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001-es BibID:	BIBFORM119313
035-os BibID:	(cikkazonosító)342 (WoS)000831829400001 (Scopus)85133190385
Első szerző:	Bagoly Zsolt
Cím:	The Spatial Distribution of Gamma-Ray Bursts with Measured Redshifts from 24 Years of Observation / Zsolt Bagoly, István Horvath, István I. Racz , Lajos G. Balázs, L. Viktor Tóth
Dátum:	2024
ISSN:	2218-1997
Megjegyzések:	: Gamma-ray bursts (GRBs) are the most luminous objects known: they outshine their host galaxies, making them ideal candidates for probing large-scale structure. Our aim is to determine the Spatial Two-Point Correlation Function of the GRBs with spectroscopic redshifts. We used all observations till 4 June 2021, and we also split the data according to the origin of the redshift (afterglow or host galaxy). We analyzed the possible correlation between the GRB redshift and sky position. There is only one region, called the Faraway GRB Patch, where nine distant GRBs shows deviation from the randomness with an ?1% significance, showing that the sky and the radial component of the GRB distribution could be factorized and both can be determined independently. The GRBs' cumulative monthly distribution was used to show that it is impossible to synthesize the Sky Exposure Function, even from the perfect observational logs. We estimated the Sky Exposure Function using the Gaussian kernel, and with the radial distribution, it was used for the estimation of the Spatial Two-Point Correlation Function. Monte Carlo simulations were used to determine the Poissonian errors. Our result shows that the current Spatial Two-Point Correlation Function estimations are consistent with zero for the full and the afterglow/host galaxy datasets.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk gamma-ray burst: general gamma-rays: general methods: data analysis methods: statistical cosmology: large-scale structure of the Universe cosmology: observations
Megjelenés:	Universe. - 8 : 7 (2022), p. 1-16. -
További szerzők:	Horváth István Rácz István (fizikus, csillagászat) Balázs Lajos G. Tóth Viktor
Pályázati támogatás:	K134257 OTKA
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM113610
035-os BibID:	(cikkazonosító)184 (Scopus)85153720827 (WoS)000981105300001
Első szerző:	Nagy Sándor (fizikus)
Cím:	Interpolation Formulas for Asymptotically Safe Cosmology / Sandor Nagy, Kornel Sailer
Dátum:	2023
ISSN:	2218-1997
Megjegyzések:	Simple interpolation formulas are proposed for the description of the renormalization group (RG) scale dependences of the gravitational couplings in the framework of the 2-parameters Einstein-Hilbert (EH) theory of gravity and applied to a simple, analytically solvable, spatially homogeneous and isotropic, spatially flat model universe. The analytical solution is found in two schemes incorporating different methods of the determination of the conversion rule k(t) of the RG scale k to the cosmological time t. In the case of the discussed model these schemes turn out to yield identical cosmological evolution. Explicit analytical formulas are found for the conversion rule k(t) as well as for the characteristic time scales tG and t? > tG corresponding to the dynamical energy scales kG and k?, respectively, arising form the RG analysis of the EH theory. It is shown that there exists a model-dependent time scale td (tG ? td < t?) at which the accelerating expansion changes to the decelerating one. It is shown that the evolution runs from a well-identified cosmological fixed point to another one. As a by-product we show that the entropy of the system decreases monotonically in the interval 0 < t ? t? due to the quantum effects.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk renormalization group
Megjelenés:	Universe. - 9 : 4 (2023), p. 1-22. -
További szerzők:	Sailer Kornél (1951-) (fizikus)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM106995
035-os BibID:	(Wos)000762026300001 (Scopus)85125085275
Első szerző:	Nagy Sándor (fizikus)
Cím:	Renormalizing Open Quantum Field Theories / Sandor Nagy, Janos Polonyi
Dátum:	2022
ISSN:	2218-1997
Megjegyzések:	The functional renormalization group flow of a scalar field theory with quartic couplings and a sharp spatial momentum cutoff is presented in four-dimensional Minkowski space-time for the bare action by retaining the entanglement of the IR and the UV particle modes. It is argued that the open interaction channels have to be taken into account in quantum field theory defined by the help of a cutoff, and a non-perturbative UV-IR entanglement is found in closed or almost closed models.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk renormalization group
Megjelenés:	Universe. - 8 : 2 (2022), p. 127-148. -
További szerzők:	Polónyi János
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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