Massive Fields of Arbitrary Integer Spin in Symmetrical Einstein Space

We study the propagation of gauge fields with arbitrary integer spins in the symmetrical Einstein space of any dimensionality. We reduce the problem of obtaining a gauge-invariant Lagrangian of integer spin fields in such background to an purely algebraic problem of finding a set of operators with certain features using the representation of high-spin fields in the form of some vectors of pseudo-Hilbert space. We consider such construction in the linear order in the Riemann tensor and scalar curvature and also present an explicit form of interaction Lagrangians and gauge transformations for massive particles with spins 1 and 2 in terms of symmetrical tensor fields.Comment: 15 pages, latex, no figures,minor change

Direct evidence for a piezoelectriclike effect in coherently strained SiGe/Si heterostructures

A hybrid acoustic spectroscopy technique has been used to demonstrate the (reversible) conversion of high frequency electric fields into longitudinal acoustic waves within a modulation-doped pseudomorphic Si/Si0.88Ge0.12/Si heterostructure. This provides compelling evidence for the existence of a piezoelectriclike coupling within such structures

Correlation energy of an electron gas: a functional approach

Correlation effects of an electron gas in an external potential are derived using an Effective Action functional method. Corrections beyond the random phase approximation (RPA) are naturally incorporated by this method. The Effective Action functional is made to depend explicitly on two-point correlation functions. The calculation is carried out at imaginary time. For a homogeneous electron gas, we calculate the effect of exchange on the ring diagrams at zero temperature and show how to include some of the ladder diagrams. Our results agree well with known numerical calculations. We conclude by showing that this method is in fact a variant of the time dependent density functional method and suggest that it is suitable to be applied to the study of correlation effects in the non-homogeneous case.Comment: 20 figures numbered as in the tex

A Hybrid N-body--Coagulation Code for Planet Formation

We describe a hybrid algorithm to calculate the formation of planets from an initial ensemble of planetesimals. The algorithm uses a coagulation code to treat the growth of planetesimals into oligarchs and explicit N-body calculations to follow the evolution of oligarchs into planets. To validate the N-body portion of the algorithm, we use a battery of tests in planetary dynamics. Several complete calculations of terrestrial planet formation with the hybrid code yield good agreement with previously published calculations. These results demonstrate that the hybrid code provides an accurate treatment of the evolution of planetesimals into planets.Comment: Astronomical Journal, accepted; 33 pages + 11 figure

TREATMENT OF HYPERТENSIVE DISEASE WIТH GERMELON

Although the pathogenesis аnd the clinical pictuгe are so fаг well studied, hypertensive disease still presents some therapeutic difficulties.Thе alkaloids оf various species of hellebore have bееn applied since long in the treathment of this ailment (Veratrum viride, Veratrum album. Veratrum sabadille). Prepaгations used so far exhibited the disadvantage that effective therapeutic dose was quite close to the tохic оnе.Recently аn alkaloid complex with lower toxicity аnd а marked hypotensive effect was isolated fгom Veratrum lobelianum аnd offered for the tгеаtmеnt of  hyperrtensive disease. This alkaloid complex was applied under the name of Germelon in the fоrm of 0,2 mg tablets fог the tгeatment of hypertensive disease at the Chair of Propedeutics of lntеrnаl Medicine at the Higher Medical Institute in Varnа

An RBC model with investment-specific technological change: lessons for Bulgaria (1999–2018)

We introduce investment-specific technological change (ISTC) into an otherwise standard real-business-cycle setup with a government sector. We calibrate the model to Bulgarian data for the period following the introduction of the currency board arrangement (1999–2018). We then investigate the quantitative importance of the ISTC process in such a model for cyclical fluctuations in Bulgaria, and compare the results to a setup where cycles are driven by shocks to total factor productivity. We find that the model with ISTC shocks matches Bulgarian data better than the standard model driven by changes to total factor productivity only. The ISTC process is thus a better candidate for a a ”technology shock generation process,” at least in Bulgaria since the 2000s

The structure of Green functions in quantum field theory with a general state

In quantum field theory, the Green function is usually calculated as the expectation value of the time-ordered product of fields over the vacuum. In some cases, especially in degenerate systems, expectation values over general states are required. The corresponding Green functions are essentially more complex than in the vacuum, because they cannot be written in terms of standard Feynman diagrams. Here, a method is proposed to determine the structure of these Green functions and to derive nonperturbative equations for them. The main idea is to transform the cumulants describing correlations into interaction terms.Comment: 13 pages, 6 figure

A Unified Approach for the Enantioselective Synthesis of the Brominated Chamigrene Sesquiterpenes

The brominated chamigrene sesquiterpenes constitute a large subclass of bromocyclohexane‐containing natural products, yet no general enantioselective strategy for the synthesis of these small molecules exists. Herein we report a general strategy for accessing this family of secondary metabolites, including the enantioselective synthesis of (−)‐α‐ and (−)‐ent‐β‐bromochamigrene, (−)‐dactylone, and (+)‐aplydactone. Access to these molecules is enabled by a stereospecific bromopolyene cyclization initiated by the solvolysis of an enantiomerically enriched vicinal bromochloride.Dihalides light the way: A stereospecific bromopolyene cyclization of an enantiomerically enriched bromochloride was developed as a highly general approach to the brominated chamigrene sesquiterpenes (see scheme). The total synthesis of (+)‐aplydactone was completed by an intramolecular [2+2] cycloaddition.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137372/1/anie201605722.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137372/2/anie201605722_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137372/3/anie201605722-sup-0001-misc_information.pd