Gott-Kaiser-Stebbins (GKS) effect in an accelerated expanding universe

Authors

H. Razmi Department of Physics, University of Qom, Qom, I. R. Iran;

M. R. Bordbar Department of Physics, University of Qom, Qom, I. R. Iran;

S. Y. Rokni Department of Physics, University of Qom, Qom, I. R. Iran;

Abstract:

Wewanttoﬁndthecosmologicalconstantinﬂuenceoncosmicmicrowavebackground(CMB)temperatureduetomovinglinearcosmicstrings.Usingthespace-timemetricofalinearcosmicstringinanacceleratedexpandinguniverse,theGott-Kaiser Stebbins(GKS)eﬀect,asanimportantmechanisminproducingtemperaturediscontinuityinthe(CMB),isconsidered;then,itsmodiﬁcationduetotheeﬀectofthecosmologicalconstantiscalculated.Theresultshowsthatapositivecosmologicalconstant(i.e.thepresenceofcosmicstringsinanacceleratedexpandinguniverse)weakensthediscontinuityintemperaturesothatastrongerresolutionisneededtodetectthecorrespondinginﬂuencesontheCMBpowerspectrumandanisotropy.

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Journal title

Iranian Journal of Astronomy and Astrophysic

volume 2 issue 2

pages 121- 125

publication date 2015-12-01

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Keywords

ISM: Cosmic Strings Cosmological Constant Cosmic Microwave Background (CMB)

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