Addressing Cultural Pluralism from an Evangelical Christian Perspective

The complex issues surrounding cultural pluralism are rapidly turning the public square into a battlefield that divides our country. As Charles Haynes summarized, “At issue for this nation, as for much of the world, is the simple but profound question that runs through modern experience: How will we live with our deepest differences?” (Haynes, 1994). At a time when many citizens of our diverse nation have become disillusioned with the motto e pluribus unum, the Christian higher education community deals with issues involving race, ethnicity, and gender through a variety of responses ranging from isolationism to unqualified inclusion. Evangelical institutions of higher learning are not new to the discussion of multiculturalism. They have rather a rich history of commitment to living out Christ’s commandment to love one’s neighbor as oneself (Mk 12:31) regarding each other through the unity of faith in Christ (Gal 3:28). This paper addresses the historical context for understanding cultural pluralism together with the scriptural and religious imperatives for engaging Christian and secular audiences on this issue. It identifies several of the issues surrounding cultural pluralism faced by evangelicals today, while also developing criteria for celebrating and confronting pluralism. Finally, it articulates strategies for pursuing common ground in the public arena and discusses implications for Christian higher education in addressing cultural pluralism within and beyond the college classroom

Fermi surface topology and low-lying quasiparticle structure of magnetically ordered Fe1+xTe

We report the first photoemission study of Fe1+xTe - the host compound of the newly discovered iron-chalcogenide superconductors. Our results reveal a pair of nearly electron- hole compensated Fermi pockets, strong Fermi velocity renormalization and an absence of a spin-density-wave gap. A shadow hole pocket is observed at the "X"-point of the Brillouin zone which is consistent with a long-range ordered magneto-structural groundstate. No signature of Fermi surface nesting instability associated with Q= pi(1/2, 1/2) is observed. Our results collectively reveal that the Fe1+xTe series is dramatically different from the undoped phases of the high Tc pnictides and likely harbor unusual mechanism for superconductivity and quantum magnetic order.Comment: 5 pages, 4 Figures; Submitted to Phys. Rev. Lett. (2009

Emergence of Fermi pockets in an excitonic CDW melted novel superconductor

A superconducting (SC) state (Tc ~ 4.2K) has very recently been observed upon successful doping of the CDW ordered triangular lattice TiSe$_2$, with copper. Using high resolution photoemission spectroscopy we identify, for the first time, the momentum space locations of the doped electrons that form the Fermi sea of the parent superconductor. With doping, we find that the kinematic nesting volume increases whereas the coherence of the CDW order sharply drops. In the superconducting doping, we observe the emergence of a large density of states in the form of a narrow electron pocket near the \textit{L}-point of the Brillouin Zone with \textit{d}-like character. The \textit{k}-space electron distributions highlight the unconventional interplay of CDW to SC cross-over achieved through non-magnetic copper doping.Comment: 4+ pages, 5 figures; Accepted for publication in Phys. Rev. Lett. (2007

Collective Excitations, Nambu-Goldstone Modes and Instability of Inhomogeneous Polariton Condensates

We study non-equilibrium microcavity-polariton condensates (MPCs) in a harmonic potential trap theoretically. We calculate and analyze the steady state, collective-excitation modes and instability of MPCs. Within excitation modes, there exist Nambu-Goldstone modes that can reveal the pattern of the spontaneous symmetry breaking of MPCs. Bifurcation of the stable and unstable modes is identified in terms of the pumping power and spot size. The unstable mechanism associated with the inward supercurrent flow is characterized by the existence of a supersonic region within the condensate.Comment: 16 pages, 3 figure

Complete d-Band Dispersion and the Mobile Fermion Scale in NaxCoO2

We utilize fine-tuned polarization selection coupled with excitation-energy variation of photoelectron signal to image the \textit{complete d}-band dispersion relation in sodium cobaltates. A hybridization gap anticrossing is observed along the Brillouin zone corner and the full quasiparticle band is found to emerge as a many-body entity lacking a pure orbital polarization. At low dopings, the quasiparticle bandwidth (Fermion scale, many-body \textit{E$_F$} $\sim$ 0.25 eV) is found to be smaller than most known oxide metals. The low-lying density of states is found to be in agreement with bulk-sensitive thermodynamic measurements for nonmagnetic dopings where the 2D Luttinger theorem is also observed to be satisfied.Comment: 4+ pages, 5 Fig

