Regularizacija rješenja za raspodjele nabijene prašine u Einstein–Maxwellovoj teoriji

Regularization of singular solutions for the static spherically symmetric extremelly charged dust in the Majumdar-Papapetrou system has been investigated. Singularities are of such a type that solutions become physically unacceptable since physically relevant quantities (metric invariants) are singular as well. With a simple redefinition of the charge/energy distributions, these solutions can be regularized. A spectrum of solutions with a number of zero-nodes in the metric tensor is found, and it is shown that their regularization can be accomplished either by using a d-shell, or a thick shell distribution of matter. The bifurcating behaviour of regular solutions is not present any more, but quantized-like behaviour in the total mass allocated to the solutions is observed.Istražujemo regularizaciju rješenja za statičku sferno simetričnu potpuno nabijenu prašinu u Majumdar-Papapetrouovom sistemu. Rješenja u njihovim koordinatama pokazuju singularnosti. Te su singularnosti takve naravi da su rješenja fizikalno neprihvatljiva jer su važne fizičke veličine (metričke invarijante) također singularne. Ta se rješenja mogu regularizirati jednostavnom promjenom definicije raspodjela naboja/energije. Našli smo spektar rješenja s nekoliko nul-čvorova u metričkom tenzoru, i pokazali da se može postići njihova regularizacija bilo s δ sferom, ili s debelom sfernom raspodjelom tvari. Nestaje grananje regularnih rješenja, ali se za ukupnu masu pridruženu rješenjima opaža ponašanje slično kvantizaciji

Regularizacija rješenja za raspodjele nabijene prašine u Einstein–Maxwellovoj teoriji

Regularization of singular solutions for the static spherically symmetric extremelly charged dust in the Majumdar-Papapetrou system has been investigated. Singularities are of such a type that solutions become physically unacceptable since physically relevant quantities (metric invariants) are singular as well. With a simple redefinition of the charge/energy distributions, these solutions can be regularized. A spectrum of solutions with a number of zero-nodes in the metric tensor is found, and it is shown that their regularization can be accomplished either by using a d-shell, or a thick shell distribution of matter. The bifurcating behaviour of regular solutions is not present any more, but quantized-like behaviour in the total mass allocated to the solutions is observed.Istražujemo regularizaciju rješenja za statičku sferno simetričnu potpuno nabijenu prašinu u Majumdar-Papapetrouovom sistemu. Rješenja u njihovim koordinatama pokazuju singularnosti. Te su singularnosti takve naravi da su rješenja fizikalno neprihvatljiva jer su važne fizičke veličine (metričke invarijante) također singularne. Ta se rješenja mogu regularizirati jednostavnom promjenom definicije raspodjela naboja/energije. Našli smo spektar rješenja s nekoliko nul-čvorova u metričkom tenzoru, i pokazali da se može postići njihova regularizacija bilo s δ sferom, ili s debelom sfernom raspodjelom tvari. Nestaje grananje regularnih rješenja, ali se za ukupnu masu pridruženu rješenjima opaža ponašanje slično kvantizaciji

Praznična glasba kapitljev na Krku in njena recepcija pri srednješolcih

Disertacija Praznična glasba kapitljev na Krku in njena recepcija pri srednješolcih preučuje odnos mladih srednješolcev (od štirinajstega do osemnajstega leta) z otoka Krka do tradicijske glasbe otoka Krka v kontekstu praznovanja svet­nikov zavetnikov krajev v cerkvenih enotah, imenovanih kapitlji

Separation techniques for disentangling of composite spectra

Disentangling of composite spectra is a promissing technique for the analysis of double-lined spectroscopic binary systems. The technique makes use of a separation routine to extract model-component spectra out of a time series of observed composite spectra. Focusing on the differences between two possible approaches in the implementation of the separation routine, we compare the resulting limitations. We perform test runs on artificial data and conclude that separation in the wavelength domain is more versatile in several aspects, while the computational efficiency of separation in the Fourier domain allows working with larger data sets which is beneficial in a fully-blown disentangling process

