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The precise analog of the theta-quantization ambiguity of Yang-Mills theory exists for the real SU(2) connection formulation of general relativity. As in the former case theta labels representations of large gauge transformations, which are super-selection ...
Due to the unfavorable scaling of tensor-network methods with the refinement parameter M, new approaches are necessary to improve the efficiency of numerical simulations based on such states, in particular for gapless, strongly entangled systems. In one-di ...
Firstly, a dynamical analysis of adiabatic perturbations of a perfect fluid is performed to first-order about a general FLRW background using the 1 + 3 covariant and gauge-invariant formalism. The 1 + 3 covariant analog of the Mukhanov-Sasaki and Grishchuk ...
Particle and domain sizes strongly influence the properties of materials. Here we present an NMR approach based on paramagnetic relaxation enhancement (PRE) relayed by spin diffusion (SD), which allows us to determine lengths in the nm pm range. We demonst ...
A dynamical analysis of an effective homogeneous and irrotational Weyssenhoff fluid in general relativity is performed using the 1 + 3 covariant approach that enables the dynamics of the fluid to be determined without assuming any particular form for the s ...
A new expt. allows the identification of residues that feature slow conformational exchange in macromols. Rotations about dihedral angles that are slower than the global correlation time tc cause a modulation of the isotropic chem. shifts of the nuclei. If ...
We study spin interactions between two moving D-branes using the Green-Schwarz formalism of boundary states. We focus our attention on the leading terms for small velocities v, of the form v(4-n)/r(7-P+n) (v(2-n)/r(3-p+n)) for p-p (p-p + 4) systems, with 1 ...
Motivated by synthesis of new antiferromagnetic compounds with weak exchange coupling, a study of high magnetic field properties of the Heisenberg model on a square-lattice is undertaken here. Ordered spins at zero temperature cant toward the field directi ...
We study a resonant Bose-Fermi mixture at zero temperature by using the fixed-node diffusion Monte Carlo method. We explore the system from weak to strong boson-fermion interaction, for different concentrations of the bosons relative to the fermion compone ...
Neutron diffraction is used to investigate the field-induced, antiferromagnetically ordered state in the two-leg spin-ladder material (Hpip)(2)CuBr4. This "classical" phase, a consequence of weak interladder coupling, is nevertheless highly unconventional: ...