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Journal articles on the topic 'Conformal predictions'

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Published: 4 June 2021

Last updated: 5 February 2022

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Balasubramanian, Vineeth N., Shayok Chakraborty, and Sethuraman Panchanathan. "Conformal predictions for information fusion." Annals of Mathematics and Artificial Intelligence 74, no. 1-2 (2014): 45–65. http://dx.doi.org/10.1007/s10472-013-9392-4.

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Wang, You, Zhan Wang, Junwei Diao, Xiyang Sun, Zhiyuan Luo, and Guang Li. "Discrimination of Different Species of Dendrobium with an Electronic Nose Using Aggregated Conformal Predictor." Sensors 19, no. 4 (2019): 964. http://dx.doi.org/10.3390/s19040964.

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A method using electronic nose to discriminate 10 different species of dendrobium, which is a kind of precious herb with medicinal application, was developed with high efficiency and low cost. A framework named aggregated conformal prediction was applied to make predictions with accuracy and reliability for E-nose detection. This method achieved a classification accuracy close to 80% with an average improvement of 6.2% when compared with the results obtained by using traditional inductive conformal prediction. It also provided reliability assessment to show more comprehensive information for each prediction. Meanwhile, two main indicators of conformal predictor, validity and efficiency, were also compared and discussed in this work. The result shows that the approach integrating electronic nose with aggregated conformal prediction to classify the species of dendrobium with reliability and validity is promising.

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Balasubramanian, Vineeth N. "Conformal predictions in multimedia pattern recognition." ACM SIGMultimedia Records 3, no. 1 (2011): 23–24. http://dx.doi.org/10.1145/2069196.2069202.

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Papadopoulos, H., V. Vovk, and A. Gammerman. "Regression Conformal Prediction with Nearest Neighbours." Journal of Artificial Intelligence Research 40 (April 30, 2011): 815–40. http://dx.doi.org/10.1613/jair.3198.

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In this paper we apply Conformal Prediction (CP) to the k-Nearest Neighbours Regression (k-NNR) algorithm and propose ways of extending the typical nonconformity measure used for regression so far. Unlike traditional regression methods which produce point predictions, Conformal Predictors output predictive regions that satisfy a given confidence level. The regions produced by any Conformal Predictor are automatically valid, however their tightness and therefore usefulness depends on the nonconformity measure used by each CP. In effect a nonconformity measure evaluates how strange a given example is compared to a set of other examples based on some traditional machine learning algorithm. We define six novel nonconformity measures based on the k-Nearest Neighbours Regression algorithm and develop the corresponding CPs following both the original (transductive) and the inductive CP approaches. A comparison of the predictive regions produced by our measures with those of the typical regression measure suggests that a major improvement in terms of predictive region tightness is achieved by the new measures.

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Al-Jamel, Ahmed. "Heavy quarkonia properties from a hard-wall confinement potential model with conformal symmetry perturbing effects." Modern Physics Letters A 34, no. 37 (2019): 1950307. http://dx.doi.org/10.1142/s0217732319503073.

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Heavy [Formula: see text] and [Formula: see text] quarkonia are considered as systems confined within a hard-wall potential shaped after a linear combination of a cotangent — with a square co-secant function. Wave functions and energy spectra are then obtained in closed forms in solving by the Nikiforov–Uvarov method the associated radial Schrödinger equation in the presence of a centrifugal term. The interest in this potential is that in one parametrization, it can account for a conformal symmetry of the strong interaction, and in another for its perturbation, a reason for which we here employ it to study status of conformal symmetry in the heavy flavor sector. The resulting predictions on heavy quarkonia mass spectra and root mean square radii are compared with the available experimental data, as well as with predictions by other theoretical approaches. We observe that a relatively small conformal symmetry perturbing term in the potential suffices to achieve good agreement with data.

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WYDRO, TOMASZ, and JOHN F. McCABE. "CONFORMAL THEORY FOR YANG–LEE SINGULARITY OF 2D 3-STATE POTTS MODEL." International Journal of Modern Physics B 19, no. 18 (2005): 3021–35. http://dx.doi.org/10.1142/s0217979205030839.

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We identify a conformal field theory (CFT) that describes the Yang–Lee edge singularity of the 2-dimensional (2D) 3-state Potts model. The identification is based on a comparison of finite-size scaling measurements to predictions for conformal minimal models. The comparison shows that the Yang–Lee edge singularities of the 2D 3-state Potts and the 2D Ising models are in the same universality class.

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LAMBROU, ANTONIS, HARRIS PAPADOPOULOS, EFTHYVOULOS KYRIACOU, et al. "EVALUATION OF THE RISK OF STROKE WITH CONFIDENCE PREDICTIONS BASED ON ULTRASOUND CAROTID IMAGE ANALYSIS." International Journal on Artificial Intelligence Tools 21, no. 04 (2012): 1240016. http://dx.doi.org/10.1142/s0218213012400167.

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Conformal Predictors (CPs) are Machine Learning algorithms that can provide reliable confidence measures to their predictions. In this work, we make use of the Conformal Prediction framework for the assessment of stroke risk based on ultrasound images of atherosclerotic carotid plaques. For this application, images were recorded from 137 asymptomatic and 137 symptomatic plaques (symptoms are Stroke, Transient Ischaemic Attack (TIA), and Amaurosis Fugax (AF)). Two feature sets were extracted from the plaques; the first based on morphological image analysis and the second based on image texture analysis. Both sets were used in order to evaluate the performance of CPs on this problem. Four CPs were constructed using four popular classification methods, namely Artificial Neural Networks (ANNs), Support Vector Machines (SVMs), Naive Bayes Classification (NBC), and k -Nearest Neighbours. The results given by all CPs demonstrate the reliability and importance of the obtained confidence measures on the problem of stroke risk assessment.

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HENKEL, MALTE. "AGEING, DYNAMICAL SCALING AND CONFORMAL INVARIANCE." International Journal of Modern Physics A 19, no. 14 (2004): 2207–15. http://dx.doi.org/10.1142/s0217751x04018440.

