The grounding argument against non-reductive moral realism

The supervenience argument against non-reductive moral realism threatens to rule out the existence of irreducibly normative properties by establishing that for every normative property there is a corresponding non-normative property that is necessarily co-extensive with it. This chapter identifies a hyperintensional analogue of the supervenience argument that threatens non-reductionism even within a hyperintensional setting by establishing that for every normative property there is a corresponding non-normative property that has the very same grounds and is, accordingly, hyperintensionally equivalent. It is then argued that non-reductionism can nevertheless be salvaged by distinguishing the different grounding relations that are involved in grounding the normative property and the corresponding non-normative property. Non-reductionist versions of moral realism thus turn out to be committed to there being irreducibly different grounding relations.</p

Comment on "Anomalous heat conduction and anomalous diffusion in one-dimensional systems"

We comment on a recent paper by Li and Wang [Phys. Rev. Lett. 91, 044301 (2003)], and argue that their results violate the non-existence of a characteristic time scale in subdiffusive systems.Comment: 1 page, REVTeX, accepted to Phys. Rev. Let

Is Rho-Meson Melting Compatible with Chiral Restoration?

Utilizing in-medium vector spectral functions which describe dilepton data in ultra-relativistic heavy-ion collisions, we conduct a comprehensive evaluation of QCD and Weinberg sum rules at finite temperature. The starting point is our recent study in vacuum, where the sum rules have been quantitatively satisfied using phenomenological axial-/vector spectral functions which describe hadronic tau-decay data. In the medium, the temperature dependence of condensates and chiral order parameters is taken from thermal lattice QCD where available, and otherwise estimated from a hadron resonance gas. Since little is known about the in-medium axial-vector spectral function, we model it with a Breit-Wigner ansatz allowing for smooth temperature variations of its width and mass parameters. Our study thus amounts to testing the compatibility of the $\rho$-broadening found in dilepton experiments with (the approach toward) chiral restoration, and thereby searching for viable in-medium axial-vector spectral functions.Comment: 8 pages, 4 figures, updated to be consistent with published versio

Non-Markovian decoherence in the adiabatic quantum search algorithm

We consider an adiabatic quantum algorithm (Grover's search routine) weakly coupled to a rather general environment, i.e., without using the Markov approximation. Markovian errors generally require high-energy excitations (of the reservoir) and tend to destroy the scalability of the adiabatic quantum algorithm. We find that, under appropriate conditions (such as low temperatures), the low-energy (i.e., non-Markovian) modes of the bath are most important. Hence the scalability of the adiabatic quantum algorithm depends on the infra-red behavior of the environment: a reasonably small coupling to the three-dimensional electromagnetic field does not destroy the scaling behavior, whereas phonons or localized degrees of freedom can be problematic. PACS: 03.67.Pp, 03.67.Lx, 03.67.-a, 03.65.Yz

Quantitative sum rule analysis of low-temperature spectral functions

We analyze QCD and Weinberg-type sum rules in a low-temperature pion gas using vector and axial-vector spectral functions following from the model-independent chiral-mixing scheme. Toward this end we employ recently constructed vacuum spectral functions with ground and first-excited states in both channels and a universal perturbative continuum; they quantitatively describe hadronic tau-decay data and satisfy vacuum sum rules. These features facilitate the implementation of chiral mixing without further assumptions, and lead to in-medium spectral functions which exhibit a mutual tendency of compensating resonance and dip structures, suggestive for an approach toward structureless distributions. In the sum rule analysis, we account for pion mass corrections, which turn out to be significant. While the Weinberg sum rules remain satisfied even at high temperatures, the numerical evaluation of the QCD sum rules for vector and axial-vector channels reveals significant deviations setting in for temperatures beyond ~140 MeV, suggestive of additional physics beyond low-energy chiral pion dynamics.Comment: 8 pages, 3 figure

On the non-perturbative realization of QCD gauge-invariance

A few years ago the use of standard functional manipulations was demonstrated to imply an unexpected property satisfied by the fermionic Green's functions of QCD: effective locality. This feature of QCD is non-perturbative as it results from a full integration of the gluonic degrees of freedom. In this paper, previous derivations of effective locality are reviewed, corrected, and enhanced. Focussing on the way non-abelian gauge invariance is realized in the non-perturbative regime of QCD, the deeper meaning of effective locality is discussed.Comment: 18 page

A First Experimental Limit on In-matter Torsion from Neutron Spin Rotation in Liquid He-4

We report the first experimental upper bound to our knowledge on possible in-matter torsion interactions of the neutron from a recent search for parity violation in neutron spin rotation in liquid He-4. Our experiment constrains a coefficient $\zeta$ consisting of a linear combination of parameters involving the time components of the torsion fields $T^\mu$ and $A^\mu$ from the nucleons and electrons in helium which violates parity. We report an upper bound of $|\zeta|<9.1x10^{-23}$ GeV at 68% confidence level and indicate other physical processes that could be analyzed to constrain in-matter torsion.Comment: 12 pages, typo correcte