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Journal articles on the topic 'Temperature strings'

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Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

LIN, FENG-LI, TOSHIHIRO MATSUO, and DAN TOMINO. "HAGEDORN STRINGS IN AdS3." Modern Physics Letters A 23, no. 17n20 (June 28, 2008): 1552–64. http://dx.doi.org/10.1142/s0217732308027953.

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Motivated by the possibility of formulating a strings/black hole correspondence in AdS space, we extract the Hagedorn behavior of thermal AdS 3 bosonic string from 1-loop partition function of SL(2,R) WZW model. We find that the Hagedorn temperature is monotonically increasing as the AdS radius shrinks, reaches a maximum of order of string scale set by the unitarity bound of the CFT for internal space. The resulting density of states near the Hagedorn temperature resembles the form as for strings in flat space and is dominated by the space-like long string configurations. We also examine strings on BTZ background obtained through SL(2, Z) transformation. We find a tachyonic divergence for a BTZ black hole of string scale size.

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2

SATHIAPALAN, B. "THE HAGEDORN TRANSITION AND THE MATRIX MODEL FOR STRINGS." Modern Physics Letters A 13, no. 26 (August 30, 1998): 2085–94. http://dx.doi.org/10.1142/s0217732398002205.

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We use the matrix formalism to investigate what happens to strings above the Hagedorn temperature. We show that is not a limiting temperature but a temperature at which the continuum string picture breaks down. We study a collection of N D-0-branes arranged to form a string having N units of light-cone momentum. We find that at high temperatures the favored phase is one where the string worldsheet has disappeared and the low-energy degrees of freedom consists of N2 massless particles ("gluons"). The nature of the transition is very similar to the deconfinement transition in large-N Yang–Mills theories.

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3

Qin, Yanbin, Yinping Cao, Yihua Dou, Wenwen Lin, Jiahao Cao, and Luyao Wang. "Strength Failure of CO2 Injection Tubular Strings Considering CO2 Phase Transition." Energies 15, no. 23 (November 25, 2022): 8932. http://dx.doi.org/10.3390/en15238932.

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Compared with traditional injection tubular strings, the stresses on CO2 injection tubular strings are more complex. The results from field applications show that the phase transition of CO2 fluid in CO2 injection strings is an important factor in the calculation of temperature distribution and analysis of string mechanics. Therefore, we propose a strength analysis method for CO2 injection tubular strings that considers the CO2 phase transition. We selected four CO2 injection strings in an oil field in China as examples to evaluate their strength and safety. First, we established coupled differential equations for the temperature, pressure, and physical parameters of CO2 injection strings according to the theory of fluid flow and heat transfer. Then, we used an adaptive fuzzy neural network to construct the model for calculating the CO2 convection heat transfer coefficient and used this to obtain the high-precision convection heat transfer coefficients of tubular strings under conditions of CO2 flooding. We analyzed the injection-string deformations that resulted from the piston, spiral bending, expansion, friction and temperature effects according to the stress characteristics of the CO2 injection strings with packers under different working conditions. Finally, we performed mechanical analyses on the collapse resistance, internal pressure resistance, and tensile and triaxial stresses of the CO2 injection strings, and the results of these analyses provide a theoretical basis for the strength analysis of CO2 injection strings.

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4

CHAPLINE, G., and F. R. KLINKHAMER. "VORTICES IN HIGH-TEMPERATURE STRING THEORY." Modern Physics Letters A 04, no. 11 (June 10, 1989): 1063–67. http://dx.doi.org/10.1142/s0217732389001234.

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We discuss the role of XY-like vortices on the world-sheet for the free energy of strings at high temperatures. There is a Kosterlitz-Thouless phase transition at the Hagedorn temperature, above which the vortices contribute to the free energy in genus zero and generate a mass gap. We speculate that high-temperature “string” theory could be essentially discrete.

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5

Bowick, Mark J., and Steven B. Giddings. "High-temperature strings." Nuclear Physics B 325, no. 3 (October 1989): 631–46. http://dx.doi.org/10.1016/0550-3213(89)90500-2.

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6

Sanchez, N. G. "Advances in String Theory in Curved Backgrounds: A Synthesis Report." International Journal of Modern Physics A 18, no. 12 (May 10, 2003): 2011–22. http://dx.doi.org/10.1142/s0217751x0301543x.

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A synthetic report of the advances in the study of classical and quantum string dynamics in curved backgrounds is provided, namely : the new feature of Multistring solutions; the mass spectrum of Strings in Curved backgrounds; The effect of a Cosmological Constant and of Spacial Curvature on Classical and Quantum Strings; Classical splitting of Fundamental Strings; The General String Evolution in constant Curvature Spacetimes; The Conformal Invariance Effects; Strings on plane fronted and gravitational shock waves, string falling on spacetime singularities and its spectrum. New Developments in String Gravity and String Cosmology are reported: String driven cosmology and its Predictions; The primordial gravitational wave background; Non-singular string cosmologies from Exact Conformal Field Theories; Quantum Field Theory, String Temperature and the String Phase of de Sitter space-time; Hawking Radiation in String Theory and the String Phase of Black Holes; New Dual Relation between Quantum Field Theory regime and String regime and the "QFT/String Tango"; New Coherent String States and Minimal Uncertainty Principle in string theory.

