Newton's "Experimental Philosophy"

My talk today will be about Newton’s avowed methodology, and specifically the place of experiment in his conception of science, and how his ideas changed significantly over the course of his career. I also want to look at his actual scientific practice and see how this influenced his views on the nature of the experimental sciences

Principles of equilibrium statistical mechanics revisited: The idea of vortex energy

We show that the law of energy conservation with the fact of matter stability imply the existence of energy complementary to that given by the function of states of interacting systems and treated, with the environment, the function of states of interacting extended systems. The complementary energy, we called it vortex, is integral, not quantized, and causes trends contrary to that prescribed by equilibrium statistical mechanics. We formulate its principles and theorems, and question traditional insights in thermodynamics, entropy law, phase transitions, persistent currents, Brownian motion.Comment: 8 pages. Refined the title and wording, corrected typos, added the acknowledgement. arXiv admin note: substantial text overlap with arXiv:1109.2605; refined the title, clarified some phrases, refined concluding remarks, results unchange

Photoassociation adiabatic passage of ultracold Rb atoms to form ultracold Rb_2 molecules

We theoretically explore photoassociation by Adiabatic Passage of two colliding cold ^{85}Rb atoms in an atomic trap to form an ultracold Rb_2 molecule. We consider the incoherent thermal nature of the scattering process in a trap and show that coherent manipulations of the atomic ensemble, such as adiabatic passage, are feasible if performed within the coherence time window dictated by the temperature, which is relatively long for cold atoms. We show that a sequence of ~2*10^7 pulses of moderate intensities, each lasting ~750 ns, can photoassociate a large fraction of the atomic ensemble at temperature of 100 microkelvin and density of 10^{11} atoms/cm^3. Use of multiple pulse sequences makes it possible to populate the ground vibrational state. Employing spontaneous decay from a selected excited state, one can accumulate the molecules in a narrow distribution of vibrational states in the ground electronic potential. Alternatively, by removing the created molecules from the beam path between pulse sets, one can create a low-density ensemble of molecules in their ground ro-vibrational state.Comment: RevTex, 23 pages, 9 figure

Orbital Magnetism in Two-dimensional Integrable Systems

We study orbital magnetism of a degenerate electron gas in a number of two-dimensional integrable systems, within linear response theory. There are three relevant energy scales: typical level spacing, the energy related to the inverse time of flight across the system, and the Fermi energy. Correspondingly, there are three distinct temperature regimes: microscopic, mesoscopic, and macroscopic. In the first two regimes there are large finite-size effects in the magnetic susceptibility, whereas in the third regime the susceptibility approaches its macroscopic value. In some cases, such as a quasi-one-dimensional strip or a harmonic confining potential, it is possible to obtain analytic expressions for the susceptibility in the entire temperature range.Comment: 28 pages, Latex, 4 Postscript figure

Judicial Incentives and Indeterminacy in Substantive Review of Administrative Decisions

Uppsatsen tydliggör och beskriver innehållet i elva lokala överenskommelser (LÖK) mellan civilsamhället och offentlig sektor. Studien visar också hur relationen mellan parterna avspeglas i texterna. Uppsatsen visar också på hur olika idéer och synsätt i överenskommelserna kan få praktiska konsekvenser för civilsamhället