Footnotes:
[1]
http://arxiv.org/abs/hep-th/0405279
Statistical analysis of the supersymmetry breaking scale
Authors:Michael R. Douglas (Rutgers/IHES/Caltech)
(Submitted on 30 May 2004 (v1), last revised 29 Jun 2004 (this version, v4))
Abstract: We discuss the question of what type and scale of supersymmetry breaking might be statistically favored among vacua of string/M theory, building on comments in Denef and Douglas, hep-th/0404116.
Comments: 8 pp. Latex (v4: we identify a serious error in the original argument, and attempt to address it.)
Subjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
Cite as: arXiv:hep-th/0405279v4
[2]
http://arxiv.org/abs/hep-th/0411183
Distributions of nonsupersymmetric flux vacua
Authors:Frederik Denef, Michael R. Douglas
(Submitted on 19 Nov 2004 (v1), last revised 15 Mar 2005 (this version, v3))
Abstract: We continue the study of the distribution of nonsupersymmetric flux vacua in IIb string theory compactified on Calabi-Yau manifolds, as in hep-th/0404116. We show that the basic structure of this problem is that of finding eigenvectors of the matrix of second derivatives of the superpotential, and that many features of the results are determined by features of the generic ensemble of such matrices, the CI ensemble of Altland and Zirnbauer originating in mesoscopic physics. We study some simple examples in detail, exhibiting various factors which can favor low or high scale supersymmetry breaking.
Comments: 28 pages, JHEP Latex format. v2: a correction further favoring high scale, v3: minor clarifications
Subjects: High Energy Physics - Theory (hep-th)
Journal reference: JHEP 0503:061,2005
DOI: 10.1088/1126-6708/2005/03/061
Cite as: arXiv:hep-th/0411183v3
[3]
http://arxiv.org/abs/hep-th/0504026
Can we predict $\Lambda$ for the Non-SUSY sector of the Landscape ?
Authors:Laura Mersini-Houghton
(Submitted on 4 Apr 2005 (v1), last revised 17 Aug 2005 (this version, v2))
Abstract: We propose a new selection criteria for predicting the most probable wavefunction of the universe that propagates on the string landscape background, by studying its dynamics from a quantum cosmology view. Previously we applied this proposal to the $SUSY$ sector of the landscape. In this work the dynamic selection criterion is applied to the investigation of the non-$SUSY$ sector.In the absence of detailed information about its structure, it is assumed that this sector has a stochastic distribution of vacua energies.The calculation of a distribution probability for the cosmological constants $\Lambda_{eff}$, obtained from the density of states $\rho$, indicates that the most probable wavefunction is peaked around universes with zero $\Lambda_{eff}$. In contrast to the {\it extended wavefunction} solutions found for the $SUSY$ sector with $N$-vacua and peaked around $\Lambda_{eff}\simeq \frac{1}{N^2}$, wavefunctions residing on the non-$SUSY$ sector exhibit {\it Anderson localization}.Although minisuperspace is a limited approach it presently provides a dynamical quantum selection rule for the most probable vacua solution from the landscape.
Comments: 6 pages, 1 figure
Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: Class.Quant.Grav. 22 (2005) 3481-3490
DOI: 10.1088/0264-9381/22/17/009
Cite as: arXiv:hep-th/0504026v2
And [3]
http://arxiv.org/abs/hep-th/0410213
Birth of the Universe from the Landscape of String Theory
Authors:Archil Kobakhidze, Laura Mersini-Houghton
(Submitted on 20 Oct 2004)
Abstract: We show that a unique, most probable and stable solution for the wavefunction of the universe, with a very small cosmological constant $\Lambda_1 \simeq (\frac{\pi}{l_p N})^2$, can be predicted from the supersymmetric minisuperspace with $N$ vacua, of the landscape of string theory without reffering to the antropic principle. Due to the nearest neighbor tunneling in moduli space lattice, the $N$-fold degeneracy of vacua is lifted and a discrete spectrum of bound state levels over the whole minisuperspace emerges. $SUSY$ is spontaneously broken by these bound states, with discrete nonzero energy levels $\Lambda_s \simeq (\frac{s \pi}{l_p N})^2$, $s = 1,2,..$.
Comments: 4 pp, no figures
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: Eur.Phys.J. C49 (2007) 869-873
DOI: 10.1140/epjc/s10052-006-0155-9
Cite as: arXiv:hep-th/0410213v1
And [3]
Wavefunction of the Universe on the Landscape
Authors:Laura Mersini-Houghton
(Submitted on 23 Dec 2005)
Abstract: This talk reviews the proposal for dynamically selecting the most probable wavefunction of the universe propagating on the landscape of string theory, by means of quantum cosmology. Talk given at 'Albert Einstein Century International Conference'-UNESCO, Paris July 18-22 2005.
Comments: 7 pgs., 1 fig
Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: In "Einstein's Jury: The Race to Test Relativity" by Jeffrey Crelinsten, Princeton University Press, 2006
DOI: 10.1063/1.2399686
Cite as: arXiv:hep-th/0512304v1
[4]
http://arxiv.org/abs/hep-th/0511102
Why the Universe Started from a Low Entropy State
Authors:R. Holman, L. Mersini-Houghton
(Submitted on 9 Nov 2005 (v1), last revised 11 Dec 2006 (this version, v3))
Abstract: We show that the inclusion of backreaction of massive long wavelengths imposes dynamical constraints on the allowed phase space of initial conditions for inflation, which results in a superselection rule for the initial conditions. Only high energy inflation is stable against collapse due to the gravitational instability of massive perturbations. We present arguments to the effect that the initial conditions problem {\it cannot} be meaningfully addressed by thermostatistics as far as the gravitational degrees of freedom are concerned. Rather, the choice of the initial conditions for the universe in the phase space and the emergence of an arrow of time have to be treated as a dynamic selection.
