Per Berglund Professor of Physics travels to Germany

The CIE grant provided financial support to travel in May 2013 to Hamburg, Germany to visit DESY, the German Electron Synchrotron, one of the world\u27s leading particle accelerators used to study the fundamental constituents of nature and their interactions. My local expenses were covered by a Collaborative Research Center (SFB) fellowship that I was awarded through SFB’s 676 Particle, Strings and the Early Universe--The Structure of Matter and Space-Time hosted by DESY and the University of Hamburg. Together these awards facilitated two months of visits and collaborations with theoretical physicists at DESY in 2013

Stringy corrections to Kahler potentials, SUSY breaking, and the cosmological constant problem

The moduli of N=1 compactifications of IIB string theory can be stabilized by a combination of fluxes (which freeze complex structure moduli and the dilaton) and nonperturbative superpotentials (which freeze Kahler moduli), typically leading to supersymmetric AdS vacua. We show that stringy corrections to the Kahler potential qualitatively alter the structure of the effective scalar potential even at large volume, and can give rise to non-supersymmetric vacua including metastable de Sitter spacetimes. Our results suggest an approach to solving the cosmological constant problem, so that the scale of the 1-loop corrected cosmological constant can be much smaller than the scale of supersymmetry breaking.Comment: LaTeX, 2 EPS figures. If you use mpage on a Unix machine to print multiple pages on a single sheet you may experience problems printing the figures. v3: corrections and comments in cosmological constant sectio

Multi-Field Inflation from String Theory

We construct a multi-field inflationary model consisting of multiple K\"ahler moduli derived from type IIB string compactification in the large volume limit. The model consists of both heavy and light fields, with the former being frozen during the inflationary period and the latter acting as the inflaton(s). We study the evolution of all the fields during and after inflation until the preheating era when all the fields oscillate around their vacuum expectation values. Our numerical analysis shows that the curvature perturbations have an almost scale invariant power spectrum with $n_s \simeq 0.96$.Comment: 25 pages, 17 figure

Extent and Distribution of Urban Tax Delinquency

Purpose – Work-place learning takes place in many settings and in different ways, resulting in knowledge and skills of different kinds. The recognition process in the work place is however often implicit and seldom discussed in terms of recognition of prior learning (RPL). The aim of this paper is to give examples of how the knowledge/skills of employees get recognition in the workplace and to discuss what the consequences of such recognition processes might be. Design/methodology/approach – This paper is based on a study in two companies and two municipalities, where 21 interviews were conducted with human resource managers, team leaders and union representatives. The research questions concerned the ways skills were recognised among employees and how the logics of these actions could be understood. Findings – The findings show that both companies and municipalities have their own ways of assessing knowledge/skills, mostly out of a production logic of what is needed at the workplace. However, certain skills are also made “unvisualised” for the employee. This employer-controlled recognition logic is important to understand when RPL models are brought to the work place in order to obtain win-win situations for both employers and employees. Practical implications – It seems important to identify an already existing system for assessment of knowledge/skills at the workplace when bringing RPL processes to the workplace. Originality/value – The approach to understand assessment processes in these companies and municipalities from an RPL perspective has not been widely covered before

Non-Gaussianity in String Cosmology: A Case Study

We study non-gaussianity effects, using the $\delta N$ formalism, in a multi-field inflationary model consisting of K\"ahler moduli derived from type IIB string compactification in the large volume limit. The analytical work in this paper mostly follows the separable potential method developed by Vernizzi and Wands. The numerical analysis is then used in computing non-gaussianity beyond slow-roll regime. The possibility of the curvaton scenario is also discussed. We give the condition for the existence of the curvaton and calculate the non-guassianity generated by the curvaton decay in the large volume limit.Comment: 25 page

Exploring transaminase stability for biocatalysis

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The AdS/CFT correspondence and Spectrum Generating Algebras

We list the spectrum generating algebras for string theory and M-theory compactified on various backgrounds of the form $AdS_{d+1} \times S^n$. We identify the representations of these algebras which make up the classical supergravity spectra and argue for the presence of these spectrum generating algebras in the classical string/M-theory. We also discuss the role of the spectrum generating algebras on the conformal field theory side.Comment: 17 pages, 4 Tables, harvma