<< WebHome

main page: GrassmannCosmoFun2009

These are just rough notes - feel free to correct them, add links, etc. from the Grassmann ian Conference in Fundamental Cosmology (Grasscosmofun'09). These are not official proceedings. The speakers might even disagree that they said anything even vaguely related to what are in these online notes! Don't say you weren't warned.

Tues 15 Sep 2009

  • KOWALSKI - some recent SNe Ia results
  • John BARROW - varying alpha results:
    • Chand, Srianand et al. 2004 results wrong because started from assuming alpha = constant (instead of free parameter) and then seeing if it can be varied; and because their best fit chi^2 is not a nice parabola and they missed fitting many lines; someone has reanalysed the data and got back to the varying alpha result;
    • varying alpha for various absorption lines (Fe II(?), ...)
    • results from 3 groups agree dalpha/alpha \approx -0.6 \times 10^{-5}
    • varying alpha model BSBM - scalar field model - interpret Webb et al. results
    • BSBM => violation of weak equivalence principle
    • \Rightarrow (a-A)/(a+A) \sim 10^{-13}
    • present bounds = 10^{-12} - probably need to go to space to get stronger constraints, e.g. 10^{-18}
    • ... bouncing BSBM models....
  • Pouria PEDRAM
    • Wheeler de Witt equation
  • Piotr DZIERZAK
    • Bianchi I type model and LQC
    • T^3 model !!!
    • ... Big Bounce at classical level
    • algebra of observables:
    • aim: singularity aspects of the model in terms of observables
  • E. MELAS
    • canonical QQ for geometries admitting maximally symmetric 2D surfaces
    • final expression for WDW eqn
    • Conclusion:
      • TODO:
        • (1) render finite the 3 smooth functionals y^1, y^2, y^3
        • (2) select an appropriate inner product
      • requires only first derivatives, cf. Cartan-Karlhede which requires up to the 7th derivatives
  • Mariusz DABROWSKI
    • Big Rip, SFS (Sudden Future Singularity), TLB, radially inhomogeneous pressure models, possible solutions to DE with sudden singularity (in future(?))
  • Przemyslaw MALKIEWICZ
    • see papers with Piechocki - strings, membranes, in time-dependent orbifold
  • Ghodsi HODA
    • working with Martin Hendry
    • q = fn(z), differs for SFS model vs standard concordance model
    • with m=constant, SFS fails to fit all fashionable data sets simultaneously
  • Boguslaw BRODA (Lodz)
    • DE from quantum flucutations
    • ... get rho approx rho_experimental where rho_experimental = rho_Lambda (?)
    • other interesting approaches: holographic DE e.g. Ricci DE which is similar to Broda's approach
    • Volovik approach - about 10 papers on arXiv.org

-- BoudRoukema - 15 Sep 2009
Topic revision: r1 - 15 Sep 2009, BoudRoukema
This site is powered by FoswikiCopyright © CC-BY-SA by the contributing authors. All material on this collaboration platform is copyrighted under CC-BY-SA by the contributing authors unless otherwise noted.
Ideas, requests, problems regarding Foswiki? Send feedback