In this paper, we define twisted higher spin Dirac operators and explain how these invariant differential operators can be used to define more general higher spin Dirac operators acting on functions f(x) on R which then take values in general half-integer representations for the spin group. Mathematics Subject Classification (2010). 30G35, 42B35.

By employing an adaptive time-dependent density-matrix-renormalization-group method, the spin-flip process of polarons is investigated in a polymer chain with magnetic impurities. Being driven by an external electric field, a polaron carrying both spin 1/2 and charge +/-e moves at a constant speed in the polymer chain. When the polaron passes through a specific site, which couples to a magnetic...

In the present work, we have obtained the equation of state for neutron star matter considering the in uence of the ferromagnetic and antiferromagnetic spin state. We have also investigated the structure of neutron stars. According to our results, the spin asymmetry stiens the equation of state and leads to high mass for the neutron star.

Let G = Spin[4n+1] be the connected, simply connected complex Lie group of type B2n and let G = Spin(p, q) (p + q = 4n + 1) denote a (connected) real form. If q / ∈ {0, 1}, G has a nontrivial fundamental group and we denote the corresponding nonalgebraic double cover by G̃ = ̃ Spin(p, q). The main purpose of this paper is to describe a symmetry in the set of genuine parameters for the various G̃ ...

We derive the coherent state representation of the integrable spin chain Hamil-tonian with non-compact supersymmetry group G =SU(1, 1|1). By passing to the continuous limit, we find a spin chain sigma model describing a string moving on the supercoset G/H, H being the stabilizer group. The action is written in a manifestly G-invariant form in terms of the Cartan forms and the string coordinates...

It has been shown that the massless irreducible representations of the Poincaré group with continuous spin can be obtained from a classical point particle action which admits a generalization to a conformally invariant string action. The continuous spin string action is quantized in the BRST formalism. We show that the vacuum carries a continuous spin representation of the Poincaré group and th...

BACKGROUND AND PURPOSE The relationship between extracranial large-artery characteristics and arterial spin-labeling MR imaging may influence the quality of arterial spin-labeling-CBF images for older adults with and without vascular pathology. We hypothesized that extracranial arterial blood velocity can explain between-person differences in arterial spin-labeling data systematically across cl...