Institute for Problems in Mechanics, Russian Academy of Sciences
Updated July 25, 2005
Classical model S_Dcl of the Dirac particle
S_D  is constructed. S_D 
is the dynamic system described by the Dirac
equation. For investigation of S_D 
and construction of  S_Dcl one uses a new dynamic method: dynamic
disquantization. This relativistic purely dynamic procedure does not use principles of quantum
mechanics. The obtained classical analog S_Dcl 
is described by a system of ordinary differential equations, containing the quantum constant
as a parameter. Dynamic equations for S_Dcl 
are determined by the Dirac equation uniquely. The dynamic system S_Dcl 
has ten degrees of freedom and cannot be a pointlike particle, because it has an
internal structure. Internal degrees of freedom appears to be described
nonrelativistically. One discusses interplay between the conventional axiomatic methods and the dynamical methods of the quantum systems
investigation. In particular, one discusses the reasons, why the internal degrees of freedom of the Dirac particle and their nonrelativistic character
were not discovered during eighty years.
There is text of the paper in
English and in Russian,