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Knowing something of the gestation of these papers, I for one will be very interested to see the ensuing debate. Roger Musson British Geological Survey West Mains Road Edinburgh EH9 3LA tel: +44 (0)131-650-0205 fax: +44 (0)131-667-1877 > -----Original Message----- > From: Tectonics & structural geology discussion list > [mailto:[log in to unmask]] On Behalf Of Falk H. Koenemann > Sent: 26 May 2008 18:24 > To: [log in to unmask] > Subject: stress news > > Hi folks, > > today I have been informed by the chief editor of the > 'International Journal of Modern Physics B' that three papers > have been accepted for publication at once: > > ON THE SYSTEMATICS OF ENERGETIC TERMS IN CONTINUUM MECHANICS, > AND A NOTE ON GIBBS (1877) (date of acceptance May 24) > > POTENTIAL THEORY AND ELASTICITY: A COMMENT ON GURTIN (1972) (May 24) > > AN APPROACH TO DEFORMATION THEORY BASED ON THERMODYNAMIC > PRINCIPLES (May 6) > > > Abstract of 'Systematics & Gibbs': > The systematics of energetic terms as they are taught in > continuum mechanics deviate seriously from standard views in > physics, resulting in a profound misconception. It is > demonstrated that the First Law of Thermodynamics has been > routinely re-interpreted in a sense that would make it > subordinate to Bernoulli's energy conservation law. > Furthermore, it is shown that the attempt by Gibbs to find a > thermodynamic understanding for elastic deformation does not > sufficiently account for all the energetic properties of such > a process. > > > Abstract of 'Gurtin': > In an exhaustive presentation of the linear theory of > elasticity by Gurtin (1972) the author included a chapter on > the relation of the theory of elasticity to the theory of > potentials. Potential theory distinguishes two fundamental > physical categories: divergence-free and divergence-involving > problems. From the criteria given in the source quoted by the > author it is evident that elastic deformation of solids falls > into the latter category. It is documented in this short note > that the author presented volume-constant elastic deformation > as a divergence-free physical process, systematically > ignoring all the information that was available to him that > this is not so. > > In plain English: the guy cheated. He misled an entire > generation of scientists. > > > Abstract of 'Approach': > The Cauchy stress theory has been shown to be profoundly at > variance with the principles of the theory of potentials. > Thus, a new physical approach to deformation theory is > presented which is based on the balance of externally applied > forces and material forces. The equation of state is > generalized to apply to solids, and transformed into vector > form. By taking the derivatives of an external potential and > the material internal energy with respect to the coordinates, > two vector fields are defined for the forces exerted by > surrounding at the system, subject to the boundary > conditions, and vice versa, subject to the material > properties. These vector fields are then merged into a third > one that represents the properties of the loaded state. > Through the work function the force field is then directly > transformed into the displacement field. The approach permits > fully satisfactory prediction of all geometric and energetic > properties of elastic and plastic simple shear. It predicts > the existence of a bifurcation at the transition from > reversible to irreversible behavior whose properties permit > correct prediction of cracks in solids. It also offers a > mechanism for the generation of sheath folds in plastic shear > zones and for turbulence in viscous flow. Finally, an example > is given how to apply the new approach to deformation of a > discrete sample as a function of loading configuration and > sample shape. > > > Phenomena for which my approach delivers fully satisfactory > predictions are: > - S-C fabrics in mylonites, > - elastic-reversible dilatancy, > - orientation of joints in rocks, > - properties of microfabric diagrams for minerals with > simple geometric properties, > - the energetics of elastic and plastic pure shear and > simple shear > deformation, as they are known from experiments, > - the observed orientation of the regional stress field > in California around the San Andreas Fault, > - turbulence in viscous flow, > - generation of sheath folds in plastic shear zones, > - generation of cracks in brittle deformation. > > > > Delivery of the three papers in paper print is scheduled for > July. The PDF files can be downloaded from my website, > > www.elastic-plastic.de > > > Concerning the work done so far, based on Hooke, Euler, > Cauchy, Navier-Stokes, Prandtl-Reuss, Taylor-Bishop-Hill - It > is going to be a spectacle like the Hindenburg at Lakehurst. > No regrets. > > > Falk Koenemann > Aachen, Germany > > -- > > .___________________________________________________________________ > | Dr. Falk H. Koenemann Aachen, Germany | > | | > | Email: [log in to unmask] Phone: *49-241-75885 | > |-------------------------------------------------------------------| > | www.elastic-plastic.de | > |___________________________________________________________________| > > *************************************************************************************************************** This message (and any attachments) is for the recipient only. 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