Modified convex hull pricing for fixed load power markets

We consider fixed load power market with non-convexities originating from start-up and no-load costs of generators. The convex hull (minimal uplift) pricing method results in power prices minimizing the total uplift payments to generators, which compensate their potential profits lost by accepting centralized dispatch solution, treating as foregone all opportunities to supply any other output volume allowed by generator internal constraints. For each generator we define a set of output volumes, which are economically and technologically feasible in the absence of centralized dispatch, and propose to exclude output volumes outside the set from lost profit calculations. New pricing method results in generally different set of market prices and lower (or equal) total uplift payment compared to convex hull pricing algorithm.Comment: v.3 (section on comparison with convex hull pricing extended, references added

Topological Disorder Operators in Three-Dimensional Conformal Field Theory

Many abelian gauge theories in three dimensions flow to interacting conformal field theories in the infrared. We define a new class of local operators in these conformal field theories which are not polynomial in the fundamental fields and create topological disorder. They can be regarded as higher-dimensional analogues of twist and winding-state operators in free 2d CFTs. We call them monopole operators for reasons explained in the text. The importance of monopole operators is that in the Higgs phase, they create Abrikosov-Nielsen-Olesen vortices. We study properties of these operators in three-dimensional QED using large N_f expansion. In particular, we show that monopole operators belong to representations of the conformal group whose primaries have dimension of order N_f. We also show that monopole operators transform non-trivially under the flavor symmetry group, with the precise representation depending on the value of the Chern-Simons coupling.Comment: 24 pages, latex. v2: a reference to prior work has been adde

Monopole operators and mirror symmetry in three dimensions

We study vortex-creating, or monopole, operators in 3d CFTs which are the infrared limit of N = 2 and N = 4 supersymmetric QEDs in three dimensions. Using large-N-f expansion, we construct monopole operators which are primaries of short representations of the superconformal algebra. Mirror symmetry in three dimensions makes a number of predictions about such operators, and our results confirm these predictions. Furthermore, we argue that some of our large-N-f results are exact. This implies, in particular, that certain monopole operators in N = 4 d = 3 SQED with N-f = 1 are free fields. This amounts to a proof of 3d mirror symmetry in a special case

Monopole operators in three-dimensional N=4 SYM and mirror symmetry

We study non-abelian monopole operators in the infrared limit of three-dimensional SU(N_c) and N=4 SU(2) gauge theories. Using large N_f expansion and operator-state isomorphism of the resulting superconformal field theories, we construct monopole operators which are (anti-)chiral primaries and compute their charges under the global symmetries. Predictions of three-dimensional mirror symmetry for the quantum numbers of these monopole operators are verified.Comment: 23 pages, LaTex; v2: section 3.4 modified, section 3.5 extended, references adde

Belinfante Tensors Induced by Matter-Gravity Couplings

We show that any generally covariant coupling of matter fields to gravity gives rise to a conserved, on-shell symmetric energy-momentum tensor equivalent to the canonical energy-momentum tensor of the flat-space theory. For matter fields minimally coupled to gravity our algorithm gives the conventional Belinfante tensor. We establish that different matter-gravity couplings give metric energy-momentum tensors differing by identically conserved tensors. We prove that the metric energy-momentum tensor obtained from an arbitrary gravity theory is on-shell equivalent to the canonical energy-momentum tensor of the flat-space theory.Comment: 10 pages, LaTex; misprints corrected, references added; to appear in Physical Review

Non-supersymmetric deformations of the dual of a confining gauge theory

We introduce a computational technique for studying non-supersymmetric deformations of domain wall solutions of interest in AdS/CFT. We focus on the Klebanov-Strassler solution, which is dual to a confining gauge theory. From an analysis of asymptotics we find that there are three deformations that leave the ten-dimensional supergravity solution regular and preserve the global bosonic symmetries of the supersymmetric solution. Also, we show that there are no regular near-extremal deformations preserving the global symmetries, as one might expect from the existence of a gap in the gauge theory.Comment: 18 pages, latex, published as JHEP 0305 (2003) 03

Monopole Operators and Mirror Symmetry in Three-Dimensional Gauge Theories

Many gauge theories in three dimensions flow to interacting conformal field theories in the infrared. We define a new class of local operators in these conformal field theories that are not polynomial in the fundamental fields and create topological disorder. They can be regarded as higher-dimensional analogs of twist and winding-state operators in free 2-D CFTs. We call them monopole operators for reasons explained in the text. The importance of monopole operators is that in the Higgs phase, they create Abrikosov-Nielsen-Olesen vortices. We study properties of these operators in three-dimensional gauge theories using large N_f expansion. For non-supersymmetric gauge theories we show that monopole operators belong to representations of the conformal group whose primaries have dimension of order N_f. We demonstrate that these monopole operators transform non-trivially under the flavor symmetry group. We also consider topology-changing operators in the infrared limits of N=2 and N=4 supersymmetric QED as well as N=4 SU(2) gauge theory in three dimensions. Using large N_f expansion and operator-state isomorphism of the resulting superconformal field theories, we construct monopole operators that are primaries of short representation of the superconformal algebra and compute their charges under the global symmetries. Predictions of three-dimensional mirror symmetry for the quantum numbers of these monopole operators are verified. Furthermore, we argue that some of our large-N_f results are exact. This implies, in particular, that certain monopole operators in N=4 3-D SQED with N_f=1 are free fields. This amounts to a proof of 3-D mirror symmetry in these special cases.</p