The Philosophy of Vacuum Part 29. Physicists will find it extremely interesting, covering, as it does, technical subjects in an accessible way. For those with the necessary expertise, this book will provide an illuminating and authoritative exposition of a many-sided subject." -John D. Barrow, Times Literary Supplement. | Theory of Vacuum 273 First relativities including Einstein s fix endosystem and exosystem and merely permute the descriptors among each other. There is really only one Experimenter in classical mechanics who measures everything. Second relativities like the Dirac quantum transformation theory are more general they fix the endosystem but change the experiment one may determine the x component of spin another the y. There is a genuine plurality of experimenters in quantum theory but they all look at the same endosystem. Third relativity shifts the quantum partition between exosystem and endosystem one endosystem is the nucleus of the atom another includes the electrons as well. The third relativity principle is Descriptions of the system with different partitions are mutually consistent. To my knowledge this was first used by Von Neumann in his theory of measurement when he postulates that the determinations by an experimenter I of an experimentee III do not depend on whether the apparatus II is lumped with I or III. Since third relativity is properly stronger than the relativity principles of general relativity it may conceivably provide a stronger restriction of the dynamical principle. 6 Summary In diachronic theories the vacuum carries all the information of the dynamical law. QND is a diachronic theory that fuses quantum and relativity principles in a fundamental and locally finite way. What is usually called unification keeps the vertical structure of physics more or less intact and seeks a horizontal merger on the top levels. In QND particles are defects in the vacuum network and their unification is a consequence of a vertical merger of all the levels of the usual quantum field theory quantum predicate algebra quantum kinematics quantum topology and quantum chronometry into the one of QND. Minkowski space-time is a macroscopic quantum effect with an underlying periodic condensation. Defects in this periodic structure give rise naturally to gauge fields. The .