Resolution of a paradox in kinematic turbulence theory

view Abstract Citations (2) References (10) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Resolution of a Paradox in Kinematic Turbulence Theory Lerche, I. Abstract Using the thermal conduction of heat in an infinite, incompressible fluid possessing a turbulent velocity field as an illustration, we show that the existence of growing modes of a system is by no means a guarantee that the system at hand is unstable. We show that for our problem such growing modes are mathematically correct but physically absurd, giving rise, therefore, to a paradox. They are eliminated in our illustrative problem by the requirement of physical causality therefore resolves the paradox. Based on the results obtained from the illustrative problem we set up guidelines which m'tst be applied to every physical problem involving random-function theory to determine which of the mathematically obtained modes are physically permissible. The only sure way for selecting the physically relevant modes is contained in a statement of physical causality. Publication: The Astrophysical Journal Pub Date: June 1972 DOI: 10.1086/151491 Bibcode: 1972ApJ...174..309L full text sources ADS |