Comments: 12 pages, 2 figs. Final version; agrees with accepted version in Phys. Rev. D
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: Phys.Rev.D74:123510,2006
DOI: 10.1103/PhysRevD.74.123510
Cite as: arXiv:hep-th/0511102v3
[5]
http://arxiv.org/abs/hep-th/0612142
Cosmological Avatars of the Landscape II: CMB and LSS Signatures
Authors:R. Holman (Carnegie Mellon University), Laura Mersini-Houghton (UNC-Chapel Hill), Tomo Takahashi (Saga University)
(Submitted on 13 Dec 2006)
Abstract: This is the second paper in the series that confronts predictions of a model of the landscape with cosmological observations. We show here how the modifications of the Friedmann equation due to the decohering effects of long wavelength modes on the wavefunction of the Universe defined on the landscape leave unique signatures on the CMB spectra and large scale structure (LSS). We show that the effect of the string corrections is to suppress $\sigma_8$ and the CMB $TT$ spectrum at large angles, thereby bringing WMAP and SDSS data for $\sigma_8$ into agreement. We find interesting features imprinted on the matter power spectrum $P(k)$: power is suppressed at large scales indicating the possibility of primordial voids competing with the ISW effect. Furthermore, power is enhanced at structure and substructure scales, $k\simeq 10^{-2-0} h~{\rm Mpc}^{-1}$. Our smoking gun for discriminating this proposal from others with similar CMB and LSS predictions come from correlations between cosmic shear and temperature anisotropies, which here indicate a noninflationary channel of contribution to LSS, with unique ringing features of nonlocal entanglement displayed at structure and substructure scales.
Comments: 7 pages, 4 figures
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: Phys.Rev.D77:063511,2008
DOI: 10.1103/PhysRevD.77.063511
And [5]
http://arxiv.org/abs/hep-th/0611223
Cosmological Avatars of the Landscape I: Bracketing the SUSY Breaking Scale
Authors:R. Holman (Carnegie Mellon University), L. Mersini-Houghton (UNC-Chapel Hill), Tomo Takahashi (Saga University)
(Submitted on 21 Nov 2006)
Abstract: We investigate the effects of quantum entanglement between our horizon patch and others due to the tracing out of long wavelength modes in the wavefunction of the Universe as defined on a particular model of the landscape. In this, the first of two papers devoted to this topic, we find that the SUSY breaking scale is bounded both above {\em and} below: $10^{-10} M_{\rm P}\leq M_{\rm SUSY}\leq 10^{-8} M_{\rm P}$ for $GUT$ scale inflation. The lower bound is at least five orders of magnitude larger than the expected value of this parameter and can be tested by LHC physics.
Comments: 7 pages, 1 figure
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: Phys.Rev.D77:063510,2008
DOI: 10.1103/PhysRevD.77.063510
Cite as: arXiv:hep-th/0611223v1
And [5]
http://arxiv.org/abs/0810.5388
'Tilting' the Universe with the Landscape Multiverse: The 'Dark' Flow
Authors:L. Mersini-Houghton, R. Holman
(Submitted on 30 Oct 2008)
Abstract: The theory for the selection of the initial state of the universe from the landscape multiverse predicts superhorizon inhomogeneities induced by nonlocal entanglement of our Hubble volume with modes and domains beyond the horizon. Here we show these naturally give rise to a bulk flow with correlation length of order horizon size. The modification to the gravitational potential has a characteristic scale $L_{1} \simeq 10^{3} H^{-1}$, and it originates from the preinflationary remnants of the landscape. The 'tilt' in the potential induces power to the lowest CMB multipoles, with the dominant contribution being the dipole and next, the quadrupole. The induced multipoles $l \le 2$ are aligned with an axis normal to their alignment plane being oriented along the preferred frame determined by the dipole. The preferred direction is displayed by the velocity field of the bulk flow relative to the expansion frame of the universe. The parameters are tightly constrained thus the derived modifications lead to robust predictions for testing our theory. The 'dark' flow was recently discovered by Kashlinsky et al. to be about $700 km/s$ which seems in good agreement with our predictions for the induced dipole of order $3 \mu K$. Placed in this context, the discovery of the bulk flow by Kashlinsky et al. becomes even more interesting as it may provide a probe of the preinflationary physics and a window onto the landscape multiverse.
Comments: 7 pgs, 2 figs
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
Journal reference: JCAP 0902:006,2009
DOI: 10.1088/1475-7516/2009/02/006
Cite as: arXiv:0810.5388v1 [hep-th]
[6]
P. J. Steinhardt, in The Very Early Universe, Proceedings of the Nuffield Workshop, Cambridge, 21
June ??? 9 July, 1982, eds:
http://books.google.com/books?id=Lq...m=3&sqi=2&ved=0CCsQ6AEwAg#v=onepage&q&f=false
G.W. Gibbons, S.W. Hawking, and S.T.C. Siklos (Cambridge University
Press, 1983), pp. 251???266;
A. Vilenkin, Phys. Rev. D 27, 2848???2855 (1983); A. H. Guth, Phys. Rept.
333, 555-574 (2000), [astro-ph/0002156].
[insert comment worded by Quantum_Wave: The texts referred to in footnote six discuss the energy density of the universe and observations which point to a universe that is in eternal expansion. The universe tracks back to a hot dense state about one second after t=0 which implies an infinitely dense point origin or a singularity at the start of the universe.]
