From Wavefunction Sign Structure to Static Correlation

2025/11/03 by Dubecký, Matúš
#Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Strongly Correlated Electrons (cond-mat.str-el)

paper · doi:10.48550/arxiv.2511.01569

Abstract

Static correlation, the breakdown of mean-field theory in correlated many-fermion systems, can be reframed as a quantitative gauge of the fermion-sign problem. The variational energy gap between correlated wavefunctions constrained by mean-field and exact Dirichlet nodes defines a nodal penalty driven by their topological differences. Method-agnostic and dictated solely by the sign structure of the wavefunction, this penalty measures the intrinsic complexity of fermionic correlations. This framework unifies orbital and real-space views and opens a general route toward a rigorous, method-independent decomposition of electron correlation, guiding topology-aware approaches and future node-centric strategies.

Citations

• Understanding Discrepancies of Wavefunction Theories for Large Molecules
• Probing Quantum Efficiency: Exploring System Hardness in Electronic Ground State Energy Estimation
• Nodal structures of few electron atoms

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