Indeed from the standpoint of modern physics the existence of rigid bodies and rigid body motion is not a fundamental self-evident requirement anymore, but only a special property that obtains in a definite limiting case of the physics of classical mechanics and geometry.
Huggett (2006) defends a similar position of absolutism about motion, but relationism about space; he argues — in the case of Newtonian physics — that fundamentally there is nothing to space but relations between bodies, but that absolute motions supervene — not on the relations at any one time — but on the entire history of relations.
According to Kepler, each branch of knowledge must, in principle, be reducible to geometry if it is to be accepted as knowledge in the strong sense (although, in the case of the physics, this condition is, as the AN emphasizes, only a necessary and not a sufficient condition).
In the special case of linear Physics-based motion models, the analytical solution for the state of the vehicles at a specific time can easily be derived by solving the linear differential equations of the motion model.
Were this not the case, the laws of physics might never have been elucidated.
In any case, an account of physics based on the impossibility of walking on water, or a section in chemistry that turns on the reactions that transform it into an alcoholic beverage would make feeble reading indeed.
And if that physical analogy cannot be sustained, then the empirical success of renormalization in CQFT leaves the physical reasons for this success in the dark, in contrast to the case of condensed matter physics, where the physical basis for the empirical success of renormalization is intelligible, namely the fact that matter is discrete at atomic length scales.
Being a particular case of condensed matter physics, it is very unlikely that the physics of life can be properly understood without quantum theory.
One operating mode with higher magnetic field and conservative physics is presented, which could serve as a backup CFETR baseline in case of shortfall in physics performance.
