Download - What is our universe made of ?
What is our universe What is our universe made of ?made of ?
quintessence !fire , air,
water, soil !
Dark Energy Dark Energy dominates the Universedominates the Universe
Energy - density in the Energy - density in the UniverseUniverse
==
Matter + Dark EnergyMatter + Dark Energy
25 % + 75 %25 % + 75 %
What is Dark Energy ?
Composition of the Composition of the universeuniverse
Atoms : Atoms : ΩΩb b = 0.045= 0.045
Dark Matter : Dark Matter : ΩΩdmdm= = 0.2250.225
Dark Energy : Dark Energy : ΩΩh h = 0.73= 0.73
critical densitycritical density ρρcc =3 H² M² =3 H² M² critical energy density of the critical energy density of the
universe universe ( M : reduced Planck-mass , H : Hubble ( M : reduced Planck-mass , H : Hubble
parameter )parameter )
ΩΩbb==ρρbb//ρρcc
fraction in baryons fraction in baryons energy density in baryons over energy density in baryons over
critical energy densitycritical energy density
Abell 2255 Cluster~300 Mpc
Matter : Everything that clumpsMatter : Everything that clumps
Dark MatterDark Matter ΩΩmm = 0.23 total “matter” = 0.23 total “matter” Most matter is dark !Most matter is dark ! So far tested only through gravitySo far tested only through gravity Every local mass concentration Every local mass concentration
gravitational potentialgravitational potential Orbits and velocities of stars and Orbits and velocities of stars and
galaxies measurement of gravitational galaxies measurement of gravitational potential potential
and therefore of local matter distributionand therefore of local matter distribution
gravitational lens , HST
ΩΩmm= 0.27= 0.27
Gravitationslinse,HST
Gravitationslinse,HST
Gravitationslinse,HST
bullet clusterbullet cluster
Dark MatterDark Matterin collisionin collision
Abell 2255 Cluster~300 Mpc
Matter : Everything that clumpsMatter : Everything that clumps
ΩΩmm= 0.27= 0.27
Dark Energy : Dark Energy : Energy density that does Energy density that does not clumpnot clump
Photons , gravitons : Photons , gravitons : insignificantinsignificant
spatially flat universespatially flat universe
theory (inflationary universe )theory (inflationary universe )
ΩΩtottot =1.0000……….x =1.0000……….x
observation ( WMAP )observation ( WMAP )
ΩΩtottot =1.02 (0.02) =1.02 (0.02)
ΩΩtottot = 1 = 1
Picture of the big bangPicture of the big bang
Anisotropy of background Anisotropy of background radiationradiation ::
size of hot and cold spotssize of hot and cold spots
Size of temperature fluctuationsSize of temperature fluctuationsin dependence on size of in dependence on size of
anisotropies ( angle )anisotropies ( angle )
ca 1 degreeca 1 degreeca 10 degreesca 10 degrees angleangle
contrastcontrast
Acoustic oscillations in plasmaAcoustic oscillations in plasma
ca 1 degreeca 1 degreeca 10 degreeca 10 degree
acoustic waves acoustic waves in the early Universe in the early Universe
lengthlengthcompu-compu-tabletable
ΩΩtottot=1=1
spatially flat Universespatially flat Universe
ΩΩtottot = = 11
ΩΩtottot=0.25=0.25ΩΩtottot = 1 = 1
WMAP 2006WMAP 2006
Polarization
ΩΩtottot=1=1
Dark EnergyDark Energy
ΩΩmm + X = 1 + X = 1
ΩΩmm : 25% : 25%
ΩΩhh : 75% : 75% Dark Dark
EnergyEnergyh : homogenous , often ΩΛ instead of Ωh
Space between clumpsSpace between clumps is not empty : is not empty :
Dark Energy !Dark Energy !
Dark Energy :Homogeneously distributed
Dark Energy density isDark Energy density isthe same at every point of the same at every point of
space space
“ homogeneous “ “ homogeneous “
No force in absence of No force in absence of matter –matter –
“ In what direction should it “ In what direction should it draw ? “draw ? “
Einstein’s equations :Einstein’s equations :almost static Dark Energy almost static Dark Energy
predicts accelerated expansion predicts accelerated expansion of Universe of Universe
Predictions for dark energy Predictions for dark energy cosmologiescosmologies
The expansion of the Universe
accelerates today !