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Building on an analogy with conformal invariance, local scale transformations consistent with dynamical scaling are constructed. Two types of local scale invariance are found which act as dynamical space–time symmetries of certain nonlocal free field theories. The scaling form of two-point functions is completely fixed by the requirement of local scale invariance. These predictions are confirmed through tests in the 3D ANNNI model at its Lifshitz point and in ageing phenomena of simple ferromagnets, here studied through the kinetic Ising model with Glauber dynamics.

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Leib, S. J. "Noise Predictions for Rectangular Jets Using a Conformal Mapping Method." AIAA Journal 51, no. 3 (2013): 721–37. http://dx.doi.org/10.2514/1.j052190.

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Belitsky, A. V., and D. Müller. "Predictions from conformal algebra for the deeply virtual Compton scattering." Physics Letters B 417, no. 1-2 (1998): 129–40. http://dx.doi.org/10.1016/s0370-2693(97)01390-7.

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Harismiadis, V. I., N. K. Koutras, D. P. Tassios, and A. Z. Panagiotopoulos. "How good is conformal solutions theory for phase equilibrium predictions?" Fluid Phase Equilibria 65 (January 1991): 1–18. http://dx.doi.org/10.1016/0378-3812(91)87014-z.

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Kennedy, Tom. "Conformal Invariance Predictions for the Three-Dimensional Self-Avoiding Walk." Journal of Statistical Physics 158, no. 6 (2014): 1195–212. http://dx.doi.org/10.1007/s10955-014-1183-8.

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KRIZ, IGOR. "PERTURBATIVE DEFORMATIONS OF CONFORMAL FIELD THEORIES REVISITED." Reviews in Mathematical Physics 22, no. 02 (2010): 117–92. http://dx.doi.org/10.1142/s0129055x10003916.

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The purpose of this paper is to revisit the theory of perturbative deformations of conformal field theory from a mathematically rigorous, purely worldsheet point of view. We specifically include the case of N = (2,2) conformal field theories. From this point of view, we find certain surprising obstructions, which appear to indicate that contrary to previous findings, not all deformations along marginal fields exist perturbatively. This includes the case of deformation of the Gepner model of the Fermat quintic along certain cc fields. In other cases, including Gepner models of K3-surfaces and the free field theory, our results coincides with known predictions. We give partial interpretation of our results via renormalization and mirror symmetry.

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Brodsky, Stanley. "Supersymmetric and Conformal Features of Hadron Physics." Universe 4, no. 11 (2018): 120. http://dx.doi.org/10.3390/universe4110120.

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The QCD Lagrangian is based on quark and gluonic fields—not squarks nor gluinos. However, one can show that its hadronic eigensolutions conform to a representation of superconformal algebra, reflecting the underlying conformal symmetry of chiral QCD. The eigensolutions of superconformal algebra provide a unified Regge spectroscopy of meson, baryon, and tetraquarks of the same parity and twist as equal-mass members of the same 4-plet representation with a universal Regge slope. The predictions from light-front holography and superconformal algebra can also be extended to mesons, baryons, and tetraquarks with strange, charm and bottom quarks. The pion q q ¯ eigenstate has zero mass for m q = 0 . A key tool is the remarkable observation of de Alfaro, Fubini, and Furlan (dAFF) which shows how a mass scale can appear in the Hamiltonian and the equations of motion while retaining the conformal symmetry of the action. When one applies the dAFF procedure to chiral QCD, a mass scale κ appears which determines universal Regge slopes, hadron masses in the absence of the Higgs coupling. One also predicts the form of the nonperturbative QCD running coupling: α s ( Q 2 ) ∝ e - Q 2 / 4 κ 2 , in agreement with the effective charge determined from measurements of the Bjorken sum rule. One also obtains viable predictions for spacelike and timelike hadronic form factors, structure functions, distribution amplitudes, and transverse momentum distributions. The combination of conformal symmetry, light-front dynamics, its holographic mapping to AdS 5 space, and the dAFF procedure thus provide new insights, not only into the physics underlying color confinement, but also the nonperturbative QCD coupling and the QCD mass scale.

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Hasenfratz, Anna, Claudio Rebbi, and Oliver Witzel. "Testing Fermion Universality at a Conformal Fixed Point." EPJ Web of Conferences 175 (2018): 03006. http://dx.doi.org/10.1051/epjconf/201817503006.

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Universality of various fermion formulations is well established in QCD-like theories defined around the perturbative g2 = 0 fixed point. These arguments do not apply for conformal systems that exhibit an infrared fixed point at non-vanishing g2 coupling. We investigate the step scaling function for systems with 10 or 12 fundamental flavors using domain wall fermions and compare it to perturbative predictions. We test universality by contrasting our findings to results published in the literature based on staggered fermions.

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Ren, Yitong, Zhaojun Gu, Zhi Wang, et al. "System Log Detection Model Based on Conformal Prediction." Electronics 9, no. 2 (2020): 232. http://dx.doi.org/10.3390/electronics9020232.

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With the rapid development of the Internet of Things, the combination of the Internet of Things with machine learning, Hadoop and other fields are current development trends. Hadoop Distributed File System (HDFS) is one of the core components of Hadoop, which is used to process files that are divided into data blocks distributed in the cluster. Once the distributed log data are abnormal, it will cause serious losses. When using machine learning algorithms for system log anomaly detection, the output of threshold-based classification models are only normal or abnormal simple predictions. This paper used the statistical learning method of conformity measure to calculate the similarity between test data and past experience. Compared with detection methods based on static threshold, the statistical learning method of the conformity measure can dynamically adapt to the changing log data. By adjusting the maximum fault tolerance, a system administrator can better manage and monitor the system logs. In addition, the computational efficiency of the statistical learning method for conformity measurement was improved. This paper implemented an intranet anomaly detection model based on log analysis, and conducted trial detection on HDFS data sets quickly and efficiently.

