In this paper we propose a new class of tree machines, called generalized compressed tree machines. Generalized compressed tree machines are obtained from complete binary tree machines by performing certain`con-traction' operations. A generalized compressed tree machine of height h has approximately 25% less number of processors than a complete binary tree of height h. We show that these machin...

This paper continues a program extending results related to the descriptive characterization of the CFLs in terms of deenability in the weak monadic second-order theory of trees to the TALs and the entire hierarchy of Weir's Control Languages. Previously, we have shown that the languages in this hierarchy can be characterized by deenability in the weak monadic second-order theories of a general...

Loopy and generalized belief propagation are popular algorithms for approximate inference in Markov random fields and Bayesian networks. Fixed points of these algorithms correspond to extrema of the Bethe and Kikuchi free energy (Yedidia et al., 2001). However, belief propagation does not always converge, which motivates approaches that explicitly minimize the Kikuchi/Bethe free energy, such as...

The NLIE (the non-linear integral equation equivalent to the Bethe Ansatz equations for finite size) is generalized to excited states, that is states with holes and complex roots over the antiferromagnetic ground state. We consider the sine-Gordon/massive Thirring model (sG/mT) in a periodic box of length L using the light-cone approach, in which the sG/mT model is obtained as the continuum lim...

The isoscalar twist-two generalized parton distributions (GPDs) of the pion and the kaon are calculated in a Poincaré covariant Bethe-Salpeter constituent quark model. Results are presented for several values of the parameters ξ and t. The results satisfy the form factor constraints and the polynomiality condition. For the pion GPD, also the isospin symmetry constraint is fulfilled. The influen...

Loopy and generalized belief propagation are popular algorithms for approximate inference in Markov random fields and Bayesian networks. Fixed points of these algorithms have been shown to correspond to extrema of the Bethe and Kikuchi free energy, both of which are approximations of the exact Helmholtz free energy. However, belief propagation does not always converge, which motivates approache...

Many multiple alignment methods implicitly or explicitly try to minimize the amount of biological change implied by an alignment. At the level of sequences, biological change is measured along a phylogenetic tree, a structure frequently being predicted only after the multiple alignment instead of together with it. The Generalized Tree Alignment problem addresses both questions simultaneously. I...

The one dimensional Heisenberg model in the presence of orbital degeneracy is studied at the SU(4) symmetric point by means of Bethe ansatz. Following Sutherland’s previous work on an equivalent model, we discuss the ground state and the low-lying excitations more extensively in connection to the spin systems with orbital degeneracy. We show explicitly that the ground state is a SU(4) singlet. ...

We construct the fusion operators in the generalized τ -model using the fused L-operators, and verify the fusion relations with the truncation identity. The algebraic Bethe Ansatz discussion is conducted on two special classes of τ -models which include the superintegrable chiral Potts model. We then perform the parallel discussion on the six-vertex model at roots of unity, and demonstrate that...

The bound state Bethe-Salpeter amplitude was expressed by Nakanishi using a two-dimensional integral representation, in terms of a smooth weight function g, which carries the detailed dynamical information. A similar, but one-dimensional, integral representation can be obtained for the Light-Front wave function in terms of the same weight function g. By using the generalized Stieltjes transform...