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7

MATSUO, TOSHIHIRO. "HAGEDORN BEHAVIOR OF STRINGS IN AdS3/BTZ." International Journal of Modern Physics A 23, no. 14n15 (June 20, 2008): 2264–66. http://dx.doi.org/10.1142/s0217751x08041025.

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We study a finite temperature string in curved space, especially in AdS3 and BTZ black hole background. We extract Hagedorn behavior of strings and argue thermodynamic properties in thermal AdS3 as well as in BTZ black hole background. In particular, we find the Hagedorn temperature of string on AdS3, which depends on the AdS3 curvature scale. We also find a tachyonic divergence for a BTZ black hole of string scale.

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8

Arago, C., D. Bazeia, O. J. P. Éboli, and G. C. Marques. "Strings at finite temperature." Physical Review D 32, no. 12 (December 15, 1985): 3256–60. http://dx.doi.org/10.1103/physrevd.32.3256.

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9

Alvarez, E. "Strings at finite temperature." Nuclear Physics B 269, no. 3-4 (June 1986): 596–620. http://dx.doi.org/10.1016/0550-3213(86)90514-6.

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10

Odintsov, S. D., and I. M. Likhttsier. "Strings at nonzero temperature." Soviet Physics Journal 34, no. 12 (December 1991): 1053–89. http://dx.doi.org/10.1007/bf00896236.

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11

Salomonson, P., and B. S. Skagerstam. "Strings at finite temperature." Physica A: Statistical Mechanics and its Applications 158, no. 1 (May 1989): 499–515. http://dx.doi.org/10.1016/0378-4371(89)90545-1.

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12

NAGASAWA, MICHIYASU. "COSMOLOGICAL DEFECT AND HIGH ENERGY EXPERIMENTS." International Journal of Modern Physics A 22, no. 31 (December 20, 2007): 5785–99. http://dx.doi.org/10.1142/s0217751x07039018.

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The production and evolution of cosmological defects are investigated based on the standard particle physics theory such as the electroweak unified model and quantum chromodynamics. In these models, the string type solution can be obtained. Although electroweak strings and pion strings are embedded ones and topologically unstable, they would be stabilized by high temperature plasma and bring various cosmological consequences. Moreover, the production of pion strings may be observed in the LHC experiment.

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13

Liu, Wen Hong, Da Shun Qin, Zhi Yong Pan, Yan Long, and Kai Lin. "Study of Temperature Effect on the High Performance of OCTG Used for Deep and Ultra-Deep Well." Materials Science Forum 944 (January 2019): 797–807. http://dx.doi.org/10.4028/www.scientific.net/msf.944.797.

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With the exploitation of deep well, ultra-deep well, thermal recovery Well and Geothermal Well, the temperature of tubing and casing is increasing constantly. The influence degree of temperature on tubing and casing material performance has attracted much attention in the design of tubular strings. The experimental study on the yield strength and tensile strength of tubular materials with temperature change is carried out, which includes C110, 140ksi, P110 and S13Cr110. In this paper, the yield strength correction coefficient of tubular material is defined, and the material performance model of different steel grade tubular material with temperature change is established. The paper describes the influence of underground high temperature on the design of tubular strings and shows that the yield strength of tubular material will decrease under high temperature. This directly affects the safety parameter of tubing and casing design, and greatly impact on the safety reliability and service life of the tubular strings. This paper points out the defects which exist in the current API formulas, when calculating the force of the tubular string. It is suggested that the yield strength at high temperature should be used as the design basis for deep well and ultra-deep well when the underground temperature is high. The results can be used to guide the design and check of tubular strings under high temperature and high-pressure gas well.Keywords:deep and ultra-deep well; special performance tubing and casing; high temperature; yield strength; tubular strings integrity;OCTG

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14

Emond, William T., Sabir Ramazanov, and Rome Samanta. "Gravitational waves from melting cosmic strings." Journal of Cosmology and Astroparticle Physics 2022, no. 01 (January 1, 2022): 057. http://dx.doi.org/10.1088/1475-7516/2022/01/057.

