- Remarks on Clock Synchronization (1997) [Updated 1 decade ago]
- On the Connection Between Classical and Quantum Mechanics (1994) [Updated 1 decade ago]
- A Non-Einsteinian Equivalence Principle (1993) [Updated 6 years ago]

- Remarks on Clock Synchronization (1997) [Updated 1 decade ago]
Space-time coordinates, like any other physical quantity, should be given by their own operational definitions. This means that we should point out a physical process which can be used to measure them by comparison with standard phenomena defining the system of units. In particular, in order to be able to measure time at distant points in a unique way we must synchronize all clocks present in the system. The choice of synchronization method defines the model of space-time obtained and significantly influences its properties, physical as well as mathematical, including the structure of the space-time symmerty group [1,2].

- On the Connection Between Classical and Quantum Mechanics (1994) [Updated 1 decade ago]
In the hierarchy of physical theories classical Newton's mechanics may be considered as a "limit" of two more general theories: the relativistic classical mechanics and the non-relativistic quantum mechanics. In the first case, the limit is reached when in all relativistic formulae the velocity of light is going to infinity. The limiting procedure changes the shapes of formulae but does not change either the number of the physical interpretation of the corresponding quantities. In this sense we may say that we understand satisfactorily the limiting procedure both from the mathematical and physical point of view.

A similar conclusion is far to be true for the second case. All known ways of relating classical mechanics with "limits" of quantum mechanics suffer from the lack of precision. In particular, it is not known, either from mathematical or physical points of view, what is the classical limit of the most fundamental object of quantum mechanics - the wave function - when the Planck constant is going to zero.

- A Non-Einsteinian Equivalence Principle (1993) [Updated 6 years ago]
An equivalence principle valid not only for gravitation, but also for all fundamental interactions is proposed. It is shown that the new equivalence principle does not always coincide with the well-known Einstein equivalence principle.