One-parameter family of closed, radiation-filled Friedmann-Robertson-Walker ``quantum'' universes

Using as an illustrative example the p=1 operator-ordered Wheeler-DeWitt equation for a closed, radiation-filled Friedmann-Robertson-Walker universe, we introduce and discuss the supersymmetric double Darboux method in quantum cosmology. A one-parameter family of ``quantum'' universes and the corresponding ``wavefunctions of the universe" for this case are presentedComment: 7 pp with 2 epsf figs, small corrections to the published pape

Continuum bound states K-long, D_{1}(2420), D_{s1}(2536) and their partners K-short, D_{1}(2400), D*_{sJ}(2463)

The very recently observed $D^{\ast}_{sJ}(2463)$ meson is described as a $J^{P}=1^{+}$ $c\bar{s}$ bound state in a unitarised meson model, owing its existence to the strong OZI-allowed $^{3}P_{0}$ coupling to the nearby $S$-wave $D^{\ast}K$ threshold. By the same non-perturbative mechanism, the narrow axial-vector $D_{s1}(2536)$ resonance shows up as a quasi-bound-state partner embedded in the $D^{\ast}K$ continuum. With the same model and parameters, it is also shown that the preliminary broad $1^{+}$ $D_{1}(2400)$ resonance and the established narrow $1^{+}$ $D_{1}(2420)$ may be similar $c\bar{n}$ partners, as a result of the strong OZI-allowed $^{3}P_{0}$ coupling to the nearby $S$-wave $D^{\ast}\pi$ threshold. The continuum bound states $D_{1}$(2420) and $D_{s1}(2536)$ are found to be mixtures of 33% $^{3}P_{1}$ and 67% $^{1}P_{1}$, whereas their partners $D_{1}(2400)$ and $D^{\ast}_{sJ}(2463)$ have more or less the opposite $^{2S+1}P_1$-state content, but additionally with some $D^{\ast}\pi$ or $D^{\ast}K$ admixture, respectively. The employed mechanism also reproduces the ratio of the $K_{L}$-$K_{S}$ mass difference and the $K_{S}$ width, by describing $K_{L}$ as a bound state embedded in the $\pi\pi$ continuum. The model's results for $J^{P}=1^{+}$ states containing one $b$ quark are also discussed.Comment: 11 pages, plain LaTeX, v2:relation to work of Kokoski and Godfrey in conclusions and more references v3:B-states included. More reference

Supersymmetric Fokker-Planck strict isospectrality

I report a study of the nonstationary one-dimensional Fokker-Planck solutions by means of the strictly isospectral method of supesymmetric quantum mechanics. The main conclusion is that this technique can lead to a space-dependent (modulational) damping of the spatial part of the nonstationary Fokker-Planck solutions, which I call strictly isospectral damping. At the same time, using an additive decomposition of the nonstationary solutions suggested by the strictly isospectral procedure and by an argument of Englefield [J. Stat. Phys. 52, 369 (1988)], they can be normalized and thus turned into physical solutions, i.e., Fokker-Planck probability densities. There might be applications to many physical processes during their transient periodComment: revised version, scheduled for PRE 56 (1 August 1997) as a B

Iso-spectral potential and inflationary quantum cosmology

Using the factorization approach of quantum mechanics, we obtain a family of isospectral scalar potentials for power law inflationary cosmology. The construction is based on a scattering Wheeler-DeWitt solution. These iso-spectrals have new features, they give a mechanism to end inflation, as well as the possibility to have new inflationary epochs. The procedure can be extended to other cosmological models.Comment: 14 pages, 5 figure

Visual histories of sex: collecting, curating, archiving

Increased access to visual archives and the proliferation of digitized images related to sexuality have led a growing number of scholars in recent years to place images and visual practices at the center of critical historical inquiries of sexual desire, subjectivity, and embodiment. At the same time, new critical histories of sexual science serve both to expand the temporal and geographical frames for investigating the historical relationships of sex and visual production, and to generate new lines of inquiry and reshape visual studies more broadly. The contributors to this issue invite us to ask: What new questions and challenges for the study of sex and sexual science are posed by critical studies of the visual? How are new visual methodologies that focus on archives changing the contours of historical knowledge about sex and sexuality? What—and where—are new methodologies still needed? “Visual Archives of Sex” aims to illuminate current research that centers visual media in the history of sexuality and that interrogates contemporary historiographies