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43
Distributions of flux vacua
 JHEP
"... Abstract: We give results for the distribution and number of flux vacua of various types, supersymmetric and nonsupersymmetric, in IIb string theory compactified on CalabiYau manifolds. We compare this with related problems such as counting attractor points. Contents ..."
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Cited by 115 (17 self)
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Abstract: We give results for the distribution and number of flux vacua of various types, supersymmetric and nonsupersymmetric, in IIb string theory compactified on CalabiYau manifolds. We compare this with related problems such as counting attractor points. Contents
Building a better racetrack
 JHEP 0406
"... We find IIb compactifications on CalabiYau orientifolds in which all Kähler moduli are stabilized, along lines suggested by Kachru, Kallosh, Linde and Trivedi. ..."
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Cited by 81 (7 self)
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We find IIb compactifications on CalabiYau orientifolds in which all Kähler moduli are stabilized, along lines suggested by Kachru, Kallosh, Linde and Trivedi.
Generic Rules For High Temperature Dimensional Reduction And Their Application To The Standard Model
, 1995
"... We formulate the rules for dimensional reduction of a generic finite temperature gauge theory to a simpler threedimensional effective bosonic theory in terms of a matching of Green's functions in the full and the effective theory, and present a computation of a generic set of 1 and 2loop graphs n ..."
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Cited by 19 (5 self)
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We formulate the rules for dimensional reduction of a generic finite temperature gauge theory to a simpler threedimensional effective bosonic theory in terms of a matching of Green's functions in the full and the effective theory, and present a computation of a generic set of 1 and 2loop graphs needed for the application of these rules. As a concrete application we determine the explicit mapping of the physical parameters of the standard electroweak theory to a threedimensional SU(2)\ThetaU(1) gaugeHiggs theory. We argue that this threedimensional theory has a universal character and appears as an effective theory for many extensions of the Standard Model. 1 kajantie@phcu.helsinki.fi 2 mlaine@phcu.helsinki.fi 3 kari@trek.physics.indiana.edu 4 mshaposh@nxth04.cern.ch 1 Introduction The properties of matter at high temperature are interesting for a number of experimental and cosmological applications. QCD at high temperature and density may be relevant for heavy ion colli...
Effective Tachyonic Potential in Closed String Field Theory
 Nucl. Phys. B
, 1995
"... We calculate the effective tachyonic potential in closed string field theory up to the quartic term in the tree approximation. This involves an elementary fourtachyon vertex and a sum over the infinite number of Feynman graphs with an intermediate massive state. We show that both the elementary ter ..."
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Cited by 16 (0 self)
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We calculate the effective tachyonic potential in closed string field theory up to the quartic term in the tree approximation. This involves an elementary fourtachyon vertex and a sum over the infinite number of Feynman graphs with an intermediate massive state. We show that both the elementary term and the sum can be evaluated as integrals of some measure over different regions in the moduli space of fourpunctured spheres. We show that both elementary and effective coupling give negative contributions to the quartic term in the tachyon potential. Numerical calculations show that the fourth order term is big enough to destroy a local minimum which exists in the third order approximation.
Machine Tongues XV: Three Packages for Software Sound Synthesis
 Computer Music Journal
"... This article will discuss the technology of SWSS and then present and compare these three systems. It is divided into three parts; the first introduces SWSS in terms of progressive examples. Part two compares the three systems using the same two instrument/score examples written in each of them. The ..."
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Cited by 15 (4 self)
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This article will discuss the technology of SWSS and then present and compare these three systems. It is divided into three parts; the first introduces SWSS in terms of progressive examples. Part two compares the three systems using the same two instrument/score examples written in each of them. The final section presents informal benchmark tests of the systems run on two different hardware platformsa Sun Microsystems SPARCstation2 IPX and a Next Computer Inc. TurboCube machineand subjective comments on various features of the languages and programming environments of stateoftheart SWSS software. This author's connection with this topic is that of extensive experience with several different SWSS systems over the last 15 years, starting with MUS10 and including all three compared here: Csound (in the form of Music11 initially) at the CMRS studio in Salzburg (Pope 1982); cmusic in the CARL environment at PCS/Cadmus computers in Munich (Pope 1986); and more recently a combination of cmix, Csound, and various vocoder software packages with user interfaces written in Smalltalk80 at the CCRMA Center for Computer Research in Music and Acoustics at Stanford University (Pope 1992).
Scheduling Tertiary I/O in Database Applications
 IN PROC. OF THE 8TH INTERNATIONAL WORKSHOP ON DATABASE AND EXPERT SYSTEMS APPLICATIONS
, 1997
"... We study the problem of scheduling I/O requests for tertiary storage libraries to improve performance. The focus is on scheduling policies that process all requests on a loaded medium before unloading it. For single drive settings an efficient algorithm that produces optimal schedules is developed. ..."
