Journal articles: 'Penrose Effect'

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Chen, Wein-Hong, Min-Ping Kang, and Bella Butler. "How does top management team composition matter for continual growth? Reinvestigating Penrose’s growth theory through the lens of upper echelons theory." Management Decision 57, no. 1 (January 14, 2019): 41–70. http://dx.doi.org/10.1108/md-02-2017-0147.

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Purpose Penrose’s argument regarding the managerial constraint on continual expansion over two consecutive periods is termed the “Penrose effect,” a relatively less investigated premise in Penrose’s growth theory. The purpose of this paper is to empirically re-examine the Penrose effect from the perspective of upper echelons theory and investigated how top management team (TMT) composition influences the continual growth of a firm. Design/methodology/approach This study empirically tested the hypotheses based on a sample of listed manufacturing firms operating in Taiwan, a newly industrialized economy in the Asia–Pacific region. Moderated hierarchical regression analyses were applied to test hypotheses. Findings The empirical results suggest that low TMT diversity (in terms of educational, functional and team tenure diversity) is likely to engender a situation in which the Penrose effect might occur. Additionally, the results indicate that the proportion of functional executives plays a significant role in influencing the growth trend over two consecutive periods and may soften the impact of the Penrose effect. Practical implications This paper suggests that appropriate structuring of TMTs and appropriate management of their members’ backgrounds and team tenure diversity can help firms overcome the Penrose effect and grow continually. Furthermore, the proportion of functional executives in a TMT is influential. Originality/value This paper uniquely contributes to the theoretical and empirical development of Penrose’s growth theory, upper echelons theory and resource-based view concerning managerial resources.

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Zaslavskii, O. B. "Pure electric Penrose and super-Penrose processes in the flat spacetime." International Journal of Modern Physics D 28, no. 04 (March 2019): 1950062. http://dx.doi.org/10.1142/s0218271819500627.

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Let a particle move in the flat spacetime under the action of the electric potential. If it decays to two fragments, the energy of debris can be larger than the original energy and, moreover, the efficiency of such a process can be unbounded. This effect can be considered as a limit of the Denardo–Ruffini process near the Reissner–Nordström black hole when the gravitational constant and/or black hole mass tend to zero. There are scenarios in which the energy of debris at infinity is much larger than the initial one. Comparison with other close but distinct effects is discussed.

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Cyrenne, Philippe. "Dual Distribution and the Penrose Effect." International Journal of the Economics of Business 21, no. 1 (January 2, 2014): 55–76. http://dx.doi.org/10.1080/13571516.2013.800325.

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&NA;. "Psychiatric Hospital Downsizing and the Penrose Effect." Journal of Nervous and Mental Disease 184, no. 11 (November 1996): 708–9. http://dx.doi.org/10.1097/00005053-199611000-00009.

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Rahim, Rehana, and Khalid Saifullah. "Effect of charge and deformation parameter on energy extraction in charged non-Kerr black holes." International Journal of Modern Physics D 28, no. 16 (October 16, 2019): 2040012. http://dx.doi.org/10.1142/s021827182040012x.

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We analyze the charged Johannsen–Psaltis black hole for energy extraction via the Penrose process. Efficiency of the Penrose process is found to be dependent on the deformation parameter of the metric and charge. Doing the calculations numerically, we find that, in the nonextremal limit, presence of charge leads to lesser efficiency than the Kerr. In the extremal cases with negative deformation parameter, charge leads to a very high efficiency, higher than that of the Kerr and Johannsen–Psaltis black holes.

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Luo, D., Q. G. Du, H. T. Dai, X. H. Zhang, and X. W. Sun. "Temperature effect on lasing from Penrose photonic quasicrystal." Optical Materials Express 4, no. 6 (May 13, 2014): 1172. http://dx.doi.org/10.1364/ome.4.001172.

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Goerzen, Anthony, and Paul W. Beamish. "The Penrose effect: “Excess” expatriates in multinational enterprises." Management International Review 47, no. 2 (March 2007): 221–39. http://dx.doi.org/10.1007/s11575-007-0013-5.

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Thompson, R. Steve. "The franchise life cycle and the Penrose effect." Journal of Economic Behavior & Organization 24, no. 2 (July 1994): 207–18. http://dx.doi.org/10.1016/0167-2681(94)90027-2.

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Grib, A. A., and Yu V. Pavlov. "Static Limit and Penrose Effect in Rotating Reference Frames." Theoretical and Mathematical Physics 200, no. 2 (August 2019): 1117–25. http://dx.doi.org/10.1134/s004057791908004x.

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PALPACELLI, SILVIA, and SAURO SUCCI. "NUMERICAL SIMULATION OF QUANTUM STATE REDUCTION IN BOSE–EINSTEIN CONDENSATES WITH ATTRACTIVE INTERACTIONS." International Journal of Modern Physics C 21, no. 05 (May 2010): 629–46. http://dx.doi.org/10.1142/s0129183110015385.

