Spin-dependent Hedin's equations

Hedin's equations for the electron self-energy and the vertex were originally derived for a many-electron system with Coulomb interaction. In recent years it has been increasingly recognized that spin interactions can play a major role in determining physical properties of systems such as nanoscale magnets or of interfaces and surfaces. We derive a generalized set of Hedin's equations for quantum many-body systems containing spin interactions, e.g. spin-orbit and spin-spin interactions. The corresponding spin-dependent GW approximation is constructed.Comment: 5 pages, 1 figur

The Quicksands of Originalism: Interpreting Minnesota’s Constitutional Past

There are several varieties of the “originalist” school of constitutional thought, but all subscribe in one degree or another to the belief that a constitutional clause should be interpreted according to its original meaning or the original intent of its authors. That original understanding or intent can be discerned from the text of the clause, the history of its drafting and ratification and, sometimes, early practices and court decisions interpreting that clause. It rightly has been called a “grand theory” because it is simple and clear, explains so much, and it has the almost irresistible attraction of being anchored firmly in history, a past illuminated by the writings and speeches of heroic figures -- the “founding fathers.” Like frontier settlers in the novels of O. E. Rölvaag, lawyers, legal scholars and jurists who attempt to interpret Minnesota\u27s Constitution on the basis of its original understanding or the framers\u27 intent encounter unexpected hardships, hazards, and deprivations. This article explores practical reasons why a strict originalist interpretation of the Minnesota Constitution has never taken hold, and probably never will. It does not address the worthiness of the originalist school of adjudication at all. It is both provoked and inspired by an essay published in these pages a year ago by Professor Russell Pannier on the decision of the Minnesota Supreme Court in the case of Abraham v. Hennepin County. There, the court held that an employee claiming retaliatory discharge under the state “whistleblower act” had a right to a jury trial under Article 1, section 4 of the Minnesota Constitution. Professor Pannier concluded that the Abraham court attempted to ride “originalist” and “non-originalist” horses in the same race; not mincing words, he found the court\u27s reasoning “incoherent” and “internally inconsistent.” But there is another view of Abraham, that with it, the court boldly built a contemporary structure for the analysis of the jury right that is faithful to the democratic order and harmonious with this state\u27s constitutional past

Conflict Within Wildlife Management on Western Landscapes Home on the Range

Most of the public lands within the Intermountain West are administered under a multiple-use mandate which emphasizes striking a balance in land use planning among the potentially competing values of livestock grazing, timber production, water supply, extraction of valuable fossil fuels, wildlife, and wilderness. This research sought to dive into a few of these competing values that involve large herbivores that compete for limited forage resources such as livestock and wildlife, on public lands, but also touched upon wildlife on private lands. The first component of research looked specifically at the coexistence of wildlife and livestock on both public and private lands and the conflict that arises between those interests. It outlined the perspectives of wildlife managers, agricultural producers, and boundary spanners (individuals who link wildlife managers and agricultural producers). The second component dove into the impacts of the decades-long megadrought that has gripped the Intermountain West and the ecological, societal, and economic impacts of this drought on wildlife, wildlife managers, and livestock producers on this working/wild landscape. Lastly, the final component looked specifically at past and future bison restoration efforts within the state of Utah and the conflict that exists within such efforts, especially in an era of extensive drought conditions. The qualitative method utilized in the research presented encompasses phenomenology. Phenomenology attempts to describe the common lived experiences of a variety of individuals; in this research, three major stakeholders were interviewed (wildlife managers, boundary spanners and agricultural producers/large landowners). The overarching themes that emerged related to (1) small improvements that state wildlife management agencies might institute to work more effectively with producers and large landowners to manage potential and existing conflicts (2) that adaptive management strategies much to be used to deal to depredation and damage incurred by private landowners and grazing permittees to incentivize their tolerance of wildlife and to acknowledge those bearing the “burden of conservation” (3) participation of stakeholders in the governance of natural resources, at a community-based level being the most palatable engagement strategy (4) transparency within every management decision is imperative utilizing the best-available science and lastly (5) that we must acknowledge the perspectives and values systems of all stakeholders, understanding that we all have a claim in the resources provided on a working/wild landscape

