Light and lightning at the end of the public tunnel : reform of the electricity sector in the Southern Cone

The authors provide an overview of recent privatization experiences in Argentina, Brazil, and Chile. They focus on both achievements and outstanding problems in the electricity sector. They pay special attention to the issue of whether regulators can enforce compliance and sustain the spirit of reform - bringing the forces of competition to the sector - despite the unavoidable adjustments and fine-tuning that effective regulation requires. Among the lessons: Competition, rather than privatization, is the key to transforming the sector. For competition to work, several conditions must be met: 1) The primary energy source must be competitive for competition in the wholesale market to work. (In Chile, the fact that most of the water rights have been allocated to the major generator company seriously limits efficiency in the sector.) 2) Monopolistic stages must be formally separate from other stages, with clear rules for third-party access. (Here, the structure adopted by Argentina seems superior to that adopted by Chile.) 3) New entry into the system is the ultimate test of competition. The main gain from competition in electricity generation comes from the decentralization of decisions about when, how much, and what type of generation has to be brought to the market, rather than from short-term gains from minimizing costs. Overall, vertical and horizontal separation in the sector increases rather than reduces the burden and complexity of regulation. In a disintegrated system, the issues that arose in a traditional monopoly situation (fair rate of return, asset base, tariff to final consumers, and so on) are significantly increased. New issues include third-party access, the promotion of competition, interconnection pricing, and consistency of regulations across stages of competitive development. Restructuring and privatization are still in their early stages so lessons drawn from experience must be considered tentative.Decentralization,Economic Theory&Research,Environmental Economics&Policies,Markets and Market Access,Labor Policies,Economic Theory&Research,Markets and Market Access,Access to Markets,Environmental Economics&Policies,Banks&Banking Reform

Saddle towers with infinitely many ends

We prove the existence of nonperiodic, properly embedded minimal surfaces in $\mathbb{R}^2\times\mathbb{S}^1$ with genus zero, infinitely many ends and one limit end (in particular, they have infinite total curvature).Comment: 16 pages, 3 figure

Higher-order Floquet topological phases with corner and bulk bound states

We report the theoretical discovery and characterization of higher-order Floquet topological phases dynamically generated in a periodically driven system with mirror symmetries. We demonstrate numerically and analytically that these phases support lower-dimensional Floquet bound states, such as corner Floquet bound states at the intersection of edges of a two-dimensional system, protected by the nonequilibrium higher-order topology induced by the periodic drive. We characterize higher-order Floquet topologies of the bulk Floquet Hamiltonian using mirror-graded Floquet topological invariants. This allows for the characterization of a new class of higher-order "anomalous" Floquet topological phase, where the corners of the open system host Floquet bound states with the same as well as with double the period of the drive. Moreover, we show that bulk vortex structures can be dynamically generated by a drive that is spatially inhomogeneous. We show these bulk vortices can host multiple Floquet bound states. This "stirring drive protocol" leverages a connection between higher-order topologies and previously studied fractionally charged, bulk topological defects. Our work establishes Floquet engineering of higher-order topological phases and bulk defects beyond equilibrium classification and offers a versatile tool for dynamical generation and control of topologically protected Floquet corner and bulk bound states.Comment: v2: 13 pages, 8 figures, 3 appendices; new references, and new analytical and numerical work showing the robustness of Z invariant without diagonal mirror symmetrie