Weak–coupling calculation of the gap structure of doped n–leg Hubbard ladders Abstract In weak coupling, the spin gap in doped, even, n–leg periodic Hubbard ladders reflects the energy to break a pair into separate quasiparticles. Here we investigate the structure of the gap within a spin–fluctuation exchange approximation. We also calculate the amplitude for removing a singlet pair from two la...

In the heteromolecular title structure, C(10)H(8)N(2)S·C(8)H(6)O(4), the two components are linked by O-H⋯N hydrogen bonds to form a one-dimensional chain. These chains are further inter-connected by weak inter-molecular C-H⋯O hydrogen bonds and weak C-H⋯π inter-actions to generate a three-dimensional supra-molecular structure.

In the title compound, C(14)H(14)N(2)O(3), the dihedral angle between the pyrimidine and benzene rings is 14.9 (1)°. The mol-ecular structure is stabilized by weak intra-molecular C-H⋯O inter-actions and the crystal structure exhibits a weak inter-molecular π-π inter-action [centroid-centroid distance = 3.575 (3) Å].

In this paper we describe the range of values that can be taken by the fractional weak discrepancy of a poset subject to forbidden r+ s configurations, where r+s = 4. Generalizing previous work on weak discrepancy in [5, 12, 13], the notion of fractional weak discrepancy wdF (P ) of a poset P = (V,≺) was introduced in [7] as the minimum nonnegative k for which there exists a function f : V → R ...

A weak heap is a variant of a binary heap where, for each node, the heap ordering is enforced only for one of its two children. In 1993, Dutton showed that this data structure yields a simple worstcase-efficient sorting algorithm. In this paper we review the refinements proposed to the basic data structure that improve the efficiency even further. Ultimately, minimum and insert operations are s...

We show that if C is a proper model category, then the pro-category pro-C has a strict model structure in which the weak equivalences are the levelwise weak equivalences. This is related to a major result of [10]. The strict model structure is the starting point for many homotopy theories of pro-objects such as those described in [5], [17], and [19].

We consider radiative β-decay of the neutron in heavy baryon chiral perturbation theory. Nucleon-structure effects not encoded in the weak coupling constants gA and gV are determined at next-to-leading order in the chiral expansion, and enter at the [Formula: see text]-level, making a sensitive test of the Dirac structure of the weak currents possible.

A weak entwining structure in a 2-category K consists of a monad t and a comonad c, together with a 2-cell relating both structures in a way that generalizes a mixed distributive law. A weak entwining structure can be characterized as a compatible pair of a monad and a comonad, in 2-categories generalizing the 2-category of comonads and the 2-category of monads in K , respectively. This observa...

This paper presents a first investigation on the structure from motion problem from the combination of full and weak perspective images. This problem arises in multiresolution object modeling, where multiple zoomed-in or closeup views are combined with wider or distant reference views. The narrow field-of-view (FOV) images from the zoomed-in or closeup views can be approximated as weak perspect...