120 research outputs found
Asymptotic expansion of the multi-orientable random tensor model
Three-dimensional random tensor models are a natural generalization of the
celebrated matrix models. The associated tensor graphs, or 3D maps, can be
classified with respect to a particular integer or half-integer, the degree of
the respective graph. In this paper we analyze the general term of the
asymptotic expansion in N, the size of the tensor, of a particular random
tensor model, the multi-orientable tensor model. We perform their enumeration
and we establish which are the dominant configurations of a given degree.Comment: 27 pages, 24 figures, several minor modifications have been made, one
figure has been added; accepted for publication in "Electronic Journal of
Combinatorics
The Multi-Orientable Random Tensor Model, a Review
After its introduction (initially within a group field theory framework) in
[Tanasa A., J. Phys. A: Math. Theor. 45 (2012), 165401, 19 pages,
arXiv:1109.0694], the multi-orientable (MO) tensor model grew over the last
years into a solid alternative of the celebrated colored (and colored-like)
random tensor model. In this paper we review the most important results of the
study of this MO model: the implementation of the expansion and of the
large limit ( being the size of the tensor), the combinatorial analysis
of the various terms of this expansion and finally, the recent implementation
of a double scaling limit
Combinatorial Hopf algebraic description of the multiscale renormalization in quantum field theory
We define in this paper several Hopf algebras describing the combinatorics of
the so-called multi-scale renormalization in quantum field theory. After a
brief recall of the main mathematical features of multi-scale renormalization,
we define assigned graphs, that are graphs with appropriate decorations for the
multi-scale framework. We then define Hopf algebras on these assigned graphs
and on the Gallavotti-Nicol\`o trees, particular class of trees encoding the
supplementary informations of the assigned graphs. Several morphisms between
these combinatorial Hopf algebras and the Connes-Kreimer algebra are given.
Finally, scale dependent couplings are analyzed via this combinatorial
algebraic setting.Comment: 26 pages, 3 figures; the presentation of the results has been
reorganized. Several details of various proofs are given and some references
have been adde
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