Structure formation : Structure formation : OneOne primordial fluctuation primordial fluctuation
spectrumspectrum
Waerbeke
CMB agrees with
Galaxy distribution
Lyman – α
and
GravitationalLensing !
Power spectrum Power spectrum Baryon - PeakBaryon - Peak
SDSSSDSS
galaxy – galaxy – correlation –correlation –functionfunction
Structure Structure formation : formation : OneOne primordial primordial fluctuation- fluctuation- spectrumspectrum
M.Tegmark + …M.Tegmark + …
Dark Energy :Dark Energy :observations fit together !observations fit together !
consistent cosmological model !
Composition of the Composition of the UniverseUniverse
ΩΩb b = 0.045 = 0.045 visible visible clumpingclumping
ΩΩdmdm= 0.2 = 0.2 invisibleinvisible clumpingclumping
ΩΩh h = 0.75 = 0.75 invisibleinvisible homogeneoushomogeneous
Dark Energy –a cosmic mystery
What is Dark Energy ?
Cosmological Constant or Quintessence ?
Cosmological ConstantCosmological Constant- Einstein -- Einstein -
Constant Constant λλ compatible with all compatible with all symmetriessymmetries
No time variation in contribution to No time variation in contribution to energy densityenergy density
Why so small ? Why so small ? λλ/M/M44 = 10 = 10-120-120
Why important just today ?Why important just today ?
Cosmological mass scalesCosmological mass scales Energy densityEnergy density
ρρ ~ ( 2.4×10 ~ ( 2.4×10 -3-3 eV )eV )- 4- 4
Reduced Planck Reduced Planck massmass
M=2.44M=2.44×10 ×10 2727 eV eV Newton’s constantNewton’s constant
GGNN=(8=(8ππM²)M²)
Only ratios of mass scales are observable !Only ratios of mass scales are observable !
homogeneous dark energy: homogeneous dark energy: ρρhh/M/M44 = 6.5 = 6.5 10ˉ¹²¹10ˉ¹²¹
matter: matter: ρρmm/M/M4= 3.5 10ˉ¹²¹= 3.5 10ˉ¹²¹
Time evolutionTime evolution
ρρmm/M/M4 4 ~ aˉ~ aˉ³ ³ ~~
ρρrr/M/M4 4 ~ aˉ~ aˉ44 ~ ~ t t -2-2 radiation dominated universeradiation dominated universe
Huge age small ratioHuge age small ratio
Same explanation for small dark Same explanation for small dark energy?energy?
tˉ² matter dominated universe
tˉ3/2 radiation dominated universe
Cosm. Const. | Quintessence static | dynamical
QuintessenceQuintessence Dynamical dark Dynamical dark energy ,energy ,
generated by generated by scalarscalar fieldfield
(cosmon)(cosmon)C.Wetterich,Nucl.Phys.B302(1988)668, C.Wetterich,Nucl.Phys.B302(1988)668, 24.9.8724.9.87P.J.E.Peebles,B.Ratra,ApJ.Lett.325(1988)L17, P.J.E.Peebles,B.Ratra,ApJ.Lett.325(1988)L17, 20.10.8720.10.87
Prediction :Prediction :
homogeneous dark energy homogeneous dark energyinfluences recent cosmologyinfluences recent cosmology
- of same order as dark - of same order as dark matter -matter -
Original models do not fit the present observationsOriginal models do not fit the present observations……. modifications. modifications
QuintessenceQuintessence
Cosmon – Field Cosmon – Field φφ(x,y,z,t)(x,y,z,t)
similar to electric field , but no direction similar to electric field , but no direction ( scalar field )( scalar field )Homogeneous und isotropic Universe : Homogeneous und isotropic Universe :
φφ(x,y,z,t)=(x,y,z,t)=φφ(t)(t)
Potential und kinetic energy of the cosmon -Potential und kinetic energy of the cosmon -fieldfield
contribute to a dynamical energy density of contribute to a dynamical energy density of the Universe ! the Universe !
