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arXiv · 1607.00916

Pseudoscalar mesons in a finite cubic volume with twisted boundary conditions

Gilberto Colangelo·Alessio Vaghi
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Abstract

We study the effects of a finite cubic volume with twisted boundary conditions on pseudoscalar mesons. We first apply chiral perturbation theory in the p-regime and calculate the corrections for masses, decay constants, pseudoscalar coupling constants and form factors at next-to-leading order. We show that the Feynman-Hellmann theorem and the relevant Ward-Takahashi identity are satisfied. We then derive asymptotic formulae a la Luscher for twisted boundary conditions. We show that chiral Ward identities for masses and decay constants are satisfied by the asymptotic formulae in finite volume as a consequence of infinite-volume Ward identities. Applying asymptotic formulae in combination with chiral perturbation theory we estimate corrections beyond next-to-leading order for twisted boundary conditions.

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Gilberto Colangelo, Alessio Vaghi. 2016-07-04. Pseudoscalar mesons in a finite cubic volume with twisted boundary conditions. https://doi.org/10.1007/jhep07(2016)134

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