49,344 research outputs found
Kinetic-growth self-avoiding walks on small-world networks
Kinetically-grown self-avoiding walks have been studied on Watts-Strogatz
small-world networks, rewired from a two-dimensional square lattice. The
maximum length L of this kind of walks is limited in regular lattices by an
attrition effect, which gives finite values for its mean value . For
random networks, this mean attrition length scales as a power of the
network size, and diverges in the thermodynamic limit (large system size N).
For small-world networks, we find a behavior that interpolates between those
corresponding to regular lattices and randon networks, for rewiring probability
p ranging from 0 to 1. For p < 1, the mean self-intersection and attrition
length of kinetically-grown walks are finite. For p = 1, grows with
system size as N^{1/2}, diverging in the thermodynamic limit. In this limit and
close to p = 1, the mean attrition length diverges as (1-p)^{-4}. Results of
approximate probabilistic calculations agree well with those derived from
numerical simulations.Comment: 10 pages, 7 figure
Analysis for time discrete approximations of blow-up solutions of semilinear parabolic equations
We prove a posteriori error estimates for time discrete approximations, for semilinear parabolic equations with solutions that might blow up in finite time. In particular we consider the backward Euler and the Crank–Nicolson methods. The main tools that are used in the analysis are the reconstruction technique and energy methods combined with appropriate fixed point arguments. The final estimates we derive are conditional and lead to error control near the blow up time
From globalization to deglobalization: Zooming into trade. Bruegel Special Report
After decades of increasing globalization both in trade, capital flows but even people to people movements, it seems the trend has turned
towards deglobalization. This article shows some evidence of the decrease in merchandise, capital and, to a lesser extent people to people
flows. In addition, zooming into trade, the article offers an account of the importance of the strategic competition between the US and
China to foster the deglobalization trend further. This is true for trade but even beyond in the tech and finance space. Finally, the demise
of the WTO could be one of the most relevant turning points towards deglobalization, especially as far as trade is concerned. This should
bring downward pressure to growth globally
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