Secondary
Differential Calculus and "Quantum Differential
Calculus"
In some sense diffieties are smooth manifolds with possible
singularities and usually they have infinite
dimension. This last fact does not allow to
develop on these objects a reasonable Differential Calculus
by using the traditional methods of Analysis and classical
Differential Geometry. Yet such difficulties are easily
overcome by using the algebraic approach to Differential
Calculus—the aforementioned Primary Differential Calculus.
Thus Primary Differential Calculus becomes the
indispensable basis for building a consistent reasonable
differential calculus on diffieties. That part of
the Primary Calculus on diffieties which in some sense is
respectful of the natural geometrical structures on
diffiety is called Secondary Differential
Calculus. Traditional theory of varieties—both
smooth and algebraic—appears in the theory of diffieties as
its 0-dimensional case. This means that the Secondary
Calculus respects the mathematical correspondence
principle. In other words, the traditional differential
mathematics can be interpreted as the limit case when the
diffiety-dimension goes to 0. [...]
The mathematical correspondence principle concretized in
this way shows that any natural concept of the Differential
Calculus of Classical Differential Geometry admits an
analogue in Secondary Calculus. Therefore the
general mathematical analogue of the quantization problem
becomes the secondarization problem—the
"mathematical quantization". In other words, the latter is
the problem of constructing the analogues in Secondary
Calculus of all the concepts and natural operations of all
the traditional "differential mathematics". The
secondarization problem being more general and thus more
transparent than the quatization problem in Physics admits
an exact formalization which will be discussed later on.
Presently the state of the art is such that in any concrete
case the secondarization problem is an algorithmic problem,
which does not mean that the realization of the
corresponding algorithm is easy and immediate, but it is
important to stress that this is not a problem of
principle. Now the complete solution to the
secondarization problem for the basis components of the
classical fields theory is just a question of time. Due to
the huge dimensions of the finishing works, consistent
human resources are needed for it, but it is already
possible to clearly foresee that the quantum fields theory
will become in a not so distant future the study of some
secondary differential equations. Still now some
touching point of Secondary Calculus with some
branches of contemporary Theoretical Physics like
BRST transform and anti-field formalism, can be found.
These two chapters of Physics—sometimes referred to as
Cohomological Physics—can be described in the language of
Secondary Calculus in a natural and conceptually clear way,
in spite of the fact that the latter has been developed in
an absolutely independent way from any problem of
Theoretical Physics.