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Cited by 13 (3 self)
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We study the problem of scheduling I/O requests for tertiary storage libraries to improve performance. The focus is on scheduling policies that process all requests on a loaded medium before unloading it. For single drive settings an efficient algorithm that produces optimal schedules is developed. For multiple drives the problem is shown to be NPComplete. Efficient and effective heuristics are presented for the multiple drives case. The scheduling policies developed achieve significant performance gains over more naive first come first server policies. The study is general enough to be applicable to any storage library handling removable media, such as tapes or optical disks.
Inflationary Constraints on Type IIA String Theory
 Rev. D
"... We prove that inflation is forbidden in the most well understood class of semirealistic type IIA string compactifications: CalabiYau compactifications with only standard NSNS 3form flux, RR fluxes, D6branes and O6planes at large volume and small string coupling. With these ingredients, the fi ..."
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Cited by 9 (1 self)
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We prove that inflation is forbidden in the most well understood class of semirealistic type IIA string compactifications: CalabiYau compactifications with only standard NSNS 3form flux, RR fluxes, D6branes and O6planes at large volume and small string coupling. With these ingredients, the first slowroll parameter satisfies ǫ ≥ 27 13 whenever V> 0, ruling out both inflation (including brane/antibrane inflation) and de Sitter vacua in this limit. Our proof is based on the dependence of the 4dimensional potential on the volume and dilaton moduli in the presence of fluxes and branes. We also describe broader classes of IIA models which may include cosmologies with inflation and de Sitter vacua. The inclusion of extra ingredients, such as NS 5branes and geometric or nongeometric NSNS fluxes, evades the assumptions used in deriving the nogo theorem. We focus on NS 5branes and outline how such ingredients may prove fruitful for cosmology, but we do not provide an explicit model. We contrast the results of our IIA analysis with the rather different situation in IIB. Electronic address: mphertz at mit.edu
Parameter estimation for a mathematical model of the cell cycle in frog eggs
 Journal of Computational Biology
, 2005
"... Parameter values for a kinetic model of the nuclear replication–division cycle in frog eggs are estimated by fitting solutions of the kinetic equations (nonlinear ordinary differential equations) to a suite of experimental observations. A set of optimal parameter values is found by minimizing an obj ..."
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Cited by 5 (1 self)
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Parameter values for a kinetic model of the nuclear replication–division cycle in frog eggs are estimated by fitting solutions of the kinetic equations (nonlinear ordinary differential equations) to a suite of experimental observations. A set of optimal parameter values is found by minimizing an objective function defined as the orthogonal distance between the data and the model. The differential equations are solved by LSODAR and the objective function is minimized by ODRPACK. The optimal parameter values are close to the “guesstimates” of the modelers who first studied this problem. These tools are sufficiently general to attack more complicated problems, where guesstimation is impractical or unreliable. Key words: cyclindependent kinase, Mphase promoting factor, orthogonal distance regression, LevenbergMarquardt method. 1.
How and why more secure technologies succeed in legacy markets: Lessons from the success of SSH
 In Proceedings of the Second Annual Workshop on Economics and Information Security
, 2003
"... Secure shell (SSH) can safely be called one of the rare successes in which a more secure technology has largely replaced a less secure but entrenched tool: telnet. We perform a market analysis to determine how and why SSH succeeded despite the existence of an entrenched legacy tool while similar tec ..."
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Cited by 4 (0 self)
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Secure shell (SSH) can safely be called one of the rare successes in which a more secure technology has largely replaced a less secure but entrenched tool: telnet. We perform a market analysis to determine how and why SSH succeeded despite the existence of an entrenched legacy tool while similar technologies such as secure file transfer protocols have been far less successful. We show that network externalities, usually a first order effect, were not a significant factor impeding the adoption of SSH, and that SSH offered equivalent functionality and greater ease of use. We argue that these factors were the primary consideration in the willingness to change. Additionally, we argue that the openness of the standard, which facilitated the creation of numerous compatible implementations, was a key element in the economic decision made by system administrators.
An electron microscopic study of the morphology and distribution of the intracytoplasmic "viruslike" particles of Ehrlich ascites tumor cells
, 1957
"... During the course of a series of electron microscope studies on Ehrlich ascites tumor (EAT) cells, carried out in this laboratory, a distinctive particle was identified in close association with the endoplasmic reticulum of normal cells. Coincident with our findings this same observation was made by ..."
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Cited by 4 (0 self)
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During the course of a series of electron microscope studies on Ehrlich ascites tumor (EAT) cells, carried out in this laboratory, a distinctive particle was identified in close association with the endoplasmic reticulum of normal cells. Coincident with our findings this same observation was made by Caulfield