[7]
L. Rudnick, S. Brown and L. R. Williams, Astrophys.
J. 671, 40 (2007) [arXiv:0704.0908 [astro-ph]].
http://arxiv.org/abs/0704.0908
Astrophysics
Title:Extragalactic Radio Sources and the WMAP Cold Spot
Authors:Lawrence Rudnick, Shea Brown, Liliya R. Williams
(Submitted on 6 Apr 2007 (v1), last revised 3 Aug 2007 (this version, v2))
Abstract: We detect a dip of 20-45% in the surface brightness and number counts of NVSS sources smoothed to a few degrees at the location of the WMAP cold spot. The dip has structure on scales of approximately 1-10 degrees. Together with independent all-sky wavelet analyses, our results suggest that the dip in extragalactic brightness and number counts and the WMAP cold spot are physically related, i.e., that the coincidence is neither a statistical anomaly nor a WMAP foreground correction problem. If the cold spot does originate from structures at modest redshifts, as we suggest, then there is no remaining need for non-Gaussian processes at the last scattering surface of the CMB to explain the cold spot. The late integrated Sachs-Wolfe effect, already seen statistically for NVSS source counts, can now be seen to operate on a single region. To create the magnitude and angular size of the WMAP cold spot requires a ~140 Mpc radius completely empty void at z<=1 along this line of sight. This is far outside the current expectations of the concordance cosmology, and adds to the anomalies seen in the CMB.
Comments: revised version, ApJ, in press
Subjects: Astrophysics (astro-ph)
Journal reference: Astrophys.J.671:40-44,2007
DOI: 10.1086/522222
Cite as: arXiv:0704.0908v2 [astro-ph]
[8] Spergel et al.,[astro-ph/0603449],
http://xxx.lanl.gov/abs/astro-ph/0603449
Astrophysics
Title:Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
Authors
. N. Spergel, R. Bean, O. Doré, M. R. Nolta, C. L. Bennett, J. Dunkley, G. Hinshaw, N. Jarosik, E. Komatsu, L. Page, H. V. Peiris, L. Verde, M. Halpern, R. S. Hill, A. Kogut, M. Limon, S. S. Meyer, N. Odegard, G. S. Tucker, J. L. Weiland, E. Wollack, E. L. Wright
(Submitted on 19 Mar 2006 (v1), last revised 27 Feb 2007 (this version, v2))
Abstract: A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) fits not only the three year WMAP temperature and polarization data, but also small scale CMB data, light element abundances, large-scale structure observations, and the supernova luminosity/distance relationship. Using WMAP data only, the best fit values for cosmological parameters for the power-law flat LCDM model are (Omega_m h^2, Omega_b h^2, h, n_s, tau, sigma_8) = 0.1277+0.0080-0.0079, 0.02229+-0.00073, 0.732+0.031-0.032, 0.958+-0.016, 0.089+-0.030, 0.761+0.049-0.048). The three year data dramatically shrink the allowed volume in this six dimensional parameter space. Assuming that the primordial fluctuations are adiabatic with a power law spectrum, the WMAP data_alone_ require dark matter, and favor a spectral index that is significantly less than the Harrison-Zel'dovich-Peebles scale-invariant spectrum (n_s=1, r=0). Models that suppress large-scale power through a running spectral index or a large-scale cut-off in the power spectrum are a better fit to the WMAP and small scale CMB data than the power-law LCDM model; however, the improvement in the fit to the WMAP data is only Delta chi^2 = 3 for 1 extra degree of freedom. The combination of WMAP and other astronomical data yields significant constraints on the geometry of the universe, the equation of state of the dark energy, the gravitational wave energy density, and neutrino properties. Consistent with the predictions of simple inflationary theories, we detect no significant deviations from Gaussianity in the CMB maps.
Comments: 91 pgs, 28 figs. Accepted version of the 3-year paper as posted to this http URL in January 2007
Subjects: Astrophysics (astro-ph)
Journal reference: Astrophys.J.Suppl.170:377,2007
DOI: 10.1086/513700
Cite as: arXiv:astro-ph/0603449v2
And [8]
http://lambda.gsfc.nasa.gov/product/map (2006);
M. Tegmark et al., [arXiv:astro-ph/0608632].
http://xxx.lanl.gov/abs/astro-ph/0608632
Astrophysics
Title:Cosmological Constraints from the SDSS Luminous Red Galaxies
Authors:M Tegmark, D Eisenstein, M Strauss, D Weinberg, M Blanton, J Frieman, M Fukugita, J Gunn, A Hamilton, G Knapp, R Nichol, J Ostriker, N Padmanabhan, W Percival, D Schlegel, D Schneider, R Scoccimarro, U Seljak, H Seo, M Swanson, A Szalay, M Vogeley, J Yoo, I Zehavi, K Abazajian, S Anderson, J Annis, N Bahcall, B Bassett, A Berlind, J Brinkmann, T Budavari, F Castander, A Connolly, I Csabai, M Doi, D Finkbeiner, B Gillespie, K Glazebrook, G Hennessy, D Hogg, Z Ivezic, B Jain, D Johnston, S Kent, D Lamb, B Lee, H Lin, J Loveday, R Lupton, J Munn, K Pan, C Park, J Peoples, J Pier, A Pope, M Richmond, C Rockosi, R Scranton, R Sheth, A Stebbins, C Stoughton, I Szapudi, D Tucker, D Vanden Berk, B Yanny, D York
(Submitted on 30 Aug 2006 (v1), last revised 30 Oct 2006 (this version, v2))
Abstract: We measure the large-scale real-space power spectrum P(k) using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from the Wilkinson Microwave Anisotropy Probe (WMAP). We employ a matrix-based power spectrum estimation method using Pseudo-Karhunen-Loeve eigenmodes, producing uncorrelated minimum-variance measurements in 20 k-bands of both the clustering power and its anisotropy due to redshift-space distortions, with narrow and well-behaved window functions in the range 0.01h/Mpc < k < 0.2h/Mpc. Results from the LRG and main galaxy samples are consistent, with the former providing higher signal-to-noise. Our results are robust to omitting angular and radial density fluctuations and are consistent between different parts of the sky. They provide a striking confirmation of the predicted large-scale LCDM power spectrum.