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Abstract Appearance of cosmic strings in the early Universe is a common manifestation of new physics typically linked to some high energy scale. In this paper, we discuss a different situation, where a model underlying cosmic string formation is approximately scale free. String tension is naturally related to the square of the temperature of the hot primordial plasma in such a setting, and hence decreases with (cosmic) time. With gravitational backreaction neglected, the dynamics of these melting strings in an expanding Universe is equivalent to the dynamics of constant tension strings in a Minkowski spacetime. We provide an estimate for the emission of gravitational waves from string loops. Contrary to the standard case, the resulting spectrum is markedly non-flat and has a characteristic falloff at frequencies below the peak one. The peak frequency is defined by the underlying model and lies in the range accessible by the future detectors for very weak couplings involved.

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15

Salez, Thomas, Justin Salez, Kari Dalnoki-Veress, Elie Raphaël, and James A. Forrest. "Cooperative strings and glassy interfaces." Proceedings of the National Academy of Sciences 112, no. 27 (June 22, 2015): 8227–31. http://dx.doi.org/10.1073/pnas.1503133112.

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We introduce a minimal theory of glass formation based on the ideas of molecular crowding and resultant string-like cooperative rearrangement, and address the effects of free interfaces. In the bulk case, we obtain a scaling expression for the number of particles taking part in cooperative strings, and we recover the Adam–Gibbs description of glassy dynamics. Then, by including thermal dilatation, the Vogel–Fulcher–Tammann relation is derived. Moreover, the random and string-like characters of the cooperative rearrangement allow us to predict a temperature-dependent expression for the cooperative length ξ of bulk relaxation. Finally, we explore the influence of sample boundaries when the system size becomes comparable to ξ. The theory is in agreement with measurements of the glass-transition temperature of thin polymer films, and allows quantification of the temperature-dependent thickness hm of the interfacial mobile layer.

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16

BUND, S., and A. M. J. SCHAKEL. "STRING PICTURE OF BOSE–EINSTEIN CONDENSATION." Modern Physics Letters B 13, no. 11 (May 10, 1999): 349–62. http://dx.doi.org/10.1142/s0217984999000440.

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A nonrelativistic Bose gas is represented as a grand-canonical ensemble of fluctuating closed spacetime strings of arbitrary shape and length. The loops are characterized by their string tension and the number of times they wind around the imaginary time axis. At the temperature where Bose–Einstein condensation sets in, the string tension, being determined by the chemical potential, vanishes and the strings proliferate. A comparison with Feynman's description in terms of rings of cyclicly permuted bosons shows that the winding number of a loop corresponds to the number of particles contained in a ring.

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17

Diamantini, Maria Cristina, and Carlo Andrea Trugenberger. "Confining Strings at High Temperature." Journal of High Energy Physics 2002, no. 04 (April 17, 2002): 032. http://dx.doi.org/10.1088/1126-6708/2002/04/032.

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18

Giddings, Steven B. "Strings at the Hagedorn temperature." Physics Letters B 226, no. 1-2 (August 1989): 55–61. http://dx.doi.org/10.1016/0370-2693(89)90288-8.

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19

Derendinger, Jean-Pierre. "Temperature Instabilities inN = 4 Strings." Fortschritte der Physik 48, no. 1-3 (January 2000): 77–82. http://dx.doi.org/10.1002/(sici)1521-3978(20001)48:1/3<77::aid-prop77>3.0.co;2-u.

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20

LARSEN, A. L. "LOGARITHMIC CORRECTION TO SCALING FOR MULTISPIN STRINGS IN THE AdS5 BLACK HOLE BACKGROUND." International Journal of Modern Physics A 23, no. 05 (February 20, 2008): 719–27. http://dx.doi.org/10.1142/s0217751x08038482.

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We find new explicit solutions describing closed strings spinning with equal angular momentum in two independent planes in the AdS5 black hole space–time. These are 2n-folded strings in the radial direction and also winding m times around an angular direction. We specially consider these solutions in the long string and high temperature limit, where it is shown that there is a logarithmic correction to the scaling between energy and spin. This is similar to the one-spin case. The strings are spinning, or actually orbiting around the black hole of the AdS5 black hole space–time, similar to the solutions previously found in black hole space–times.

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21

Hills, Benjamin H., Joel T. Harper, Toby W. Meierbachtol, Jesse V. Johnson, Neil F. Humphrey, and Patrick J. Wright. "Processes influencing heat transfer in the near-surface ice of Greenland's ablation zone." Cryosphere 12, no. 10 (October 8, 2018): 3215–27. http://dx.doi.org/10.5194/tc-12-3215-2018.

