Torsion constraints in supergeometry

We derive the torsion constraints for superspace versions of supergravity theories by means of the theory ofG-structures. We also discuss superconformal geometry and superKähler geometry.Permanent address as of September 1, 1990: Department of Mathematics, University of Michigan, Ann Arbor, MI 48109, USA     

Measured Spectral Amplitude of Lightning Sferics in the HF, VHF, and UHF Bands

An experimental study was carried out to measure the spectral amplitude of lightning sferics at 22.5 MHz, 225 MHz, and 2.25 GHz. This effort included the detection, storage, and analysis of RF emission data to determine accurately the relative electric-field strength produced by the lightning associated with a typical local thunderstorm. These measured spectral amplitudes are normalized and plotted relative to similar data from other investigators. These data support a l/f2 to 11f3 slope for sferics at frequencies above the HF range.     

Remark about heat diffusion on periodic spaces

Let be a complete Riemannian manifold with a free cocompact -action. Let be the heat kernel on . We compute the asymptotics of in the limit in which and . We show that in this limit, the heat diffusion is governed by an effective Euclidean metric on coming from the Hodge inner product on .

     

Some Geometric Calculations on Wasserstein Space

We compute the Riemannian connection and curvature for the Wasserstein space of a smooth compact Riemannian manifold. This research was partially supported by NSF grant DMS-0604829.     

Automated Generation of Microkinetics for Heterogeneously Catalyzed Reactions Considering Correlated Uncertainties**

The study presents an ab-initio based framework for the automated construction of microkinetic mechanisms considering correlated uncertainties in all energetic parameters and estimation routines. 2000 unique microkinetic models were generated within the uncertainty space of the BEEF-vdW functional for the oxidation reactions of representative exhaust gas emissions from stoichiometric combustion engines over Pt(111) and compared to experiments through multiscale modeling. The ensemble of simulations stresses the importance of considering uncertainties. Within this set of first-principles-based models, it is possible to identify a microkinetic mechanism that agrees with experimental data. This mechanism can be traced back to a single exchange-correlation functional, and it suggests that Pt(111) could be the active site for the oxidation of light hydrocarbons. The study provides a universal framework for the automated construction of reaction mechanisms with correlated uncertainty quantification, enabling a DFT-constrained microkinetic model optimization for other heterogeneously catalyzed systems.