8,648 research outputs found
Electronic States and Transport Phenomena in Quantum Dot Systems
Electronic states and transport phenomena in semiconductor quantum dots are
studied theoretically. Taking account of the electron-electron Coulomb
interaction by the exact diagonalization method, the ground state and low-lying
excited states are calculated as functions of magnetic field. Using the
obtained many-body states, we discuss the temperature dependence of the
conductance peaks in the Coulomb oscillation. In the Coulomb blockade region,
elastic and inelastic cotunneling currents are evaluated under finite bias
voltages. The cotunneling conductance is markedly enhanced by the Kondo effect.
In coupled quantum dots, molecular orbitals and electronic correlation
influence the transport properties.Comment: Review paper of our work, to appear in Proc. Int. Symp. on Formation,
Physics and Device Application of Quantum Dot Structures (QDS 2000, Sapporo,
Japan), Jpn. J. Appl. Phys. [11 pages, 6 figures
Sellars on Functionalism and Normativity
The term ‘functionalism’ is usually heard in connection with the philosophy of mind or cognition. The functionalism of Wilfrid Sellars, however, is in the first instance as response to the worries about the metaphysics not of mental states, but of meaning. Only late in his career did Sellars explore the possibility of extending his functionalism into an account of cognition. It has been suggested, though, that Sellars’ extension of his functionalist theory into subpersonal territory is not successful. In particular, there is a worry abroad that in order to be a functionalist about cognitive states, Sellars must succumb to a special form of the Myth of the Given. In this essay I will review and elucidate what I take to be the structure of Sellars’ functionalism, defending it from this worry. I will suggest a resolution of some apparent textual contradictions based in part on the chronology of Sellars’ writing, with the assumption that later writings express Sellars’ more nuanced views.
Draft of 2009
The perturbation of the Seiberg-Witten equations revisited
We introduce a new class of perturbations of the Seiberg-Witten equations.
Our perturbations offer flexibility in the way the Seiberg-Witten invariants
are constructed and also shed a new light to LeBrun's curvature inequalities.Comment: typos correcte
The hamburger theorem
We generalize the ham sandwich theorem to measures in as
follows. Let be absolutely continuous finite
Borel measures on . Let for , and assume that . Assume that for every . Then there
exists a hyperplane such that each open halfspace defined by
satisfies for every
and . As a
consequence we obtain that every -colored set of points in
such that no color is used for more than points can be
partitioned into disjoint rainbow -dimensional simplices.Comment: 11 pages, 2 figures; a new proof of Theorem 8, extended concluding
remark
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