6 March (Friday) 4:15 PM  Room 224
György Szondy*
What is Time? Why is General Relativity Nonlinear?
According to theoretical physicists (relativists) time (= proper-time) is what the atomic clock shows ... but it is also well known that “clocks in strong gravity tick slower than clocks in weak gravity”. It means that the dτ/dt depends on the position, more precisely the altitude of the actual clock.

Then what the Time really is? How do we measure it? What is the role of different time measures?

Engineers and relativists have different concepts of time. As a result, satellite navigation (GPS) computing needs are orders of magnitude lower than General Relativity. Still, GPS works well, and what’s more: the two approaches are equivalent.

Balloon Relativity is a simple model that helps to understand why the description of engineers and Einstein is equivalent, and how nonlinearity, locality, and other properties of General Relativity (e.g. gravitational redshift or Shapiro time-delay) caused by its definitions.

* György Szondy graduated as an electrical engineer at BME in 1995. Since 2000 he has been dealing with the fundamental questions of General Relativity and its alternatives: scalar-tensor gravity, quantum gravity as well as Satellite Navigation (GPS). He has several publications on the subject. As an independent researcher, together with Wigner and BME researchers he takes part in the high precision re-measurement of the Eötvös equivalence principle (EPF experiment).

27 March (Friday) 4:15 PM  ONLINE:

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Tamás Geszti
Department of Physics of Complex Systems, Institute of Physics
Eötvös University, Budapest
The Law and its properties

Laws of Nature make up interesting logical structures. The most widespread kind of it is a nested sequence of more and more refined descriptions of the same phenomenon, the older version being a property of the later one. Important examples are: Newton’s mechanics as a property of Schrödinger’s equation of quantum mechanics; or electric circuit laws as a property of Maxwell’s equations. A currently interesting example is the active field of research called Foundations of Quantum Mechanics; there it is an open question whether randomness and Born’s law are parts of the law as we use it, or properties of some still unknown law of nature.

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Tamás Geszti -- our first online seminar session during the Covid-19 closing