Cosmological stabilization of moduli with steep potentials

A scenario which overcomes the well-known cosmological overshoot problem associated with stabilizing moduli with steep potentials in string theory is proposed. Our proposal relies on the fact that moduli potentials are very steep and that generically their kinetic energy quickly becomes dominant. However, moduli kinetic energy red-shifts faster than other sources when the universe expands. So, if any additional sources are present, even in very small amounts, they will inevitably become dominant. We show that in this case cosmic friction allows the dissipation of the large amount of moduli kinetic energy that is required for the field to be able to find an extremely shallow minimum. We present the idea using analytic methods and verify with some numerical examples.Comment: 15 pages, 5 figure

The entrepreneurial culture value patterns and business practices of small and medium enterprises in Sri Lanka based on selected case studies

Entrepreneurial cultural values of Small Medium Entrepreneurs play an important role in the development of entrepreneurs/lip development. This paper is to study the entrepreneur value patterns and their business practices in Sri Lanka. This is a descriptive study and the analysis is qualitative based on Ten Textile and Jewelry- Trades in the City of Colombo and for the data collection a structural questionnaire was administered and personal inten'icws were conducted. It was found that the entrepreneurial cultural value system and their business practices are different from that of western entrepreneurs. The common business related practices found to be seen personalized leadership, centralized decision making, reluctant to delegate authority, informal recruitment policy, specific local market orientation, not using modern financial facilities and direct supervisions are based on their entrepreneurial values such as low initiatives, low risk tolerance, low level openness, medium level conflict tolerance and medium level supportiveness. However, the successful entrepreneurs' business practices such as benevolent authoritarian leadership, decentralized decision making, delegating authority to others, and expanding their local markets are highly influenced by their loyalty, medium openness, initiatives and risk tolerance and high conflict tolerance. Besides the researcher has found that there is a link between the background factors and the value systems of entrepreneurs. Therefore it gives new idea for the futureEntrepreneurial cultural values of Small Medium Entrepreneurs play an important role in the development of entrepreneurs/lip development. This paper is to study the entrepreneur value patterns and their business practices in Sri Lanka. This is a descriptive study and the analysis is qualitative based on Ten Textile and Jewelry- Trades in the City of Colombo and for the data collection a structural questionnaire was administered and personal inten'icws were conducted. It was found that the entrepreneurial cultural value system and their business practices are different from that of western entrepreneurs. The common business related practices found to be seen personalized leadership, centralized decision making, reluctant to delegate authority, informal recruitment policy, specific local market orientation, not using modern financial facilities and direct supervisions are based on their entrepreneurial values such as low initiatives, low risk tolerance, low level openness, medium level conflict tolerance and medium level supportiveness. However, the successful entrepreneurs' business practices such as benevolent authoritarian leadership, decentralized decision making, delegating authority to others, and expanding their local markets are highly influenced by their loyalty, medium openness, initiatives and risk tolerance and high conflict tolerance. Besides the researcher has found that there is a link between the background factors and the value systems of entrepreneurs. Therefore it gives new idea for the futureEntrepreneurial cultural values of Small Medium Entrepreneurs play an important role in the development of entrepreneurs/lip development. This paper is to study the entrepreneur value patterns and their business practices in Sri Lanka. This is a descriptive study and the analysis is qualitative based on Ten Textile and Jewelry- Trades in the City of Colombo and for the data collection a structural questionnaire was administered and personal inten'icws were conducted. It was found that the entrepreneurial cultural value system and their business practices are different from that of western entrepreneurs. The common business related practices found to be seen personalized leadership, centralized decision making, reluctant to delegate authority, informal recruitment policy, specific local market orientation, not using modern financial facilities and direct supervisions are based on their entrepreneurial values such as low initiatives, low risk tolerance, low level openness, medium level conflict tolerance and medium level supportiveness. However, the successful entrepreneurs' business practices such as benevolent authoritarian leadership, decentralized decision making, delegating authority to others, and expanding their local markets are highly influenced by their loyalty, medium openness, initiatives and risk tolerance and high conflict tolerance. Besides the researcher has found that there is a link between the background factors and the value systems of entrepreneurs. Therefore it gives new idea for the future researchers

A Comparison of Supersymmetry Breaking and Mediation Mechanisms

We give a unified treatment of different models of supersymmetry breaking and mediation from a four dimensional effective field theory standpoint. In particular a comparison between GMSB and various gravity mediated versions of SUSY breaking shows that, once the former is embedded within a SUGRA framework, there is no particular advantage to that mechanism from the point of view of FCNC suppression. We point out the difficulties of all these scenarios - in particular the cosmological modulus problem. We end with a discussion of possible string theory realizations.Comment: Added clarifications and references, 20 page

Constraints on LVS Compactifications of IIB String Theory

We argue that once all theoretical and phenomenological constraints are imposed on the different versions of the Large Volume Scenario (LVS) compactifications of type IIB string theory, one particular version is favored. This is essentially a sequestered one in which the soft terms are generated by Weyl anomaly and RG running effects. We also show that arguments questioning sequestering in LVS models are not relevant in this case.Comment: 14 pages, additional discussion of D7 brane case and mSUGRA, reference adde

Dimensional reduction from entanglement in Minkowski space

Using a quantum field theoretic setting, we present evidence for dimensional reduction of any sub-volume of Minkowksi space. First, we show that correlation functions of a class of operators restricted to a sub-volume of D-dimensional Minkowski space scale as its surface area. A simple example of such area scaling is provided by the energy fluctuations of a free massless quantum field in its vacuum state. This is reminiscent of area scaling of entanglement entropy but applies to quantum expectation values in a pure state, rather than to statistical averages over a mixed state. We then show, in a specific case, that fluctuations in the bulk have a lower-dimensional representation in terms of a boundary theory at high temperature.Comment: 9 pages, changes to presentation, some content corrections, version published in JHE

The Problem of Time and Quantum Black Holes

We discuss the derivation of the so-called semi-classical equations for both mini-superspace and dilaton gravity. We find that there is no systematic derivation of a semi-classical theory in which quantum mechanics is formulated in a space-time that is a solution of Einstein's equation, with the expectation value of the matter stress tensor on the right-hand side. The issues involved are related to the well-known problems associated with the interpretation of the Wheeler-deWitt equation in quantum gravity, including the problem of time. We explore the de Broglie-Bohm interpretation of quantum mechanics (and field theory) as a way of spontaneously breaking general covariance, and thereby giving meaning to the equations that many authors have been using to analyze black hole evaporation. We comment on the implications for the ``information loss" problem.Comment: 30 pages, COLO-HEP-33

Black Hole Formation by Sine-Gordon Solitons in Two-dimensional Dilaton Gravity

The CGHS model of two-dimensional dilaton gravity coupled to a sine-Gordon matter field is considered. The theory is exactly solvable classically, and the solutions of a kink and two-kink type solitons are studied in connection with black hole formation.Comment: 11 pages, no figures, revte

Hamiltonian Approach to 2D Dilaton-Gravities and Invariant Adm Mass

The formula existing in the literature for the ADM mass of 2D dilaton gravity is incomplete. For example, in the case of an infalling matter shockwave this formula fails to give a time-independent mass, unless a very special coordinate system is chosen. We carefully carry out the canonical formulation of 2D dilaton gravity theories (classical, CGHS and RST). As in 4D general relativity one must add a boundary term to the bulk Hamiltonian to obtain a well-defined variational problem. This boundary term coincides with the numerical value of the Hamiltonian and gives the correct mass which obviously is time-independent.Comment: revised, 12 pages, PUPT-1379; we added a reference and corrected some minor typo