A redefinition of SI base units is scheduled to come into force on 20 May 2019. The kilogram, ampere, kelvin, and mole will then be defined by setting exact numerical values for the Planck constant (h), the elementary electric charge (e), the Boltzmann constant (k), and the Avogadro constant (NA), respectively. Read more wikipedia Nature 550, 313 (2017) PhysicsWorld — SI gets a makeover The…
ŠVK 2019
V sekcii Teoretická fyzika a astrofyzika v tomto roku súťažili: Róbert Kožurko (2.r. Fb) – Porovnanie presnosti vesmírnych a pozemských pozorovaní tranzitov exoplanét Matej Kecer (3.r. Fb) – Zmeny periód zákrytových dvojhviezd BD And a CL Aur Dominika Švecová (3.r. Fb) – Porovnanie “backward” a “forward” stochastických metód pre určenie modulácie kozmického žiarenia v heliosfére Maroš Jevočin (1.r. TFAm) – Teoretické štúdium vplyvu vápenatých iónov…
Black hole pictured for first time — in spectacular detail
Astronomers have finally glimpsed the blackness of a black hole. By stringing together a global network of radio telescopes, they have for the first time produced a picture of an event horizon — a black hole’s perilous edge — against a backdrop of swirling light. For more details see: https://www.nature.com/articles/d41586-019-01155-0 Image of a black hole at the centre of the galaxy M87 obtained by the…
Renormalization group analysis of stochastic and turbulent systems
In our works we apply quantum field methods developed initially to describe interactions between elementary particles to the problems of statistical physics, namely to the fully developed hydrodynamic turbulence. The general feature of such models of statistical physics like critical behaviour and turbulence is presence of strong fluctuations, and, therefore, the presence of divergences in perturbation theory and absence of small perturbation parameter. In this…