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MCCABE, JOHN F., and TOMASZ WYDRO. "EXCITATION SPECTRUM AT THE YANG–LEE EDGE SINGULARITY OF THE 2D ISING MODEL." International Journal of Modern Physics B 20, no. 04 (2006): 495–504. http://dx.doi.org/10.1142/s021797920603336x.

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This paper studies the Yang–Lee edge singularity of 2-dimensional (2D) Ising model through a quantum spin chain. In particular, finite-size scaling measurements on the quantum spin chain are used to determine the low-lying excitation spectrum and central charge at the Yang–Lee edge singularity. The measured values are consistent with predictions for the (A4, A1) minimal conformal field theory.

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Saha, Debasish, Amarjit Tamang, Ramil Izmailov, Carlo Cattani, and Kamal K. Nandi. "First-Order Light Deflection by Einstein-Strauss Vacuole Method." Journal of Gravity 2013 (August 1, 2013): 1–4. http://dx.doi.org/10.1155/2013/686950.

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We resolve here an outstanding problem plaguing conformal gravity in its role in making consistent astrophysical predictions. Though its static spherically symmetric solution incorporates all the successes of Schwarzschild gravity, the fit to observed galactic rotation curves requires γ>0, while the observed increase in the Schwarzschild light deflection by galaxies appears to demand γ<0. Here we show that, contrary to common knowledge, there is an increase in the Schwarzschild deflection angle in the vicinity of galaxies due purely to the effect of γ>0, when the idea of the Einstein-Strauss vacuole model is employed. With the inconsistency now out of the way, conformal gravity should be regarded as a good theory explaining light deflection by galaxies.

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MENA MARUGÁN, GUILLERMO A. "REALITY CONDITIONS FOR LORENTZIAN AND EUCLIDEAN GRAVITY IN THE ASHTEKAR FORMULATION." International Journal of Modern Physics D 03, no. 03 (1994): 513–28. http://dx.doi.org/10.1142/s0218271894000678.

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Using Ashtekar variables, we analyze Lorentzian and Euclidean gravity in vacuum up to a constant conformal transformation. Keeping unaltered the symplectic structure in the full theory of complex gravity, we prove that the reality conditions are invariant under a Wick rotation of the time, and show that the compatibility of the algebra of commutators and constraints with the involution defined by the reality conditions restricts the possible values of the conformal factor to be either real or purely imaginary. In the first case, one recovers real Lorentzian general relativity. For purely imaginary conformal factors, the classical theory can be interpreted as real Euclidean gravity. The reality conditions associated with this Euclidean theory demand the hermiticity of the Ashtekar connection, but the densitized triad is represented by an anti-Hermitian operator. We also demonstrate that the Euclidean and Lorentzian sets of reality conditions lead to inequivalent quantizations of full general relativity. This conclusion also holds in the geometrodynamic formulation. As a consequence, it seems impossible to obtain Lorentzian physical predictions from the quantum theory constructed with the Euclidean reality conditions.

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Caracciolo, S., A. Pelissetto, and A. D. Sokal. "Universal distance ratios for two-dimensonal self-avoiding walks: corrected conformal-invariance predictions." Journal of Physics A: Mathematical and General 23, no. 18 (1990): L969—L974. http://dx.doi.org/10.1088/0305-4470/23/18/006.

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Barkema, G. T., and John McCabe. "Monte Carlo simulations of conformal theory predictions for the three-state Potts model." Journal of Statistical Physics 84, no. 5-6 (1996): 1067–75. http://dx.doi.org/10.1007/bf02174128.

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Yazdani, Nuri, Vipin Chawla, Eve Edwards, Vanessa Wood, Hyung Gyu Park, and Ivo Utke. "Modeling and optimization of atomic layer deposition processes on vertically aligned carbon nanotubes." Beilstein Journal of Nanotechnology 5 (March 5, 2014): 234–44. http://dx.doi.org/10.3762/bjnano.5.25.

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Many energy conversion and storage devices exploit structured ceramics with large interfacial surface areas. Vertically aligned carbon nanotube (VACNT) arrays have emerged as possible scaffolds to support large surface area ceramic layers. However, obtaining conformal and uniform coatings of ceramics on structures with high aspect ratio morphologies is non-trivial, even with atomic layer deposition (ALD). Here we implement a diffusion model to investigate the effect of the ALD parameters on coating kinetics and use it to develop a guideline for achieving conformal and uniform thickness coatings throughout the depth of ultra-high aspect ratio structures. We validate the model predictions with experimental data from ALD coatings of VACNT arrays. However, the approach can be applied to predict film conformality as a function of depth for any porous topology, including nanopores and nanowire arrays.

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Hammer, Hans-Werner, and Dam Thanh Son. "Unnuclear physics: Conformal symmetry in nuclear reactions." Proceedings of the National Academy of Sciences 118, no. 35 (2021): e2108716118. http://dx.doi.org/10.1073/pnas.2108716118.

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We investigate a nonrelativistic version of Georgi’s “unparticle physics.” We define the unnucleus as a field in a nonrelativistic conformal field theory. Such a field is characterized by a mass and a conformal dimension. We then consider the formal problem of scatterings to a final state consisting of a particle and an unnucleus and show that the differential cross-section, as a function of the recoil energy received by the particle, has a power-law singularity near the maximal recoil energy, where the power is determined by the conformal dimension of the unnucleus. We argue that unlike the relativistic unparticle, which remains a hypothetical object, the unnucleus is realized, to a good approximation, in nuclear reactions involving emission of a few neutrons, when the energy of the final-state neutrons in their center-of-mass frame lies in the range between about 0.1 MeV and 5 MeV. Combining this observation with the known universal properties of fermions at unitarity in a harmonic trap, we predict a power-law behavior of an inclusive cross-section in this kinematic regime. We verify our predictions with previous effective field theory and model calculations of the 6He(p,pα)2n, 3H(π−,γ)3n, and 3H(μ−,νμ)3n reactions and discuss opportunities to measure unnuclei at radioactive beam facilities.

