Download presentation

Presentation is loading. Please wait.

Published byBlaise Secker Modified about 1 year ago

1
L. Perivolaropoulos http://leandros.physics.uoi.gr Department of Physics University of Ioannina Open page Collaborators: I. Antoniou (Ioannina) J. Bueno-Sanchez (Madrid) J. Grande (Barcelona) S. Nesseris (Madrid) A. Mariano (Lecce)

2
The consistency level of ΛCDM with geometrical data probes has been increasing with time during the last decade. There are some puzzling conflicts between ΛCDM predictions and dynamical data probes (bulk flows, alignment and magnitude of low CMB multipoles, Fine Structure Constant Dipole, Dark energy Dipole) Most of these puzzles are related to the existence of preferred anisotropy axes which appear to be surprisingly close to each other! The simplest mechanism that can give rise to a cosmological preferred axis is based on an off-center observer in a spherical energy inhomogeneity (dark matter or dark energy) Topological Quintessence is a simple physical mechanism that can give rise to a Hubble scale dark energy inhomogeneity.

3
Good Agreement with Geometric Probes! SNLS ESSENCE GOLD06 UNION CONSTITUTION WMAP5+SDSS5 WMAP7+SDSS7 UNION2 J. C. Bueno Sanchez, S. Nesseris, LP, JCAP 0911:029,2009, 0908.2636

4
Large Scale Velocity Flows - Predicted: On scale larger than 50 h -1 Mpc Dipole Flows of 110km/sec or less. - Observed: Dipole Flows of more than 400km/sec on scales 50 h -1 Mpc or larger. - Probability of Consistency: 1% Anisotropy of Cosmic Accelerating Expansion - Predicted: Isotropic Rate of Accelerating Expansion - Observed: SnIa data show hints for an anisotropic acceleration fit by a Dipole - Probability of Consistency: 5% From LP, 0811.4684, I. Antoniou, LP, JCAP 1012:012, 2010, arxiv:1007.4347 R. Watkins et. al., Mon.Not.Roy.Astron.Soc.392:743-756,2009, 0809.4041. A. Kashlinsky et. al. Astrophys.J.686:L49-L52,2009 arXiv:0809.3734 A. Mariano, LP,, Phys.Rev. D86 (2012) 083517, Alignment of Low CMB Spectrum Multipoles - Predicted: Multipole components of CMB map should be uncorrelated. - Observed: l=2 and l=3 CMB map components are unlikely planar and close to each other. - Probability of Consistency: 1% Cosmic Spatial Dependence of the Fine Structure Constant - Predicted: The value of the Fine Structure Constant is Space-Time Independent. - Observed : There is a cosmic spatial dependence well fit by a Dipole with δα/α~10 -5 - Probability of Consistency: 0.01% Webb et. al.., Phys. Rev. Lett. 107, 191101 (2011) M. Tegmark et. al., PRD 68, 123523 (2003), Copi et. al. Adv.Astron.2010:847541,2010.

5
All four puzzles for ΛCDM are related to the existence of a preferred axis A. Kashlinsky et. al. Astrophys.J.686:L49- L52,2009 arXiv:0809.3734 Quadrupole component of CMB map Octopole component of CMB mapDipole component of CMB map M. Tegmark et. al., PRD 68, 123523 (2003), Copi et. al. Adv.Astron.2010:847541,2010. Dark Velocity Flow ΛCDM prediction Observed Flow by the kSZ effect

6
Quasar Absorption Spectra: From absorption lines we can find both the absorber redshift and the value of the fine structure constant α=e 2 /hc at the time of absorption. KEK+VLT data: Webb et. al. Phys. Rev. Lett. 107, 191101 (2011)

7
King et. al., MNRAS,422, 3370, (2012) Dipole+Monopole Maximum Likelihood Fit: 295 absorbers 4 parameters l= 320 o, b=-11 o larger α A. Mariano, LP,, Phys.Rev. D86 (2012) 083517,

8
brighter SnIa smaller μ l= 309 o, b=-15 o

9
Maximize Temperature Difference between opposite pixels at various resolutions: Maximum Temperature Asymmetry Axis Correlation with the Quadrupole-Octopole Plane WMAP7 ILC Maps A. Mariano, L.P., arxiv:arXiv:1211.59155

10
Dark Flow Direction (3σ) Watkins et. al. arxiv: 0809.4041, Kashlinsky et. al. arxiv: 0809.3734 WMAP7 ILC Map – Maximum Temperature Asymmetry (1.5 σ) 15 o Pixel Pair (A. Mariano, LP, arXiv:1211.5915) α Dipole (4σ) Webb et. al., Phys. Rev. Lett. 107, 191101 (2011) Q1: How anomalous is this coincidence?Q2: Is there a physical model that can predict this coincidence Dark Energy Dipole (2σ) A. Mariano, LP,, Phys.Rev. D86 (2012) 083517.

