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arXiv · 2304.05188

The quantum dynamics of Lagrange multipliers

Enrique Álvarez·Jesús Anero·Carmelo P. Martin·Eduardo Velasco-Aja
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Abstract

When implementing a non-linear constraint in quantum field theory by means of a Lagrange multiplier, $\l(x)$, it is often the case that quantum dynamics induce quadratic and even higher order terms in $\l(x)$, which then does not enforce the constraint anymore. This is illustrated in the case of Unimodular Gravity, where the constraint is that the metric tensor has to be unimodular ($g(x)\equiv \det\,g_{\m\n}(x)=-1$).

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Enrique Álvarez, Jesús Anero, Carmelo P. Martin, Eduardo Velasco-Aja. 2023-04-11. The quantum dynamics of Lagrange multipliers. https://doi.org/10.1103/physrevd.108.026013

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