Combining only SDSS LRG and WMAP data places robust constraints on many cosmological parameters that complement prior analyses of multiple data sets. The LRGs provide independent cross-checks on Om and the baryon fraction in good agreement with WMAP. Within the context of flat LCDM models, our LRG measurements complement WMAP by sharpening the constraints on the matter density, the neutrino density and the tensor amplitude by about a factor of two, giving Omega_m=0.24+-0.02 (1 sigma), sum m_nu < 0.9 eV (95%) and r<0.3 (95%). Baryon oscillations are clearly detected and provide a robust measurement of the comoving distance to the median survey redshift z=0.35 independent of curvature and dark energy properties. Within the LCDM framework, our power spectrum measurement improves the evidence for spatial flatness, sharpening the curvature constraint Omega_tot=1.05+-0.05 from WMAP alone to Omega_tot=1.003+-0.010. Assuming Omega_tot=1, the equation of state parameter is constrained to w=-0.94+-0.09, indicating the potential for more ambitious future LRG measurements to provide precision tests of the nature of dark energy. All these constraints are essentially independent of scales k>0.1h/Mpc and associated nonlinear complications, yet agree well with more aggressive published analyses where nonlinear modeling is crucial.
Comments: Matches accepted PRD version. SDSS data, likelihood code, Markov chains and ppt figures available at this http URL 36 journal pages, 25 figs. CosmoMC plugin at this http URL
Subjects: Astrophysics (astro-ph); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
Journal reference: Phys.Rev.D74:123507,2006
DOI: 10.1103/PhysRevD.74.123507
Cite as: arXiv:astro-ph/0608632v2
[9]
A. Kashlinsky, F. Atrio-Barandela, D. Kocevski and
H. Ebeling, galaxies: Astrophys. J. 691, 1479 (2009)
[arXiv:0809.3733 [astro-ph]],
http://arxiv.org/abs/0809.3733
Astrophysics
Title:A measurement of large-scale peculiar velocities of clusters of galaxies: technical details
Authors:A. Kashlinsky (GSFC), F. Atrio-Barandela (U of Salamanca), D. Kocevski (UC Davis), H. Ebeling (U of Hawaii)
(Submitted on 22 Sep 2008 (v1), last revised 4 Feb 2009 (this version, v2))
Abstract: This paper presents detailed analysis of large-scale peculiar motions derived from a sample of ~ 700 X-ray clusters and cosmic microwave background (CMB) data obtained with WMAP. We use the kinematic Sunyaev-Zeldovich (KSZ) effect combining it into a cumulative statistic which preserves the bulk motion component with the noise integrated down. Such statistic is the dipole of CMB temperature fluctuations evaluated over the pixels of the cluster catalog (Kashlinsky & Atrio-Barandela 2000). To remove the cosmological CMB fluctuations the maps are Wiener-filtered in each of the eight WMAP channels (Q, V, W) which have negligible foreground component. Our findings are as follows: The thermal SZ (TSZ) component of the clusters is described well by the Navarro-Frenk-White profile expected if the hot gas traces the dark matter in the cluster potential wells. Such gas has X-ray temperature decreasing rapidly towards the cluster outskirts, which we demonstrate results in the decrease of the TSZ component as the aperture is increased to encompass the cluster outskirts. We then detect a statistically significant dipole in the CMB pixels at cluster positions. Arising exclusively at the cluster pixels this dipole cannot originate from the foreground or instrument noise emissions and must be produced by the CMB photons which interacted with the hot intracluster gas via the SZ effect. The dipole remains as the monopole component, due to the TSZ effect, vanishes within the small statistical noise out to the maximal aperture where we still detect the TSZ component. We demonstrate with simulations that the mask and cross-talk effects are small for our catalog and contribute negligibly to the measurements. The measured dipole thus arises from the KSZ effect produced by the coherent large scale bulk flow motion.
Comments: Minor changes to match the published version - Ap.J., 1 Feb 2009 issue
Subjects: Astrophysics (astro-ph)
Journal reference: Astrophys.J.691:1479-1493,2009
DOI: 10.1088/0004-637X/691/2/1479
Cite as: arXiv:0809.3733v2 [astro-ph]
And [9]
Astrophys. J. 686, L49
(2009) [arXiv:0809.3734 [astro-ph]]
http://arxiv.org/abs/0809.3734
Astrophysics
Title:A measurement of large-scale peculiar velocities of clusters of galaxies: results and cosmological implications
Authors:A. Kashlinsky (GSFC), F. Atrio-Barandela (U of Salamanca), D. Kocevski (UC Davis), H. Ebeling (U of Hawaii)
(Submitted on 22 Sep 2008)
Abstract: Peculiar velocities of clusters of galaxies can be measured by studying the fluctuations in the cosmic microwave background (CMB) generated by the scattering of the microwave photons by the hot X-ray emitting gas inside clusters. While for individual clusters such measurements result in large errors, a large statistical sample of clusters allows one to study cumulative quantities dominated by the overall bulk flow of the sample with the statistical errors integrating down. We present results from such a measurement using the largest all-sky X-ray cluster catalog combined to date and the 3-year WMAP CMB data. We find a strong and coherent bulk flow on scales out to at least > 300 h^{-1} Mpc, the limit of our catalog. This flow is difficult to explain by gravitational evolution within the framework of the concordance LCDM model and may be indicative of the tilt exerted across the entire current horizon by far-away pre-inflationary inhomogeneities.