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Following an idea first proposed by Penrose in 1996 to explain the problem of quantum state reduction as a gravitational effect, Moroz, Penrose and Tod1 have shown that quantum state reduction due to gravitational interactions could take place in about one second for the case of 1011 nucleons. However, keeping 1011 nucleons together in a quantum macroscopic state does not appear to be feasible as yet. The closest physical system to such a situation is provided by Bose–Einstein condensates (BEC) with attractive interactions. We present numerical simulations of the Schrödinger–Newton equations, which show that an attractive BEC with 103 atoms would yield a decorrelation time of the order of 10-2 seconds. Hence, a "Penrose-like" reduction, induced by BEC attractive interaction instead of gravity, might be observable and possibly monitored in current BEC experiments with attractive interactions.

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Grib, Andrey A., and Yuri V. Pavlov. "Particles with Negative Energies in Nonrelativistic and Relativistic Cases." Symmetry 12, no. 4 (April 3, 2020): 528. http://dx.doi.org/10.3390/sym12040528.

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States of particles with negative energies are considered for the nonrelativistic and relativistic cases. In the nonrelativistic case it is shown that the decay close to the attracting center can lead to the situation similar to the Penrose effect for a rotating black hole when the energy of one of the fragments is larger than the energy of the initial body. This is known as the Oberth effect in the theory of the rocket movement. The realizations of the Penrose effect in the non-relativistic case in collisions near the attracting body and in the evaporation of stars from star clusters are indicated. In the relativistic case similar to the well known Penrose process in the ergosphere of the rotating black hole it is shown that the same situation as in ergosphere of the black hole occurs in rotating coordinate system in Minkowski space-time out of the static limit due to existence of negative energies. In relativistic cases differently from the nonrelativistic ones, the mass of the fragment can be larger than the mass of the decaying body. Negative energies for particles are possible in the relativistic case in cosmology of the expanding space when the coordinate system is used with a nondiagonal term in metrical tensor of the space-time. Friedmann metrics for three cases: open, close and quasieuclidian, are analyzed. The De Sitter space-time is shortly discussed.

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Grib, A. A., and Yu V. Pavlov. "Erratum to: Static Limit and Penrose Effect in Rotating Reference Frames." Theoretical and Mathematical Physics 201, no. 1 (October 2019): 1541. http://dx.doi.org/10.1134/s0040577919100118.

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13

Tan, Danchi, and Joseph T. Mahoney. "The dynamics of Japanese firm growth in U.S. Industries: The Penrose effect." Management International Review 47, no. 2 (March 2007): 259–79. http://dx.doi.org/10.1007/s11575-007-0015-3.

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GREZIA, ELISABETTA DI, and GIAMPIERO ESPOSITO. "NON-COMMUTATIVE KERR BLACK HOLE." International Journal of Geometric Methods in Modern Physics 08, no. 03 (May 2011): 657–68. http://dx.doi.org/10.1142/s0219887811005324.

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This paper applies the first-order Seiberg–Witten map to evaluate the first-order non-commutative Kerr tetrad. The classical tetrad is taken to follow the locally non-rotating frame prescription. We also evaluate the tiny effect of non-commutativity on the efficiency of the Penrose process of rotational energy extraction from a black hole.

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Stiles, G. S., and Dong-Lih Denq. "On the Effect of Noise on the Moore-Penrose Generalized Inverse Associative Memory." IEEE Transactions on Pattern Analysis and Machine Intelligence PAMI-7, no. 3 (May 1985): 358–60. http://dx.doi.org/10.1109/tpami.1985.4767667.

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Sfarti, A. "The appearance of the objects rolling at relativistic speeds." Canadian Journal of Physics 86, no. 12 (December 1, 2008): 1437–41. http://dx.doi.org/10.1139/p08-083.

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In the late 1950s Terrell and Penrose produced a series of papers dealing with the appearance of the rapidly moving bodies while in rectilinear motion as photographed by a simple, pinhole camera. A few more articles on the same subject followed, for example, Penrose showed that a sphere is always seen having an exactly circular outline, at any velocity, at any distance and for any line of sight. In the present paper, we will deal with a more complex type of motion, the combination of translation and rotation that can be seen when observing the wheels of a vehicle passing by. Since Terrell and Penrose wrote their papers, great advances in the camera simulation via computer representation have been made. The field that deals with the simulation of realistic cameras via computers is called ray tracing. In the current paper, we will combine two different disciplines, relativistic physics and three-dimensional graphics to derive new results. Our paper is divided in two main parts, in the first half, we will derive the relativistic equations for rolling motion without slip and we will make some connections with the physical requirements of a relativistic ray-tracing algorithm. In the second half, we will review the foundations of classical ray-tracing algorithms and we will introduce the additional features for operation at relativistic speeds. We will demonstrate an interesting self-canceling effect of the relativistic Doppler shift on the colors wavelengths of the moving object.PACS No.: 03.30.+p

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PERVUSHIN, V. N., and V. I. SMIRICHINSKI. "CONFORMAL SYMMETRY AND HIGGS EFFECT IN QUANTUM COSMOLOGY." Modern Physics Letters A 13, no. 02 (January 20, 1998): 119–31. http://dx.doi.org/10.1142/s0217732398000164.

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We point out an important role of conformal invariant observables in the formulation of quantum cosmology with a normalizable wave function which bears a direct relationship to the Friedmann observational evolution of the Universe (with redshift and Hubble law). Conformal invariant field variables allow us to establish relation between standard cosmological models and quantum field theory actions. The conformal symmetry principle excludes the Higgs potential from the Weinberg–Salam model and includes the Penrose–Chernikov–Tagirov term. In the conformal version of the standard model for electroweak interaction unified with the Einstein gravity, the Higgs field is absorbed by the space metric so that the elementary particle masses and the evolution of the Universe have one and the same origin. In the flat-space limit we got the σ-version of the Weinberg–Salam model without the Higgs particle-like excitations.