CosmonCosmon Scalar field changes its value even Scalar field changes its value even
in the in the presentpresent cosmological epochcosmological epoch Potential und kinetic energy of Potential und kinetic energy of
cosmon contribute to the energy cosmon contribute to the energy density of the Universedensity of the Universe
Time - variable dark energy : Time - variable dark energy :
ρρhh(t) decreases with time !(t) decreases with time !
Evolution of cosmon fieldEvolution of cosmon field
Field equationsField equations
Potential V(Potential V(φφ) determines details of the ) determines details of the modelmodel
V(V(φφ) =M) =M4 4 exp( - exp( - αφαφ/M )/M )
for increasing for increasing φφ the potential the potential decreases towards zero !decreases towards zero !
CosmonCosmon Tiny massTiny mass
mmcc ~ H (depends on time ! ) ~ H (depends on time ! )
New long - range interactionNew long - range interaction
““Fundamental” Fundamental” InteractionsInteractions
Strong, electromagnetic, weakinteractions
gravitation cosmodynamics
On astronomical length scales:
graviton
+
cosmon
observation will decide !observation will decide !
Time dependence of dark Time dependence of dark energyenergy
cosmological constant : Ωh ~ t² ~ (1+z)-3
M.Doran,…
Observational bounds on Observational bounds on ΩΩhh
G.RobberG.Robbers , s , M.Doran ,M.Doran ,……
exponential potentialexponential potentialconstant fraction in dark constant fraction in dark
energyenergy
can explain can explain order order
of magnitude of magnitude
of dark energy !of dark energy !
ΩΩh h = 3/= 3/αα22 V(V(φφ) =M) =M4 4 exp( - exp( - αφαφ/M )/M )
Cosmic AttractorsCosmic Attractors
Solutions independent of initial conditions
typically V~t -2
φ ~ ln ( t )
Ωh ~ const.
details depend on V(φ)or kinetic term
early cosmology
realistic quintessencerealistic quintessence
fraction in dark energy has fraction in dark energy has to to
increase in “recent time” !increase in “recent time” !
Quintessence becomes Quintessence becomes important “today”important “today”
Key questions for Key questions for quintessencequintessence
Why does cosmon potential vanish for Why does cosmon potential vanish for infinite time ? infinite time ? V(V(φφ) =M) =M4 4 exp( - exp( - αφαφ/M )/M )
Why is time variation of fundamental Why is time variation of fundamental couplings small ? couplings small ? ( e.g. fine structure ( e.g. fine structure constant , electron-proton mass ratio )constant , electron-proton mass ratio )
Why does Dark Energy dominate only in Why does Dark Energy dominate only in recent cosmology ( Why now ? – recent cosmology ( Why now ? – problem )problem )
Key questions for Key questions for quintessencequintessence
Why does cosmon potential vanish for infinite Why does cosmon potential vanish for infinite time ? time ? V(V(φφ) =M) =M4 4 exp( - exp( - αφαφ/M )/M )
Dilatation symmetry in higher dimensions – not Dilatation symmetry in higher dimensions – not todaytoday
Why is time variation of fundamental couplings Why is time variation of fundamental couplings small ? small ? ( e.g. fine structure constant , electron-proton ( e.g. fine structure constant , electron-proton mass ratio )mass ratio )
Fixed point behavior – not todayFixed point behavior – not today
Why does Dark Energy dominate only in recent Why does Dark Energy dominate only in recent cosmology ( Why now ? – problem )cosmology ( Why now ? – problem )
Growing neutrino mass - Growing neutrino mass - todaytoday
coincidence problemcoincidence problem
What is responsible for increase of What is responsible for increase of ΩΩhh for z < 6 ? for z < 6 ?
Why now ?Why now ?
Neutrinos in cosmologyNeutrinos in cosmology
only small fraction of energy only small fraction of energy densitydensity
only sub-leading role ?only sub-leading role ?
