GRAVITATIONAL MICROLENSING BY THE ELLIS WORMHOLE
نویسندگان
چکیده
منابع مشابه
The Ellis wormhole with ‘ tachyon matter ’
The Ellis wormhole is known to be an exact solution of the Einstein–scalar system where the scalar field has negative kinetic energy (phantom). We show here that the same geometry (in 3+1 dimensions) can also be obtained with ‘tachyon matter’ as a source term in the field equations and a positive cosmological constant. The kink–like tachyon field profile and the nature of the tachyon potential ...
متن کاملGravitational Microlensing by the Globular Cluster Stars
The microlensing of background stars by compact objects in globular clusters is analyzed. The main strength of the proposed search is the direct relationship between the lens mass and the time scale of the microlensing event. The main problem is the low overall rate of expected events which implies that a ground based search should last for about a decade to generate a non trivial number of eve...
متن کاملMeasuring Stellar Limb Darkening by Gravitational Microlensing
Observations of microlensing transit events can be used to measure the limb darkening of the lensed star. We discuss the advantages and drawbacks of several microlensing light curve inversion methods. The method of choice in this work is inversion by means of decomposition of the stellar surface brightness profile. We construct an ideal basis by principal component analysis of brightness profil...
متن کاملDetecting Stellar Spots by Gravitational Microlensing
During microlensing events with a small impact parameter the amplification of the source flux is sensitive to the surface brightness distribution of the source star. Such events provide a means for studying the surface structure of target stars in the ongoing microlensing surveys, most efficiently for giants in the Galactic Bulge. In this work we demonstrate the sensitivity of point-mass microl...
متن کاملIntroduction to Gravitational Microlensing
The basic concepts of gravitational microlensing are introduced. We start with the lens equation, and then derive the image positions and magnifications. The statistical quantities of optical depth and event rate are then described. We finish with a summary and a list of challenges and open questions. A problem set is given for students to practice. Gravitational microlensing (in the local grou...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2010
ISSN: 0004-637X,1538-4357
DOI: 10.1088/0004-637x/725/1/787