28,973 research outputs found
On finite volume effects in the chiral extrapolation of baryon masses
We perform an analysis of the QCD lattice data on the baryon octet and
decuplet masses based on the relativistic chiral Lagrangian. The baryon self
energies are computed in a finite volume at next-to-next-to-next-to leading
order (NLO), where the dependence on the physical meson and baryon masses
is kept. The number of free parameters is reduced significantly down to 12 by
relying on large- sum rules. Altogether we describe accurately more than
220 data points from six different lattice groups, BMW, PACS-CS, HSC, LHPC,
QCDSF-UKQCD and NPLQCD. Values for all counter terms relevant at NLO are
predicted. In particular we extract a pion-nucleon sigma term of 39
MeV and a strangeness sigma term of the nucleon of MeV. The flavour SU(3) chiral limit of the baryon octet and
decuplet masses is determined with MeV and MeV.
Detailed predictions for the baryon masses as currently evaluated by the ETM
lattice QCD group are made.Comment: 44 pages, 10 figures and 6 tables - the revised manuscript contains
the results of additional fits at the N^2LO level - 4 additional figures show
the size of finite volume corrections for each lattice point - more technical
details on the evaluation of finite volume effects are give
Abelian Duality
We show that on three-dimensional Riemannian manifolds without boundaries and
with trivial first real de Rham cohomology group (and in no other dimensions)
scalar field theory and Maxwell theory are equivalent: the ratio of the
partition functions is given by the Ray-Singer torsion of the manifold. On the
level of interaction with external currents, the equivalence persists provided
there is a fixed relation between the charges and the currents.Comment: 11 pages, LaTeX, no figures, a reference added, submitted to Phys.
Rev.
Opposite kinetics of L-leucine and L-phenylalanine induced insulin release studies with the perfused rat pancreas
An optimal algorithm for the on-line closest-pair problem
We give an algorithm that computes the closest pair in a set of points in -dimensional space on-line, in ime. The algorithm only uses algebraic functions and, therefore, is optimal. The algorithm maintains a hierarchical subdivision of -space into hyperrectangles, which is stored in a binary tree. Centroids are used to maintain a balanced decomposition of this tree
Antarctic meteorite descriptions, 1980
Specimens found in the Alan Hills area include 361 ordinary chondrites, 4 carbonaceous chondrites, 6 achondrites, and 2 irons. Thirteen specimens measured over 11 cm in diameter and 69 between 5 to 10 cm in diameter are reported. The remainder of the finds were small, and many were paired. One of the irons was estimated to weigh about 20 kilograms
Polarizations and Nullcone of Representations of Reductive Groups
The paper starts with the following simple observation. Let V be a representation of a reductive group G, and let f_1,f_2,...,f_n be homogeneous invariant functions. Then the polarizations of f_1,f_2,...,f_n define the nullcone of k 0} h(t) x = 0 for all x in L. This is then applied to many examples. A surprising result is about the group SL(2,C) where almost all representations V have the property that all linear subspaces of the nullcone are annihilated. Again, this has interesting applications to the invariants on several copies. Another result concerns the n-qubits which appear in quantum computing. This is the representation of a product of n copies of on the n-fold tensor product C^2 otimes C^2 otimes ... otimes C^2. Here we show just the opposite, namely that the polarizations never define the nullcone of several copies if n <= 3. (An earlier version of this paper, distributed in 2002, was split into two parts; the first part with the title ``On the nullcone of representations of reductive groups'' is published in Pacific J. Math. {bf 224} (2006), 119--140.
M-Theory on (K3 X S^1)/Z_2
We analyze -theory compactified on where the
changes the sign of the three form gauge field, acts on as a parity
transformation and on K3 as an involution with eight fixed points preserving
SU(2) holonomy. At a generic point in the moduli space the resulting theory has
as its low energy limit N=1 supergravity theory in six dimensions with eight
vector, nine tensor and twenty hypermultiplets. The gauge symmetry can be
enhanced (e.g. to ) at special points in the moduli space. At other
special points in the moduli space tensionless strings appear in the theory.Comment: LaTeX file, 11 page
Preparing projected entangled pair states on a quantum computer
We present a quantum algorithm to prepare injective PEPS on a quantum
computer, a class of open tensor networks representing quantum states. The
run-time of our algorithm scales polynomially with the inverse of the minimum
condition number of the PEPS projectors and, essentially, with the inverse of
the spectral gap of the PEPS' parent Hamiltonian.Comment: 5 pages, 1 figure. To be published in Physical Review Letters.
Removed heuristics, refined run-time boun
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