Cosmon – neutrino Cosmon – neutrino couplingcoupling
Can be somewhat stronger than Can be somewhat stronger than gravitational couplinggravitational coupling
Neutrino mass depends on value of Neutrino mass depends on value of cosmon fieldcosmon field
In contrast : cosmon – atom coupling must In contrast : cosmon – atom coupling must be weaker than gravitybe weaker than gravity
Masses and coupling constants are determined by properties of vacuum !Similar to Maxwell – equations in matter
Fundamental couplings Fundamental couplings in quantum field theoryin quantum field theory
Spontaneous symmetry Spontaneous symmetry breaking to be confirmed breaking to be confirmed
at the LHCat the LHC
Have coupling constants in the early Universe other values ?Yes !
Restoration of symmetryRestoration of symmetryat high temperature at high temperature in the early Universein the early Universe
High THigh TSYM SYM <<φφ>=0>=0
Low TLow TSSBSSB<<φφ>=>=φφ00 ≠≠ 0 0
high T :high T :Less orderLess orderMore More symmetrysymmetry
Example:Example:MagnetsMagnets
In hot plasma In hot plasma of early Universe :of early Universe :
masses of electron und masses of electron und muon muon
not different!not different!
similar strength of similar strength of electromagnetic and weak electromagnetic and weak
interactioninteraction
Particle masses in Particle masses in quintessence cosmologyquintessence cosmology
can depend on value of can depend on value of cosmon fieldcosmon field
similar to dependence on value of Higgs fieldsimilar to dependence on value of Higgs field
Varying couplingsVarying couplings
only question :only question :
How strong is How strong is presentpresent variation of variation of couplings ?couplings ?
Cosmon – atom coupling Cosmon – atom coupling inducesinduces
violation of equivalence violation of equivalence principleprincipleDifferent couplings Different couplings
of cosmon to of cosmon to proton and neutronproton and neutron
Differential Differential accelerationacceleration
““Violation of Violation of equivalence equivalence principle”principle”
earth
p,n
p,n
cosmon
only apparent : new “fifth force” !only apparent : new “fifth force” !
growing neutrinogrowing neutrinoquintessencequintessence
growing neutrino mass growing neutrino mass triggers transition to triggers transition to
almost static dark energyalmost static dark energy
growinggrowingneutrinoneutrinomassmass
L.Amendola, M.Baldi,…L.Amendola, M.Baldi,…
effective cosmological effective cosmological triggertrigger
for stop of cosmon for stop of cosmon evolution :evolution :
neutrinos get non-neutrinos get non-relativisticrelativistic
this has happened recently !this has happened recently ! sets scales for dark energy !sets scales for dark energy !
connection between dark connection between dark energy energy
and neutrino propertiesand neutrino properties
present present equationequationof state given of state given bybyneutrino mass neutrino mass !!
present dark energy density given by neutrino masspresent dark energy density given by neutrino mass
= 1.27= 1.27
cosmological selectioncosmological selection
present value of dark energy density present value of dark energy density set by cosmological event :set by cosmological event :
neutrinos become non – relativistic neutrinos become non – relativistic
not given by ground state properties !not given by ground state properties !
cosmon coupling to cosmon coupling to neutrinosneutrinos
basic ingredient :basic ingredient :
Cosmon coupling to Cosmon coupling to neutrinosneutrinos
can be large !can be large !
interesting effects for cosmology if interesting effects for cosmology if neutrino mass is growingneutrino mass is growing
growing neutrinos can stop the growing neutrinos can stop the evolution of the cosmonevolution of the cosmon
transition from early scaling solution transition from early scaling solution to cosmological constant dominated to cosmological constant dominated cosmologycosmology
L.Amendola,M.Baldi,…L.Amendola,M.Baldi,…
Fardon,Nelson,WeinerFardon,Nelson,Weiner
dark energy fraction dark energy fraction determined by neutrino determined by neutrino
massmass
constant neutrino - cosmon coupling constant neutrino - cosmon coupling ββ
variable neutrino - cosmon couplingvariable neutrino - cosmon coupling
cosmon evolutioncosmon evolution
scaliscalingng
““stopped”stopped”
stopped scalar fieldstopped scalar fieldmimicks amimicks a
cosmological constantcosmological constant( almost …)( almost …)
rough approximation for dark energy :rough approximation for dark energy : before redshift 5-6 : scaling ( dynamical ) before redshift 5-6 : scaling ( dynamical ) after redshift 5-6 : almost static after redshift 5-6 : almost static
( cosmological constant )( cosmological constant )
growing neutrinos growing neutrinos change cosmon evolutionchange cosmon evolution
modification of conservation equation for neutrinosmodification of conservation equation for neutrinos
effective stop of cosmon effective stop of cosmon evolutionevolution
cosmon evolution almost stops cosmon evolution almost stops onceonce
neutrinos get non –relativisticneutrinos get non –relativistic ß gets largeß gets large
This alwaysThis alwayshappens happens for for φφ → → φφt t !!