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Abstract. To assess the influence of various heat transfer processes on the thermal structure of near-surface ice in Greenland's ablation zone, we compare in situ measurements with thermal modeling experiments. A total of seven temperature strings were installed at three different field sites, each with between 17 and 32 sensors and extending up to 21 m below the ice surface. In one string, temperatures were measured every 30 min, and the record is continuous for more than 3 years. We use these measured ice temperatures to constrain our modeling experiments, focusing on four isolated processes and assessing the relative importance of each for the near-surface ice temperature: (1) the moving boundary of an ablating surface, (2) thermal insulation by snow, (3) radiative energy input, and (4) subsurface ice temperature gradients below the seasonally active near-surface layer. In addition to these four processes, transient heating events were observed in two of the temperature strings. Despite no observations of meltwater pathways to the subsurface, these heating events are likely the refreezing of liquid water below 5–10 m of cold ice. Together with subsurface refreezing, the five heat transfer mechanisms presented here account for measured differences of up to 3 ∘C between the mean annual air temperature and the ice temperature at the depth where annual temperature variability is dissipated. Thus, in Greenland's ablation zone, the mean annual air temperature is not a reliable predictor of the near-surface ice temperature, as is commonly assumed.

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22

BYTSENKO, A. A., S. D. ODINTSOV, and S. ZERBINI. "HIGH TEMPERATURE EXPANSION OF STRING FREE ENERGY IN HYPERBOLIC SPACE." Modern Physics Letters A 10, no. 22 (July 20, 1995): 1619–26. http://dx.doi.org/10.1142/s0217732395001745.

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The high temperature behavior of the open bosonic string free energy in the space S1 ⊗ HN with vanishingly small curvature is investigated. The leading term of the high temperature expansion of the one-loop free energy, near the Hagedorn instability, is obtained. The problem of ir regularization of thermodynamical quantities is pointed out. For minimally coupling quantum fields related to the normal modes of strings, the results are similar to the ones valid for Rindler space. In the lower mass string states regime a connection with the quantum corrections to the black hole entropy is outlined.

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23

MUKOHYAMA, SHINJI. "D-BRANE CONFIGURATION AND BLACK HOLE THERMODYNAMICS." Modern Physics Letters A 11, no. 38 (December 14, 1996): 3035–40. http://dx.doi.org/10.1142/s0217732396003003.

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We consider a configuration of strings and solitons in the type IIB superstring theory on M5×T5, which is composed of a set of arbitrarily-wound D-five branes on T5 and a set of arbitrarily-wound D-strings on S1 of the torus. For the configuration, it is shown that number of microscopic states is bounded from above by the exponential of the Hawking-Bekenstein entropy of the corresponding black hole and the temperature of closed string radiation from the D-branes is bounded from below by the Hawking temperature of the black hole. After discussing the necessary and sufficient condition to saturate these bounds, we give some speculations about black hole thermodynamics.

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24

GERMÁN, G. "SOME DEVELOPMENTS IN POLYAKOV–KLEINERT STRING WITH EXTRINSIC CURVATURE STIFFNESS." Modern Physics Letters A 06, no. 20 (June 28, 1991): 1815–23. http://dx.doi.org/10.1142/s0217732391001962.

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We survey some developments in the theory of strings with extrinsic curvature stiffness proposed by Polyakov and Kleinert. Particular attention is devoted to work on the static quark potential, the string tension at finite temperature and the thermal deconfinement properties of the model.

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25

Alvarez, Enrique, and Tomas Ortin. "Critical temperature for interacting bosonic strings." Physics Letters B 241, no. 2 (May 1990): 215–17. http://dx.doi.org/10.1016/0370-2693(90)91281-f.

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26

Ringeval, Christophe. "Cosmic Strings and Their Induced Non-Gaussianities in the Cosmic Microwave Background." Advances in Astronomy 2010 (2010): 1–28. http://dx.doi.org/10.1155/2010/380507.

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Motivated by the fact that cosmological perturbations of inflationary quantum origin were born Gaussian, the search for non-Gaussianities in the cosmic microwave background (CMB) anisotropies is considered as the privileged probe of nonlinear physics in the early universe. Cosmic strings are active sources of gravitational perturbations and incessantly produce non-Gaussian distortions in the CMB. Even if, on the currently observed angular scales, they can only contribute a small fraction of the CMB angular power spectrum, cosmic strings could actually be the main source of its non-Gaussianities. In this paper, after having reviewed the basic cosmological properties of a string network, we present the signatures Nambu-Goto cosmic strings would induce in various observables ranging from the one-point function of the temperature anisotropies to the bispectrum and trispectrum. It is shown that string imprints are significantly different than those expected from the primordial type of non-Gaussianity and could therefore be easily distinguished.

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27

Singh, Dharm Veer, Md Sabir Ali, and Sushant G. Ghosh. "Noncommutative geometry inspired rotating black string." International Journal of Modern Physics D 27, no. 12 (September 2018): 1850108. http://dx.doi.org/10.1142/s0218271818501080.

