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arXiv · 2109.07500

Universality of a truncated sigma-model

Andrei Alexandru·Paulo F. Bedaque·Andrea Carosso·Andy Sheng
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Abstract

Bosonic quantum field theories, even when regularized using a finite lattice, possess an infinite dimensional Hilbert space and, therefore, cannot be simulated in quantum computers with a finite number of qubits. A truncation of the Hilbert space is then needed and the physical results are obtained after a double limit: one to remove the truncation and another to remove the regulator (the continuum limit). A simpler alternative is to find a model with a finite dimensional Hilbert space belonging to the same universality class as the continuum model (a "qubitization"), so only the space continuum limit is required. A qubitization of the $1+1$ dimensional asymptotically free $O(3)$ nonlinear $\sigma$-model based on ideas of non-commutative geometry was previously proposed arXiv:1903.06577 and, in this paper, we provide evidence that it reproduces the physics of the $\sigma$-model both in the infrared and the ultraviolet regimes.

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BibTeXRIS

Andrei Alexandru, Paulo F. Bedaque, Andrea Carosso, Andy Sheng. 2021-09-15. Universality of a truncated sigma-model. https://doi.org/10.1016/j.physletb.2022.137230

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