Comments: Ap.J. (Letters), in press. 20 Oct issue (Vol. 686)
Subjects: Astrophysics (astro-ph)
Journal reference: Astrophys.J.686:L49-L52,2009
DOI: 10.1086/592947
Cite as: arXiv:0809.3734v1 [astro-ph]
And [9]
Mon. Not. Roy.
Astron. Soc. 407, 2328 (2010) [arXiv:0911.5516
[astro-ph.CO]];
http://arxiv.org/abs/0911.5516
Astrophysics > Cosmology and Extragalactic Astrophysics
Title:Cosmic Flows on 100 Mpc/h Scales: Standardized Minimum Variance Bulk Flow, Shear and Octupole Moments
Authors:Hume A. Feldman (Kansas), Richard Watkins (Willamette), Michael J. Hudson (Waterloo)
(Submitted on 29 Nov 2009 (v1), last revised 25 Jun 2010 (this version, v2))
Abstract: The low order moments, such as the bulk flow and shear, of the large scale peculiar velocity field are sensitive probes of the matter density fluctuations on very large scales. In practice, however, peculiar velocity surveys are usually sparse and noisy, which can lead to the aliasing of small scale power into what is meant to be a probe of the largest scales. Previously, we developed an optimal ``minimum variance'' (MV) weighting scheme, designed to overcome this problem by minimizing the difference between the measured bulk flow (BF) and that which would be measured by an ideal survey. Here we extend this MV analysis to include the shear and octupole moments, which are designed to have almost no correlations between them so that they are virtually orthogonal. We apply this MV analysis to a compilation of all major peculiar velocity surveys, consisting of 4536 measurements. Our estimate of the BF on scales of ~ 100 Mpc/h has a magnitude of |v|= 416 +/- 78 km/s towards Galactic l = 282 degree +/- 11 degree and b = 6 degree +/- 6 degree. This result is in disagreement with LCDM with WMAP5 cosmological parameters at a high confidence level, but is in good agreement with our previous MV result without an orthogonality constraint, showing that the shear and octupole moments did not contaminate the previous BF measurement. The shear and octupole moments are consistent with WMAP5 power spectrum, although the measurement noise is larger for these moments than for the BF. The relatively low shear moments suggest that the sources responsible for the BF are at large distances.
Comments: 13 Pages, 7 figures, 4 tables. Some changes to reflect the published version
Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO)
Journal reference: Mon.Not.Roy.Astron.Soc.407:2328-2338,2010
DOI: 10.1111/j.1365-2966.2010.17052.x
Cite as: arXiv:0911.5516v2 [astro-ph.CO]
And [9]
Mon. Not. Roy. Astron. Soc. 392, 743
(2009) [arXiv:0809.4041 [astro-ph]].
http://arxiv.org/abs/0809.4041
Astrophysics
Title:Consistently Large Cosmic Flows on Scales of 100 Mpc/h: a Challenge for the Standard LCDM Cosmology
Authors:Richard Watkins (Willamette), Hume A. Feldman (Kansas), Michael J. Hudson (Waterloo)
(Submitted on 23 Sep 2008 (v1), last revised 27 Nov 2008 (this version, v3))
Abstract: Peculiar velocity surveys have non-uniform spatial distributions of tracers, so that the bulk flow estimated from them does not correspond to that of a simple volume such as a sphere. Thus bulk flow estimates are generally not strictly comparable between surveys, even those whose effective depths are similar. In addition, the sparseness of typical surveys can lead to aliasing of small scale power into what is meant to be a probe of the largest scales. Here we introduce a new method of calculating bulk flow moments where velocities are weighted to give an optimal estimate of the bulk flow of an idealized survey, with the variance of the difference between the estimate and the actual flow being minimized. These "minimum variance" estimates can be designed to estimate the bulk flow on a particular scale with minimal sensitivity to small scale power, and are comparable between surveys. We compile all major peculiar velocity surveys and apply this new method to them. We find that most surveys we studied are highly consistent with each other. Taken together the data suggest that the bulk flow within a Gaussian window of radius 50 Mpc/h is 407 km/s toward l=287 and b=8. The large-scale bulk motion is consistent with predictions from the local density field. This indicates that there are significant density fluctuations on very large scales. A flow of this amplitude on such a large scale is not expected in the WMAP5-normalized LCDM cosmology, for which the predicted one-dimensional r.m.s. velocity is ~110 km/s. The large amplitude of the observed bulk flow favors the upper values of the WMAP5 error-ellipse, but even the point at the top of the WMAP5 95% confidence ellipse predicts a bulk flow which is too low compared to that observed at >98% confidence level.
Comments: 19 Pages, 7 Figures, MNRAS in Press. Added some references and text to reflect post proofs manuscript
Subjects: Astrophysics (astro-ph)
Journal reference: Mon.Not.Roy.Astron.Soc.392:743-756,2009
DOI: 10.1111/j.1365-2966.2008.14089.x
Cite as: arXiv:0809.4041v3 [astro-ph]
[10]
A. Aguirre, M. C. Johnson and A. Shomer, Phys.
Rev. D 76, 063509 (2007) [arXiv:0704.3473 [hep-
th]
http://arxiv.org/abs/0704.3473
High Energy Physics - Theory
Title:Towards observable signatures of other bubble universes
Authors:Anthony Aguirre, Matthew C Johnson, Assaf Shomer
(Submitted on 26 Apr 2007 (v1), last revised 25 Jul 2007 (this version, v3))
Abstract: We evaluate the possibility of observable effects arising from collisions between vacuum bubbles in a universe undergoing false-vacuum eternal inflation. Contrary to conventional wisdom, we find that under certain assumptions most positions inside a bubble should have access to a large number of collision events. We calculate the expected number and angular size distribution of such collisions on an observer's "sky," finding that for typical observers the distribution is anisotropic and includes many bubbles, each of which will affect the majority of the observer's sky. After a qualitative discussion of the physics involved in collisions between arbitrary bubbles, we evaluate the implications of our results, and outline possible detectable effects. In an optimistic sense, then, the present paper constitutes a first step in an assessment of the possible effects of other bubble universes on the cosmic microwave background and other observables.
