54,910 research outputs found
Finite Size Effects in the Anisotropic \lambda/4!(\phi^4_1 + \phi^4_2)_d Model
We consider the model on a
d-dimensional Euclidean space, where all but one of the coordinates are
unbounded. Translation invariance along the bounded coordinate, z, which lies
in the interval [0,L], is broken because of the boundary conditions (BC's)
chosen for the hyperplanes z=0 and z=L. Two different possibilities for these
BC's boundary conditions are considered: DD and NN, where D denotes Dirichlet
and N Newmann, respectively. The renormalization procedure up to one-loop order
is applied, obtaining two main results. The first is the fact that the
renormalization program requires the introduction of counterterms which are
surface interactions. The second one is that the tadpole graphs for DD and NN
have the same z dependent part in modulus but with opposite signs. We
investigate the relevance of this fact to the elimination of surface
divergences.Comment: 33 pages, 2 eps figure
Drip Paintings and Fractal Analysis
It has been claimed [1-6] that fractal analysis can be applied to
unambiguously characterize works of art such as the drip paintings of Jackson
Pollock. This academic issue has become of more general interest following the
recent discovery of a cache of disputed Pollock paintings. We definitively
demonstrate here, by analyzing paintings by Pollock and others, that fractal
criteria provide no information about artistic authenticity. This work has also
led to two new results in fractal analysis of more general scientific
significance. First, the composite of two fractals is not generally scale
invariant and exhibits complex multifractal scaling in the small distance
asymptotic limit. Second the statistics of box-counting and related staircases
provide a new way to characterize geometry and distinguish fractals from
Euclidean objects
Study of synthesis of glycerol Annual report, 30 Jun. 1967 - 30 Sep. 1968
Synthesis of glycero
From incommensurate correlations to mesoscopic spin resonance in YbRh2Si2
Spin fluctuations are reported near the magnetic field driven quantum
critical point in YbRh2Si2. On cooling, ferromagnetic fluctuations evolve into
incommensurate correlations located at q0=+/- (delta,delta) with delta=0.14 +/-
0.04 r.l.u. At low temperatures, an in plane magnetic field induces a sharp
intra doublet resonant excitation at an energy E0=g muB mu0 H with g=3.8 +/-
0.2. The intensity is localized at the zone center indicating precession of
spin density extending xi=6 +/- 2 A beyond the 4f site.Comment: (main text - 4 pages, 4 figures; supplementary information - 3 pages,
3 figures; to be published in Physical Review Letters
In search of phylogenetic congruence between molecular and morphological data in bryozoans with extreme adult skeletal heteromorphy
peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tsab20© Crown Copyright 2015. This document is the author's final accepted/submitted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it
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