Tehnike razdvajanja za raspetljavanje složenih spektara

Disentangling of composite spectra is a promissing technique for the analysis of double-lined spectroscopic binary systems. The technique makes use of a separation routine to extract model-component spectra out of a time series of observed composite spectra. Focusing on the differences between two possible approaches in the implementation of the separation routine, we compare the resulting limitations. We perform test runs on artificial data and conclude that separation in the wavelength domain is more versatile in several aspects, while the computational efficiency of separation in the Fourier domain allows working with larger data sets which is beneficial in a fully-blown disentangling process.Raspetljavanje složenih spektara je obećavajuća metoda za proučavanje dvojnih zvjezdanih sustava. Ta metoda primjenjuje rutinu za razdvajanje kojom se izlučuje spektre zvijezda komponenata modela iz vremenskog niza opaženih složenih spektara. Usredotočujući se na razlike u pristupu pri izvedbi rutine za rastavljanje, uspoređujemo ograničenja koja iz njih proizlaze. Proveli smo ispitivanje s umjetnim podacima i zaključili da je rastavljanje u području valnih duljina svestranije u više pogleda, dok rastavljanje primjenom Fourierovog transformata dozvoljava rad s većim skupovima podataka, što je povoljno u potpunom procesu raspetljavanja složenih spektara

Tehnike razdvajanja za raspetljavanje složenih spektara

Disentangling of composite spectra is a promissing technique for the analysis of double-lined spectroscopic binary systems. The technique makes use of a separation routine to extract model-component spectra out of a time series of observed composite spectra. Focusing on the differences between two possible approaches in the implementation of the separation routine, we compare the resulting limitations. We perform test runs on artificial data and conclude that separation in the wavelength domain is more versatile in several aspects, while the computational efficiency of separation in the Fourier domain allows working with larger data sets which is beneficial in a fully-blown disentangling process.Raspetljavanje složenih spektara je obećavajuća metoda za proučavanje dvojnih zvjezdanih sustava. Ta metoda primjenjuje rutinu za razdvajanje kojom se izlučuje spektre zvijezda komponenata modela iz vremenskog niza opaženih složenih spektara. Usredotočujući se na razlike u pristupu pri izvedbi rutine za rastavljanje, uspoređujemo ograničenja koja iz njih proizlaze. Proveli smo ispitivanje s umjetnim podacima i zaključili da je rastavljanje u području valnih duljina svestranije u više pogleda, dok rastavljanje primjenom Fourierovog transformata dozvoljava rad s većim skupovima podataka, što je povoljno u potpunom procesu raspetljavanja složenih spektara

Separation techniques for disentangling of composite spectra

Disentangling of composite spectra is a promissing technique for the analysis of double-lined spectroscopic binary systems. The technique makes use of a separation routine to extract model-component spectra out of a time series of observed composite spectra. Focusing on the differences between two possible approaches in the implementation of the separation routine, we compare the resulting limitations. We perform test runs on artificial data and conclude that separation in the wavelength domain is more versatile in several aspects, while the computational efficiency of separation in the Fourier domain allows working with larger data sets which is beneficial in a fully-blown disentangling process

Canonical active Brownian motion

Active Brownian motion is the complex motion of active Brownian particles. They are active in the sense that they can transform their internal energy into energy of motion and thus create complex motion patterns. Theories of active Brownian motion so far imposed couplings between the internal energy and the kinetic energy of the system. We investigate how this idea can be naturally taken further to include also couplings to the potential energy, which finally leads to a general theory of canonical dissipative systems. Explicit analytical and numerical studies are done for the motion of one particle in harmonic external potentials. Apart from stationary solutions, we study non-equilibrium dynamics and show the existence of various bifurcation phenomena.Comment: 11 pages, 6 figures, a few remarks and references adde

Regular and quasi black hole solutions for spherically symmetric charged dust distributions in the Einstein-Maxwell theory

Static spherically symmetric distributions of electrically counterpoised dust (ECD) are used to construct solutions to Einstein-Maxwell equations in Majumdar--Papapetrou formalism. Unexpected bifurcating behaviour of solutions with regard to source strength is found for localized, as well as for the delta-function ECD distributions. Unified treatment of general ECD distributions is accomplished and it is shown that for certain source strengths one class of regular solutions approaches Minkowski spacetime, while the other comes arbitrarily close to black hole solutions.Comment: LaTeX (IOP style) 17 pages, 10 figure