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Kattan, Michael W., Michael J. Zelefsky, Patrick A. Kupelian, Peter T. Scardino, Zvi Fuks, and Steven A. Leibel. "Pretreatment Nomogram for Predicting the Outcome of Three-Dimensional Conformal Radiotherapy in Prostate Cancer." Journal of Clinical Oncology 18, no. 19 (2000): 3352–59. http://dx.doi.org/10.1200/jco.2000.18.19.3352.

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PURPOSE: Several studies have defined risk groups for predicting the outcome after external-beam radiotherapy of localized prostate cancer. However, most models formed patient risk groups, and none of these models considers radiation dose as a predictor variable. The purpose of this study was to develop a nomogram to improve the accuracy of predicting outcome after three-dimensional conformal radiotherapy. MATERIALS AND METHODS: This study was a retrospective, nonrandomized analysis of patients treated at the Memorial Sloan-Kettering Cancer Center between 1988 and 1998. Clinical parameters of the 1,042 patients included stage, biopsy Gleason score, pretreatment serum prostate-specific antigen (PSA) level, whether neoadjuvant androgen deprivation therapy was administered, and the radiation dose delivered. Biochemical (PSA) treatment failure was scored when three consecutive rises of serum PSA occurred. A nomogram, which predicts the probability of remaining free from biochemical recurrence for 5 years, was validated internally on this data set using a bootstrapping method and externally using a cohort of patients treated at the Cleveland Clinic, Cleveland, OH. RESULTS: When predicting outcomes for patients in the validation data set from the Cleveland Clinic, the nomogram had a Somers’ D rank correlation between predicted and observed failure times of 0.52. Predictions from this nomogram were more accurate (P < .0001) than the best of seven published risk stratification systems, which achieved a Somers’ D coefficient of 0.47. CONCLUSION: The development process illustrated here produced a nomogram that seems to predict more accurately than other available systems and may be useful for treatment selection by both physicians and patients.

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FORKEL, HILMAR, MICHAEL BEYER, and TOBIAS FREDERICO. "LINEAR MESON AND BARYON TRAJECTORIES IN ADS/QCD." International Journal of Modern Physics E 16, no. 09 (2007): 2794–97. http://dx.doi.org/10.1142/s0218301307008422.

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An approximate holographic dual of QCD is constructed and shown to reproduce the empirical linear trajectories of universal slope on which the square masses of radially and orbitally excited hadrons join. Conformal symmetry breaking and other IR effects are described exclusively by deformations of the anti-de Sitter background metric. The predictions for the light hadron spectrum include new relations between ground state masses and trajectory slopes and are in good overall agreement with experimental data.

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McCullagh, Peter, and David Clifford. "Evidence for conformal invariance of crop yields." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 462, no. 2071 (2006): 2119–43. http://dx.doi.org/10.1098/rspa.2006.1667.

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The aim of this paper is to study the nature of spatial correlation of yields of agricultural crops. The focus is primarily on natural or non-anthropogenic spatial variation, patterns that cannot be explained by topography, by variety or treatment effects, or by agricultural practices. Conformal invariance implies stationarity and isotropy, and also determines the rate of decay of spatial correlations. The resulting Gaussian model is studied empirically to see whether it describes satisfactorily the pattern of spatial correlations observed in field trials of various crops. By embedding the law in a larger statistical model, a convolution of white noise and the Matérn class having a range parameter λ −1 and a smoothness parameter ν , and by gathering data of sufficient range and quantity, the model predictions were tested. Twenty-five examples of crop yields are studied, including cereals, root crops and other vegetables, nut, citrus and alfalfa yields. At the scale of typical field trials, we find that non-anthropogenic variation is reasonably close to isotropic. Furthermore, we find consistent evidence that the range parameter tends to be large and the smoothness parameter small. The large value of the range parameter confirms Fairfield Smith (Fairfield Smith 1938 J. Agric. Sci. 28 , 1–23), who found that spatial correlation in agricultural processes decreases with distance, but at a slower rate than exponential. The small value of the smoothness parameter means that, by Matérn standards, agricultural processes are rough. For each of the examples studied, the limiting model fits the data just as well as the full model, in reasonable agreement with the hypothesis of the conformal model that ( λ , ν )=(0, 0) for all crops in all seasons.

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Sanchez, N. G. "Advances in String Theory in Curved Backgrounds: A Synthesis Report." International Journal of Modern Physics A 18, no. 12 (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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Jalali-Vahid, D., H. Rahnejat, R. Gohar, and Z. M. Jin. "Prediction of oil-film thickness and shape in elliptical point contacts under combined rolling and sliding motion." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 214, no. 5 (2000): 427–37. http://dx.doi.org/10.1243/1350650001543304.

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The paper presents a numerical solution for elliptical point contact conjunctions under combined rolling and sliding motion. This condition is prevalent in many practical applications, such as rolling element bearings and conformal gears. An effective influence Newton-Raphson method is employed in local point distributed or global line distributed low-relaxation iterations. This method enables determination of the pressure distribution and film shape at high loads such as are encountered in many practical applications. Some of the numerical predictions have been validated against experimental results.

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Izmailian, Nickolay, and Ralph Kenna. "Universality and Exact Finite-Size Corrections for Spanning Trees on Cobweb and Fan Networks." Entropy 21, no. 9 (2019): 895. http://dx.doi.org/10.3390/e21090895.

