thermodynamics.
This publication is structured as follows : the structure of the relativistic con-
tinuity equations for scalar and vector quantities is established in Sec. 2 by
following the approach outlined by St¨uckelberg. [18] The relativistic statements
of the second and first law are presented in Sec. 3 and 4 together with the rela-
tivistic continuity equations for the entropy and energy-momentum. In Sec. 5,
we establish the relativistic continuity equation for the orbital angular momen-
tum, which implies the symmetry of the stress-energy-momentum tensor. The
relativistic matter continuity equation is derived in Sec. 6. As a prelude to the
study of the dynamics and thermodynamics of a perfect fluid, we first examine
the dynamics of a relativistic dust in Sec. 7 and derive the corresponding stress-
energy-momentum tensor in Sec. 8. Taking into account the pressure and the
internal energy density, we generalise our analysis to the study of the dynamics
of a perfect fluid in Sec. 9 and derive the corresponding stress-energy-momentum
tensor in Sec. 10. This leads to the introduction of a relativistic inertia density
that differs from the mass density. Using the thermodynamic definition of the
temperature, the pressure and the chemical potential, we establish rigorously the
relativistic transformation laws for these three intensive quantities in Sec. 11, 12
and 13 respectively. The relativistic force density is established in Sec. 14. The
relativistic continuity equations for the energy and the momentum are derived
from the relativistic continuity equation for the energy-momentum in Sec. 15
and 16, and the relativistic corrections are highlighted. In Sec. 17, we derive a
relativistic continuity equation for the inertia and show how and why it differs
from the continuity equation for the mass that is usually assumed to hold. We
derive the relativistic Euler equation from the relativistic continuity equations
for the momentum and the inertia in Sec. 18 and highlight the relativistic cor-
rections. Finally, we conclude our analysis of the relativistic thermodynamics
of a perfect fluid in Sec. 19. In Appendices Appendix A and Appendix B, we
present the fundamental concepts of relativistic kinematics and dynamics of a
particle, which are the cornerstone of a relativistic theory.
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