crossover to dark energy crossover to dark energy dominated universedominated universe
starts at time when “neutrino force” becomes starts at time when “neutrino force” becomes important for the evolution of the cosmon fieldimportant for the evolution of the cosmon field
cosmological selection !cosmological selection !
Tests for growing Tests for growing neutrino quintessenceneutrino quintessence
Hubble parameterHubble parameteras compared to as compared to ΛΛCDMCDM
Hubble parameter ( z < Hubble parameter ( z < zzc c ))
only small only small differencedifferencefrom from ΛΛCDM !CDM !
bounds on average neutrino bounds on average neutrino massmass
Can time evolution of Can time evolution of neutrino mass be neutrino mass be
observed ?observed ?Experimental determination of neutrino mass Experimental determination of neutrino mass
may turn out higher than cosmological upper may turn out higher than cosmological upper bound in model with constant neutrino massbound in model with constant neutrino mass
( KATRIN, neutrino-less double beta decay )( KATRIN, neutrino-less double beta decay )
GERDAGERDA
neutrino fluctuationsneutrino fluctuations
neutrino structures become nonlinear neutrino structures become nonlinear at z~1 for supercluster scalesat z~1 for supercluster scales
stable neutrino-cosmon lumps exist stable neutrino-cosmon lumps exist N.Brouzakis , N.Tetradis ,…N.Brouzakis , N.Tetradis ,…
D.Mota , G.Robbers , V.Pettorino , …D.Mota , G.Robbers , V.Pettorino , …
Formation of neutrino Formation of neutrino lumpslumps
N- body simulation M.Baldi et N- body simulation M.Baldi et alal
ConclusionsConclusions
Cosmic event triggers qualitative Cosmic event triggers qualitative change in evolution of cosmonchange in evolution of cosmon
Cosmon stops changing after Cosmon stops changing after neutrinos become non-relativisticneutrinos become non-relativistic
Explains why nowExplains why now Cosmological selectionCosmological selection Model can be distinguished from Model can be distinguished from
cosmological constantcosmological constant
SummarySummary
o ΩΩhh = 0.73 = 0.73
o Q/Q/ΛΛ : dynamical und static dark energy will be : dynamical und static dark energy will be distinguishabledistinguishable
o growing neutrino mass can explain why now growing neutrino mass can explain why now problemproblem
o Q : time varying fundamental coupling Q : time varying fundamental coupling “constants” “constants”
violation of equivalence principleviolation of equivalence principle
EnEndd
varying neutrino – cosmon varying neutrino – cosmon couplingcoupling
specific modelspecific model can naturally explain why neutrino – can naturally explain why neutrino –
cosmon coupling is much larger than cosmon coupling is much larger than atom – cosmon coupling atom – cosmon coupling
neutrino massneutrino mass
seesaw seesaw andandcascadecascademechanismechanismm
omit generation omit generation structurestructure
triplet expectation value ~ doublet squaredtriplet expectation value ~ doublet squared
cascade mechanismcascade mechanism
triplet expectation value ~triplet expectation value ~
M.Magg , …M.Magg , …G.Lazarides , Q.Shafi , …G.Lazarides , Q.Shafi , …
cascadecascade
varying neutrino massvarying neutrino mass
triplet mass depends on cosmon field triplet mass depends on cosmon field φφ
neutrino mass depends on neutrino mass depends on φφ
εε ≈≈ -0.05 -0.05
cascade mechanismcascade mechanism
triplet expectation value ~triplet expectation value ~
““singular” neutrino masssingular” neutrino mass
triplet mass vanishes for triplet mass vanishes for φφ → → φφtt
neutrino mass diverges for neutrino mass diverges for φφ → → φφtt
strong effective strong effective neutrino – cosmon neutrino – cosmon
coupling coupling for for φφ → → φφtt
typical present value : typical present value : ββ ≈≈ 50 50 cosmon mediated attraction between neutrinoscosmon mediated attraction between neutrinosis about 50is about 5022 stronger than gravitational attraction stronger than gravitational attraction
crossover fromcrossover fromearly scaling solution to early scaling solution to
effective cosmological effective cosmological constantconstant
early scaling solution ( tracker early scaling solution ( tracker solution )solution )
neutrino mass unimportant in early cosmologyneutrino mass unimportant in early cosmology
effective cosmological effective cosmological triggertrigger
for stop of cosmon for stop of cosmon evolution :evolution :
neutrinos get non-neutrinos get non-relativisticrelativistic
this has happened recently !this has happened recently ! sets scales for dark energy !sets scales for dark energy !
