Otto Hesse / in moderner Rechtschreibung neu hrsg. von Gabriele Dörflinger, Universitätsbibliothek Heidelberg

Biographie des Mathematikers Otto Hesse (1811-1874), der von 1856 bis 1868 an der Heidelberger Universität lehrte. Die Originalbiographie wurde in der vor 1900 gültigen Rechtschreibung publiziert. Die Neuausgabe benutzt die aktuelle Rechtschreibung

On the finite generation of additive group invariants in positive characteristic

Roberts, Freudenburg, and Daigle and Freudenburg have given the smallest counterexamples to Hilbert's fourteenth problem as rings of invariants of algebraic groups. Each is of an action of the additive group on a finite dimensional vector space over a field of characteristic zero, and thus, each is the kernel of a locally nilpotent derivation. In positive characteristic, additive group actions correspond to locally finite iterative higher derivations. We set up characteristic-free analogs of the three examples, and show that, contrary to characteristic zero, in every positive charateristic, the invariants are finitely generated.Comment: added a missing reference and a new section with an extension of the main result, corrected some typos, 14 page

Dynamical Hartree-Fock-Bogoliubov Theory of Vortices in Bose-Einstein Condensates at Finite Temperature

We present a method utilizing the continuity equation for the condensate density to make predictions of the precessional frequency of single off-axis vortices and of vortex arrays in Bose-Einstein condensates at finite temperature. We also present an orthogonalized Hartree-Fock-Bogoliubov (HFB) formalism. We solve the continuity equation for the condensate density self-consistently with the orthogonalized HFB equations, and find stationary solutions in the frame rotating at this frequency. As an example of the utility of this formalism we obtain time-independent solutions for quasi-two-dimensional rotating systems in the co-rotating frame. We compare these results with time-dependent predictions where we simulate stirring of the condensate.Comment: 13 pages, 11 figures, 1 tabl

Noether's theorem and gauge transformations. Application to the bosonic string and CP(2,n-1) model

New results on the theory of constrained systems are applied to characterize the generators of Noethers symmetry transformations. As a byproduct, an algorithm to construct gauge transformations in Hamiltonian formalism is derived. This is illustrated with two relevant examples

How Leaders Use the Construct of Culture to Influence Change Resistance: A Study of a Planned Change Initiative in a Combined Government and Military Organization

The construct of organizational culture has been used to interpret various aspects of organizational life, including organizational leadership and organizational change. The literature indicates that leaders can influence organizational change by attending to and modifying an organization\u27s cultural dimensions. Much of this literature, however, is theoretical and speculative, and the empirical work that does exist has focused mostly on business. The purpose of this case study was to develop an understanding of how leaders in a combined government and military organization used the notion of culture during a two-and-a-half year planned change initiative. The study explored the strategies and mental constructs those in positions of formal authority used to make sense of and influence the change process. The particular focus was on identifying any culture-oriented change strategies leaders use to overcome resistance to change. The study also examined how organizational culture shaped and constrained leaders\u27 actions. This study employed qualitative methods. Interviews with designated leaders of the planned change initiative were the primary data collection method. Document analysis and participant observation were used to triangulate interview data. Several findings and conclusions emerged from the study. One of the more interesting findings involved the observation of resistance at the top of the organizational hierarchy, i.e. the level from which the change initiative had been promoted. Normally, resistance is conceptualized as something that occurs at the bottom rungs of an organizational hierarchy. In this initiative, in which middle managers were given considerable authority about what would be done to achieve goals mandated from the top, there was significant resistance coming from above as well as below. Both levels, in other words, were uncomfortable with the specific cultural change being implemented, and both levels attempted to minimize its impact. This study should be useful to individuals who are charged with leading large-scale change initiatives within their organizations and to scholars who analyze and write about the use of culture as both a facilitating and an inhibiting factor in planned organizational change

Broken Time Translation Symmetry as a model for Quantum State Reduction

The symmetries that govern the laws of nature can be spontaneously broken, enabling the occurrence of ordered states. Crystals arise from the breaking of translation symmetry, magnets from broken spin rotation symmetry and massive particles break a phase rotation symmetry. Time translation symmetry can be spontaneously broken in exactly the same way. The order associated with this form of spontaneous symmetry breaking is characterised by the emergence of quantum state reduction: systems which spontaneously break time translation symmetry act as ideal measurement machines. In this review the breaking of time translation symmetry is first compared to that of other symmetries such as spatial translations and rotations. It is then discussed how broken time translation symmetry gives rise to the process of quantum state reduction and how it generates a pointer basis, Born's rule, etc. After a comparison between this model and alternative approaches to the problem of quantum state reduction, the experimental implications and possible tests of broken time translation symmetry in realistic experimental settings are discussed.Comment: 15 pages, 5 figure

Bibliography on contemporary Italy

Caption titleHandwritten on leaf [1]: L2-319. C/53-5. Econ. DevAt head of title: Italy. Bibl/1. Jan. 26,1953. E.P. Noethe

Jakob Lüroth / neu hrsg. von Gabriele Dörflinger, Universitätsbibliothek Heidelberg

Nachruf auf den vielseitigen Mathematiker Jakob Lüroth (1844-1910), der 1867/68 in Heidelberg lehrte. 1869 wurde er in Karlsruhe ordentlicher Professor und folgte 1880 einem Ruf an die Technische Hochschule in München. Enthält ein Verzeichnis der Schriften Lüroths

Preference symmetries, partial differential equations, and functional forms for utility

A discrete symmetry of a preference relation is a mapping from the domain of choice to itself under which preference comparisons are invariant; a continuous symmetry is a one-parameter family of such transformations that includes the identity; and a symmetry field is a vector field whose trajectories generate a continuous symmetry. Any continuous symmetry of a preference relation implies that its representations satisfy a system of PDEs. Conversely the system implies the continuous symmetry if the latter is generated by a field. Moreover, solving the PDEs yields the functional form for utility equivalent to the symmetry. This framework is shown to encompass a variety of representation theorems related to univariate separability, multivariate separability, and homogeneity, including the cases of Cobb–Douglas and CES utilityr. The work reported here was supported by a research fellowship from Nuffield College, Oxfor

Nonlinear Transformation for a Class of Gauged Schroedinger Equations with Complex Nonlinearities

In the present contribution we consider a class of Schroedinger equations containing complex nonlinearities, describing systems with conserved norm $|\psi|^2$ and minimally coupled to an abelian gauge field. We introduce a nonlinear transformation which permits the linearization of the source term in the evolution equations for the gauge field, and transforms the nonlinear Schroedinger equations in another one with real nonlinearities. We show that this transformation can be performed either on the gauge field $A_\mu$ or, equivalently, on the matter field $\psi$. Since the transformation does not change the quantities $|\psi|^2$ and $F_{\mu\nu}$, it can be considered a generalization of the gauge transformation of third kind introduced some years ago by other authors. Pacs numbers: 03.65.-w, 11.15.-qComment: 4pages, two columns, RevTeX4, no figure