Littérature scientifique sur le sujet « Marginal deformations of N=4 SYM »

We review recent work on the application of the non-commutative geometric framework to an interpretation of the moduli space of vacua of marginal deformations of N = 4 super Yang-Mills theories. At rational values of couplings, different regions of moduli space may be associated with D5-branes of various topologies, and orbifold dual descriptions exist which may be accessed by T-duality. Singularities in the moduli space are associated with topology change.

Sea ice is an important part of the Arctic climate system. In the recent decade, rapid changes in the sea ice conditions have been observed: sea ice extent and sea ice thickness are declining; conversely, ice drift speed and deformations are increasing [1–10]. The main aim of this paper was to describe the variability of sea ice conditions north of the Svalbard archipelago and analyze the changes occurring there. For most of the year, a stable polynya is observed north of the archipelago, which is commonly called “Whalers Bay”. The prevailing wind direction (8–9 months out of 12) is north-east, thus, almost throughout the whole year, conditions persist that support the flow of warmer Atlantic waters (AW) to the surface. Stable upwelling, together with the observed increase in AW’s temperature, contributes to the formation of the quasi-stationary polynya “Whalers Bay”. The ice conditions north of the Spitsbergen archipelago are changing extremely dynamically. However, all their diversity can be grouped into four main types. Type 1 — the area to the north of the archipelago is covered with ice; type 2 — the ice edge moves to the north of the archipelago; 3 — “Whalers Bay” polynya; 4 — an intermediate type, when a “passage” is formed to the Barents Sea between the ice edge and the northern coast of the archipelago. This study showed that since the mid-1990s the frequency of type 1 has significantly decreased, conversely, type 3 has become predominant, and the frequency of occurrence of type 2 has also increased. The maximum area of the polynya was observed in February 2012 and 2014, when the ice edge reached 82,5°N and 50°E, and 83°N and 46°E respectively. The lightest ice conditions were observed in 2012, 2013 and 2016. The main periods of 2–3, 5–6 and 14 years were identified in open water area variability. The ice cover to the north of the archipelago is largely presented by the conditions similar to the marginal ice zone with an actively changing ice edge configuration and the combined influence of factors characteristic of open sea areas and ice-covered areas. It is here that intense heat exchange takes place between the ocean and the atmosphere. The heat fluxes directed from the ocean to the atmosphere in the area of the polynya have increased by about 4 TW over the past 40 years. The highest correlation between the heat flux and the area of open water is observed with a lag of 2 months.

Abstract We construct a continuous one parameter family of AdS4× S1× S5 S-fold solutions of type IIB string theory which have nontrivial SL(2, ℤ) monodromy in the S1 direction. The solutions span a subset of a conformal manifold that contains the known $$ \mathcal{N} $$ N = 4 S-fold SCFT in d = 3, and generically preserve $$ \mathcal{N} $$ N = 2 supersymmetry. We also construct RG flows across dimensions, from AdS5× S5, dual to $$ \mathcal{N} $$ N = 4, d = 4 SYM compactified with a twisted spatial circle, to various AdS4×S1×S5 S-fold solutions, dual to d = 3 SCFTs. We construct additional flows between the AdS5 dual of the Leigh-Strassler SCFT and an $$ \mathcal{N} $$ N = 2 S-fold as well as RG flows between various S-folds.

Abstract We study mass deformations of $$ \mathcal{N} $$ N = 4, d = 4 SYM theory that are spatially modulated in one spatial dimension and preserve some residual supersymmetry. We focus on generalisations of $$ \mathcal{N} $$ N = 1∗ theories and show that it is also possible, for suitably chosen supersymmetric masses, to preserve d = 3 conformal symmetry associated with a co-dimension one interface. Holographic solutions can be constructed using D = 5 theories of gravity that arise from consistent truncations of SO(6) gauged supergravity and hence type IIB supergravity. For the mass deformations that preserve d = 3 superconformal symmetry we construct a rich set of Janus solutions of $$ \mathcal{N} $$ N = 4 SYM theory which have the same coupling constant on either side of the interface. Limiting classes of these solutions give rise to RG interface solutions with $$ \mathcal{N} $$ N = 4 SYM on one side of the interface and the Leigh-Strassler (LS) SCFT on the other, and also to a Janus solution for the LS theory. Another limiting solution is a new supersymmetric AdS4× S1× S5 solution of type IIB supergravity.

In this Thesis I analyze some aspects of a class of quantum field theories that can be obtained by marginally deforming N=4 SYM theory. These theories constitue a very non trivial example of N=1 superconformal actions in four dimensional space-time and play a role in the context of AdS/CFT. I begin by introducing superfield notations and constructing deformed theories following Leigh and Strassler procedure. Then an analysis of the finiteness properties of the actions is performed. Considering different specific cases, solutions of the superconformal constraint are given. The issues of conformal invariance and finiteness in the case of complex and real beta-deformed models are addressed. In the real beta case an all loop solution of the constraint is provided. In the case of complex deformation, it turns out that the condition of vanishing beta function leads to a result which is scheme dependent. In the second part of the work, anomalous dimensions of composite operators are computed. A new method for extracting protected operators in the chiral sector is introduced. Using the proposed procedure it is possible to gain a loop order in perturbative computations with respect to canonical methods. The structure of the chiral ring of the deformed theories is then classified up to three loops.