critical amplitude B$_{0}$ for the order parameter of the LJ liquid: with that of the Ising model: Taking into account the relation (8) between temperature variables T and t via compar- ison (36) and (37) we obtain the following relation between amplitudes As the amplitude B ( Is ) 0 is known form exact result at D = 2 or from computer simulation for D = 3 (see e.g. [29]) one get the critical amplitude for LJ fluid. For the real 3 D fluids this gives B ( LJ ) 0 ≈ 1 . 69 for 2 D case and B ( LJ ) 0 ≈ 1 . 85 for 3 D case. Then the proximity of the numerical values of the critical exponents for the systems of the Ising model universality class to the rational numbers is quite natural. They do not necessary close to the mean- field values of the Landau theory and for the systems with the short-range interactions the mean-field behavior is not observed far away from the CP [30]. This gives the grounds for the universal global cubic law for the binodal proposed in [14]. In essential, the same global cubic law is widely used in computer simulations of the system with short ranged interactions [29, 31]. The fluctuations renormalize these rational exponents near the CP through small exponents η and α , which determine the behavior of the correlation functions of the density and the entropy in the immediate vicinity of the CP [32]. The fluctuations are responsible for the deviation from the linear diameter law (2). If we assume that the transformations between thermodynamic averages like x and n are generated by the trans- formations between the corresponding microscopic fields then such deviation is interpreted as the consequence of the nonlinearity of the transformation for the field variables. Indeed for the nonlinear functional F of the thermodynamic field n ( r ) in the presence of strong fluctuations 〈 F [ n ( r )] 〉 = F ( 〈 n ( r ) 〉 ), where 〈 . . . 〉 denotes the statistical average. From this point of view the transformation (8) can be considered as the “mean-field“ analog of commonly used linear mixing of the fields in the vicinity of the CP [8, 33]. 12 n − n$_{c}$ n$_{c}$ = ± B (LJ) 0 | τ | β + . . . , (36) 2 x − 1 = ± B (Is) 0 | τ | β + . . . . (37) B ( LJ ) 0 ≈ B ( Is ) 0 ( 1 + z ) β .