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Chen, Wein-Hong Emily, Min-Ping Kang, and Chun-Neng Peng. "Top Management Team Experiences and the Growth of a Firm: The Penrose Effect Revisited." Academy of Management Proceedings 2013, no. 1 (January 2013): 13444. http://dx.doi.org/10.5465/ambpp.2013.13444abstract.

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Matveev, V. N., and O. V. Matvejev. "The Terrell-Penrose effect when photographing a sphere at rest with a moving camera." Journal of Physics: Conference Series 1251 (June 2019): 012035. http://dx.doi.org/10.1088/1742-6596/1251/1/012035.

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Uzawa, H. "An endogenous rate of time preference, the Penrose effect, and dynamic optimality of environmental quality." Proceedings of the National Academy of Sciences 93, no. 12 (June 11, 1996): 5770–76. http://dx.doi.org/10.1073/pnas.93.12.5770.

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Indelicato, Giuliana, Tom Keef, Paolo Cermelli, David G. Salthouse, Reidun Twarock, and Giovanni Zanzotto. "Structural transformations in quasicrystals induced by higher dimensional lattice transitions." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2141 (February 8, 2012): 1452–71. http://dx.doi.org/10.1098/rspa.2011.0680.

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We study the structural transformations induced, via the cut-and-project method, in quasicrystals and tilings by lattice transitions in higher dimensions, with a focus on transition paths preserving at least some symmetry in intermediate lattices. We discuss the effect of such transformations on planar aperiodic Penrose tilings, and on three-dimensional aperiodic Ammann tilings with icosahedral symmetry. We find that locally the transformations in the aperiodic structures occur through the mechanisms of tile splitting, tile flipping and tile merger, and we investigate the origin of these local transformation mechanisms within the projection framework.

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Jimba, Yoji, and Hiroshi Miyazaki. "Size Effect and Aperture Configuration Dependence of Extraordinary Optical Transmission through Penrose Metal Hole Arrays in the Terahertz Region." IEEJ Transactions on Sensors and Micromachines 135, no. 11 (2015): 402–7. http://dx.doi.org/10.1541/ieejsmas.135.402.

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Cleland, John, and Jerome van Ginneken. "Maternal schooling and childhood mortality." Journal of Biosocial Science 21, S10 (1989): 13–34. http://dx.doi.org/10.1017/s0021932000025244.

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There is nothing new about the belief that the spread of education with its influence on knowledge and outlook is a central force behind the demographic transition. In 1934 Penrose wrote: ‘when a community has gained the knowledge and acquired the habits necessary to reduce the death rate it will sooner or later gain the knowledge and acquire the habits necessary to reduce the birth rate. There may be time lag between the two processes, but both of them in a large share are the outcome of education’ (Penrose, 1934). It is thus surprising that investigation of the specific influence of parental education on the mortality of children in developing countries was neglected until Caldwell's (1979) analysis of survey data from Ibadan, Nigeria, which demonstrated that mother's education was a more decisive determinant of child survival than other family characteristics such as husband's occupation and education. Other studies followed this influential investigation. The greater contribution to mortality decline of educational advance compared to health care provision, it has been argued, is a contribution to the development versus medical technology debate (Mosley, 1985). Inevitably the beginnings of a counter-reaction may be discerned. Caldwell (1986) stressed that the influence of education should not be considered in isolation from the wider context, while Cooksey et al. (1986, unpublished) consider that the effect of maternal education may have been exaggerated.

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Vidal, Elena, and Will Mitchell. "Virtuous or vicious cycles? The role of divestitures as a complementary Penrose effect within resource-based theory." Strategic Management Journal 39, no. 1 (November 13, 2017): 131–54. http://dx.doi.org/10.1002/smj.2701.

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Prakasa, Aditya Guntur. "Analisis pengaruh growth terhadap profit pada perusahaan manufaktur terbuka di Indonesia: Analisis model panel data dinamis." JURNAL DINAMIKA EKONOMI PEMBANGUNAN 2, no. 3 (February 23, 2020): 53. http://dx.doi.org/10.14710/jdep.2.3.53-66.

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Growth will affect profitability of a firm. There is ongoing debate about how growth will affect profit both theoritically and empirical results. Classical hypothesis predict growth will affect profit positively. Growth can improve firm profitability because the effect from economies of scale and the learning curve effect that makes the production process and the cost of production become more efficient. Behavioral hypothesis predict growth will affect profit negatively because of principal agent problem, managerial constraints, penrose effect or diseconomies of scale. The objective of this study is to examine the effect of growth to profit based on the argument between Classical hypothesis and behavioral hypothesis. This study used dynamics panel data with generalized method of moments (GMM) as estimator. This study observed 82 publicly listed manufacturing firm in Indonesia consist of nine periods from 2009 to 2018 resulting in 656 observations. Empirical result shows that growth will affect profit negatively. Thus, prove the behavioral hypothesis that predict negative influence of growth to profit.

