SYMMETRY-THERMODYNAMICS CONCEPTION Yu. M. Smirnov Tver State University, 170000 Tver, Russia

The symmetry-thermodynamics conception includes symmetry analysis of thermodynamical forces and flows in both isotropic and anisotropic objects, general superposition principle of the physical properties of objects and physical fields on the basis of Curie principle, and the rule of resulting symmetry group determination in interacting systems [1].

We have studied the following interactions of thermodynamic forces and flows: scalar - axial vector - polar tensor (even rank quantities); pseudoscalar - polar vector - even rank pseudotensor. Provided a general parameter N is used to describe the tensor rank of a physical quantity having its axiality characterized by 1 or 0, the transition from general to particular for the above mentioned quantities will be as follows: 0+0; 1+1; 2+0; 0+1; 1+0; 2+1. Consider as an example the following equations [2]:

where and rT are entropy, electric induction, magnetic induction, deformation, magnetic field intensity, electric field intensity and tensor of stresses, respectively, while q, v, b and u are vectors or tensors of pyromagnetic, magnetoelectric, piezomagnetic effects and magnetic permeability tensor, respectively.

In these and similar cases the traditional tensor classification by magnetic (q, b), even (u) and magnetoelectric ([[nu]]) ones appears to be unnecessary, because it is sufficient to make use of characteristics (types) of evenness and oddness. With this provision q, [[nu]], [[nu]], u, b, b tensors are fully defined by (1+1), (2+1), (2+1), (2+0), (3+1), (3+1) values being classified solely as even quantities - q, b, u and odd quantities - [[nu]]. The Curie symmetry groups for these quantities are -[[infinity]]/m, ([[infinity]]/m)mm and [[infinity]]22, respectively (in other cases subgroups with lower symmetry are possible). However the existence of l inversion is a necessary condition for even group quantities as well as its absence for odd ones.

[1] Yu. M. Smirnov, Physics of Crystallization (Kalinin, KSU, 1990).

[2] Yu. I. Sirotin, M. P. Shaskolkaya, Foundations of Crystal Physics (Moscow, 1970).