14672

13213

كارشناسي ارشد

فيزيك ذرات بنيادي

اصفهان : دانشگاه صنعتي اصفهان

1397

نه، 52ص. : مصور

فرهنگ لران

بهروز ميرزا

صديقه سجاديان، غلامرضا خسروي

1398/03/20

كتابنامه

فيزيك

فيزيك

1398/03/20

2540613

Classical scalar and vector fields in static wormholes Bahareh Azad b azad@ph iut ac ir March 12 2019 Department of Physics Isfahan University of Technology Isfahan 84156 83111 Iran University Code IUT 77142 Degree M Sc Language Farsi supervisor Prof Farhang Loran loran@cc iut ac ir Abstract Wormholes are bridges connecting two regions of spacetime These regions may be consid ered in a universe or two different universes These geometries are solutions to the equationsof gravitational theories such as Einstein s general relativity In this thesis we examine the behavior of the classical scalar and Maxwell fields in thebackground of static and spherically symmetric wormholes and show that certain geometricproperties of such wormholes can be studied by examining the asymptotic behavior of thefields We show that the scalar field equation can be analyzed by using the spherical symmetryand the method of separation of variables to separate the contribution of the angular mo mentum term and converting the radial equation to the Schr dinger equation reducing it tothe scattering problem in one dimensional quantum mechanics and calculating the potentialfunction corresponding to every wormhole This potential function in addition to a generalcontribution from the angular momentum also depends on the peculiarities of the geometry By calculating the scattering matrix we obtain the transmission and reflection amplitudesfor the scalar field scattered by the wormhole For classical Maxwell fields by extending the concepts of electric and magnetic fields fromMinkowski spacetime to the wormhole spacetime we show that the optical characteristics ofwormholes can be simulated by interpreting the curvature effects of the spacetime in termsof the permittivity and permeability of a certain optical medium in the flat spacetime Giventhe asymptotic behavior of this geometry which is similar to the flat spacetime we writethe solution in terms of the multipole expansion and show that the correct variable of thisseries is not the ordinary radial coordinate but a definite function thereof We show thatthis specific change of variable actually represents the symmetry of the Maxwell equationsunder the conformal transformations of the metric Since the Maxwell action is invariantunder the conformal transformations of the spacetime metric instead of solving the Maxwellequations in some given geometry we can search for a solution in a simpler geometry obtainedby conformal transformation We approve the former results in this way Keywords wormholes classical scalar field classical Maxwell field scattering in curvedspacetime

فرهنگ لران

بهروز ميرزا

صديقه سجاديان، غلامرضا خسروي