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Tan, Danchi, and Joseph T. Mahoney. "Examining the Penrose effect in an international business context: the dynamics of Japanese firm growth in US industries." Managerial and Decision Economics 26, no. 2 (2005): 113–27. http://dx.doi.org/10.1002/mde.1212.

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Watson, Luke. "Corporate Social Responsibility, Tax Avoidance, and Earnings Performance." Journal of the American Taxation Association 37, no. 2 (January 1, 2015): 1–21. http://dx.doi.org/10.2308/atax-51022.

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ABSTRACT I investigate the influence of pretax earnings performance on the relation between corporate social responsibility (CSR) and tax avoidance. Prior studies of the relation between CSR and tax avoidance find mixed results. Based on slack resource theory (Penrose 1959), I predict and find that the relation between CSR and tax avoidance is moderated by earnings performance. The evidence shows that a lack of social responsibility is positively associated with tax avoidance in firms with low current or future earnings performance, but this effect is diminished when current or future earnings performance is high. There is some evidence that corporate social responsibility is positively associated with tax avoidance when current or future earnings performance is low but, again, the effect disappears when current or future earnings performance is high. Overall, my results suggest that attention to the demands of non-shareholder stakeholders is curtailed when firms face scarce resources.

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JIMBA, YOJI, and HIROSHI MIYAZAKI. "Size Effect and Aperture Configuration Dependence of Extraordinary Optical Transmission through Penrose Metal Hole Arrays in the Terahertz Region." Electronics and Communications in Japan 99, no. 12 (November 17, 2016): 12–19. http://dx.doi.org/10.1002/ecj.11908.

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Zaslavskii, Oleg B. "New Scenarios of High-Energy Particle Collisions Near Wormholes." Universe 6, no. 12 (November 30, 2020): 227. http://dx.doi.org/10.3390/universe6120227.

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We suggest two new scenarios of high-energy particle collisions in the background of a wormhole. In scenario 1, the novelty consists of the fact that the effect does not require two particles coming from different mouths. Instead, all such scenarios of high energy collisions develop, when an experimenter sends particles towards a wormhole from the same side of the throat. For static wormholes, this approach leads to indefinitely large energy in the center of mass. For rotating wormholes, it makes possible the super-Penrose process (unbounded energies measured at infinity). In scenario 2, one of colliding particles oscillates near the wormhole throat from the very beginning. In this sense, scenario 2 is intermediate between the standard one and scenario 1 since the particle under discussion does not come from infinity at all.

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Jammoussi, Imen, and Mounir Ben Nasr. "A Hybrid Method Based on Extreme Learning Machine and Self Organizing Map for Pattern Classification." Computational Intelligence and Neuroscience 2020 (August 25, 2020): 1–9. http://dx.doi.org/10.1155/2020/2918276.

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Extreme learning machine is a fast learning algorithm for single hidden layer feedforward neural network. However, an improper number of hidden neurons and random parameters have a great effect on the performance of the extreme learning machine. In order to select a suitable number of hidden neurons, this paper proposes a novel hybrid learning based on a two-step process. First, the parameters of hidden layer are adjusted by a self-organized learning algorithm. Next, the weights matrix of the output layer is determined using the Moore–Penrose inverse method. Nine classification datasets are considered to demonstrate the efficiency of the proposed approach compared with original extreme learning machine, Tikhonov regularization optimally pruned extreme learning machine, and backpropagation algorithms. The results show that the proposed method is fast and produces better accuracy and generalization performances.

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Loke, Andrew Ter Ern. "IS AN INFINITE TEMPORAL REGRESS OF EVENTS POSSIBLE?" Think 11, no. 31 (2012): 105–22. http://dx.doi.org/10.1017/s1477175612000061.

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Issues concerning the ultimate origins of the universe have generated huge public interest recently. It began with the publication of The Grand Design by Stephen Hawking and Leonard Mlodinow, in which the authors claim that, because there is a law like gravity, the universe can and will create itself from nothing, and thus there is no role for God. This has prompted heated responses from scientists, philosophers, and religious leaders in the media, many of them asking, in effect, ‘where that law came from’. Subsequently, Roger Penrose released his new book Cycles of Time, arguing that what came before the Big Bang was the end of another universe, prompting the question whether there is an infinite temporal regress of universes or not. These discussions make it very timely to examine afresh whether an infinite temporal regress of events is possible.

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Uzawa, Hirofumi. "Intergenerational equity and dynamic duality principles." Discrete Dynamics in Nature and Society 7, no. 4 (2002): 249–59. http://dx.doi.org/10.1155/s1026022602000286.

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The concept of intergenerational equity concerning intertemporal paths of consumption and capital accumulation is introduced and the analysis of the dynamic processes of capital accumulation and changes in environmental quality that are intergenerationally equitable is developed. The analysis is based upon the dynamic duality principles, as originally developed by Koopmans and Uzawa, and later extended to the case involving environmental quality.A time-path of consumption and capital accumulation is defined intergenerationally equitable when it is dynamically efficient and, at the same time, the imputed price of each kind of capital, either private capital, or social overhead capital, is identical over time. The existence of an intergenerationally equitable time-path of consumption and capital accumulation is guaranteed when the processes of various kind of capital are subject to the Penrose effect, exhibiting the law of diminishing marginal rates of investment capital accumulation.

