5,565 research outputs found

    Light-cone Gauge Superstring Field Theory and Dimensional Regularization II

    Get PDF
    We propose a dimensional regularization scheme to deal with the divergences caused by colliding supercurrents inserted at the interaction points, in the light-cone gauge NSR superstring field theory. We formulate the theory in dd dimensions and define the amplitudes as analytic functions of dd. With an appropriately chosen three-string interaction term and large negative dd, the tree level amplitudes for the (NS,NS) closed strings can be recast into a BRST invariant form, using the superconformal field theory proposed in Ref.[arXiv:0911.3704]. We show that in the limit d→10d \to 10 they coincide with the results of the first quantized theory. Therefore we obtain the desired results without adding any contact interaction terms to the action.Comment: 23 pages; v2: minor modifications; v3: revised argument in section 3, added appendix C, results unchanged; v4: added clarifications, two figures and a footnote; v5: minor modification

    D-brane States and Disk Amplitudes in OSp Invariant Closed String Field Theory

    Full text link
    We construct solitonic states in the OSp invariant string field theory, which are BRST invariant in the leading order of regularization parameter ϵ\epsilon. We calculate the disk amplitudes using these solitonic states and show that they describe D-branes and ghost D-branes.Comment: 37 pages, 8 figure

    Spacetime Fermions in Light-cone Gauge Superstring Field Theory and Dimensional Regularization

    Get PDF
    We consider the dimensional regularization of the light-cone gauge type II superstring field theories in the NSR formalism. In the previous work, we have calculated the tree-level amplitudes with external lines in the (NS,NS) sector using the regularization and shown that the desired results are obtained without introducing contact term interactions. In this work, we study the tree-level amplitudes with external lines in the Ramond sector. In order to deal with them, we propose a worldsheet theory to be used instead of that for the naive dimensional regularization. With the worldsheet theory, we regularize and define the tree-level amplitudes by analytic continuation. We show that the results coincide with those of the first quantized formulation.Comment: 28 pages, 5 figures; v2: more details of our manipulations in subsection 3.2 added, figures and references added; v3: clarifications adde

    Light-cone Gauge NSR Strings in Noncritical Dimensions II -- Ramond Sector

    Get PDF
    Light-cone gauge superstring theory in noncritical dimensions corresponds to a worldsheet theory with nonstandard longitudinal part in the conformal gauge. The longitudinal part of the worldsheet theory is a superconformal field theory called X^{\pm} CFT. We show that the X^{\pm} CFT combined with the super-reparametrization ghost system can be described by free variables. It is possible to express the correlation functions in terms of these free variables. Bosonizing the free variables, we construct the spin fields and BRST invariant vertex operators for the Ramond sector in the conformal gauge formulation. By using these vertex operators, we can rewrite the tree amplitudes of the noncritical light-cone gauge string field theory, with external lines in the (R,R) sector as well as those in the (NS,NS) sector, in a BRST invariant way.Comment: 33 pages; v2: minor modification

    Matrix Model For Polyakov Loops, String Field Theory In The Temporal Gauge, Winding String Condensation In Anti-de Sitter Space And Field Theory Of D-branes

    Full text link
    Closed string field theory is constructed by stochastically quantizing a matrix model for Polyakov loops that describes phases of a large N gauge theory at finite temperature. Coherent states in this string field theory describes winding string condensation which has been expected to cause a topology change from thermal AdS geometry to AdS-Schwarzschild black hole geometry. D-branes in this closed string field theory is also discussed. Slightly extended version of a talk given at CosPA 2007, Nov.13-15, Taipei, Taiwan.Comment: Slightly extended version of a talk given at CosPA 2007, Nov.13-15, Taipei, Taiwan; 14 page

    Household dynamics and small timber consumption in rural Kashmir (J&K), India

    Get PDF
    The study examined the extraction and consumption pattern of small timber and its socioeconomic and forest resource determinants among the rural people in district Ganderbal of Kashmir. The results showed that the total extraction of small timber from different sources in the sample villages was 39.46 tons annum-1, which is mostly consumed in housing and roofing (39.63%) followed by cattle shed/ store house (15.25%), rural furniture/ packing cases (14.75%), agricultural implements (13.25%), fencing (12.50%) and others (4.62%). The total small timber demand was 47.88 m3 annum-1, which is mostly procured from agroforestry (42.57%) followed by forests (26.09%), homestead forestry (17.05%) and social/ community forestry (14.29%). The people were destitute with respect to socioeconomic attributes while they are well-off regarding forest resource characteristics. Correlation and multiple regression analysis established a robust relationship between small timber consumption and socioeconomic and forest resource parameters. The small timber flow from forests to the sample villages is excessive as compared to the national estimates, creating threats to the biodiversity conservation and ecological stability of the adjoining forests. The over-utilization of forest biomass by the local people is leading to degradation of forest resources and diminished biomass productivity, which in turn induce socioeconomic and livelihood stress. Therefore, some alternative interventions are essential to be implemented efficiently to keep pace with current development and future challenges

    Deterministic meeting of sniffing agents in the plane

    Full text link
    Two mobile agents, starting at arbitrary, possibly different times from arbitrary locations in the plane, have to meet. Agents are modeled as discs of diameter 1, and meeting occurs when these discs touch. Agents have different labels which are integers from the set of 0 to L-1. Each agent knows L and knows its own label, but not the label of the other agent. Agents are equipped with compasses and have synchronized clocks. They make a series of moves. Each move specifies the direction and the duration of moving. This includes a null move which consists in staying inert for some time, or forever. In a non-null move agents travel at the same constant speed, normalized to 1. We assume that agents have sensors enabling them to estimate the distance from the other agent (defined as the distance between centers of discs), but not the direction towards it. We consider two models of estimation. In both models an agent reads its sensor at the moment of its appearance in the plane and then at the end of each move. This reading (together with the previous ones) determines the decision concerning the next move. In both models the reading of the sensor tells the agent if the other agent is already present. Moreover, in the monotone model, each agent can find out, for any two readings in moments t1 and t2, whether the distance from the other agent at time t1 was smaller, equal or larger than at time t2. In the weaker binary model, each agent can find out, at any reading, whether it is at distance less than \r{ho} or at distance at least \r{ho} from the other agent, for some real \r{ho} > 1 unknown to them. Such distance estimation mechanism can be implemented, e.g., using chemical sensors. Each agent emits some chemical substance (scent), and the sensor of the other agent detects it, i.e., sniffs. The intensity of the scent decreases with the distance.Comment: A preliminary version of this paper appeared in the Proc. 23rd International Colloquium on Structural Information and Communication Complexity (SIROCCO 2016), LNCS 998

    Working capital management and financial performance of listed conglomerate companies in Nigeria

    Get PDF
    This study examines the impact of working capital management on the financial performance of listed conglomerate companies in Nigeria for a period of ten (10) years (2005-2014). Data for the study were quantitatively retrieved from the annual reports and accounts of the studied companies. The study employed descriptive statistics to describe the variable while the relationships among the variables were established via correlation. Variable Inflation Factor (VIF) was used to determine the existence or otherwise of multi-collinearity while Ordinary Least Square (OLS) Regression was used to analyze the data. It was found that debtors collection period, creditors payment period and firm size were negatively related to return on investment while cash conversion cycle has positive but insignificant relationship with the financial performance of the studied companies. The study however, recommends among others that listed conglomerate companies should maintain the current debtors’ collection period or further reduce it in order to continue to enhance financial performance.peer-reviewe
    • …
    corecore