Yiannis Contoyiannis
University of the West
Particle physicsQuantum chromodynamicsPhysicsStatistical physicsCriticalitySpontaneous symmetry breakingGeologyCritical point (thermodynamics)Phase transitionCritical exponentSeismologyField (physics)Critical phenomenaSymmetry breakingCondensed matter physicsIntermittencyMathematicsFracture (geology)Ising modelRenormalization groupGeophysicsPower law
68Publications
19H-index
706Citations
Publications 67
Newest
#1Yiannis Contoyiannis (UWest: University of the West)H-Index: 19
#2Stelios M. Potirakis (UWest: University of the West)H-Index: 17
Last. Efstratios K. Kosmidis (A.U.Th.: Aristotle University of Thessaloniki)H-Index: 15
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Abstract Combining concepts of artificial neural networks (ANNs) with the stochastic dynamics of Ising spin lattices we introduce a hybrid model, the hybrid spin model (HSM). We find that the HSM carries the critical/tricritical fluctuations of the 2D Ising model and allows for an accurate estimation of the isothermal critical/tricritical exponents of 2D Ising universality class. Our work clearly demonstrates that HSM launches a new category of models supporting alternative pathways for the real...
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#2M. P. HaniasH-Index: 14
Last. Georgios BalasisH-Index: 21
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This paper presents our study of the presence of the unstable critical point in spontaneous symmetry breaking (SSB) in the framework of Ginzburg–Landau (G-L) free energy. Through a 3D Ising spin lattice simulation, we found a zone of hysteresis where the unstable critical point continued to exist, despite the system having entered the broken symmetry phase. Within the hysteresis zone, the presence of the kink–antikink SSB solitons expands and, therefore, these can be observed. In scalar field th...
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#1Dimitrios Z. Politis (UWest: University of the West)
#2Stelios M. Potirakis (UWest: University of the West)H-Index: 17
Last. Masashi Hayakawa (University of Electro-Communications)H-Index: 69
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In this work we present the statistical and criticality analysis of the very low frequency (VLF) sub-ionospheric propagation data recorded by a VLF/LF radio receiver which has recently been established at the University of West Attica in Athens (Greece). We investigate a very recent, strong (M6.9), and shallow earthquake (EQ) that occurred on 30 October 2020, very close to the northern coast of the island of Samos (Greece). We focus on the reception data from two VLF transmitters, located in Tur...
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#1Fotis K. Diakonos (UoA: National and Kapodistrian University of Athens)H-Index: 26
Last. Stelios M. PotirakisH-Index: 17
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We show that the spontaneous symmetry breaking can be defined also for finite systems based on the properly defined jump probability between the ground states in the 2d and 3d Ising models on a square and a cubic lattice respectively. Our analysis reveals the existence of an interval in the temperature (control parameter) space within which the spontaneous symmetry breaking takes place. The upper limit of this region is the pseudocritical point where the symmetric vacuum bifurcates in energetica...
In this brief, the spontaneous symmetry breaking (SSB) of the \varphi^4theory in phase space, is studied. This phase space results from the appropriate system of Poincare maps, produced in both the Minkowski and the Euclidean time. The importance of discretization in the creation of phase space, is highlighted. A series of interesting, novel, unknown behaviors are reported for the first time; among them the most characteristic is the change in stability. In specific, the stable fixed points o...
1 CitationsSource
Last. Constantinos NomicosH-Index: 21
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It has recently been found that the evolution of the preparation of a strong earthquake (EQ), as it is monitored through fracture-induced electromagnetic emissions (EME) in the MHz band, presents striking similarity with the evolution of a thermal system as temperature drops, since distinct steps of the evolution of the phenomenon of spontaneous symmetry breaking (SSB) can be identified. Here, the study of fracture-induced EME in the MHz band in analogy to thermal systems is extended to the phas...
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#1Yiannis Contoyiannis (UWest: University of the West)H-Index: 19
#2Stavros G. Stavrinides (International Hellenic University)H-Index: 10
Last. E. K. Kosmidis (A.U.Th.: Aristotle University of Thessaloniki)
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Recently, it has been successfully shown that the temporal evolution of the fraction of COVID-19 infected people possesses the same dynamics as the ones demonstrated by a self-organizing diffusion model over a lattice, in the frame of universality. In this brief, the relevant emerging dynamics are further investigated. Evidence that this nonlinear model demonstrates critical dynamics is scrutinized within the frame of the physics of critical phenomena. Additionally, the concept of criticality ov...
2 CitationsSource
#1Yiannis Contoyiannis (UoA: National and Kapodistrian University of Athens)H-Index: 19
Last. Myron KampitakisH-Index: 2
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A device consisting of an array of coaxial, identical, circular rings behaves like a solenoid when the ratio of its radius and distance between two successive rings is higher than 1. As this ratio decreases, the device significantly deviates from the solenoid behavior. At the same time, a diffraction-like phenomenon for the magnetic field appears when currents of random direction flow through the rings. This phenomenon demonstrates critical behavior. Thus, an extension of the diffraction phenome...
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#1Yiannis Contoyiannis (UWest: University of the West)H-Index: 19
#2Pericles Papadopoulos (UWest: University of the West)H-Index: 1
Last. N. L. Matiadou (UWest: University of the West)
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We express the Kirchhoff wave equation in terms of classic field theory. This permits us to introduce the spontaneous symmetry breaking phenomenon in the study of linear structures, such as strings in order to investigate the existence of solitons solutions. We find ϕ4 solitons in the space of spatial gradient of lateral displacement of a string. This helps us detect stable states in deformations of strings.
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