منابع مشابه
Summing one-loop graphs at multiparticle threshold.
It is shown that the technique recently suggested by Lowell Brown for summing the tree graphs at threshold can be extended to calculate the loop effects. Explicit result is derived for the sum of one-loop graphs for the amplitude of threshold production of n on-mass-shell particles by one virtual in the unbroken λφ 4 theory. It is also found that the tree-level amplitude of production of n part...
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By explicitly allowing for topology to change as a function of time, two-dimensional quantum gravity defined through causal dynamical triangulations gives rise to a new continuum string field theory. Within a matrix-model formulation we show that – rather remarkably – the associated sum over all genera can be performed in closed form, leading to a nonperturbative definition of CDT string field ...
متن کاملOn common neighborhood graphs II
Let G be a simple graph with vertex set V (G). The common neighborhood graph or congraph of G, denoted by con(G), is a graph with vertex set V (G), in which two vertices are adjacent if and only if they have at least one common neighbor in G. We compute the congraphs of some composite graphs. Using these results, the congraphs of several special graphs are determined.
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2003
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s2003-01385-y