11
A1: The probability that the combined quasar absorber and SnIa data are obtained in the context of a homogeneous and isotropic cosmology is less than one part in 10 6. A2: There is a simple physical model based on a Hubble scale topological defect non-minimally coupled to electromagnetism that has the potential to explain the observed aligned dipoles. Q1: What is the probability to produce the observed combination of just the two dipoles in a homogeneous-isotropic cosmological model? Q2: What physical model has the potential to predict the existence of the above combined dipoles?

12
Probability to obtain as large (or larger) dipole magnitudes with the observed alignment in an isotropic cosmological model: The fraction of isotropic Monte Carlo Keck+VLT datasets that can reproduce the obverved dipole magnitude is less than 0.01% The fraction of isotropic Monte Carlo Union2 datasets that can reproduce the obverved dipole magnitude and the observed alignment with Keck+VLT dipole is less than 1% 0.01% x 1% = 0.0001% 0.01% 1% Monte-Carlo of Isotropic quasar absorber datasets (quasar positions fixed) Monte-Carlo of Isotropic SnIa Uniot2 datasets (SnIa positions fixed)

13
Anisotropic dark energy equation of state (eg vector fields) (T. Koivisto and D. Mota (2006), R. Battye and A. Moss (2009)) Fundamentaly Modified Cosmic Topology or Geometry (rotating universe, horizon scale compact dimension, non-commutative geometry etc) (J. P. Luminet (2008), P. Bielewicz and A. Riazuelo (2008), E. Akofor, A. P. Balachandran, S. G. Jo, A. Joseph,B. A. Qureshi (2008), T. S. Koivisto, D. F. Mota, M. Quartin and T. G. Zlosnik (2010)) Statistically Anisotropic Primordial Perturbations (eg vector field inflation) (A. R. Pullen and M. Kamionkowski (2007), L. Ackerman, S. M. Carroll and M. B. Wise (2007), K. Dimopoulos, M. Karciauskas, D. H. Lyth and Y. Ro-driguez (2009)) Horizon Scale Primordial Magnetic Field. (T. Kahniashvili, G. Lavrelashvili and B. Ratra (2008), L. Campanelli (2009), J. Kim and P. Naselsky (2009)) Horizon Scale Dark Matter or Dark Energy Perturbations (eg few Gpc void) (J. Garcia-Bellido and T. Haugboelle (2008), P. Dunsby, N. Goheer, B. Osano and J. P. Uzan (2010), T. Biswas, A. Notari and W. Valkenburg (2010))

14
Faster expansion rate at low redshifts (local space equivalent to recent times) Local spherical underdensity of matter (Void), no dark energy Central Observer Apparent Acceleration

15
Faster expansion rate at low redshifts (local space equivalent to recent times) Local spherical underdensity of matter (Void) Observer Preferred Direction

16
Metric: Cosmological Equation: Geodesics: Luminosity Distance: FRW limit: M

17
Advantages: 1. No need for dark energy. 2. Natural Preferred Axis. 3. Coincidence Problem J. Grande, L.P., Phys. Rev. D 84, 023514 (2011). Problems: 1. No simple mechanism to create such large voids. 2. Off-Center Observer produces too large CMB Dipole. 3. Worse Fit than LCDM. 4. Ruled out by kSZ – CMB (Zhang and Stebbins, Phys.Rev.Lett. 107 (2011) 041301 )

18
Coincidence Problem: Why Now? Time Dependent Dark Energy Alternatively: Why Here? Inhomogeneous Dark Energy Standard Model (ΛCDM): 1. Homogeneous - Isotropic Dark and Baryonic Matter. 2. Homogeneous-Isotropic-Constant Dark Energy (Cosmological Constant) 3. General Relativity Consider Because: 1. New generic generalization of ΛCDM (breaks homogeneity of dark energy). Includes ΛCDM as special case. 2.Natural emergence of preferred axis (off – center observers) 3.Well defined physical mechanism (topological quintessence with Hubble scale global monopoles). J. Grande, L.P., Phys. Rev. D 84, 023514 (2011). J. B. Sanchez, LP, Phys.Rev. D84 (2011) 123516

19
Global Monopole with Hubble scale Core General Metric with Spherical Symmetry: Energy – Momentum Tensor:

20
Global Monopole: Field Direction in Space and Energy Density Off-center Observer Variation of expansion rate due to dark energy density variation Variation of α?

