gott-kaiser-stebbins (gks) effect in an accelerated expanding universe

Authors

s. y. rokni

h. razmi

m. r. bordbar

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 astrophysics

Publisher: damghan university astronomical society of iran

ISSN ‪۲۳۲۲-۴۹۲۴

volume 2

issue 2 2015

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