Thermodynamics vs. Relativity

Faculty of Agriculture/Environment/Chemistry

Thermodynamics vs. Relativity

Thermodynamic research in recent years [1–5] revealed that the mass, time and space concepts of Albert Einstein's Theories of special and general relativity (SR and GR) [6–8] are incompatible with those of thermodynamics (TD).

While SR and GR state a relative time, with which all processes become symmetrical and completely reversible, the absolute time is a mandatory basis of the concept of a thermodynamic system and the description of irreversible processes. [Slide1] While modern physics assumes E = mc2 for the total energy E of a system [7], the 1st law of thermodynamics (the principle of the conservation of energy) is only compatible with E = mc2 + Epot. [Slide2]

E = mc2 + Epot  represents a new conceptual basis for the standard models of particle physics and cosmology. The non-ponderable energy amount Epot is the mechanical potential energy, i.e. the positional energy of system components and the system itself. For example, the internal energy U and thus E of a system change with its volume, interface area or spring tension. The mass of the system, by contrast, does not change at all, if substance and heat exchange are excluded. Volume, interface area, spring tension, position in the gravitational field etc. thus represent independent energetic properties of a body (matter) in addition to mass. In contrast to the so-called energy-mass equivalence  E = mc2 of SR, which describes a proportionality of the two state variables energy E and mass m, this was called energy-matter equivalence [2]:


Table 1. The mass concepts of special relativity (SR) and thermodynamics (TD).

  Energy-mass proportionality (SR) Energy-matter equivalence (TD)
Total measurable energy EE = mc2E = mc2 + Epot
Ponderable each kind of energy each kind of energy excluding mechanical potential energy
Rest mass m0 cannot be explained can be explained
Relativistic mass m(v) is disputed: real or apparent? is real
Matter concept Matter is reduced to mass. Matter is more than mass.

In a comprehensive analysis of theory and experiment, it was shown that the mass and time concepts of special relativity fail to describe reality, while those of thermodynamics are experimentally confirmed and can be applied in the micro- and macrocosm [5]. The application of thermodynamics at quantum level leads to a realistic understanding of elementary particles, their formation and development, i.e. to a realistic quantum thermodynamics. The essence of the thermodynamic approach is that matter is conceptually and energetically more than mass, and that time cannot be reduced to a relative pointer position of two clocks. The distinction between matter and mass and between time and concrete processes in material systems such as clocks suggests a new viewpoint on many open fundamental questions in physics.


  1. G. Kalies: Vom Energieinhalt ruhender Körper, De Gruyter, Berlin, 2019.
  2. G. Kalies: Matter-Energy Equivalence, Z. Phys. Chem. 234 (2020) 1567–1602.
  3. G. Kalies: A Solution of the Time Paradox of Physics, Z. Phys. Chem. (2020) 1–26.
  4. G. Kalies: A solution of the interpretation problem of Lorentz transformations (2020) 1–25. doi: 10.20944/preprints202007.0705.v1
  5. G. Kalies, C. Jooss: Contrasting mass and time concepts of special relativity and thermodynamics: The case for thermodynamics (2021), 1–24, arXiv: submit/3678824, on hold since several weeks.
  6. A. Einstein: Zur Elektrodynamik bewegter Körper, Ann. Phys. 322 (1905) 891–921.
  7. A. Einstein: Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig?, Ann. Phys. Chem. 18 (1905) 639–641.
  8. A. Einstein: Die Feldgleichungen der Gravitation, Sitzungsber. Königl. Preuß.Akad. Wiss. Berlin 2 (1915) 844–847.