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GRIB, A. A., and YU V. PAVLOV. "DO ACTIVE GALACTIC NUCLEI CONVERT DARK MATTER INTO VISIBLE PARTICLES?" Modern Physics Letters A 23, no. 16 (May 30, 2008): 1151–59. http://dx.doi.org/10.1142/s0217732308027072.

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The hypothesis that dark matter consists of superheavy particles with the mass close to the Grand Unification scale is investigated. These particles were created from vacuum by the gravitation of the expanding Universe and their decay led to the observable baryon charge. Some part of these particles with the lifetime larger than the time of breaking of the Grand Unification symmetry became metastable and survived up to the modern time as dark matter. However, in active galactic nuclei due to large energies of dark matter particles swallowed by the black hole and the possibility of the Penrose process for rotating black hole the opposite process can occur. Dark matter particles become interacting. Their decay on visible particles at the Grand Unification energies leads to the flow of ultra high energy cosmic rays observed by the Auger group. Numerical estimates of the effect leading to the observable numbers are given.

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Mathur, A., R. C. Russell, A. C. Roth, and D. Wagahoff. "Ultrastructural Evaluation of Ischemic Skeletal Muscle Reperfused with Oxygen Free Radical Scavengers." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 262–63. http://dx.doi.org/10.1017/s0424820100103371.

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Skeletal muscle is very sensitive to ischemia. A prolonged preoperative ischemic interval decreases the chances for successful replantation of an amputated limb. Recent experimental work has implicated toxic oxygen free radicals produced during reperfusion of ischemic tissue to be responsible for some of the observed deleterious cellular changes. Selected oxygen free radical scavengers have been used to increase skeletal muscle survival following total ischemia. This study examined the effect of systemic administration of a superoxide free radical scavenger, superoxide dismutase (SOD), and a hydroxyl radical scavenger, dimethylsulfoxide (DMSO) just prior to reperfusion, on the ultrastructure and function of ischemic rabbit anterior tibialis muscle.White male New Zealand rabbits were used for this study. The right hind limb of each rabbit was made ischemic by dissecting and clamping the femoral artery and vein proximal to the bifurcation of the profundus artery and vein. A penrose tourniquet was also placed around the knee. The animals were divided into groups subjected to either 5 or 8 hours of ischemia.

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He, Z. C., X. Y. Lin, and Eric Li. "A Novel Method for Load Bounds Identification for Uncertain Structures in Frequency Domain." International Journal of Computational Methods 15, no. 06 (September 2018): 1850051. http://dx.doi.org/10.1142/s0219876218500512.

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A novel method for load bounds identification for uncertain structures is proposed in the frequency domain. The uncertain parameters are assumed to locate in their intervals and only their bounds rather than their precise information are needed. To quantitatively describe the effect of the interval uncertainty on the load identification in the frequency ranges, the interval extension is then introduced in the frequency response function (FRF)-based least squares approach. Therefore, the load bounds are determined through the summation of the two separate parts including the midpoint part and the perturbed part of the load. The midpoint part is computed by using the Moore–Penrose pseudo-inversion and the perturbed part is transformed into the first derivatives of the midpoint load with respect to the uncertain parameters by applying the truncated total least squares (TTLS). Two numerical examples are investigated to validate that the proposed method is very effective to predict the load bounds for the uncertain structure in frequency domain.

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Roedersheimer, Mark. "Solving the Measurement Problem and then Steppin’ Out over the Line Riding the Rarest Italian: Crossing the Streams to Retrieve Stable Bioactivity in Majorana Bound States of Dialy zed Human Platelet Lysates." Open Neurology Journal 9, no. 1 (June 26, 2015): 32–44. http://dx.doi.org/10.2174/1874205x01509010032.

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Exhaustive dialysis (ED) of lysed human platelets against dilute HCl yields stable angiogenic activity. Dialysis against a constrained external volume, with subsequent relaxation of the separation upon opening the dialysis bag, produces material able to maintain phenotypes and viability of human cells in culture better than ED material. Significant graded changes in MTT viability measurement tracked with external volume. The presence of elements smaller than the MW cutoff, capable of setting up cycling currents initiated by oriented flow of HCl across the membrane, suggests that maturation of bioactivity occurred through establishment of a novel type of geometric phase. These information-rich bound states fit recent descriptions of topological order and Majorana fermions, suggesting relevance in testing Penrose and Hameroff’s theory of Orchestrated Objective Reduction, under conditions more general, and on finer scales, than those dependent on tubulin protein. The Berry curvature appears to be a good tool for building a general field theory of physiologic stress dependent on the quantum Hall effect. A new form of geometric phase, and an associated “geometric” quantum Hall effect underlying memory retrieval, dependent on the rate of path traversal and reduction from more than two initial field influences is described.

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MITRA, ABHAS. "DOES PRESSURE ACCENTUATE GENERAL RELATIVISTIC GRAVITATIONAL COLLAPSE AND FORMATION OF TRAPPED SURFACES?" International Journal of Modern Physics D 22, no. 05 (April 2013): 1350021. http://dx.doi.org/10.1142/s0218271813500211.

