Seminar for Geometry, education and visualization with applications
PROGRAM
MATEMATIČKI INSTITUT SANU
Seminar geometriju, obrazovanje i vizualizaciju sa primenama
PLAN RADA ZA MART 2017.
ČETVRTAK, 09.03.2017. u 17:15, sala 301f, MI
Ivan Dimitrijević, Matematički Fakultet, Beograd
GEOMETRIJSKA GENERALIZACIJA AJNSTAJNOVE TEORIJE GRAVITACIJE
Ajnstajnova teorija gravitacije uspesno opisuje pojave u
Suncevom sistemu. Ona takodje predvidja postojanje crnih rupa,
gravitacionih sociva i gravitacionih talasa, sto je uspesno
opservirano. Medjutim Ajnstajnova teorija nije dovoljno proverena na
velikim kosmickim rastojanjima. Zbog toga, posmatramo nelokalnu
modifikaciju gravitacije i dobijamo nova resenja za skalirajuci faktor
a(
t). Takodje, posmatramo i prostorno-vremenske perturbacije oko de
Siterovog prostora.
ČETVRTAK, 16.03.2017. u 17:15, sala 301f, MI
Batat Wafaa
ON THE CLASSIFICATION OF HOMOGENEOUS LORENTZIAN STRUCTURES
The complete classification of the simply connected three-dimensional
naturally reductive Riemannian manifolds was given by Tricerri and
Vanhecke (1983). In this talk, we shall generalize this result to the
Lorentzian case. We obtain, as in the Riemannian case, the symmetric
spaces and further the unimodular Lie groups SU(2), SL(2,R) and the
Heisenberg group equipped with some left-invariant Lorentzian metric.
On the other hand, we shall classify all homogeneous Lorentzian structures
on some Lorentzian manifolds such as Egorov spaces, three-dimensional
manifolds admitting a parallel null vector field and the Heisenberg group.
ČETVRTAK, 23.03.2017. u 17:15, sala 301f, MI
Batat Wafaa
ON THE CLASSIFICATION OF HOMOGENEOUS LORENTZIAN STRUCTURES
The complete classification of the simply connected three-dimensional
naturally reductive Riemannian manifolds was given by Tricerri and
Vanhecke (1983). In this talk, we shall generalize this result to the
Lorentzian case. We obtain, as in the Riemannian case, the symmetric
spaces and further the unimodular Lie groups SU(2), SL(2,R) and the
Heisenberg group equipped with some left-invariant Lorentzian metric.
On the other hand, we shall classify all homogeneous Lorentzian structures
on some Lorentzian manifolds such as Egorov spaces, three-dimensional
manifolds admitting a parallel null vector field and the Heisenberg group.
ČETVRTAK, 30.03.2017. u 17:15, sala 301f, MI
Miloš Djorić, Matematički Fakultet
OSOBINE BLIZU KELEROVE MNOGOSTRUKOSTI $S^3 \times S^3$
Pokazacemo kako se metrika, skoro kommpleksna i skoro produkt struktura
homogene blizu Kelerove mnogostrukosti $S^3 \times S^3$ mogu dobiti pomocu
submerzije $\phi: S^3 \times S^3 \times S^3 \to S^3 \times S^3$.
Preslikavanja na $S^3 \times S^3 \times S^3$ dobijena permutovanjem dve
koordinate ili ciklicnim pomeranjem koordinata slazu se sa submerzijom.
Pokazacemo koja preslikavanja ona indukuju na $S^3 \times S^3$ i kako se
slazu sa skoro kompleksnom i skoro produkt strukturom.
Predstavitiću rezultate koje su dobili kolege Luc Vrancken i Marilena Moruz.
Sednice seminara odrzavaju se u zgradi Matematickog instituta SANU, Knez Mihailova 36, na trecem spratu u sali 301f.
Rukovodilac Seminara dr Stana Nikcevic