TY - JOUR TI - Measurable values, numbers and fundamental physical constants: Is the Boltzmann constant Kb a fundamental physical constant? AU - Bormashenko Edward AU - Sheshnev Avigdor JN - Thermal Science PY - 2009 VL - 13 IS - 4 SP - 253 EP - 258 PT - Article AB - The status of fundamental physical constants is discussed. The nature of fundamental physical constants is cleared up, based on the analysis of the Boltzmann constant. A new definition of measurable values, 'mathematical' and 'physical' numbers and fundamental physical constants is proposed. Mathematical numbers are defined as values insensitive to the choice of both units and frames of reference, whereas 'physical numbers' are dimensionless values, insensitive to transformations of units and sensitive to the transformations of the frames of reference. Fundamental constants are classified as values sensitive to transformations of the units and insensitive to transformations of the frames of reference. It is supposed that a fundamental physical constant necessarily allows diminishing the number of independent etalons in a system of units.