dark energy fraction dark energy fraction determined by neutrino determined by neutrino
massmass
constant neutrino - cosmon coupling constant neutrino - cosmon coupling ββ
variable neutrino - cosmon couplingvariable neutrino - cosmon coupling
cosmon evolutioncosmon evolution
scaliscalingng
““stopped”stopped”
Equation of stateEquation of state
p=T-V pressure p=T-V pressure kinetic energykinetic energy
ρρ=T+V energy density=T+V energy density
Equation of stateEquation of state
Depends on specific evolution of the scalar Depends on specific evolution of the scalar fieldfield
Negative pressureNegative pressure
w < 0 w < 0 ΩΩh h increases increases (with decreasing z (with decreasing z
))
w < -1/3 expansion of the Universe isw < -1/3 expansion of the Universe is
acceleratingaccelerating
w = -1 cosmological constantw = -1 cosmological constant
late universe withlate universe withsmall radiation small radiation component :component :
A few referencesA few references
C.Wetterich , Nucl.Phys.B302,668(1988) , received 24.9.1987C.Wetterich , Nucl.Phys.B302,668(1988) , received 24.9.1987
P.J.E.Peebles,B.Ratra , Astrophys.J.Lett.325,L17(1988) , received 20.10.1987P.J.E.Peebles,B.Ratra , Astrophys.J.Lett.325,L17(1988) , received 20.10.1987
B.Ratra,P.J.E.Peebles , Phys.Rev.D37,3406(1988) , received 16.2.1988B.Ratra,P.J.E.Peebles , Phys.Rev.D37,3406(1988) , received 16.2.1988
J.Frieman,C.T.Hill,A.Stebbins,I.Waga , Phys.Rev.Lett.75,2077(1995)J.Frieman,C.T.Hill,A.Stebbins,I.Waga , Phys.Rev.Lett.75,2077(1995)
P.Ferreira, M.Joyce , Phys.Rev.Lett.79,4740(1997)P.Ferreira, M.Joyce , Phys.Rev.Lett.79,4740(1997)
C.Wetterich , Astron.Astrophys.301,321(1995)C.Wetterich , Astron.Astrophys.301,321(1995)
P.Viana, A.Liddle , Phys.Rev.D57,674(1998)P.Viana, A.Liddle , Phys.Rev.D57,674(1998)
E.Copeland,A.Liddle,D.Wands , Phys.Rev.D57,4686(1998)E.Copeland,A.Liddle,D.Wands , Phys.Rev.D57,4686(1998)
R.Caldwell,R.Dave,P.Steinhardt , Phys.Rev.Lett.80,1582(1998)R.Caldwell,R.Dave,P.Steinhardt , Phys.Rev.Lett.80,1582(1998)
P.Steinhardt,L.Wang,I.Zlatev , Phys.Rev.Lett.82,896(1999)P.Steinhardt,L.Wang,I.Zlatev , Phys.Rev.Lett.82,896(1999)