Dark Energy and Dark Energy and Void EvolutionVoid Evolution

Enikő RegősEnikő Regős

Astrophysical observations and quantum Astrophysical observations and quantum physicsphysics

Explain Explain ΛΛ from from quantum quantum fluctuations in fluctuations in gravitygravity

Radiative Radiative corrections induce corrections induce ΛΛ

Quantum gravity and Quantum gravity and accelerator physicsaccelerator physics

Quantum black holesQuantum black holes: : energy spectrum, energy spectrum, dependence with dependence with parameters of space-parameters of space-times,times, e.g.e.g. stringsstrings

EntropyEntropy

Quantum gravity and accelerator Quantum gravity and accelerator physicsphysics

Obtain limits from collider Obtain limits from collider experimentsexperiments

Graviton interference effects Graviton interference effects at Large Hadron Collider, at Large Hadron Collider, CERNCERN

Decay modes of particles Decay modes of particles with mass in TeV rangewith mass in TeV range

Hadron/lepton scatterings Hadron/lepton scatterings andand

decays in extra-dimensional decays in extra-dimensional modelsmodels

Super symmetry, string Super symmetry, string theorytheory

Limits from Limits from cosmology and cosmology and astrophysics: cosmic astrophysics: cosmic rays and supernovaerays and supernovae

Particle astrophysics Particle astrophysics Dark matterDark matter mass of particles, mass of particles, Ex:Ex: Axions Axions Evidence fromEvidence from observations for extra observations for extra

DD Alternative to Alternative to

missingmissing mass problemmass problem: : scale scale

dependent G dependent G

Cosmic rays and supernovae ;Cosmic rays and supernovae ;Cosmic rays : Nature’s free colliderCosmic rays : Nature’s free collider

SN cores emit large fluxes of KK gravitons producing a SN cores emit large fluxes of KK gravitons producing a cosmic background -> radiative decays : diffuse cosmic background -> radiative decays : diffuse γγ – ray – ray backgroundbackground

Cooling limit from SN 1987A neutrino burst -> bound on Cooling limit from SN 1987A neutrino burst -> bound on radius of extra dimensionsradius of extra dimensions

Cosmic neutrinos produce black holes, energy loss from Cosmic neutrinos produce black holes, energy loss from graviton mediated interactions cannot explain cosmic graviton mediated interactions cannot explain cosmic ray events above a limitray events above a limit

BH’s in observable collisions of elementary particles if BH’s in observable collisions of elementary particles if EDED

CR signals from mini BH’s in ED, evaporation of mini CR signals from mini BH’s in ED, evaporation of mini BHsBHs

Galaxy simulations and axion massGalaxy simulations and axion mass

Collisional Cold Dark Matter interaction Collisional Cold Dark Matter interaction cross sections cross sections

Halo structure, cuspsHalo structure, cusps Number and size of extra dimensionsNumber and size of extra dimensions

High –z SNe: evolutionary effect in distance High –z SNe: evolutionary effect in distance estimators ?estimators ?

Metallicity: Dependence with zMetallicity: Dependence with z Rates of various progenitors change Rates of various progenitors change

with age of galaxywith age of galaxy Metallicity effect on C ignition densityMetallicity effect on C ignition density

Neutrino cooling increased by URCA Neutrino cooling increased by URCA (21-Ne - 21-F) → slower light curve (21-Ne - 21-F) → slower light curve evolution at higher metallicities : evolution at higher metallicities : small effectsmall effect

Empirical relation between max. luminositEmpirical relation between max. luminosityy

and light curve shape (speed)and light curve shape (speed)

Systematic change with metallicity Systematic change with metallicity →→ farfar ELD SNe Ia ELD SNe Ia fainter fainter

Field theories :Field theories :Cosmological constant induced by Cosmological constant induced by

quantum fluctuations in gravityquantum fluctuations in gravity One loop effective potential for the curvatureOne 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 timesflat and strongly curved space times Radiative corrections Radiative corrections →→ Cosmological constant Cosmological constant

: : ΛΛ>0>0 for the curved and for the curved and ΛΛ<0<0 for the flat for the flat Infrared Landau pole in Infrared Landau pole in ΛΛ>0 phase: >0 phase:

→→ Graviton confinement Graviton confinement (unseccessful (unseccessful attempts of experiments) attempts of experiments)

Or running Newton constantOr running Newton constant

Effective potential as function of Effective potential as function of curvaturecurvature

Casimir effect Casimir effect Attractive force between neutral plates in Attractive force between neutral plates in

QEDQED Depends on geometry (e.g. not parallel)Depends on geometry (e.g. not parallel) Zero point energyZero point energy Metric tensor controls geometry :Metric tensor controls geometry :

analogy with gravity :analogy with gravity : Fit numerical results for gravityFit numerical results for gravity

Energetically preferred Energetically preferred curvaturecurvature

Minimize effective potentialMinimize effective potential Quantum phase transitionQuantum phase transition Savvidy vacuum :Savvidy vacuum :

QCD vacuum in constant magnetic field QCD vacuum in constant magnetic field unstable unstable

coupling (constant) depends on external B coupling (constant) depends on external B

similarly in gravity G depends on external similarly in gravity G depends on external gravitational field gravitational field

Induced Induced ΛΛ and R and R² ² ::

In actionIn action

F ( R ) = R – 2 F ( R ) = R – 2 λλ – g R² – g R² stabilizes gravity stabilizes gravity ( R( R² inflation² inflation , ,

conformally invariant to conformally invariant to quintessence quintessence

- cosmological evolution )- cosmological evolution )

Stability and matter fieldsStability and matter fields

λλ_bare -> 2D _bare -> 2D phase diagramphase diagram include matter fieldsinclude matter fields : :

1.1. scalarscalar

2.2. strong interaction : strong interaction :

influence of confinement in gauge influence of confinement in gauge andand

gravitational sectors on each othergravitational 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 ~ H²_0 good for ΔT/T of CMB density - velocity relation : model – independent, including

biasing

Formation and evolution of voids

In a Λ–CDM Universe : w1. distribution of void sizes in various

simulations, Λ2. 2MASS survey, Λ

Cosmological parameters Cosmological parameters from 6dFfrom 6dF

2MASS, Aitoff projection

cz < 3000 km / scz < 3000 km / s

3000 km / s < cz < 6000 km 3000 km / s < cz < 6000 km / s/ s

Voids in 2MASSVoids in 2MASS

Supergalactic coordinatesSupergalactic coordinates Supergalactic planeSupergalactic plane Equatorial coordinatesEquatorial coordinates Peculiar velocity dataPeculiar velocity data Cosmological parameters from Cosmological parameters from

outflow velocitiesoutflow velocities

Big voidsBig voids

Because it is an infrared surveyBecause it is an infrared survey

the voids are shallowerthe voids are shallower

less underdense than in opticalless 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

Thank you for your Thank you for your attentionattention