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The concept of universality is a cornerstone of theories of critical phenomena. It is very well understood in most systems, especially in the thermodynamic limit. Finite-size systems present additional challenges. Even in low dimensions, universality of the edge and corner contributions to free energies and response functions is less investigated and less well understood. In particular, the question arises of how universality is maintained in correction-to-scaling in systems of the same universality class but with very different corner geometries. Two-dimensional geometries deliver the simplest such examples that can be constructed with and without corners. To investigate how the presence and absence of corners manifest universality, we analyze the spanning tree generating function on two different finite systems, namely the cobweb and fan networks. The corner free energies of these configurations have stimulated significant interest precisely because of expectations regarding their universal properties and we address how this can be delivered given that the finite-size cobweb has no corners while the fan has four. To answer, we appeal to the Ivashkevich–Izmailian–Hu approach which unifies the generating functions of distinct networks in terms of a single partition function with twisted boundary conditions. This unified approach shows that the contributions to the individual corner free energies of the fan network sum to zero so that it precisely matches that of the web. It therefore also matches conformal theory (in which the central charge is found to be c = − 2 ) and finite-size scaling predictions. Correspondence in each case with results established by alternative means for both networks verifies the soundness of the Ivashkevich–Izmailian–Hu algorithm. Its broad range of usefulness is demonstrated by its application to hitherto unsolved problems—namely the exact asymptotic expansions of the logarithms of the generating functions and the conformal partition functions for fan and cobweb geometries. We also investigate strip geometries, again confirming the predictions of conformal field theory. Thus, the resolution of a universality puzzle demonstrates the power of the algorithm and opens up new applications in the future.

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LUNA-ACOSTA, G. A. "FEYNMAN GRAPH RULES FOR IINN-INTERACTION AND MATRIX ELEMENTS FOR A SIMPLIFIED pπ0 → pπ0 MODEL IN 5-DIMENSIONAL CONFORMAL QFT". International Journal of Modern Physics A 04, № 20 (1989): 5411–32. http://dx.doi.org/10.1142/s0217751x89002314.

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Recently we reported a successful fitting of the kinematic predictions of the Mass Theory of 5-dimensional Conformal Relativity to the Hadron Spectra. We use results obtained there to study the dynamical properties of the trilinear boson-matter interaction Lagrangian implied by isospin SU(2) gauge invariance. The isovector massive gauge boson allows for two interpretations: a J = 1 field and the 5-D derivative of a J = 0 field. We construct the Feynman Graphs for the ΠNN-interaction and show that (1) any given graph is actually an infinite sum of similar graphs, one for each member of the Conformal Family Field of the virtual Hadron and (2) that the individual coupling of each of these members depends on its mass, giving rise to an effectively energy-dependent coupling. Based on these features, we speculate on the interesting possibility that Perturbation Theory may be usable for hadron processes and calculate the matrix elements for a simplified model of pπ0 → pπ0 to second order. Useful comparisons are made with the analogous treatment in ordinary QFT.

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Hamer, C. J. "Finite-Size Scaling and Effective Lagrangian Theory." Australian Journal of Physics 50, no. 6 (1997): 1051. http://dx.doi.org/10.1071/p97001.

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A brief review is given of the ‘effective Lagrangian’ approach of Leutwyler, Hasenfratz and others, which describes the behaviour at low energies or temperatures, or large distances, in lattice systems which undergo a first-order transition involving spontaneous breakdown of a continuous symmetry. Universal predictions can be given, based on a continuum field theory of the massless Goldstone bosons generated by the breakdown of the symmetry, which control the behaviour in these regimes. In particular, the finite-size scaling behaviour can be predicted, in a way very similar to the predictions of conformal invariance for a two-dimensional system at a critical point. Conversely, measurements of the finite-size scaling behaviour can give estimates of the parameters of the Goldstone bosons. These points are illustrated using data for the O(2) Heisenberg spin model in (2+1) dimensions, and the XXZ antiferromagnet on a square lattice.

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Baxter, Rodney J. "The bulk, surface and corner free energies of the anisotropic triangular Ising model." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 476, no. 2234 (2020): 20190713. http://dx.doi.org/10.1098/rspa.2019.0713.

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We consider the anisotropic Ising model on the triangular lattice with finite boundaries, and use Kaufman’s spinor method to calculate low-temperature series expansions for the partition function to high order. From these, we can obtain 108-term series expansions for the bulk, surface and corner free energies. We extrapolate these to all terms and thereby conjecture the exact results for each. Our results agree with the exactly known bulk-free energy and with Cardy and Peschel’s conformal invariance predictions for the dominant behaviour at criticality. For the isotropic case, they also agree with Vernier and Jacobsen’s conjecture for the 60 ° corners.

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Wang, Yupeng. "Fermi-Liquid Features of the One-Dimensional Luttinger Liquid." International Journal of Modern Physics B 12, no. 32 (1998): 3465–73. http://dx.doi.org/10.1142/s0217979298002817.

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We show that the one-dimensional (1D) electron systems can also be described by Landau's phenomenological Ferimi-liquid theory. Most of the known results derived from the Luttinger-liquid theory can be retrieved from the one-dimensional Fermi-liquid theory. Exact correspondence between the Landau parameters and Haldane parameters is established. The exponents of the dynamical correlation functions and the impurity problem are also discussed based on the finite size corrections of elementary excitations with the predictions of the conformal field theory, which provides a bridge between the one-dimensional Fermi-liquid and the Luttinger liquid.

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Kennedy, Tom. "Conformal Invariance and Stochastic Loewner Evolution Predictions for the 2D Self-Avoiding Walk—Monte Carlo Tests." Journal of Statistical Physics 114, no. 1/2 (2004): 51–78. http://dx.doi.org/10.1023/b:joss.0000003104.35024.f9.

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STELLA, A. L., and C. VANDERZANDE. "SURFACE CRITICAL BEHAVIOUR OF SOME TWO-DIMENSIONAL LATTICE MODELS." International Journal of Modern Physics B 04, no. 09 (1990): 1437–64. http://dx.doi.org/10.1142/s0217979290000711.