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Noncommutativity is an idea dating back to that early times of quantum mechanics and the string theory induced noncommutative (NC) geometry provided an effective framework to study the short distance spacetime dynamics. Also, string theory, a candidate for a consistent quantum theory of gravity, admits a variety of classical black hole solutions including black strings. In this paper, we study a NC geometry inspired rotating black string to cylindrical spacetime with a source given by a smeared distribution of mass. The resulting metric is a regular everywhere, i.e. curvature-singularity free rotating black string, that in large [Formula: see text] limit interpolates Lemos black string. Thermodynamical properties of the black strings are also investigated and exact expressions for the temperature, the entropy and the heat capacity are obtained. Owing to the NC correction in the solution, the thermodynamic quantities have also been modified and that the NC geometry inspired black string is always thermodynamically stable.

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28

Lynch-Aird, Nicolas, and Jim Woodhouse. "Comparison of Mechanical Properties of Natural Gut and Synthetic Polymer Harp Strings." Materials 11, no. 11 (November 1, 2018): 2160. http://dx.doi.org/10.3390/ma11112160.

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The long-term mechanical behaviour of a number of fluorocarbon and gut harp strings has been examined, and the results compared with a previous study of rectified nylon strings. The stretching behaviour of the three materials was studied via different measures of the Young’s modulus; with test time scales on the order of weeks, minutes, and milliseconds. The strings were subjected to cyclic variations in temperature, enabling various aspects of their thermal behaviour to be investigated. The effects of humidity changes on gut strings were also examined. The behaviour of the fluorocarbon strings was found to be similar in many ways to that of the nylon strings, despite their different chemical formulation and significantly higher density. In particular, the faster measures of Young’s modulus were found to show an almost identical strong variation with the applied stress; while the thermal behaviour of both materials was largely determined by the balance between opposing effects associated with thermal contraction and thermal variations in the Young’s modulus. The gut strings showed some similarities of behaviour to the synthetic materials, but also major differences. All three measures of the Young’s modulus remained constant as the applied stress was increased. The gut strings were far more sensitive to changes in humidity than the synthetic materials, although some of the results, especially the thermal tuning sensitivity of the strings when held at constant length, displayed remarkable stability under changing humidity. The observed behaviour suggests very strongly that there is significant coupling between humidity-related changes in the linear density of a gut string and complementary changes in its tension.

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29

ELLIS, JOHN, NIKOLAOS E. MAVROMATOS, MICHAEL WESTMUCKETT, and DIMITRI V. NANOPOULOS. "LIOUVILLE COSMOLOGY AT ZERO AND FINITE TEMPERATURES." International Journal of Modern Physics A 21, no. 07 (March 20, 2006): 1379–444. http://dx.doi.org/10.1142/s0217751x06028990.

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We discuss cosmology in the context of Liouville strings, characterized by a central-charge deficit Q2, in which target time is identified with (the worldsheet zero mode of the) Liouville field: Q-Cosmology. We use a specific example of colliding braneworlds to illustrate the phase diagram of this cosmological framework. The collision provides the necessary initial cosmological instability, expressed as a departure from conformal invariance in the underlying string model. The brane motion provides a way of breaking target-space supersymmetry, and leads to various phases of the brane and bulk Universes. Specifically, we find a hot metastable phase for the bulk string Universe soon after the brane collision in which supersymmetry is broken, which we describe by means of a subcritical worldsheet σ-model dressed by a spacelike Liouville field, representing finite temperature (Euclidean time). This phase is followed by an inflationary phase for the brane Universe, in which the bulk string excitations are cold. This is described by a super-critical Liouville string with a timelike Liouville mode, whose zero mode is identified with the Minkowski target time. Finally, we speculate on possible ways of exiting the inflationary phase, either by means of subsequent collisions or by deceleration of the brane Universe due to closed-string radiation from the brane to the bulk. While phase transitions from hot to cold configurations occur in the bulk string universe, stringy excitations attached to the braneworld remain thermalized throughout, at a temperature which can be relatively high. The late-time behavior of the model results in dilaton-dominated dark energy and present-day acceleration of the expansion of the Universe, asymptoting eventually to zero.

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30

Jiang, Wen-Zhuang, Kuo-Ing Hwu, and Jenn-Jong Shieh. "LLC LED Driver with Current-Sharing Capacitor Having Low Voltage Stress." Energies 14, no. 1 (December 28, 2020): 112. http://dx.doi.org/10.3390/en14010112.

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In this paper, an LLC light-emitting diode (LLC LED) driver based on the current-sharing capacitor is presented. In the proposed LED driver, the LLC resonant converter is used to step down the high input voltage, to provide galvanic isolation, to offer a constant current for LEDs. Moreover, the current-sharing capacitor connected to the central-tapped point of the secondary-side winding is used to balance the currents in two LED strings. By doing so, the voltage stress on this capacitor is quite low. Above all, the equivalent forward voltages of the two LED strings are generally influenced by the temperature and the LED current, and this does not affect the current-sharing performance, as will be demonstrated by experiment on the difference in number of LEDs between the two LED strings. In addition, only the current in one LED string is sensed and controlled by negative feedback control, while the current in the other LED string is determined by the current-sharing capacitor. Moreover, this makes the current control so easy. Afterwards, the basic operating principles and analyses are given, particularly for how to derive the effective resistive load from the LED string. Eventually, some experimental results are provided to validate the effectiveness of the proposed LED driver.

