  A detailed theory of quantum premeasurement dynamics is presented in which a
unitary composite-system operator that contains the relevant
object-measuring-instrument interaction brings about the final premeasurement
state. It does not include collapse, and it does not consider the environment.
It is assumed that a discrete degenerate or non-degenerate observable is
measured. Premeasurement is defined by the calibration condition, which
requires that every initially statistically sharp value of the measured
observable has to be detected with statistical certainty by the measuring
instrument. The entire theory is derived as a logical consequence of this
definition using the standard quantum formalism. The study has a comprehensive
coverage, hence the article is actually a topical review. Connection is made
with results of other authors, particularly with basic works on premeasurement.
The article is a conceptual review, not a historical one. General exact
premeasurement is defined in 7 equivalent ways. Nondemolition premeasurement,
defined by requiring preservation of any sharp value of the measured
observable, is characterized in 10 equivalent ways. Overmeasurement, i. e., a
process in which the observable is measured on account of being a function of a
finer observable that is actually measured, is discussed. Disentangled
premeasurement, in which, by definition, to each result corresponds only one
pointer-observable state in the final composite-system state, is investigated.
Ideal premeasurement, a special case of both nondemolition premeasurement and
disentangled premeasurement, is defined, and its most important properties are
discussed. Finally, disentangled and entangled premeasurements, in conjunction
with nondemolition or demolition premeasurements, are used for classification
of all premeasurements.