Comments: 17 PRD-style pages including 13 embedded figures. Minor corrections to figures 4 and 7 and added discussion in Sec. III.E.2 and V
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc)
Journal reference: Phys.Rev.D76:063509,2007
DOI: 10.1103/PhysRevD.76.063509
Cite as: arXiv:0704.3473v3 [hep-th]
And [10]
A. Aguirre and M. C. Johnson, Phys. Rev. D 77,
123536 (2008) [arXiv:0712.3038 [hep-th]].
http://arxiv.org/abs/0712.3038
High Energy Physics - Theory
Title:Towards observable signatures of other bubble universes II: Exact solutions for thin-wall bubble collisions
Authors:Anthony Aguirre, Matthew C Johnson
(Submitted on 18 Dec 2007 (v1), last revised 22 Jul 2008 (this version, v4))
Abstract: We assess the effects of a collision between two vacuum bubbles in the thin-wall limit. After describing the outcome of a generic collision possessing the expected hyperbolic symmetry, we focus on collisions experienced by a bubble containing positive vacuum energy, which could in principle contain our observable universe. We provide criteria governing whether the post-collision domain wall accelerates towards or away from this "observation" bubble, and discuss the implications for observers located at various positions inside of the bubble. Then, we identify the class of solutions which have minimal impact on the interior of the observation bubble, and derive a simple formula for the energy density of a shell of radiation emitted from such a collision. In the context of a universe undergoing false vacuum eternal inflation, these solutions are perhaps the most promising candidates for collisions that could exist within our past light cone, and therefore in principle be observable.
Comments: 18 PRD-style pages, 12 figures. Added appendix on the expected number of collisions, added references, minor correction to Appendix C, conclusions unchanged. Replaced to match published version
Subjects: High Energy Physics - Theory (hep-th); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc)
Journal reference: Phys.Rev.D77:123536,2008
DOI: 10.1103/PhysRevD.77.123536
Cite as: arXiv:0712.3038v4 [hep-th]
[11]
J. Garriga, A. H. Guth and A. Vilenkin, Phys. Rev.
D 76, 123512 (2007) [arXiv:hep-th/0612242].
http://arxiv.org/abs/hep-th/0612242
High Energy Physics - Theory
Title:Eternal inflation, bubble collisions, and the persistence of memory
Authors:Jaume Garriga (Barcelona), Alan H. Guth (MIT), Alexander Vilenkin (Tufts)
(Submitted on 21 Dec 2006)
Abstract: A ``bubble universe'' nucleating in an eternally inflating false vacuum will experience, in the course of its expansion, collisions with an infinite number of other bubbles. In an idealized model, we calculate the rate of collisions around an observer inside a given reference bubble. We show that the collision rate violates both the homogeneity and the isotropy of the bubble universe. Each bubble has a center which can be related to ``the beginning of inflation'' in the parent false vacuum, and any observer not at the center will see an anisotropic bubble collision rate that peaks in the outward direction. Surprisingly, this memory of the onset of inflation persists no matter how much time elapses before the nucleation of the reference bubble.
Comments: 27 pages, 3 figures
Subjects: High Energy Physics - Theory (hep-th)
Journal reference: Phys.Rev.D76:123512,2007
DOI: 10.1103/PhysRevD.76.123512
Report number: MIT-CTP-3800
Cite as: arXiv:hep-th/0612242v1
[12]
A. Borde, A. H. Guth and A. Vilenkin, Phys. Rev.
Lett. 90, 151301 (2003) [arXiv:gr-qc/0110012].
http://arxiv.org/abs/gr-qc/0110012
General Relativity and Quantum Cosmology
Title:Inflationary spacetimes are not past-complete
Authors:Arvind Borde, Alan H. Guth, Alexander Vilenkin
(Submitted on 1 Oct 2001 (v1), last revised 14 Jan 2003 (this version, v2))
Abstract: Many inflating spacetimes are likely to violate the weak energy condition, a key assumption of singularity theorems. Here we offer a simple kinematical argument, requiring no energy condition, that a cosmological model which is inflating -- or just expanding sufficiently fast -- must be incomplete in null and timelike past directions. Specifically, we obtain a bound on the integral of the Hubble parameter over a past-directed timelike or null geodesic. Thus inflationary models require physics other than inflation to describe the past boundary of the inflating region of spacetime.
Comments: We improve the basic argument to apply to a wider class of spacetimes, use a better title and add a discussion of cyclic models. 4 pages, 1 figure, RevTeX
Subjects: General Relativity and Quantum Cosmology (gr-qc)
Journal reference: Phys.Rev.Lett. 90 (2003) 151301
DOI: 10.1103/PhysRevLett.90.151301
Report number: MIT-CTP-3183
Cite as: arXiv:gr-qc/0110012v2
[13]
A. Borde and A. Vilenkin, Phys. Rev. Lett. 72, 3305
(1994) [arXiv:gr-qc/9312022].
http://arxiv.org/abs/gr-qc/9312022
General Relativity and Quantum Cosmology
Title:Eternal inflation and the initial singularity
Authors:Arvind Borde, Alexander Vilenkin
(Submitted on 15 Dec 1993)
Abstract: It is shown that a physically reasonable spacetime that is eternally inflating to the future must possess an initial singularity.