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It is widely believed that though pressure resists gravitational collapse in Newtonian gravity, it aids the same in general relativity (GR) so that GR collapse should eventually be similar to the monotonous free fall case. But we show that, even in the context of radiationless adiabatic collapse of a perfect fluid, pressure tends to resist GR collapse in a manner which is more pronounced than the corresponding Newtonian case and formation of trapped surfaces is inhibited. In fact there are many works which show such collapse to rebound or become oscillatory implying a tug of war between attractive gravity and repulsive pressure gradient. Furthermore, for an imperfect fluid, the resistive effect of pressure could be significant due to likely dramatic increase of tangential pressure beyond the "photon sphere." Indeed, with inclusion of tangential pressure, in principle, there can be static objects with surface gravitational redshift z → ∞. Therefore, pressure can certainly oppose gravitational contraction in GR in a significant manner in contradiction to the idea of Roger Penrose that GR continued collapse must be unstoppable.

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Dolan, Sam R. "Geometrical optics for scalar, electromagnetic and gravitational waves on curved spacetime." International Journal of Modern Physics D 27, no. 11 (August 2018): 1843010. http://dx.doi.org/10.1142/s0218271818430101.

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The geometrical-optics expansion reduces the problem of solving wave equations to one of the solving transport equations along rays. Here, we consider scalar, electromagnetic and gravitational waves propagating on a curved spacetime in general relativity. We show that each is governed by a wave equation with the same principal part. It follows that: each wave propagates at the speed of light along rays (null generators of hypersurfaces of constant phase); the square of the wave amplitude varies in inverse proportion to the cross-section of the beam; and the polarization is parallel-propagated along the ray (the Skrotskii/Rytov effect). We show that the optical scalars for a beam, and various Newman–Penrose scalars describing a parallel-propagated null tetrad, can be found by solving transport equations in a second-order formulation. Unlike the Sachs equations, this formulation makes it straightforward to find such scalars beyond the first conjugate point of a congruence, where neighboring rays cross, and the scalars diverge. We discuss differential precession across the beam which leads to a modified phase in the geometrical-optics expansion.

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Zhang, Yuan, and Sijie Gao. "Testing cosmic censorship conjecture near extremal black holes with cosmological constants." International Journal of Modern Physics D 23, no. 05 (April 30, 2014): 1450044. http://dx.doi.org/10.1142/s0218271814500448.

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It has been shown previously that an extremal Reissner–Nordström or an extremal Kerr black hole cannot be overcharged or overspun by a test particle, if radiative and self-force effects are neglected. In this paper, we consider extremal charged and rotating black holes with cosmological constants. By studying the motion of test particles, we find the following results: An extremal Reissner–Nordström anti-de Sitter (RN–AdS) black hole can be overcharged by a test particle but an extremal Reissner–Nordström de Sitter (RN–dS) black hole cannot be overcharged. We also show that both extremal Kerr–de Sitter (Kerr–dS) and Kerr–anti-de Sitter (Kerr–AdS) black holes can be overspun by a test particle, implying a possible breakdown of the cosmic censorship conjecture. For the Kerr–AdS case, the overspinning requires that the energy of the particle be negative, a reminiscent of the Penrose process. In contrast to the extremal RN and Kerr black holes, in which cases the cosmic censorship is upheld, our results suggest some subtle relations between the cosmological constants and the cosmic censorship. We also discuss the effect of radiation reaction for the Kerr–dS case and find that the magnitude of energy loss due to gravitational radiation may not be enough to prevent the violation of the cosmic censorship.

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Lange, Kezia J., and Melvin G. McInnis. "Studies of Anticipation in Bipolar Affective Disorder." CNS Spectrums 7, no. 3 (March 2002): 196–202. http://dx.doi.org/10.1017/s1092852900017569.

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ABSTRACTAnticipation refers to the increase in disease severity or decrease in age of onset in successive generations. The concept evolved from the theories and dogma of degeneration that were pervasive in psychiatry and medicine in the late 19th century and into the early 20th century. The term was set aside with the criticism of geneticist Lionel Penrose, who argued that anticipation was the result of ascertainment biases. The renewed interest in anticipation followed the identification of its molecular genetic basis in the form of unstable trinucleotide repeats. Subsequently, several diseases have been studied clinically for the presence of anticipation. Although anticipation has been identified in many diseases, including bipolar disorder, only diseases showing a pattern of progressive neurodegeneration have been associated with unstable trinucleotide repeats. This review summarizes the research on anticipation in bipolar disorder and other secular trends in the patterns of the illness such as the cohort effect. The changing nature of bipolar disorder is likely to be a result of combined influences from several genes, some of which are likely to be in a state of flux, as well as environmental or cultural forces that converge to give the clinical picture of anticipation.

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Corral Bustamante, R. Leticia, Evelyn M. Rodríguez Corral, José Nino Hernández Magdaleno, and Gilberto Irigoyen Chávez. "Energy Transfer and Fluid Flow around a Massive Astrophysical Object." Defect and Diffusion Forum 348 (January 2014): 189–215. http://dx.doi.org/10.4028/www.scientific.net/ddf.348.189.

