1,720,964 research outputs found
Almost conformal vacua and confinement
No full textDynamics of confining vacua which appear as deformed superconformal theory with a non-Abelian gauge symmetry, is studied by taking a concrete example of the sextet vacua of N = 2, SU(3) gauge theory with n(f) = 4, with equal quark masses. We show that the low-energy "matter" degrees of freedom of this theory consist of four magnetic monopole doublets of the low-energy effective SU(2) gauge group, one dyon doublet, and one electric doublet. We find a mechanism of cancellation of the beta function, which naturally but nontrivially generalizes that of Argyres-Douglas. Study of our SCFT theory as a limit of six colliding N = I vacua, suggests that the confinement in the present theory occurs in an essentially different manner from those vacua with dynamical abelianization, and involves strongly interacting non-Abelian magnetic monopoles. (C) 2003 Published by Elsevier Science B.V
Non-universal corrections to the tension ratios in softly broken N=2 SU(N) gauge theory
No full textCalculation by Douglas and Shenker of the tension ratios for vortices of
different N-alities in the softly broken N=2 supersymmetric SU(N) Yang-Mills
theory, is carried to the second order in the adjoint multiplet mass m.
Corrections to the ratios violating the well-known sine formula are found,
showing that it is not a universal quantity
Monopoles can be confined by 0, 1 or 2 vortices
No full textThere are three types of monopole in gauge theories with fundamental matter and N = 2 supersymmetry broken by a superpotential. There are unconfined 0-monopoles and also 1 and 2-monopoles confined respectively by one or two vortices transforming under distinct components of the unbroken gauge group. If a Fayet-Iliopoulos term is added then there are only 2-monopoles. Monopoles transform in the bifundamental representation of two components of the unbroken gauge symmetry, and if two monopoles share a component they may form a boundstate. Selection rules for this process are found, for example vortex number is preserved modulo 2. We find the tensions of the vortices, which are in general distinct, and also the conditions under which vortices are mutually BPS. Results are derived in field theory and also in MQCD, and in quiver theories a T-dual picture may be used in which monopoles are classified by quiver diagrams with two colors of vertices. © SISSA/ISAS 2005.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Higher Winding Strings and Confined Monopoles in N=2 SQCD
No full textWe consider composite string solutions in N=2 SQCD with the gauge group U(N), the Fayet--Iliopoulos term \xi \neq 0 and N (s)quark flavors. These bulk theories support non-Abelian strings and confined monopoles identified with kinks in the two-dimensional world-sheet theory. Similar and more complicated kinks (corresponding to composite confined monopoles) must exist in the world-sheet theories on composite strings. In a bid to detect them we analyze the Hanany--Tong (HT) model, focusing on a particular example of N=2. Unequal quark mass terms in the bulk theory result in the twisted masses in the N=(2,2) HT model. For spatially coinciding 2-strings, we find three distinct minima of potential energy, corresponding to three different 2-strings. Then we find BPS-saturated kinks interpolating between each pair of vacua. Two kinks can be called elementary. They emanate one unit of the magnetic flux and have the same mass as the conventional 't Hooft--Polyakov monopole on the Coulomb branch of the bulk theory (\xi =0). The third kink represents a composite bimonopole, with twice the minimal magnetic flux. Its mass is twice the mass of the elementary confined monopole. We find instantons in the HT model, and discuss quantum effects in composite strings at strong coupling. In addition, we study the renormalization group flow in this model
Nonabelian Monopoles and the Vortices that Confine Them
No full textNonabelian magnetic monopoles of Goddard-Nuyts-Olive-Weinberg type have
recently been shown to appear as the dominant infrared degrees of freedom in a
class of softly broken supersymmetric gauge theories in which the
gauge group is broken to various nonabelian subgroups by an adjoint
Higgs VEV. When the low-energy gauge group is further broken completely by
e.g. squark VEVs, the monopoles representing are confined by the
nonabelian vortices arising from the breaking of , discussed recently
(hep-th/0307278). By considering the system with , H = {SU(N)
\times U(1) {\o}{\mathbb Z}_N}, as an example, we show that the total magnetic
flux of the minimal monopole agrees precisely with the total magnetic flux
flowing along the single minimal vortex.
The possibility for such an analysis reflects the presence of free parameters
in the theory - the bare quark mass and the adjoint mass - such that
for the topologically nontrivial solutions of vortices and of
unconfined monopoles exist at distinct energy scales
Nonabelian Superconductors: Vortices and Confinement in SQCD
No full textWe study nonabelian vortices (flux tubes) in SU(N) gauge theories, which are
responsible for the confinement of (nonabelian) magnetic monopoles. In
particular a detailed analysis is given of SQCD with gauge group
SU(3) deformed by a small adjoint chiral multiplet mass. Tuning the bare quark
masses (which we take to be large) to a common value , we consider a
particular vacuum of this theory in which an SU(2) subgroup of the gauge group
remains unbroken. We consider flavors so that the SU(2)
sub-sector remains non asymptotically free: the vortices carrying nonabelian
fluxes may be reliably studied in a semi-classical regime. We show that the
vortices indeed acquire exact zero modes which generate global rotations of the
flux in an group. We study an effective world-sheet theory of
these orientational zero modes which reduces to an O(3) sigma
model in (1+1) dimensions. Mirror symmetry then teaches us that the dual SU(2)
group is not dynamically broken
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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