An upper limit for the water outgassing rate of the main-belt comet 176P/LINEAR observed with Herschel/HIFI

176P/LINEAR is a member of the new cometary class known as main-belt comets (MBCs). It displayed cometary activity shortly during its 2005 perihelion passage that may be driven by the sublimation of sub-surface ices. We have therefore searched for emission of the H2O 110-101 ground state rotational line at 557 GHz toward 176P/LINEAR with the Heterodyne Instrument for the Far Infrared (HIFI) on board the Herschel Space Observatory on UT 8.78 August 2011, about 40 days after its most recent perihelion passage, when the object was at a heliocentric distance of 2.58 AU. No H2O line emission was detected in our observations, from which we derive sensitive 3-sigma upper limits for the water production rate and column density of < 4e25 molec/s and of < 3e10 cm^{-2}, respectively. From the peak brightness measured during the object's active period in 2005, this upper limit is lower than predicted by the relation between production rates and visual magnitudes observed for a sample of comets by Jorda et al. (2008) at this heliocentric distance. Thus, 176P/LINEAR was likely less active at the time of our observation than during its previous perihelion passage. The retrieved upper limit is lower than most values derived for the H2O production rate from the spectroscopic search for CN emission in MBCs.Comment: 5 pages, 2 figures. Minor changes to match published versio

Semimetal to semimetal charge density wave transition in 1T-TiSe2_2

We report an infrared study on 1$T$-TiSe$_2$, the parent compound of the newly discovered superconductor Cu$_x$TiSe$_2$. Previous studies of this compound have not conclusively resolved whether it is a semimetal or a semiconductor: information that is important in determining the origin of its unconventional CDW transition. Here we present optical spectroscopy results that clearly reveal that the compound is metallic in both the high-temperature normal phase and the low-temperature CDW phase. The carrier scattering rate is dramatically different in the normal and CDW phases and the carrier density is found to change with temperature. We conclude that the observed properties can be explained within the scenario of an Overhauser-type CDW mechanism.Comment: 4 pages, 4 page

Low-lying quasiparticle states and hidden collective charge instabilities in parent cobaltate superconductors (NaxCoO2)

We report a state-of-the-art photoemission (ARPES) study of high quality single crystals of the NaxCoO2 series focusing on the fine details of the low-energy states. The Fermi velocity is found to be small (< 0.5 eV.A) and only weakly anisotropic over the Fermi surface at all dopings setting the size of the pair wavefunction to be on the order of 10-20 nanometers. In the low doping regime the exchange inter-layer splitting vanishes and two dimensional collective instabilities such as 120-type fluctuations become kinematically allowed. Our results suggest that the unusually small Fermi velocity and the unique symmetry of kinematic instabilities distinguish cobaltates from other unconventional oxide superconductors such as the cuprates or the ruthenates.Comment: Accepted for publication in Phys. Rev. Lett. (2006

Quasiparticle coherence and the nature of the metal-insulator phase transition in Nax_xCoO2_2

Layered cobaltates embody novel realizations of correlated quantum matter on a spin-1/2 triangular lattice. We report a high-resolution systematic photoemission study of the insulating cobaltates (Na1/2CoO2 and K1/2CoO2). Observation of single-particle gap opening and band-folding provides direct evidence of anisotropic particle-hole instability on the Fermi surface due to its unique topology. Kinematic overlap of the measured Fermi surface is observed with the $\sqrt{3}$x$\sqrt{3}$ cobalt charge-order Brillouin zone near x=1/3 but not at x=1/2 where insulating transition is actually observed. Unlike conventional density-waves, charge-stripes or band insulators, the on-set of the gap depends on the quasiparticle's quantum coherence which is found to occur well below the disorder-order symmetry breaking temperature of the crystal (the first known example of its kind).Comment: 4+ pages, 5 figure