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In this work it is presented the modeling and simulation of energy transfer and fluid flow of a stationary spherical arrangement of particles surrounding a gravitational body such as an astrophysical object that carries the curvature of space-time continuum in general relativity, taking into account the thermodynamics of the second law. This model also predicts the drag of space and time around an astrophysical object as it rotates, with results close to the experimental data reported by other authors. To model the energy transfer of the mass and the fluid flow in the space-time, it is used a 4-dimensional system. In order to make measurements of entropy in the arrow of time (past-present), tensors in General Relativity were used to calculate this thermodynamic quantity and with this, the big bang ́s low entropy condition in phase space of coarse graining (Hawking ́s box), according to Weyl curvature hypothesis (WCH) of Roger Penrose. Contribution of this paper is presented by tensors which carry information that has to do with something as non-distortion effect in fluid flow around the astrophysical object and the low entropy condition that is believed to exist in the past, in the big bang;what leads us to search for a new physical-mathematical science to continue. At this point, the Einstein field equations are out of context, which leads us to conclude that it is necessary a mathematical science that allows us to make calculations to rescue lost information due to collapse of matter to a black hole. This math should allow us to clear up physical phenomena (like origin of the universe) and their relationship, with the objective of unifying theories that lead to a physical science without uncertainties, as at the present time. In this regard, we propose a metric in hyperbolic coodinates to build a physical wormhole shaped object where gravitational bodies can be housed that allow us to link the past entropy with the present entropy according to the second law of thermodynamics, as a kind of mathematical space or alternative model to compensate in some way, the link between WCH and the phase space volume of the Hawking's box, and the link between WCH and the quantum-mechanical state-vector reduction, , proposed by Penrose which still have not been determined by any author. Nomenclature

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Navarro, Félix V., Wayne C. Youngquis, and William Compton. "Estimación de varianzas genéticas en maíz a partir de líneas S1 y S2." Agronomía Mesoamericana 3 (June 22, 2016): 9. http://dx.doi.org/10.15517/am.v3i0.25198.

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The analysis of lines S-l and S-2 and the regression of the measurements of the S-2 on their corresponding S-l were used to estimate the existing genetic variability in a Nebraska Stiff Stalk Synthetic (NSS) corn population at two localities, Mead and Lincoln, Nebraska-USA. A significant genetic variability was found in NSS for grain yield, days to blooming, ear and plant height, grain humidity and lodging percentage. The S-2 lines showed more frequent interaction of genotypes x environment than their S-l. In the wide sense, the heritability for the yield calculated by the analysis of variance of S-2 lines was larger than the one based on the regression of the S-2 on S-l (60 and 42%, respectively). Eight models, originated from Cockerham (1983), were used to identify the existing types of genetic variabilities. The inverse matrix method was used to estimate the parameters of genetic variability when the used co-variances gave a non-singular square matrix. The generalized inverse method o Moore-Penrose was used when the models showed a rectangular matrix. Usually, the best model was the one which estimated the additive variance only. Often times, no consistent covariance estimates were obtained among additive and dominant homocygotic (D-1) effects. For it, we could not infer to what the S-l family selection effect could be on the behavior of the resulting line crosses. The expected genetic gain per selection cycle for yield of S-2 families was 11.4%.

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Stephen, N. G. "Transfer matrix analysis of the elastostatics of one-dimensional repetitive structures." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 462, no. 2072 (February 28, 2006): 2245–70. http://dx.doi.org/10.1098/rspa.2006.1669.

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Transfer matrices are used widely for the dynamic analysis of engineering structures, increasingly so for static analysis, and are particularly useful in the treatment of repetitive structures for which, in general, the behaviour of a complete structure can be determined through the analysis of a single repeating cell, together with boundary conditions if the structure is not of infinite extent. For elastostatic analyses, non-unity eigenvalues of the transfer matrix of a repeating cell are the rates of decay of self-equilibrated loading, as anticipated by Saint-Venant's principle. Multiple unity eigenvalues pertain to the transmission of load, e.g. tension, or bending moment, and equivalent (homogenized) continuum properties, such as cross-sectional area, second moment of area and Poisson's ratio, can be determined from the associated eigen- and principal vectors. Various disparate results, the majority new, others drawn from diverse sources, are presented. These include calculation of principal vectors using the Moore–Penrose inverse, bi- and symplectic orthogonality and relationship with the reciprocal theorem, restrictions on complex unity eigenvalues, effect of cell left-to-right symmetry on both the stiffness and transfer matrices, eigenvalue veering in the absence of translational symmetry and limitations on possible Jordan canonical forms. It is shown that only a repeating unity eigenvalue can lead to a non-trivial Jordan block form, so degenerate decay modes cannot exist. The present elastostatic analysis complements Langley's (Langley 1996 Proc. R. Soc. A 452 , 1631–1648) transfer matrix analysis of wave motion energetics.

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Broerse, Jack, Rongxin Li, and Roderick Ashton. "Ambiguous Pictorial Depth Cues and Perceptions of Nonrigid Motion in the Three-Loop Figure." Perception 23, no. 9 (September 1994): 1049–62. http://dx.doi.org/10.1068/p231049.

