1,869 research outputs found
Thermodynamic properties of thin films of superfluid 3He-A
The pairing correlations in superfluid He-3 are strongly modified by
quasiparticle scattering off a surface or an interface. We present theoretical
results and predictions for the order parameter, the quasiparticle excitation
spectrum and the free energy for thin films of superfluid He-3. Both specular
and diffuse scattering by a substrate are considered, while the free surface is
assumed to be a perfectly reflecting specular boundary. The results are based
on self-consistent calculations of the order parameter and quasiparticle
excitation spectrum at zero pressure. We obtain new results for the phase
diagram, free energy, entropy and specific heat of thin films of superfluid
He-3.Comment: Replaced with an updated versio
SecDec-3.0: numerical evaluation of multi-scale integrals beyond one loop
SecDec is a program which can be used for the factorization of dimensionally
regulated poles from parametric integrals, in particular multi-loop integrals,
and the subsequent numerical evaluation of the finite coefficients. Here we
present version 3.0 of the program, which has major improvements compared to
version 2: it is faster, contains new decomposition strategies, an improved
user interface and various other new features which extend the range of
applicability.Comment: 46 pages, version to appear in Comput.Phys.Com
D = 5 maximally supersymmetric Yang-Mills theory diverges at six loops
The connection of maximally supersymmetric Yang-Mills theory to the (2,0)
theory in six dimensions has raised the possibility that it might be
perturbatively ultraviolet finite in five dimensions. We test this hypothesis
by computing the coefficient of the first potential ultraviolet divergence of
planar (large N_c) maximally supersymmetric Yang-Mills theory in D = 5, which
occurs at six loops. We show that the coefficient is nonvanishing. Furthermore,
the numerical value of the divergence falls very close to an approximate
exponential formula based on the coefficients of the divergences through five
loops. This formula predicts the approximate values of the ultraviolet
divergence at loop orders L > 6 in the critical dimension D = 4 + 6/L. To
obtain the six-loop divergence we first construct the planar six-loop
four-point amplitude integrand using generalized unitarity. The ultraviolet
divergence follows from a set of vacuum integrals, which are obtained by
expanding the integrand in the external momenta. The vacuum integrals are
integrated via sector decomposition, using a modified version of the FIESTA
program.Comment: 31 pages, revtex, 12 figure
Correlation functions in the non-relativistic AdS/CFT correspondence
We study the correlation functions of scalar operators in the theory defined
as the holographic dual of the Schroedinger background with dynamical exponent
z=2 at zero temperature and zero chemical potential. We offer a closed
expression of the correlation functions at tree level in terms of Fourier
transforms of the corresponding n-point functions computed from pure AdS in the
lightcone frame. At the loop level this mapping does not hold and one has to
use the full Schroedinger background, after proper regularization. We
explicitly compute the 3-point function comparing it with the specific 3-point
function of the non-relativistic theory of cold atoms at unitarity. We find
agreement of both 3-point functions, including the part not fixed by the
symmetry, up to an overall normalization constant.Comment: 32 pages, 7 figures; v2: typos corrected, references added and
additional discussion about the case of compact number-direction, includes
new appendix with the computations of the 2 and 3 point function for the
compact number-direction case. The general results remain the same. Version
published in Phys.Rev.
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