21
Global Monopole Configuration: Non-minimally coupled scalar field Fine Structure Constant: Fine Structure Constant Spatial Variation:

22
Global Monopole: Field Direction in Space and Energy Density Off-center Observer Variation of α due to field variationVariation of expansion rate due to dark energy density variation

23
Monopole Core Scale: Potential Energy Density at the Core: Approximate Cosmic Evolution at the Core: Approximate Cosmic Evolution away from the Core: Physical Requirements: Cosmological Scale Core Core Density similar as present matter density J. B. Sanchez, LP,, Phys.Rev. D84 (2011) 123516

24
Initial-Boundary Conditions Energy-Momentum Conservation Static Monopole Profile (Φ=f(r) ) Homogeneous, Flat Matter Dominated (A=B=1)

25
Does the Monopole Energy Density Eventually Dominate over matter in the Monopole Core? Does the possible domination lead to accelerating expansion in the monopole core? Can this cosmological expansion in the core fit the cosmological data?

26
1.Monopole energy density slowly shrinks and dominates at late times in the core. 2.Matter develops underdensity at the core.

27
η=0.1 M pl η=0.6 M pl η=0.1 M pl η=0.6 M pl Accelerating Expansion at the core. r=0 r=0.5 r=5

28
Cosmological Equation: Isocurvature Profiles (Flat): LTB Metric: Energy Momentum:

29
Geodesics: Luminosity Distance: ΛCDM limit Ruled out region at 3σ Union 2 χ 2 contours

30
Geodesics: Luminosity Distance: J. Grande, L.P., Phys. Rev. D 84, 023514 (2011).

31
Geodesics Luminosity Distance

32
Some improvement in quality of fit over ΛCDM. Increased for large r 0. Copernican Principle Respected (r obs /r 0 as large as 0.7). Minimized with respect to (l c,b c )

33
Last Scattering Surface Dipole a 10 (r obs,r 0 ) from geodesics (z to t dec )

34
Problem with Copernican Principle rapidly improves for large r 0 Expected to be alleviated for r 0 ~r ls

36
Early hints for deviation from the cosmological principle and statistical isotropy are being accumulated. This appears to be one of the most likely directions which may lead to new fundamental physics in the coming years. The simplest mechanism that can give rise to a cosmological preferred axis is based on an off-center observer in a spherical energy inhomogeneity (dark matter of dark energy) Such a mechanism can give rise to aligned CMB multipoles, large scale velocity flows and Fine Structure Constant Dipole. Other interesting effects may occur (quasar polarization alignment etc). Topological Quintessence constitutes a physical mechanism to produce Hubble scale dark energy inhomogeneities.

37
Is there a physical model that predicts the existence of such aligned dipoles? A. Mariano, L.P., Phys. Rev. D (to appear) arxiv:1206.4055 J. B. Sanchez, LP, Phys.Rev. D84 (2011) 123516 arxix:1110.2587 J. Grande, L.P., Phys. Rev. D 84, 023514 (2011).

38
Quasar Absorption lines shift in different ways as we change α : x 10 -5 α =0.9 α 0 α=0.5 α 0 α = α 0 Absorption lines due to various atoms and ions x 10 -5 Flambaum et. al. Phys. Rev. Lett. 82, 888 (1999)] Webb et al. [Phys. Rev. Lett. 87, 091301 (2001) Northern hemisphere data Keck Tescope in Hawaii Many Multiplet Method: Use several absorption lines (iron and magnesium) simultaneously to determine α

39
Keck Telescopes in Hawaii (North)VLT in Chile (South) Other study of Many Multiplet Method (VLT): Webb et. al. Phys. Rev. Lett. 107, 191101 (2011) King et. al., MNRAS,422, 3370, (2012) (23 absorbers, underestimated errors) 295 absorbers

40
Oklo natural reactor bounds From T. Chiba, arxiv: 1111.0092

41
Random number from Gaussian probability distribution 10 4 Isotropic Monte Carlo Keck+VLT samples: None had as large a dipole magnitude as the observed!

Similar presentations

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google