These entities are problematic in relativity due to their infinite speed of sound.
The motion of these objects in Minkowski space can only consist of Fermi congruences and Killing congruences, and in that situation, they only have three degrees of freedom. These entities undergo motions that are characterized by the Lie derivative of the metric with respect to the relative velocity field equalling zero. The set of all possible motions of these things is the group SE(3). (*) d'Alembert's principle provides a set of conditions for when a system of these entities are at equilibrium. The rotations of these entities are described by the Euler equations, while their moments of inertia can be represented with the inertia matrix. These entities are problematic in relativity due to their infinite speed of sound. According to the principle of transmissibility, a force applied to one of these has the same effect no matter where on the line of action it is placed. For 10 points, name these idealized bodies which cannot be deformed.
The motion of these objects in Minkowski space can only consist of Fermi congruences and Killing congruences, and in that situation, they only have three degrees of freedom.
rigid bodies 