Revision 1

Accepted · first revision · record

Title: Origin of the Hubbard-model pseudogap at cuprate-like coupling strength
Plain: At weak repulsion, computer studies trace the Hubbard model pseudogap to long-range magnetic fluctuations; whether the same holds at the strong repulsion relevant to cuprates is unsettled.
Precise: In the doped two-dimensional Hubbard model at $U/t \sim 6 \text{ to } 8$ and finite $T$, determine whether the antinodal pseudogap in the spectral function $A(k,\omega)$ arises from antiferromagnetic fluctuations with large correlation length $\xi(T)$ or from short-range singlet formation of Mott character, and locate the pseudogap endpoint in doping. An answer is a controlled calculation of $A(k,\omega)$ and $\xi(T)$ at strong coupling that discriminates the two.
Settled by: Diagrammatic Monte Carlo or cluster calculations with controlled convergence at $U/t \sim 7$ showing whether the pseudogap opening tracks the growth of $\xi(T)$.
Kind: well-posed
Answer type: classification
References: (empty)
Literature status: partially-resolved
Status note: Diagrammatic Monte Carlo (2024) established a spin-fluctuation pseudogap at weak to intermediate coupling; cluster methods at stronger coupling point to short-range Mott physics.
Posed since: (empty)