Comments: 11 pages, Tufts University cosmology preprint
Subjects: General Relativity and Quantum Cosmology (gr-qc)
Journal reference: Phys.Rev.Lett.72:3305-3309,1994
DOI: 10.1103/PhysRevLett.72.3305
Cite as: arXiv:gr-qc/9312022v1
[14]
A. Borde and A. Vilenkin, Int. J. Mod. Phys. D 5,
813 (1996) [arXiv:gr-qc/9612036].
http://arxiv.org/abs/gr-qc/9612036
General Relativity and Quantum Cosmology
Title:Singularities in Inflationary Cosmology: A Review
Authors:Arvind Borde, Alexander Vilenkin
(Submitted on 15 Dec 1996)
Abstract: We review here some recent results that show that inflationary cosmological models must contain initial singularities. We also present a new singularity theorem. The question of the initial singularity re-emerges in inflationary cosmology because inflation is known to be generically future-eternal. It is natural to ask, therefore, if inflationary models can be continued into the infinite past in a non-singular way. The results that we discuss show that the answer to the question is ``no.'' This means that we cannot use inflation as a way of avoiding the question of the birth of the Universe. We also argue that our new theorem suggests - in a sense that we explain in the paper - that the Universe cannot be infinitely old.
Comments: Plain TeX. Twelve pages, five figures (that will automatically appear if you use "dvips" to print the file)
Subjects: General Relativity and Quantum Cosmology (gr-qc)
Journal reference: Int.J.Mod.Phys. D5 (1996) 813-824
DOI: 10.1142/S0218271896000497
Cite as: arXiv:gr-qc/9612036v1
[15]
C. Carvalho and M. Bucher, Phys. Lett. B 546, 8
(2002) [arXiv:hep-ph/0207275].
http://arxiv.org/abs/hep-ph/0207275
High Energy Physics - Phenomenology
Title:Separation Distribution of Vacuum Bubbles in de Sitter Space
Authors:Carla Carvalho, Martin Bucher (DAMTP, University of Cambridge)
(Submitted on 23 Jul 2002)
Abstract: We compute the probability distribution of the invariant separation between nucleation centers of colliding true vacuum bubbles arising from the decay of a false de Sitter space vacuum. We find that even in the limit of a very small nucleation rate per unit Hubble volume the production of widely separated bubble pairs is suppressed. This distribution is of particular relevance for the recently proposed ``colliding bubble braneworld'' scenario, in which the value of Omega_k (the contribution of negative spatial curvature to the cosmological density parameter) is determined by the invariant separation of the colliding bubble pair. We also consider the probability of a collision with a `third' bubble.
Comments: 15 pages REVTEX, 2 Postscript figures
Subjects: High Energy Physics - Phenomenology (hep-ph)
Journal reference: Phys.Lett. B546 (2002) 8-18
DOI: 10.1016/S0370-2693(02)02662-X
Cite as: arXiv:hep-ph/0207275v1
[16]
J. R. Gott, T. S. Statler, Phys. Lett. B136, 157-161
(1984).
http://usparc.ihep.su/spires/find/hep/www?irn=1247450
Constraints On The Formation Of Bubble Universes.
J.R. Gott, T.S. Statler (Princeton U.) . 1984.
Published in Phys.Lett.B136:157-161,1984.
[17]
M. Bucher, A. S. Goldhaber and N. Turok, Phys. Rev.
D 52, 3314 (1995) [arXiv:hep-ph/9411206];
http://arxiv.org/abs/hep-ph/9411206
High Energy Physics - Phenomenology
Title:An Open Universe from Inflation
Authors:M. Bucher (Princeton U.), A.S. Goldhaber (SUNYSB), N. Turok
(Submitted on 2 Nov 1994 (v1), last revised 21 Mar 1995 (this version, v6))
Abstract: We present a natural scenario for obtaining an open universe ($\Omega _0<1$) through inflation. In this scenario, there are two epochs of inflationary expansion---an epoch of `old inflation,' during which the inflaton field is stuck in a false vacuum, followed by an epoch of `new inflation,' during which the inflaton field slowly rolls toward its true minimum. During the first epoch, inflation solves the smoothness and horizon problems. Then an open universe (with negative spatial curvature) is created by the nucleation of a single bubble. In effect $\Omega$ is instantaneously `reset' to zero. During the subsequent `new' inflation $\Omega$ rises toward unity. The value of $\Omega$ today is calculable in terms of the parameters of the potential, and we show that obtaining values significantly different from zero or unity (though within the range $0<\Omega <1$) does not require significant fine tuning. We compute the spectrum of density perturbations by evolving the Bunch-Davies vacuum modes across the bubble wall into its interior.
Comments: 60 pages + 3 figures. Uses PHYZZX macro package. In this revised version we replace the numerical results of the previous version with exact analytic solutions. Some minor mistakes are corrected and there is some new material.
Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)
Journal reference: Phys.Rev. D52 (1995) 3314-3337
DOI: 10.1103/PhysRevD.52.3314
Cite as: arXiv:hep-ph/9411206v6
And [17]
A. S. Goncharov, A. D. Linde and V. F. Mukhanov, Int. J. Mod.
Phys. A 2, 561 (1987).
http://scholar.google.com/scholar?q...l+of+Modern+Physics+A&as_ylo=1987&as_yhi=1987
The global structure of the inflationary universe
AS Goncharov, AD Linde… - … Journal of Modern Physics …, 1987 - worldscinet.com
In this article we give a review of recent results concerning the global structure of the inflationary
universe, which have been obtained within stochastic approach to inflation. It is shown in particular
that the evolution of the universe in the chaotic inflation scenario has no end and may ...
