@article {baldwin_distinct_2021,
title = {Distinct critical behaviors from the same state in quantum spin and population dynamics perspectives},
journal = {Phys. Rev. E},
volume = {103},
number = {1},
year = {2021},
note = {Place: ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA Publisher: AMER PHYSICAL SOC Type: Article},
month = {jan},
abstract = {There is a deep connection between the ground states of transverse-field spin systems and the late-time distributions of evolving viral populations-within simple models, both are obtained from the principal eigen-vector of the same matrix. However, that vector is the wave-function amplitude in the quantum spin model, whereas it is the probability itself in the population model. We show that this seemingly minor difference has significant consequences: Phase transitions that are discontinuous in the spin system become continuous when viewed through the population perspective, and transitions that are continuous become governed by new critical exponents. We introduce a more general class of models that encompasses both cases and that can be solved exactly in a mean-field limit. Numerical results are also presented for a number of one-dimensional chains with power-law interactions. We see that well-worn spin models of quantum statistical mechanics can contain unexpected new physics and insights when treated as population-dynamical models and beyond, motivating further studies.},
issn = {2470-0045},
doi = {10.1103/PhysRevE.103.012106},
author = {Baldwin, C. L. and Shivam, S. and Sondhi, S. L. and Kardar, M.}
}