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31

BOUCHAREB, A., M. RAMÓN MEDRANO, and N. G. SÁNCHEZ. "SEMICLASSICAL (QFT) AND QUANTUM (STRING) ROTATING BLACK HOLES AND THEIR EVAPORATION: NEW RESULTS." International Journal of Modern Physics A 22, no. 08n09 (April 10, 2007): 1627–48. http://dx.doi.org/10.1142/s0217751x07035252.

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Combination of both quantum field theory (QFT) and string theory in curved backgrounds in a consistent framework, the string analogue model, allows us to provide a full picture of the Kerr–Newman black hole and its evaporation going beyond the current picture. We compute the quantum emission cross-section of strings by a Kerr–Newman black hole (KNbh). It shows the black hole emission at the Hawking temperature T sem in the early stage of evaporation and the new string emission featuring a Hagedorn transition into a string state of temperature Ts at the last stages. New bounds on J and Q emerge in the quantum string regime (besides the known ones of the classical/semiclassical QFT regime). The last state of evaporation of a semiclassical Kerr–Newman black hole with mass M > m Pl , angular momentum J and charge Q is a string state of temperature Ts, string mass Ms, J = 0 and Q = 0, decaying as usual quantum strings do into all kinds of particles. (Naturally, in this framework, there is no loss of information, (there is no paradox at all).) We compute the string entropy Ss(m, j) from the microscopic string density of states of mass m and spin mode j, ρ(m, j). (Besides the Hagedorn transition at Ts) we find for high j (extremal string states j → m2α′c), a new phase transition at a temperature [Formula: see text], higher than Ts. By precisely identifying the semiclassical and quantum (string) gravity regimes, we find a new formula for the Kerr black hole entropy S sem (M, J), as a function of the usual Bekenstein–Hawking entropy [Formula: see text]. For M ≫ m Pl and J < GM2/c, [Formula: see text] is the leading term, but for high angular momentum, (nearly extremal case J = GM2/c), a gravitational phase transition operates and the whole entropy S sem is drastically different from the Bekenstein–Hawking entropy [Formula: see text]. This new extremal black hole transition occurs at a temperature T sem J = (J/ℏ)T sem , higher than the Hawking temperature T sem .

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32

NEUBAUER, D., K. SAILER, B. MÜLLER, H. STÖCKER, and W. GREINER. "SURVIVAL OF J/Ψ IN HADRONIC MATTER AT HIGH ENERGY DENSITY?" Modern Physics Letters A 04, no. 17 (September 10, 1989): 1627–34. http://dx.doi.org/10.1142/s0217732389001854.

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The collision rate of massive strings representing J/Ψ mesons has been determined by numerical simulation, modelling the surrounding hadronic matter as an ideal string gas in thermodynamical equilibrium. The survival time of the J/Ψ string tends to zero at the Hagedorn temperature. Whether the final state J/Ψ-nucleon scattering accounts for a major part of the observed J/Ψ suppression, depends on the value of the J/Ψ-nucleon cross section.

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33

Germán, G., and H. Kleinert. "Two-loop string tension of stiff strings at finite temperature in any dimension." Physics Letters B 220, no. 1-2 (March 1989): 133–36. http://dx.doi.org/10.1016/0370-2693(89)90025-7.

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34

OSORIO, M. A. R. "QUANTUM FIELDS VERSUS STRINGS AT FINITE TEMPERATURE." International Journal of Modern Physics A 07, no. 18 (July 20, 1992): 4275–92. http://dx.doi.org/10.1142/s0217751x92001903.

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We study some aspects of the relationship between the one-loop free energy of closed superstrings computed as a sum over the free energies of the quantum fields present in the string (the analog model) and the modular invariant expression of the same quantity. In particular, by getting a generalized duality relation for the integrand of the modular invariant expression for the free energy of closed superstrings and using a regularization procedure, we connect the contribution to the vacuum energy from the bosonic degrees of freedom in the analog model (one half of the total number) with the coefficient governing the high temperature behavior of the free energy. We also study the physical meaning of this regularization and the role played by the left-right constraint defining the physical fields in the light-cone gauge.

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35

Sfetsos, Konstadinos. "Supersymmetric phases of finite-temperature strings II." Journal of High Energy Physics 2000, no. 11 (November 2, 2000): 005. http://dx.doi.org/10.1088/1126-6708/2000/11/005.

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36

Lee, Sangmin, and Lárus Thorlacius. "Strings and D-branes at high temperature." Physics Letters B 413, no. 3-4 (November 1997): 303–10. http://dx.doi.org/10.1016/s0370-2693(97)01105-2.

