1,031 research outputs found
Diffusion Processes on Power-Law Small-World Networks
We consider diffusion processes on power-law small-world networks in
different dimensions. In one dimension, we find a rich phase diagram, with
different transient and recurrent phases, including a critical line with
continuously varying exponents. The results were obtained using self-consistent
perturbation theory and can also be understood in terms of a scaling theory,
which provides a general framework for understanding processes on small-world
networks with different distributions of long-range links.Comment: 4 pages, 3 figures, added references, modified Fig. 2 with added data
(PRL, in press
An -expansion for Small-World Networks
I construct a well-defined expansion in for diffusion
processes on small-world networks. The technique permits one to calculate the
average over disorder of moments of the Green's function, and is used to
calculate the average Green's function and fluctuations to first non-leading
order in , giving results which agree with numerics. This technique
is also applicable to other problems of diffusion in random media.Comment: 7 pages Europhysics style, 3 figure
SN 1998bw at late phases
We present observations of the peculiar supernova SN 1998bw, which was
probably associated with GRB 980425. The photometric and spectroscopic
evolution is monitored up to 500 days past explosion. We also present modeling
based on spherically symmetric, massive progenitor models and very energetic
explosions. The models allow line identification and clearly show the
importance of mixing. From the late light curves we estimate that about 0.3-0.9
solar masses of ejected Nickel-56 is required to power the supernova.Comment: With 3 figures Accepted for ApJ Letter
Evolution equation for a model of surface relaxation in complex networks
In this paper we derive analytically the evolution equation of the interface
for a model of surface growth with relaxation to the minimum (SRM) in complex
networks. We were inspired by the disagreement between the scaling results of
the steady state of the fluctuations between the discrete SRM model and the
Edward-Wilkinson process found in scale-free networks with degree distribution
for [Pastore y Piontti {\it et al.},
Phys. Rev. E {\bf 76}, 046117 (2007)]. Even though for Euclidean lattices the
evolution equation is linear, we find that in complex heterogeneous networks
non-linear terms appear due to the heterogeneity and the lack of symmetry of
the network; they produce a logarithmic divergency of the saturation roughness
with the system size as found by Pastore y Piontti {\it et al.} for .Comment: 9 pages, 2 figure
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