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A review is given of recent work on the ordinary surface critical behaviour of systems in two dimensions. Several models of interest in statistical mechanics are considered: Potts model, percolation, Ising clusters, ZN-model, O(n) model and polymers. Numerical results for surface exponents, obtained by suitable finite size scaling extrapolations, are discussed in the light of recent advances based on the conformal invariance approach. Surface exponents are often seen as important tests of conformal invariance predictions. In other cases these exponents provide important information for a location of the problem within the classification schemes offered by the conformal approach, and a determination of its universality class. A relevant example of the first aspect is the study of the q-state Potts model with q near 4, for which an analytical study of logarithmic scaling corrections is needed to achieve a successful test. The latter point of view applies, e.g., to the more controversial cases of polymers at the theta point and critical Ising clusters. Emphasis is put on the importance of an integrated study of both bulk and surface properties. Relevant issues, like the possible existence of analytical expressions for the indices in particular model families, or of general relationships between bulk and surface exponents, are critically discussed. The new problem of critical behaviour at fractal boundaries is also considered for random (RW) and self-avoiding walks (SAW). From the numerical analysis of this problem remarkable universalities of the surface exponents seem to emerge, which, in the case of SAW’s, are still far from being understood.

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Cappelli, Andrea, Carlo A. Trugenberger, and Guillermo R. Zemba. "W1+∞ Field Theories for the Edge Extensions in the Quantum Hall Effect." International Journal of Modern Physics A 12, no. 06 (1997): 1101–11. http://dx.doi.org/10.1142/s0217751x97000827.

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We briefly review these low-energy effective theories for the quantum Hall effect, with emphasis and language familiar to field theorists. Two models have been proposed for describing the most stable Hall plateaus (the Jain series): the multi-component Abelian theories and the minimal W1+∞ models. They both lead to a-priori classifications of quantum Hall universality classes. Some experiments already confirmed the basic predictions common to both effective theories, while other experiments will soon pin down their detailed properties and differences. Based on the study of partition functions, we show that the Abelian theories are rational conformal field theories while the minimal W1+∞ models are not.

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Chakraborty, Koushik, Farook Rahaman, and Arkopriya Mallick. "A relativistic two-fluid model of compact stars." Modern Physics Letters A 32, no. 10 (2017): 1750055. http://dx.doi.org/10.1142/s0217732317500559.

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We propose a relativistic model of compact star admitting conformal symmetry. Quark matter and baryonic matter which are considered as two different fluids, constitute the star. We define interaction equations between the normal baryonic matter and the quark matter and study the physical situations for repulsive, attractive and zero interaction between the constituent matters. The measured value of the Bag constant is used to explore the spacetime geometry inside the star. From the observed values of the masses of some compact objects, we have obtained theoretical values of the radii. Theoretical values of the radii match well with the previous predictions for such compact objects.

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Landa-Marbán, David, Wolfgang Bietenholz, and Ivan Hip. "Features of a 2d gauge theory with vanishing chiral condensate." International Journal of Modern Physics C 25, no. 10 (2014): 1450051. http://dx.doi.org/10.1142/s012918311450051x.

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The Schwinger model with Nf ≥ 2 flavors is a simple example for a fermionic model with zero chiral condensate Σ (in the chiral limit). We consider numerical data for two light flavors, based on simulations with dynamical chiral lattice fermions. We test properties and predictions that were put forward in the recent literature for models with Σ = 0, which include IR conformal theories. In particular, we probe the decorrelation of low lying Dirac eigenvalues, and we discuss the mass anomalous dimension and its IR extrapolation. Here, we encounter subtleties, which may urge caution with analogous efforts in other models, such as multi-flavor QCD.

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Zhan, Xianghao, Xiaoqing Guan, Rumeng Wu, Zhan Wang, You Wang, and Guang Li. "Discrimination between Alternative Herbal Medicines from Different Categories with the Electronic Nose." Sensors 18, no. 9 (2018): 2936. http://dx.doi.org/10.3390/s18092936.

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As alternative herbal medicine gains soar in popularity around the world, it is necessary to apply a fast and convenient means for classifying and evaluating herbal medicines. In this work, an electronic nose system with seven classification algorithms is used to discriminate between 12 categories of herbal medicines. The results show that these herbal medicines can be successfully classified, with support vector machine (SVM) and linear discriminant analysis (LDA) outperforming other algorithms in terms of accuracy. When principal component analysis (PCA) is used to lower the number of dimensions, the time cost for classification can be reduced while the data is visualized. Afterwards, conformal predictions based on 1NN (1-Nearest Neighbor) and 3NN (3-Nearest Neighbor) (CP-1NN and CP-3NN) are introduced. CP-1NN and CP-3NN provide additional, yet significant and reliable, information by giving the confidence and credibility associated with each prediction without sacrificing of accuracy. This research provides insight into the construction of a herbal medicine flavor library and gives methods and reference for future works.

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WU, Y. L., M. ZHONG та Y. B. ZUO. "B(s), D(s)→ π, K, η, ρ, K*, ω, ϕ TRANSITION FORM FACTORS AND DECAY RATES WITH EXTRACTION OF THE CKM PARAMETERS |Vub|, |Vcs|, |Vcd|". International Journal of Modern Physics A 21, № 30 (2006): 6125–72. http://dx.doi.org/10.1142/s0217751x06033209.

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A systematic calculation for the transition form factors of heavy to light mesons (B, Bs, D, Ds→ π, K, η, ρ, K*, ω, ϕ) is carried out by using light-cone sum rules in the framework of heavy quark effective field theory. The heavy quark symmetry at the leading order of 1/mQexpansion enables us to reduce the independent wave functions and establish interesting relations among form factors. Some relations hold for the whole region of momentum transfer. The meson distribution amplitudes up to twist-4 including the contributions from higher conformal spin partial waves and light meson mass corrections are considered. The CKM matrix elements |Vub|, |Vcs| and |Vcd| are extracted from some relatively well-measured decay channels. A detailed prediction for the branching ratios of heavy to light meson decays is then presented. The resulting predictions for the semileptonic and radiative decay rates of heavy to light mesons (B, Bs, D, Ds→ π, K, η, ρ, K*, ω, ϕ) are found to be compatible with the current experimental data and can be tested by more precise experiments at B-factory, LHCb, BEPCII and CLEOc.