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37

Ahmed, E. "Temperature and the critical dimension of strings." International Journal of Theoretical Physics 26, no. 12 (December 1987): 1135–40. http://dx.doi.org/10.1007/bf00671337.

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38

Gopalakrishnan, Sarang, Romain Vasseur, and Brayden Ware. "Anomalous relaxation and the high-temperature structure factor of XXZ spin chains." Proceedings of the National Academy of Sciences 116, no. 33 (July 30, 2019): 16250–55. http://dx.doi.org/10.1073/pnas.1906914116.

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We compute the spin-structure factor of XXZ spin chains in the Heisenberg and gapped (Ising) regimes in the high-temperature limit for nonzero magnetization, within the framework of generalized hydrodynamics, including diffusive corrections. The structure factor shows a hierarchy of timescales in the gapped phase, owing to s-spin magnon bound states (“strings”) of various sizes. Although short strings move ballistically, long strings move primarily diffusively as a result of their collisions with short strings. The interplay between these effects gives rise to anomalous power-law decay of the spin-structure factor, with continuously varying exponents, at any fixed separation in the late-time limit. We elucidate the cross-over to diffusion (in the gapped phase) and to superdiffusion (at the isotropic point) in the half-filling limit. We verify our results via extensive matrix product operator calculations.

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39

Li, Guoli, Fei Feng, Fang Wang, and Bo Wei. "Temperature Field Measurement of Photovoltaic Module Based on Fiber Bragg Grating Sensor Array." Materials 15, no. 15 (August 2, 2022): 5324. http://dx.doi.org/10.3390/ma15155324.

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Studying the temperature field of photovoltaic modules is important for improving their power generation efficiency. To solve the problem of traditional sensors being unsuitable for measuring the spatial temperature field, we designed a real-time detection scheme of the photovoltaic module temperature field based on a fiber Bragg grating (FBG) sensor array. In this scheme, wavelength division multiplexing and space division multiplexing technologies were applied. The multi-channel FBG sensor strings were arranged on the surface and in the near field of the photovoltaic module. Different FBG strings were selected through optical switches, and the wavelength of the FBG string was addressed and demodulated using the tunable laser method and a peak-seeking algorithm. A measurement experiment of the photovoltaic module temperature field was carried out in an outdoor environment. The experimental results showed that the fluctuation law of the photovoltaic module surface and near-field temperature is basically consistent with that of solar radiation power. The temperature of the photovoltaic module decayed from the surface to space. Within 6 mm of the photovoltaic module surface, the temperature sharply dropped, and then the downward trend became flat. The lower the solar radiation power and the higher the wind speed, the faster the temperature decay. This method provides technical support for measuring the temperature field of a photovoltaic module and other heat source equipment.

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40

CIRILO-LOMBARDO, D. J., and N. G. SANCHEZ. "MICROCANONICAL MODEL FOR A GAS OF EVAPORATING BLACK HOLES AND STRINGS, SCATTERING AMPLITUDES AND MASS SPECTRUM." International Journal of Modern Physics A 23, no. 07 (March 20, 2008): 975–1000. http://dx.doi.org/10.1142/s0217751x08039554.

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We study the system formed by a gas of black holes and strings within a microcanonical formulation. The density of mass levels grows asymptotically as [Formula: see text], (i = 1,…,N). We derive the microcanonical content of the system: entropy, equation of state, number of components N, temperature T and specific heat. The pressure and the specific heat are negative reflecting the gravitational unstability and a nonhomogeneous configuration. The asymptotic behavior of the temperature for large masses emerges as the Hawking temperature of the system (classical or semiclassical phase) in which the classical black hole behavior dominates, while for small masses (quantum black hole or string behavior) the temperature becomes the string temperature which emerges as the critical temperature of the system. At low masses, a phase transition takes place showing the passage from the classical (black hole) to quantum (string) behavior. Within a microcanonical field theory formulation, the propagator describing the string–particle–black hole system is derived and from it the interacting four-point scattering amplitude of the system is obtained. For high masses it behaves asymptotically as the degeneracy of states ρ(m) of the system (i.e. duality or crossing symmetry). The microcanonical propagator and partition function are derived from a (Nambu–Goto) formulation of the N-extended objects and the mass spectrum of the black hole–string system is obtained: for small masses (quantum behavior) these yield the usual pure string scattering amplitude and string–particle spectrum [Formula: see text]; for growing mass the spectrum describes all the intermediate states up to the pure black hole behavior. The different black hole behaviors according to the different mass ranges: classical, semiclassical and quantum or string behaviors are present in the model.

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41

MONIN, A., and M. B. VOLOSHIN. "EFFECTS OF EXTRA DEGREES OF FREEDOM ON A DECAY RATE OF METASTABLE TOPOLOGICAL OBJECTS." International Journal of Modern Physics A 25, no. 02n03 (January 30, 2010): 300–309. http://dx.doi.org/10.1142/s0217751x10048627.

