Range Separated Brueckner Coupled Cluster Doubles Theory

We introduce a range-separation approximation to coupled cluster doubles (CCD) theory that successfully overcomes limitations of regular CCD when applied to the uniform electron gas. We combine the short-range ladder channel with the long-range ring channel in the presence of a Bruckner renormalized one-body interaction and obtain ground-state energies with an accuracy of 0.001 a.u./electron across a wide range of density regimes. Our scheme is particularly useful in the low-density and strongly-correlated regimes, where regular CCD has serious drawbacks. Moreover, we cure the infamous overcorrelation of approaches based on ring diagrams (i.e. the particle-hole random phase approximation). Our energies are further shown to have appropriate basis set and thermodynamic limit convergence, and overall this scheme promises energetic properties for realistic periodic and extended systems which existing methods do not possess.Comment: 5 pages, 3 figs. Now with supplementary info. Comments welcome: [email protected]

Determination of complex absorbing potentials from the electron self-energy

The electronic conductance of a molecule making contact to electrodes is determined by the coupling of discrete molecular states to the continuum electrode density of states. Interactions between bound states and continua can be modeled exactly by using the (energy-dependent) self-energy, or approximately by using a complex potential. We discuss the relation between the two approaches and give a prescription for using the self-energy to construct an energy-independent, non-local, complex potential. We apply our scheme to studying single-electron transmission in an atomic chain, obtaining excellent agreement with the exact result. Our approach allows us to treat electron-reservoir couplings independent of single electron energies, allowing for the definition of a one-body operator suitable for inclusion into correlated electron transport calculations.Comment: 11 pages, 8 figures; to be published in the J. Chem. Phy

On the Assouad dimension of self-similar sets with overlaps

It is known that, unlike the Hausdorff dimension, the Assouad dimension of a self-similar set can exceed the similarity dimension if there are overlaps in the construction. Our main result is the following precise dichotomy for self-similar sets in the line: either the \emph{weak separation property} is satisfied, in which case the Hausdorff and Assouad dimensions coincide; or the \emph{weak separation property} is not satisfied, in which case the Assouad dimension is maximal (equal to one). In the first case we prove that the self-similar set is Ahlfors regular, and in the second case we use the fact that if the \emph{weak separation property} is not satisfied, one can approximate the identity arbitrarily well in the group generated by the similarity mappings, and this allows us to build a \emph{weak tangent} that contains an interval. We also obtain results in higher dimensions and provide illustrative examples showing that the `equality/maximal' dichotomy does not extend to this setting.Comment: 24 pages, 2 figure

Corporate Heroin: A Defense of Perks, Executive Loans, and Conspicuous Consumption

We argue that firms undertake to reduce employee savings in order to avoid final period problems that occur when employees accumulate enough wealth to retire and leave the industry. Normally, reputation constrains employee behavior, since an employee who cheats at one firm will then find herself unable to get a job at another However, employees who have saved such that they no longer care about continued employment will act opportunistically in the final periods of employment, which can destroy much or all of the surplus otherwise created by the employment relationship. We believe that this sort of final period cheating creates significant problems for employees in positions of delicate trust, particularly those with a large variable compensation component, such as corporate CEOs, securities professionals, and even corporate lawyers. Payment-in-kind (perks), deferred compensation (corporate loans), and the encouragement of employees\u27 conspicuous consumption-through screening, inculcation, or signaling-are strategies that firms enact to combat this final period problem of employee cheating. Employees who reduce savings are more reliable over the long term than employees who do not, since reduced savings makes employees more dependent upon remaining employed into the future; these employees will invest in their reputations by engaging in less cheating. We make an analogy to drug dependency: The employee who consumes all her resources immediately enjoys large present utility, as does the addict, but is ultimately dependent on the firm to provide her with the same opportunities in the future. Applying the theoretical framework we develop to the real world can help explain much of observable behavior and compensation practice. Thus, far from being prima facie evidence of corporate fraud-the picture painted by the media, academia, and prosecutors at recent corporate trials--high levels of in-kind compensation, corporate loans, and personal consumption may be evidence of optimal incentivization, where principal and agent have contracted (explicitly or implicitly) for just the amount and type of remuneration that maximizes their joint welfare

Forestry in Louisiana - The Industrys Contribution to the Louisiana Economy: An Input-Output Analysis 2011 (Research Information Sheet #

Forest resources affect the economy at all levels, from wages and purchases in local economies to state-level payroll and income taxes. Therefore, there is widespread interest in effects of the forest products industry from local producers, landowners and multinational corporate entities and therefore political officials, as well. This study evaluates the importance of the forest products industry to the state’s economy.https://digitalcommons.lsu.edu/agcenter_researchinfosheets/1004/thumbnail.jp

The Theological Dimension of Community Life

xvi, 431 hal; 23,5 c