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The three-loop figure is a two-dimensional (2-D) pattern that generates (mis)perceptions of nonrigid three-dimensional (3-D) structure when rotated about its centre. Such observations have been described as counterexamples to the principle whereby a moving object is presumed to be rigid, provided that a rigid interpretation is possible (ie the ‘rigidity constraint’). In the present investigation we demonstrated that stationary three-loop figures exhibit many of the classic properties of multistable/ambiguous figures, with any one of several possible 3-D configurations being reported at any one instant. Further investigation revealed that perceived nonrigidity during rotation was markedly reduced (and rigidity enhanced) when the figure was modified with static pictorial depth cues (eg shading, interposition). These cues had no effect on the overall proportion of time that observers reported 3-D organisations in stationary versions of the figure, but significantly reduced the frequency of perceptual reorganisation, and increased the duration for reporting a particular organisation. Since each of the perceived 3-D structures in a stationary ambiguous 2-D figure has a unique kinetic counterpart (ie rigid transformation), we attribute the nonrigid structure perceived when the figure rotates to the integration of these otherwise inconsistent kinetic components; and have further illustrated this with modified versions of a Penrose impossible triangle. Under kinetic versions of the classical size/distance invariance hypothesis, the rigidity constraint may be considered to represent a special instance of size/shape constancy, in which case counterexamples involving (mis)perceptions of nonrigid structure are comparable to other well-known exceptions to such principles of minimum object change (eg classical illusions).

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Novick-Cohen, A., and Songmu Zheng. "The Penrose–Fife-type equations: counting the one-dimensional stationary solutions." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 126, no. 3 (1996): 483–504. http://dx.doi.org/10.1017/s0308210500022873.

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A method for counting the solutions for Penrose–Fife-type phase field equations is derived. The method used is similar to that developed recently for obtaining a precise count for the number of solutions for the Cahn–Hilliard equation [9], and is based on the derivation of an extended system of Picard–Fuchs equations as well as on estimates obtained in [11]. The Penrose–Fife-type phase field equations represent a thermodynamically consistent model for phase separation of a conserved order parameter (typically concentration) in binary systems in which latent heat effects are important in the phase separation process.

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Ali, Mohsin, Yong Zhang, Awais Rasheed, Jiankang Wang, and Luyan Zhang. "Genomic Prediction for Grain Yield and Yield-Related Traits in Chinese Winter Wheat." International Journal of Molecular Sciences 21, no. 4 (February 17, 2020): 1342. http://dx.doi.org/10.3390/ijms21041342.

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Genomic selection (GS) is a strategy to predict the genetic merits of individuals using genome-wide markers. However, GS prediction accuracy is affected by many factors, including missing rate and minor allele frequency (MAF) of genotypic data, GS models, trait features, etc. In this study, we used one wheat population to investigate prediction accuracies of various GS models on yield and yield-related traits from various quality control (QC) scenarios, missing genotype imputation, and genome-wide association studies (GWAS)-derived markers. Missing rate and MAF of single nucleotide polymorphism (SNP) markers were two major factors in QC. Five missing rate levels (0%, 20%, 40%, 60%, and 80%) and three MAF levels (0%, 5%, and 10%) were considered and the five-fold cross validation was used to estimate the prediction accuracy. The results indicated that a moderate missing rate level (20% to 40%) and MAF (5%) threshold provided better prediction accuracy. Under this QC scenario, prediction accuracies were further calculated for imputed and GWAS-derived markers. It was observed that the accuracies of the six traits were related to their heritability and genetic architecture, as well as the GS prediction model. Moore–Penrose generalized inverse (GenInv), ridge regression (RidgeReg), and random forest (RForest) resulted in higher prediction accuracies than other GS models across traits. Imputation of missing genotypic data had marginal effect on prediction accuracy, while GWAS-derived markers improved the prediction accuracy in most cases. These results demonstrate that QC on missing rate and MAF had positive impact on the predictability of GS models. We failed to identify one single combination of QC scenarios that could outperform the others for all traits and GS models. However, the balance between marker number and marker quality is important for the deployment of GS in wheat breeding. GWAS is able to select markers which are mostly related to traits, and therefore can be used to improve the prediction accuracy of GS.

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Sasajima, Y., K. Sugaya, M. Ichimura, M. Imabayashi, and R. Yamamoto. "Atomic size effects on the stability of the 2D Penrose pattern." Journal of Physics: Condensed Matter 1, no. 45 (November 13, 1989): 8759–70. http://dx.doi.org/10.1088/0953-8984/1/45/001.

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Naumis, Gerardo G., Rafael A. Barrio, and Chumin Wang. "Effects of frustration and localization of states in the Penrose lattice." Physical Review B 50, no. 14 (October 1, 1994): 9834–42. http://dx.doi.org/10.1103/physrevb.50.9834.

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Foss, Ethan, and Christopher Winship. "Moore–Penrose Estimators of Age–Period–Cohort Effects: Their Interrelationship and Properties." Sociological Science 5 (2018): 304–34. http://dx.doi.org/10.15195/v5.a14.

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GARCKE, HARALD, ROBERT NÜRNBERG, and VANESSA STYLES. "Stress- and diffusion-induced interface motion: Modelling and numerical simulations." European Journal of Applied Mathematics 18, no. 6 (December 2007): 631–57. http://dx.doi.org/10.1017/s095679250700719x.

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We propose a phase field model for stress and diffusion-induced interface motion. This model, in particular, can be used to describe diffusion-induced grain boundary motion and generalizes a model of Cahn, Fife and Penrose as it more accurately incorporates stress effects. In this paper we will demonstrate that the model can also be used to describe other stress-driven interface motion. As an example, interface motion resulting from interactions of interfaces with dislocations is studied.

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Journal articles on the topic 'Penrose Effect'

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