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We review the recent results on a decay rate of metastable topological configurations such as strings and domain walls. The transition from a state with higher tension to a state with lower one proceeds through quantum tunneling or through thermally catalyzed quantum tunneling (at sufficiently small temperatures). It is shown that the effects of the motion in transverse direction lead to the renormalization of a mass (tension) parameter of a particle (string) associated with a boundary of a string (wall) in the semiclassical exponent. For a non-zero temperature we derive the catalysis factor for the decay rates. It is discovered that the catalysis factor is closely related to the probability (effective length) of the collision of the the Goldstone bosons, corresponding to the transverse waves on a string (wall). We find that the destruction of a string only takes place in collisions of even number of the bosons, while the destruction of the wall can occur in a collision of any number of particles.

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42

Pourbabak, Saeid, Xiebin Wang, Dirk Van Dyck, Bert Verlinden, and Dominique Schryvers. "Ni cluster formation in low temperature annealed Ni50.6Ti49.4." Functional Materials Letters 10, no. 01 (February 2017): 1740005. http://dx.doi.org/10.1142/s1793604717400057.

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Various low temperature treatments of Ni[Formula: see text]Ti[Formula: see text] have shown an unexpected effect on the martensitic start temperature. Periodic diffuse intensity distributions in reciprocal space indicate the formation of short pure Ni strings along the [Formula: see text]111[Formula: see text] directions in the B2 ordered lattice, precursing the formation of Ni4Ti3 precipitates formed at higher annealing temperatures.

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43

S Bakry, A., X. Chen, M. Deliyergiyev, A. Galal, A. Khalaf, and P. M Pengming. "Stiff self-interacting strings at high temperature QCD." EPJ Web of Conferences 175 (2018): 12004. http://dx.doi.org/10.1051/epjconf/201817512004.

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We investigate the implications of Nambu-Goto (NG), Lüscher Weisz (LW) and Polyakov-Kleinert (PK) effective string actions for the Casimir energy and the width of the quantum delocalization of the string in 4-dim pure SU(3) Yang-Mills lattice gauge theory. At a temperature closer to the critical point T/Tc=0.9, we found that the next to leading-order (NLO) contributions from the expansion of the NG string in addition to the boundary terms in LW action to decrease the deviations from the lattice data in the intermediate distance scales for both the quark-antiquark QQ̅ potential and broadening of the color tube compared to the free string approximation. We conjecture possible stiffness of the QCD string through studying the effects of extrinsic curvature term in PK action and find a good fitting behavior for the lattice Monte-Carlo data at both long and intermediate quark separations regions.

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44

Kar, Supriya, and Sudhakar Panda. "Electro-magnetic Strings: Complementarity between Time and Temperature." Journal of High Energy Physics 2002, no. 11 (November 28, 2002): 052. http://dx.doi.org/10.1088/1126-6708/2002/11/052.

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Chen, Jian, and Wayne A. Weimer. "Room-Temperature Assembly of Directional Carbon Nanotube Strings." Journal of the American Chemical Society 124, no. 5 (February 2002): 758–59. http://dx.doi.org/10.1021/ja017384t.

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46

Antoniadis, I., J. P. Derendinger, and C. Kounnas. "Non-perturbative temperature instabilities in N = 4 strings." Nuclear Physics B 551, no. 1-2 (June 1999): 41–77. http://dx.doi.org/10.1016/s0550-3213(99)00171-6.

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47

Deo, Nivedita, Sanjay Jain, and Chung-I. Tan. "Strings at high energy densities and complex temperature." Physics Letters B 220, no. 1-2 (March 1989): 125–32. http://dx.doi.org/10.1016/0370-2693(89)90024-5.

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48

Shiraishi, K. "Can Virtual Cosmic Strings Shift the Hawking Temperature?" Europhysics Letters (EPL) 20, no. 6 (November 15, 1992): 483–85. http://dx.doi.org/10.1209/0295-5075/20/6/002.

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49

Roy, P., B. Roy, and R. Roychoudhury. "On the localisation of strings at finite temperature." Classical and Quantum Gravity 5, no. 10 (October 1, 1988): 1393–96. http://dx.doi.org/10.1088/0264-9381/5/10/018.

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50

Dotsenko, Victor. "One dimensional directed polymer ‘memory model’." Journal of Statistical Mechanics: Theory and Experiment 2022, no. 9 (September 1, 2022): 093302. http://dx.doi.org/10.1088/1742-5468/ac8c96.

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Abstract In this paper, I propose a very simple statistical ‘memory model’ of one-dimensional directed polymers, which is capable of storing and retrieving a given random quenched trajectory. The model is defined in terms of the elastic string Hamiltonian with the local attractive potential between the dynamic and the quenched random strings. The average overlap between them is calculated as a function of the temperature and the strength of the attractive potential.

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