Application of Einstein’s Methods in a Quantum Theory of Radiation

Einstein showed in his seminal paper on radiation that molecules with a quantum-theoretical distribution of states in thermal equilibrium are in dynamical equilibrium with the Planck radiation. The method he used assigns coordinates fixed with respect to molecules to derive the A and B coefficients, and fixed relative to laboratory coordinates to specify their thermal motion. The resulting dynamical equilibrium between quantum mechanical and classically defined statistics is critically dependent upon considerations of momentum exchange. When Einstein’s methods relating classical and quantum mechanical statistical laws are applied to the level of the single quantum oscillator they show that matrix mechanics describes the external appearances of an atom as determined by photon-electron interactions in laboratory coordinates, and wave mechanics describes an atom’s internal structure according to the Schrödinger wave equation. Non-commutation is due to the irreversibility of momentum exchange when transforming between atomic and laboratory coordinates. This allows the “rotation” of the wave function to be interpreted as the changing phase of an electromagnetic wave. In order to describe the momentum exchange of a quantum oscillator the Hamiltonian model of atomic structure is replaced by a Lagrangian model that is formulated with equal contributions from electron, photon, and nucleus. The fields of the particles superpose linearly, but otherwise their physical integrity is maintained throughout. The failure of past and present theoretical models to include momentum is attributed to the overwhelming requirement of human visual systems for an explicit stimulus.

X-Ray Photon Correlation Spectroscopy with Coherent Nanobeams: A Numerical Study

X-ray photon correlation spectroscopy accesses a wide variety of dynamic phenomena at the nanoscale by studying the temporal correlations among photons that are scattered by a material in dynamical equilibrium when it is illuminated with a coherent X-ray beam. The information that is obtained is averaged over the illuminated area, which is generally of the order of several square microns. We propose here that more local information can be obtained by using nanobeams with great potential for the study of heterogeneous systems and show the feasibility of this approach with the support of numerical simulations.

RAF autoinhibition and 14-3-3 proteins promote paradoxical activation

RAF kinase inhibitors can actually increase RAF kinase signaling. This process, which is commonly referred to as “paradoxical activation” (PA), is incompletely understood. RAF kinases are regulated by autoinhibitory conformational changes, and the role of these conformational changes in PA is unclear. Our mathematical investigations find that PA can result from a dynamical equilibrium between autoinhibited and non-autoinhibited forms of RAF, along with the RAF inhibitor stabilizing the non-autoinhibited form. We also investigate whether PA is influenced by 14-3-3 proteins, which can both stabilize RAF autoinhibition and RAF dimerization. Using both computational and experimental methods we demonstrate that 14-3-3 proteins potentiate PA. Third generation RAF inhibitors normally display minimal to no PA. Our mathematical modeling led us to hypothesize that increased 14-3-3 expression should also amplify PA for these agents. Subsequent experiments support our hypothesis and show that 14-3-3 overexpression increases PA in these third generation RAF inhibitors, effectively “breaking” these “paradox breakers” and pan-RAF inhibitors. We have therefore created and experimentally validated a robust mechanism for PA based solely on equilibrium dynamics of canonical interactions in RAF signaling.

MOCCA-SURVEY Database I: Dissolution of tidally filling star clusters harboring black hole subsystem

We investigate the dissolution process of star clusters embedded in an external tidal field and harboring a subsystem of stellar-mass black hole. For this purpose we analyzed the MOCCA models of real star clusters contained in the Mocca Survey Database I. We showed that the presence of a stellar-mass black hole subsystem in tidally filling star cluster can lead to abrupt cluster dissolution connected with the loss of cluster dynamical equilibrium. Such cluster dissolution can be regarded as a third type of cluster dissolution mechanism. We additionally argue that such a mechanism should also work for tidally under-filling clusters with a top-heavy initial mass function.