The Quicksands of Originalism: Interpreting Minnesota’s Constitutional Past

There are several varieties of the “originalist” school of constitutional thought, but all subscribe in one degree or another to the belief that a constitutional clause should be interpreted according to its original meaning or the original intent of its authors. That original understanding or intent can be discerned from the text of the clause, the history of its drafting and ratification and, sometimes, early practices and court decisions interpreting that clause. It rightly has been called a “grand theory” because it is simple and clear, explains so much, and it has the almost irresistible attraction of being anchored firmly in history, a past illuminated by the writings and speeches of heroic figures -- the “founding fathers.” Like frontier settlers in the novels of O. E. Rölvaag, lawyers, legal scholars and jurists who attempt to interpret Minnesota\u27s Constitution on the basis of its original understanding or the framers\u27 intent encounter unexpected hardships, hazards, and deprivations. This article explores practical reasons why a strict originalist interpretation of the Minnesota Constitution has never taken hold, and probably never will. It does not address the worthiness of the originalist school of adjudication at all. It is both provoked and inspired by an essay published in these pages a year ago by Professor Russell Pannier on the decision of the Minnesota Supreme Court in the case of Abraham v. Hennepin County. There, the court held that an employee claiming retaliatory discharge under the state “whistleblower act” had a right to a jury trial under Article 1, section 4 of the Minnesota Constitution. Professor Pannier concluded that the Abraham court attempted to ride “originalist” and “non-originalist” horses in the same race; not mincing words, he found the court\u27s reasoning “incoherent” and “internally inconsistent.” But there is another view of Abraham, that with it, the court boldly built a contemporary structure for the analysis of the jury right that is faithful to the democratic order and harmonious with this state\u27s constitutional past

Empirical modeling of the thermosphere: An overview

A summary is given of thermospheric density modeling history and standard atmospheres. In particular, the approaches of the Jacchia and MSIS models were compared and contrasted. It was concluded that the Jacchia models are best if drag is the primary concern. MSIS is superior for variations in composition and temperature variations and comparison with theoretical models is facilitated by the use of spherical harmonics, which also provide a simple and consistent way of obtaining simplifications. Advantages and disadvantages of both models are listed and discussed

Lifetime reduction of surface states at Cu, Ag and Au(111) caused by impurity scattering

We present density-functional results on the lifetime of the (111) surface state of the noble metals. We consider scattering on the Fermi surface caused by impurity atoms belonging to the 3d and 4sp series. The results are analyzed with respect to film thickness and with respect to separation of scattering into bulk or into surface states. While for impurities in the surface layer the overall trends are similar to the long-known bulk-state scattering, for adatom-induced scattering we find a surprising behavior with respect to the adatom atomic number. A plateau emerges in the scattering rate of the 3d adatoms, instead of a peak characteristic of the d resonance. Additionally, the scattering rate of 4sp adatoms changes in a zig-zag pattern, contrary to a smooth parabolic increase following Linde's rule that is observed in bulk. We interpret these results in terms of the weaker charge-screening and of interference effects induced by the lowering of symmetry at the surface

Frequency-dependent local interactions and low-energy effective models from electronic structure calculations

We propose a systematic procedure for constructing effective models of strongly correlated materials. The parameters, in particular the on-site screened Coulomb interaction U, are calculated from first principles, using the GW approximation. We derive an expression for the frequency-dependent U and show that its high frequency part has significant influence on the spectral functions. We propose a scheme for taking into account the energy dependence of U, so that a model with an energy-independent local interaction can still be used for low-energy properties.Comment: 16 pages, 5 figure

The quasiparticle spectral function in doped graphene

We calculate the real and imaginary electron self-energy as well as the quasiparticle spectral function in doped graphene taking into account electron-electron interaction in the leading order dynamically screened Coulomb coupling. Our theory provides the basis for calculating {\it all} one-electron properties of extrinsic graphene. Comparison with existing ARPES measurements shows broad qualitative agreement between theory and experiment. We also calculate the renormalized graphene momentum distribution function, finding a typical Fermi liquid discontinuity at k_F. We also provide a critical discussion of the relevant many body approximations (e.g. RPA) for graphene.Comment: 5 pages, 3 figure