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Park, Kyung-Ho, Joo-Gong Lee, and Adisorn Owatsiriwong. "Seepage force in a drained circular tunnel: An analytical approach." Canadian Geotechnical Journal 45, no. 3 (2008): 432–36. http://dx.doi.org/10.1139/t07-113.

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This study deals with the investigation of analytical solutions for the seepage forces acting on the lining in a drained circular tunnel under the steady-state groundwater flow condition. Two different boundary conditions (one for zero water pressure and the other for a constant total head) along the tunnel circumference are mentioned. Simple closed-form analytical solutions for seepage force along the tunnel circumference are derived in a theoretically consistent way for two different boundary conditions by using the conformal mapping technique. The seepage force predictions are compared to investigate the differences among the solutions. It is shown that the seepage forces acting on the lining should be considered for a drained tunnel and that the seepage forces greatly increase for a very deep tunnel.

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Daniewicz, S. R., J. A. Collins, and D. R. Houser. "The Stress Intensity Factor and Stiffness for a Cracked Spur Gear Tooth." Journal of Mechanical Design 116, no. 3 (1994): 697–700. http://dx.doi.org/10.1115/1.2919438.

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The stiffness of a spur gear tooth mesh controls load sharing in an operating gearset as well as vibratory properties which further dictate fatigue resistance and gear noise. A spur gear mesh consisting of a pinion with a single cracked tooth and an uncracked gear is considered. Expressions are presented which allow the determination of stress intensity factors for small through face width fatigue cracks in spur gear teeth. Predictions of tooth pair stiffness for a cracked pinion tooth and uncracked gear tooth pair are made using an analytical model. The model is based on elastic energy methods and fracture mechanics principles. The model employs a conformal mapping technique from elasticity theory, often denoted in spur gear applications as the complex potential method, in which a gear tooth is mapped onto on elastic half-plane.

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Zarrati, A. R., Yee-Chung Jin, A. Shanehsaz-zadeh, and F. Ahadi. "Potential flow solution for a free surface flow past a sudden slope change." Canadian Journal of Civil Engineering 31, no. 4 (2004): 553–60. http://dx.doi.org/10.1139/l04-021.

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An analytical model was developed to calculate the pressure distribution in a free surface flow past a sudden change in channel slope. A conformal transformation technique was used to solve the problem analytically in a way that there is no need for trial and error to find the location of the free surface. Two methods were employed for this simulation: flow at a corner and free streamline theory. It was shown that free streamline theory is more accurate. Experiments were conducted to verify the ability of the analytical model to calculate the pressure distribution in a channel with a sudden change in slope. Slope changes of 6.22°, 10°, and 15° were tested with various flow discharges. The analytical model predictions of pressure distribution along the channel bed and with depth agreed well with the experimental measurements. Pressures up to 25 times the hydrostatic pressure were experimentally measured near the point of sudden change in slope. These pressures were reproduced by the model. The analytical model predictions of the water surface profile over a ramp in a prototype spillway were compared with those of a numerical model. The comparison showed a good agreement.Key words: pressure distribution, free surface flow, analytical model, chute spillway, aerator ramp, potential flow.

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Riddle, Todd W., Alan J. Wadcock, Jin Tso, and Russell M. Cummings. "An Experimental Analysis of Vortex Trapping Techniques." Journal of Fluids Engineering 121, no. 3 (1999): 555–59. http://dx.doi.org/10.1115/1.2823504.

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An experimental verification is presented for the theoretical vortex trapping concept. A suction orifice located along one wall of a water channel test section was used to simulate a point sink to trap spanwise vortices downstream of a backward-facing step and between two parallel fences. Results from the backward-facing step geometry indicated an increase in the sink strength required to hold a vortex as the sink is positioned closer to the step, closely following previous theoretical predictions made using conformal mapping. The experimental data also showed reasonable agreement with the theoretical position for optimum vortex trapping. Flow visualization has shown a three-dimensional cross-stream effect due to bending of the forced-vortex core by suction. Results from the dual-fence geometry, on the other hand, verified the ability to use a lower level of suction for vortex trapping when compared with the backward-facing step.

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Noeske, T., and E. Ahlberg. "Step towards a hepatotoxicity warning system: Assessment of drug-induced liver injury risk by applying conformal predictions and chemical substructure alerts." Toxicology Letters 238, no. 2 (2015): S168. http://dx.doi.org/10.1016/j.toxlet.2015.08.572.

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Chang, Lisa, Hiep Duc, Yvonne Scorgie, Toan Trieu, Khalia Monk, and Ningbo Jiang. "Performance Evaluation of CCAM-CTM Regional Airshed Modelling for the New South Wales Greater Metropolitan Region." Atmosphere 9, no. 12 (2018): 486. http://dx.doi.org/10.3390/atmos9120486.

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A comprehensive evaluation of the performance of the coupled Conformal Cubic Atmospheric Model (CCAM) and Chemical Transport Model (CTM) (CCAM-CTM) for the New South Wales Greater Metropolitan Region (NSW GMR) was conducted based on modelling results for two periods coinciding with measurement campaigns undertaken during the Sydney Particle Study (SPS), namely the summer in 2011 (SPS1) and the autumn in 2012 (SPS2). The model performance was evaluated for fine particulate matter (PM2.5), ozone (O3) and nitrogen dioxide (NO2) against air quality data from the NSW Government’s air quality monitoring network, and PM2.5 components were compared with speciated PM measurements from the Sydney Particle Study’s Westmead sampling site. The model tends to overpredict PM2.5 with normalised mean bias (NMB) less than 20%, however, moderate underpredictions of the daily peak are found on high PM2.5 days. The PM2.5 predictions at all sites comply with performance criteria for mean fractional bias (MFB) of ±60%, but only PM2.5 predictions at Earlwood further comply with the performance goal for MFB of ±30% during both periods. The model generally captures the diurnal variations in ozone with a slight underestimation. The model also tends to underpredict daily maximum hourly ozone. Ozone predictions across regions in SPS1, as well as in Sydney East, Sydney Northwest and Illawarra regions in SPS2 comply with the benchmark of MFB of ±15%, however, none of the regions comply with the benchmark for mean fractional error (MFE) of 35%. The model reproduces the diurnal variations and magnitudes of NO2 well, with a slightly underestimating tendency across the regions. The MFE and normalised mean error (NME) for NO2 predictions fall well within the ranges inferred from other studies. Model results are within a factor of two of measured averages for sulphate, nitrate, sodium and organic matter, with elemental carbon, chloride, magnesium and ammonium being underpredicted. The overall performance of CCAM-CTM modelling system for the NSW GMR is comparable to similar model predictions by other regional airshed models documented in the literature. The performance of the modelling system is found to be variable according to benchmark criteria and depend on the location of the sites, as well as the time of the year. The benchmarking of CCAM-CTM modelling system supports the application of this model for air quality impact assessment and policy scenario modelling to inform air quality management in NSW.

