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arXiv · 1801.07925

Stability of the 2+2 fermionic system with point interactions

Thomas Moser·Robert Seiringer
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Abstract

We give a lower bound on the ground state energy of a system of two fermions of one species interacting with two fermions of another species via point interactions. We show that there is a critical mass ratio m_c \approx 0.58 such that the system is stable, i.e., the energy is bounded from below, for m \in [m_c, m_c^{-1}]. So far it was not known whether this 2+2 system exhibits a stable region at all or whether the formation of four-body bound states causes an unbounded spectrum for all mass ratios, similar to the Thomas effect. Our result gives further evidence for the stability of the more general N+M system.

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Thomas Moser, Robert Seiringer. 2018-06-11. Stability of the 2+2 fermionic system with point interactions. https://doi.org/10.1007/s11040-018-9275-3

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