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Research Center for Quantum Information
Institute of Physics, Slovak Academy of Sciences
Dúbravská cesta 9, 84511 Bratislava, Slovakia
Tel: (+421 +2) 20910701
Fax: (+421 +2) 5477-6085
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N E W S | old news |
  14.1.2015 Lectures
The firewall paradox from the general relativity theory perspective
The series of lectures will be given by Martin Scholtz from Faculty of Mathematics and Physics of Charles Univsersity in Prague. Lectures plan (in Slovak):
  1. Repetitórium všeobecnej relativity - Variety, vektorové a tenzorové polia, konexia a krivosť. Einsteinov tenzor, Einsteinove rovnice. Vybrané presné riešenia: Schwarzschildova a Kerrova čierna diera, kozmologické modely.
  2. Kauzálna a konformná štruktúra priestoročasu - Asymptoticky ploché priestoročasy, Penroseove diragramy, Kruskalovo rozšírenie Schwarzschildovho riešenia, konformný diagram kolabujúcej hviezdy. Definícia čiernej diery. Penroseove-Hawkingove teorémy o singularitách.
  3. Termodynamika čiernych dier - Povrchová gravitácia a nultý zákon termodynamiky pre čierne diery. Entropia čiernej diery a druhý zákon termodynamiky.Kvázilokálna definícia horizontu: izolované a dynamické horizonty.
  4. Kvantová teória poľa na krivom pozadí Rindlerov priestoročas a blízkohorizontová geometria. Bogoljubovova transformácia, Unruhov efekt, Hawkingov efekt a vyparovanie čiernych dier. Populárne rozprávanie o informačnom paradoxe, "black hole complementarity", náznak firewall paradoxu, plodná diskusia.
Place: seminar room of our research center
Time: 2-5.2.2015 (Monday-Thursday), 10:30-12:30.
  15.2.2015 Research publication
Thermodynamic model of social influence on two-dimensional square lattice: Case for two features
We propose a thermodynamic multi-state spin model in order to describe equilibrial behavior of a society. Our model is inspired by the Axelrod model used in social network studies. In the framework of the statistical mechanics language, we analyze phase transitions of our model, in which the spin interaction J is interpreted as a mutual communication among individuals forming a society. The thermal fluctuations introduce a noise T into the communication, which suppresses long-range correlations. Below a certain phase transition point Tt, large-scale clusters of the individuals, who share a specific dominant property, are formed. The measure of the cluster sizes is an order parameter after spontaneous symmetry breaking. By means of the Corner transfer matrix renormalization group algorithm, we treat our model in the thermodynamic limit and classify the phase transitions with respect to inherent degrees of freedom. Each individual is chosen to possess two independent features f and each feature can assume one of q traits (e.g. interests). Hence, each individual is described by q2 degrees of freedom. A single first-order phase transition is detected in our model if q>2, whereas two distinct continuous phase transitions are found if q=2 only. Evaluating the free energy, order parameters, specific heat, and the entanglement von Neumann entropy, we classify the phase transitions Tt(q) in detail. The permanent existence of the ordered phase (the large-scale cluster formation with a non-zero order parameter) is conjectured below a non-zero transition point Tt(q)=0.5 in the asymptotic regime of infinite q.
by Jozef Genzor, Vladimír Bužek, Andrej Gendiar
Physica A 420, 200-211 (2015) [arXiv:1403.1771] |+++|
QIMABOS (APVV-0808-12) DARG (VEGA-2/0074/12), SIQS (No.600645)
S E M I N A R S | more |
24/04 13:00
Jozef Genzor (Bratislava)
Introduction to subriemannian geometry
V I S I T O R S | history |

16.04-17.04 Vedran Dunjko
(University of Innsbruck, Austria)

16.04-17.04 Nicolai Friis
(University of Innsbruck, Austria)

14.06-21.06 Alexander S. Kholevo
(Stekhlov Institute, Moscow, Russia)

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