Dark Energy and Void Evolution Dark Energy and Void Evolution Enikő Regős Enikő Regős

Astrophysical observations and quantum physics Explain Λ from quantum fluctuations in gravity Explain Λ from quantum fluctuations in gravity Radiative corrections induce Λ Radiative corrections induce Λ Quantum gravity and accelerator physics Quantum gravity and accelerator physics Quantum black holes: energy spectrum, dependence with parameters of space- times, e.g. strings Quantum black holes: energy spectrum, dependence with parameters of space- times, e.g. strings Entropy Entropy

Quantum gravity and accelerator physics Obtain limits from collider experiments Obtain limits from collider experiments Graviton interference effects at Large Hadron Collider, CERN Graviton interference effects at Large Hadron Collider, CERN Decay modes of particles with mass in TeV range Decay modes of particles with mass in TeV range Hadron/lepton scatterings and Hadron/lepton scatterings and decays in extra-dimensional models decays in extra-dimensional models Super symmetry, string theory Super symmetry, string theory Limits from cosmology and astrophysics: cosmic rays and supernovae Limits from cosmology and astrophysics: cosmic rays and supernovae Particle astrophysics Particle astrophysics  Dark matter  mass of particles, Ex: Axions Ex: Axions Evidence from Evidence from observations for extra D observations for extra D  Alternative to missing mass problem : scale dependent G mass problem : scale dependent G

Cosmic rays and supernovae ; Cosmic rays : Nature’s free collider SN cores emit large fluxes of KK gravitons producing a cosmic background -> radiative decays : diffuse γ – ray background SN cores emit large fluxes of KK gravitons producing a cosmic background -> radiative decays : diffuse γ – ray background Cooling limit from SN 1987A neutrino burst -> bound on radius of extra dimensions Cooling limit from SN 1987A neutrino burst -> bound on radius of extra dimensions Cosmic neutrinos produce black holes, energy loss from graviton mediated interactions cannot explain cosmic ray events above a limit Cosmic neutrinos produce black holes, energy loss from graviton mediated interactions cannot explain cosmic ray events above a limit BH’s in observable collisions of elementary particles if ED BH’s in observable collisions of elementary particles if ED CR signals from mini BH’s in ED, evaporation of mini BHs CR signals from mini BH’s in ED, evaporation of mini BHs

Galaxy simulations and axion mass Collisional Cold Dark Matter interaction cross sections Collisional Cold Dark Matter interaction cross sections Halo structure, cusps Halo structure, cusps Number and size of extra dimensions Number and size of extra dimensions

High –z SNe: evolutionary effect in distance estimators ? Metallicity: Dependence with z Metallicity: Dependence with z Rates of various progenitors change with age of galaxy Rates of various progenitors change with age of galaxy Metallicity effect on C ignition density Metallicity effect on C ignition density  Neutrino cooling increased by URCA (21- Ne - 21-F) → slower light curve evolution at higher metallicities : small effect

Empirical relation between max. luminosity and light curve shape (speed) Systematic change with metallicity → far ELD SNe Ia fainter

Field theories : Cosmological constant induced by quantum fluctuations in gravity One loop effective potential for the curvature One loop effective potential for the curvature → matter free Einstein gravity has 2 phases : → matter free Einstein gravity has 2 phases : flat and strongly curved space times flat and strongly curved space times Radiative corrections → Cosmological constant : Λ>0 for the curved and Λ 0 for the curved and Λ<0 for the flat Infrared Landau pole in Λ>0 phase: Infrared Landau pole in Λ>0 phase: → Graviton confinement (unseccessful attempts of experiments) → Graviton confinement (unseccessful attempts of experiments) Or running Newton constant Or running Newton constant

Effective potential as function of curvature

Casimir effect Attractive force between neutral plates in QED Attractive force between neutral plates in QED Depends on geometry (e.g. not parallel) Depends on geometry (e.g. not parallel) Zero point energy Zero point energy Metric tensor controls geometry : Metric tensor controls geometry : analogy with gravity : analogy with gravity : Fit numerical results for gravity Fit numerical results for gravity

Energetically preferred curvature Minimize effective potential Minimize effective potential Quantum phase transition Quantum phase transition Savvidy vacuum : Savvidy vacuum : QCD vacuum in constant magnetic field unstable QCD vacuum in constant magnetic field unstable coupling (constant) depends on external B coupling (constant) depends on external B similarly in gravity G depends on external gravitational field similarly in gravity G depends on external gravitational field

Induced Λ and R² : In action In action F ( R ) = R – 2 λ – g R² F ( R ) = R – 2 λ – g R² stabilizes gravity stabilizes gravity ( R² inflation, ( R² inflation, conformally invariant to quintessence conformally invariant to quintessence - cosmological evolution ) - cosmological evolution )

Stability and matter fields λ_bare -> 2D phase diagram λ_bare -> 2D phase diagram include matter fields : include matter fields : 1. scalar 2. strong interaction : influence of confinement in gauge and influence of confinement in gauge and gravitational sectors on each other gravitational sectors on each other gravitational waves gravitational waves

2

Growth factors, Λ ≠ 0  f ≈ Ω^0.6_m + (1 + Ω_m /2 ) λ / 70  enters the peculiar velocity too  equation of state, w  Alcock – Paczynski effect

Spherical voids in Λ ≠ 0  coasting period provides more time for perturbations to grow  reducing the initial density contrast needed to produce nonlinear voids for fixed Ω_0, Λ ~ H ² _0  good for ΔT/T of CMB  density - velocity relation : model – independent, including biasing

Formation and evolution of voids  In a Λ – CDM Universe :  w w 1. distribution of void sizes in various simulations, Λ 2. 2MASS survey, Λ

Cosmological parameters from 6dF

2MASS, Aitoff projection

cz < 3000 km / s

3000 km / s < cz < 6000 km / s

Voids in 2MASS Supergalactic coordinates Supergalactic coordinates Supergalactic plane Supergalactic plane Equatorial coordinates Equatorial coordinates Peculiar velocity data Peculiar velocity data Cosmological parameters from outflow velocities Cosmological parameters from outflow velocities

Big voids Because it is an infrared survey Because it is an infrared survey the voids are shallower the voids are shallower less underdense than in optical less underdense than in optical

Interpretation of velocities  Not a simple dipole  Not a simple quadrupole (infall onto plane) Magnitude of radial velocities : variation with angle (Differential) Outflow: H_0 r Ω^0.6 / 5

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