Time and place:
21.02.2020 г., 18:00; New Bulgarian University, Hall 205, Building 1
Dr. Bogdan G. Dimitrov – Institute of Nuclear Research and Nuclear Energetics of the Bulgarian Academy of Sciences and Institute for Advanced Physical Studies, New Bulgarian University
A general knowledge about the fundamental physical principles of the Global Positioning System (GPS) will be presented. One of these principles is related to the fundamental (experimentally proved – the Michelson-Morley experiment) fact about the independence of the velocity of light from the velocity of the source of light and the non-existence of the “ether”, which is the starting point for the creation of the Special Theory of Relativity by Albert Einstein. Particular attention will be paid to some (elementary) model examples, which result in important relations, concerning the frequency change of the signal between the stations on the Earth’s surface and the rotating around the Earth satellites, which depends on the rotation of the Earth as well as on the variation of the gravitational potential. The amazing relation of these dependences to the approach of Special Theory of Relativity will be demonstrated, also the further extension of the approach in the framework of the General Theory of Relativity, which is being applied in the theory of the Global Positioning System since 2003. The Geocentric Relativistic Reference System will be briefly reviewed and the determination of the atomic clock times with respect to an attached to the Earth rotating coordinate system, which is important for taking into account of the General Relativity Theory effects for the satellite motion in the near-Earth space.
This lecture will take place within the seminar “Cosmology, gravitation and astrophysics”, organized by the Institute for Advanced Physical Studies