5,565 research outputs found
Light-cone Gauge Superstring Field Theory and Dimensional Regularization II
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
dimensions and define the amplitudes as analytic functions of . With an
appropriately chosen three-string interaction term and large negative , 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 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
We construct solitonic states in the OSp invariant string field theory, which
are BRST invariant in the leading order of regularization parameter .
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
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
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
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
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
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
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
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