Cited by 276 - Related articles - All 7 versions
[18]
A. D. Linde, Phys. Rev. D 59, 023503 (1999)
[arXiv:hep-ph/9807493].
http://arxiv.org/abs/hep-ph/9807493
High Energy Physics - Phenomenology
Title:A Toy Model for Open Inflation
Authors:Andrei Linde
(Submitted on 27 Jul 1998 (v1), last revised 14 Aug 1998 (this version, v3))
Abstract: The open inflation scenario based on the theory of bubble formation in the models of a single scalar field suffered from a fatal defect. In all the versions of this scenario known so far, the Coleman-De Luccia instantons describing the creation of an open universe did not exist. We propose a simple one-field model where the CDL instanton does exist and the open inflation scenario can be realized.
Comments: 7 pages, 4 figures, revtex, a discussion of density perturbations is extended
Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
Journal reference: Phys.Rev.D59:023503,1999
DOI: 10.1103/PhysRevD.59.023503
Report number: SU-ITP-98-45
Cite as: arXiv:hep-ph/9807493v3
[19]
T. Jacobson, D. Mattingly, Phys. Rev. D64, 024028
(2001). [gr-qc/0007031].
http://arxiv.org/abs/gr-qc/0007031
General Relativity and Quantum Cosmology
Title:Gravity with a dynamical preferred frame
Authors:Ted Jacobson, David Mattingly
(Submitted on 14 Jul 2000 (v1), last revised 2 Jun 2001 (this version, v4))
Abstract: We study a generally covariant model in which local Lorentz invariance is broken "spontaneously" by a dynamical unit timelike vector field $u^a$---the "aether". Such a model makes it possible to study the gravitational and cosmological consequences of preferred frame effects, such as ``variable speed of light" or high frequency dispersion, while preserving a generally covariant metric theory of gravity. In this paper we restrict attention to an action for an effective theory of the aether which involves only the antisymmetrized derivative $\nabla_{[a}u_{b]}$. Without matter this theory is equivalent to a sector of the Einstein-Maxwell-charged dust system. The aether has two massless transverse excitations, and the solutions of the model include all vacuum solutions of general relativity (as well as other solutions). However, the aether generally develops gradient singularities which signal a breakdown of this effective theory. Including the symmetrized derivative in the action for the aether field may cure this problem.
Comments: 9 pages; title changed, references added, relation to prior work of Gasperini discussed, errors in scalar field stress tensor corrected, various minor changes to Introduction; Final version to be published in PRD: relation to prior work of Kostelecky and Samuel spelled out in detail, clarifications and sign errors corrected in section on linearized solutions, references added; Really final version: (u^m \nabla_m u^a)^2 term added to most general Lagrangian eqn.(3.1)
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
Journal reference: Phys.Rev. D64 (2001) 024028
DOI: 10.1103/PhysRevD.64.024028
Cite as: arXiv:gr-qc/0007031v4
[20]
P.W.Anderson, Physical Review 109, 1492 (1958).
http://webcache.googleusercontent.c...d=1&hl=en&ct=clnk&gl=us&source=www.google.com
Why is disorder important in metals?
Disorder, even when weak, makes a qualitative di erence to the transport properties
of metals. The Boltzmann description of charges scattering o impurities predicts a
residual resistivity that increases with disorder. This simple picture is insu cient to
explain experimentally observed behaviour even for weak disorder. When disorder is
weak, deviations are seen from Ohm’s law in the sample-size dependence of resistance.
These deviations are especially remarkable in one and two dimensions.
Physically, repeated scattering of an electron from impurities causes the electron wave-
function to quantum-interfere with itself. Such interference may even cause it to become
localised which leads to an exponential increase of resistance with system size. This is
completely unexpected in the semi-classical treatment of electrical conduction.
A phenomenon analogous to localisation in metals is observed commonly: a stack of
transparencies is practically opaque while individual sheets are transparent.
5 Lecture notes prepared by Vikram Tripathi
6 Di cult reading.
7 Also known as the Gang of Four.
8 Perturbation theory, diagrammatic analysis.
9 Hard to nd. Can read LK above instead
[21]
Blank
[22] A. H. Guth, J. Phys. A 40, 6811 (2007)
[arXiv:hep-th/0702178].
http://arxiv.org/abs/hep-th/0702178
High Energy Physics - Theory
Title:Eternal inflation and its implications
Authors:Alan H. Guth
(Submitted on 22 Feb 2007)
Abstract: I summarize the arguments that strongly suggest that our universe is the product of inflation. The mechanisms that lead to eternal inflation in both new and chaotic models are described. Although the infinity of pocket universes produced by eternal inflation are unobservable, it is argued that eternal inflation has real consequences in terms of the way that predictions are extracted from theoretical models. The ambiguities in defining probabilities in eternally inflating spacetimes are reviewed, with emphasis on the youngness paradox that results from a synchronous gauge regularization technique. Although inflation is generically eternal into the future, it is not eternal into the past: it can be proven under reasonable assumptions that the inflating region must be incomplete in past directions, so some physics other than inflation is needed to describe the past boundary of the inflating region.
Comments: 21 pages, 5 figures. Talk presented at the "2nd International Conference on Quantum Theories and Renormalization Group in Gravity and Cosmology (IRGAC 2006)," Barcelona, Spain, 11-15 July 2006, to be published in J. Phys. A
Subjects: High Energy Physics - Theory (hep-th)
Journal reference: J.Phys.A40:6811-6826,2007
DOI: 10.1088/1751-8113/40/25/S25
Report number: MIT-CTP-3811
Cite as: arXiv:hep-th/0702178v1
[23] We thank the referee for raising this point