account.