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Kitamoto, Hiroyuki, and Yoshihisa Kitazawa. "Time dependent couplings as observables in de Sitter space." International Journal of Modern Physics A 29, no. 08 (2014): 1430016. http://dx.doi.org/10.1142/s0217751x14300166.

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We summarize and expand our investigations concerning the soft graviton effects on microscopic matter dynamics in de Sitter space. The physical couplings receive IR logarithmic corrections which are sensitive to the IR cutoff at the one-loop level. The scale invariant spectrum in the gravitational propagator at the super-horizon scale is the source of the de Sitter symmetry breaking. The quartic scalar, Yukawa and gauge couplings become time dependent and diminish with time. In contrast, the Newton's constant increases with time. We clarify the physical mechanism behind these effects in terms of the conformal mode dynamics in analogy with 2d quantum gravity. We show that they are the inevitable consequence of the general covariance and lead to gauge invariant predictions. We construct a simple model in which the cosmological constant is self-tuned to vanish due to UV–IR mixing effect. We also discuss phenomenological implications such as decaying Dark Energy and SUSY breaking at the inflation era. The quantum effect alters the classical slow roll picture in general, if the tensor-to-scalar ratio r is as small as 0.01.

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Izmailov, Ramil N., Ramis Kh Karimov, Alexander A. Potapov, and Kamal K. Nandi. "Vacuum Brans–Dicke theory in the Jordan and Einstein frames: Can they be distinguished by lensing?" Modern Physics Letters A 35, no. 37 (2020): 2050308. http://dx.doi.org/10.1142/s0217732320503083.

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Vacuum Brans-Dicke (BD) theory continues to receive widespread attention since it is consistent with solar and cosmological experiments. The theory can be self-consistently described in two frames, the Jordan frame (JF) and the conformally rescaled Einstein frame (EF), the transformations providing an easy passage from one frame to the other at the level of actions and solutions. While coordinate transformations do not change curvature properties, conformal transformations do change them leading to corresponding changes in the numerical values of observables. A previous article by Bhadra et al.[Formula: see text] did exemplify this change between JF and EF using the diagnostic of second-order light deflection. This important work leaves room for further improvements on two points, which we do here. First, the measurement of second-order effect faced technically unsurmountable difficulties even around the Sun, hence actually abandoned. Second, the comparison of quantitative values between JF and EF should be based on a common value of [Formula: see text] connecting the two frames. Keeping these in mind, we investigate a technically easier diagnostic, viz., the weak field lensing (WFL) and compare the quantitative changes at common [Formula: see text] to show that the two frames can indeed be distinguished by lensing experiments. Specifically, the predictions of light deflection, image position, total magnification and magnification factor are computed in the EF and compared with those recently obtained (by Gao et al.[Formula: see text]) directly in the JF BD class I solution. The use of the value of BD coupling constant [Formula: see text], suggested by the Cassini spacecraft solar experiment, reveals that an exceptionally high degree of accuracy is needed to experimentally rule out one or the other frame by means of WFL measurements.

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GARCÍA-BELLIDO, JUAN. "DARK MATTER WITH VARIABLE MASSES." International Journal of Modern Physics D 02, no. 01 (1993): 85–95. http://dx.doi.org/10.1142/s0218271893000076.

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String effective theories contain a dilaton scalar field which couples to gravity, matter and radiation. In general, particle masses will have different dilaton couplings. We can always choose a conformal frame in which baryons have constant masses while (nonbaryonic) dark matter have variable masses, in the context of a scalar-tensor gravity theory. We are interested in the phenomenology of this scenario. Dark matter with variable masses could have a measurable effect on the dynamical motion of the halo of spiral galaxies, which may affect cold dark matter models of galaxy formation. As a consequence of variable masses, the energy-momentum tensor is not conserved; there is a dissipative effect, due to the dilaton coupling, associated with a “dark entropy” production. In particular, if axions had variable masses they could be diluted away, thus opening the “axion window.” Assuming that dark matter with variable masses dominates the cosmological evolution during the matter era, it will affect the primordial nucleosynthesis predictions on the abundances of light elements. Furthermore, the dilaton also couples to radiation in the form of a variable gauge coupling. Experimental bounds will constrain the parameters of this model.

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Norinder, Ulf, Glenn Myatt, and Ernst Ahlberg. "Predicting Aromatic Amine Mutagenicity with Confidence: A Case Study Using Conformal Prediction." Biomolecules 8, no. 3 (2018): 85. http://dx.doi.org/10.3390/biom8030085.

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The occurrence of mutagenicity in primary aromatic amines has been investigated using conformal prediction. The results of the investigation show that it is possible to develop mathematically proven valid models using conformal prediction and that the existence of uncertain classes of prediction, such as both (both classes assigned to a compound) and empty (no class assigned to a compound), provides the user with additional information on how to use, further develop, and possibly improve future models. The study also indicates that the use of different sets of fingerprints results in models, for which the ability to discriminate varies with respect to the set level of acceptable errors.

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