10,615 research outputs found
The AGL Equation from the Dipole Picture
The AGL equation includes all multiple pomeron exchanges in the double
logarithmic approximation (DLA) limit, leading to an unitarized gluon
distribution in the small x regime. This equation was originally obtained using
the Glauber-Mueller approach. We demonstrate in this paper that the AGL
equation and, consequently, the GLR equation, can also be obtained from the
dipole picture in the double logarithmic limit, using an evolution equation,
recently proposed, which includes all multiple pomeron exchanges in the leading
logarithmic approximation. Our conclusion is that the AGL equation is a good
candidate for an unitarized evolution equation at small x in the DLA limit.Comment: 16 pages, 2 figures. Accepted for publication in Nuc. Phys.
Polytropic equation of state and primordial quantum fluctuations
We study the primordial Universe in a cosmological model where inflation is
driven by a fluid with a polytropic equation of state . We calculate the dynamics of the scalar factor and build a
Universe with constant density at the origin. We also find the equivalent
scalar field that could create such equation of state and calculate the
corresponding slow-roll parameters. We calculate the scalar perturbations, the
scalar power spectrum and the spectral index.Comment: 16 pages, 4 figure
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