christian stegmann, cosmology, cern 2008 time cosmology cosmology christian stegmann university of...
DESCRIPTION
Christian Stegmann, Cosmology, CERN 2008 Time … one of eight planets todayTRANSCRIPT
Christian Stegmann, Cosmology, CERN 2008
Time
CosmologyCosmology Christian StegmannUniversity of Erlangen-Nuremberg
Big Bang today
Christian Stegmann, Cosmology, CERN 2008
Time
The Earth …The Earth …Heute
Christian Stegmann, Cosmology, CERN 2008
Time
… … one of eight planetsone of eight planetstoday
Christian Stegmann, Cosmology, CERN 2008
Time
StarsStarstoday
Christian Stegmann, Cosmology, CERN 2008
Time
The Milky Way ...The Milky Way ...today
Christian Stegmann, Cosmology, CERN 2008
Time
... full of stars... full of starstoday
Christian Stegmann, Cosmology, CERN 2008
Time
and nebulaeand nebulaetoday
Christian Stegmann, Cosmology, CERN 2008
Time
Our Milky WayOur Milky Waytoday
Christian Stegmann, Cosmology, CERN 2008
Time
The Universe is full of galaxiesThe Universe is full of galaxiestoday
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxy clusterGalaxy clustertoday
Christian Stegmann, Cosmology, CERN 2008
Time
Edwin Hubbles DiscoveryEdwin Hubbles Discovery
• Galaxies travel away from us
• the further away, the faster
today
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxies are moving Galaxies are moving today
Christian Stegmann, Cosmology, CERN 2008
Time
Do we understand that?Do we understand that?
• We are the centre of the Universe!
• The Universe is expanding– Space between galaxies is getting larger
Scientifically more attractive!
today
Christian Stegmann, Cosmology, CERN 2008
Timetoday
Christian Stegmann, Cosmology, CERN 2008
Time
some time later
today
Christian Stegmann, Cosmology, CERN 2008
Time
How do we measure this?How do we measure this?
• Measurement of the velocity– velocity-meter?
• Distance– Ruler?
today
Christian Stegmann, Cosmology, CERN 2008
Time
Measurement of the velocity via the Measurement of the velocity via the red-shiftred-shift
today
Christian Stegmann, Cosmology, CERN 2008
Time
Cosmological red shiftCosmological red shift
Space is expanding
today
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxy-spektroscopyGalaxy-spektroscopy
Calcium
Magnesium
Sodium
Galaxy-spektrum
Star-spektrum
vGalaxy ~ 12000 km/s
today
Christian Stegmann, Cosmology, CERN 2008
Time
Distance measurementDistance measurement
apparent brightness ~ true brightness . 1/R2
R
today
Christian Stegmann, Cosmology, CERN 2008
Time
distance, R
brightness
known distance
measuredbrightness
One point andall is determined
measuredbrightness
measureddistance
today
Christian Stegmann, Cosmology, CERN 2008
Time
We need lamps!We need lamps!
today
Christian Stegmann, Cosmology, CERN 2008
Time
Star explosionsStar explosions
• Supernova Typ Ia• Exploding white dwarfs
– nuclear bomb of the size of the Earth!
• Bright as a whole galaxy
• Light up and disappear after a few weeks
Supernova 1994D
today
Christian Stegmann, Cosmology, CERN 2008
Time
Where is the supernova?Where is the supernova?today
Christian Stegmann, Cosmology, CERN 2008
Time
Here!Here!today
Christian Stegmann, Cosmology, CERN 2008
Time
„„Standard candles“Standard candles“today
Christian Stegmann, Cosmology, CERN 2008
Time
The Hubble-DiagramThe Hubble-Diagram
red shift (velocity)
D
ista
nce
Heute
Christian Stegmann, Cosmology, CERN 2008
Time
• The Universe is expanding (acclerating)!• The Universe was smaller at earlier times
• The Universe was created in a hot phase
The Big Bang
today
Christian Stegmann, Cosmology, CERN 2008
Time
World modelsWorld models
today
Christian Stegmann, Cosmology, CERN 2008
Time
General relativityGeneral relativity
• Einstein 1916• Describes all gravitationally bound
systems– planets– black holes – the Universe
• Mass produces curvature of the space• Curvature tells masses how to move
→ gravitation
today
Christian Stegmann, Cosmology, CERN 2008
Time
Space curvatureSpace curvaturetoday
Christian Stegmann, Cosmology, CERN 2008
Time
SolutionSolution
• Cosmological principle– We see what every other sees – Isotrop and homogeneous
Universe
• Friedmann Universe (1922)
• World models depend only on – Expansion – Gravitational attraction
Homogeneous but not isotrop
Isotrop but not homogeneous
Isotrop AND homogeneous
Heute
Christian Stegmann, Cosmology, CERN 2008
Time
Distribution of galaxiesDistribution of galaxiestoday
Christian Stegmann, Cosmology, CERN 2008
Time
The accelerated UniverseThe accelerated Universe
• Einsteins cosmological constant
• cosmological constant acts like an anti-gravitation
Christian Stegmann, Cosmology, CERN 2008
Time
A travel through the timeA travel through the time
Christian Stegmann, Cosmology, CERN 2008
Time
First there was …First there was …0
Christian Stegmann, Cosmology, CERN 2008
Time
From Big Bang until todayFrom Big Bang until today0
Christian Stegmann, Cosmology, CERN 2008
Time
A time travelA time travel
• Age = 10-42 s– The beginning of physics
• Age = 10-36 s, T = 1027 K– Strong and electroweak force decouple
10-42 s
Christian Stegmann, Cosmology, CERN 2008
Time
The inflationThe inflation
• Age = 10-36 s, T = 1021 K – Sudden expansion of the Universe by a factor 1020 – 1030
– The Universe gets flat!
10-36s
Christian Stegmann, Cosmology, CERN 2008
Time
The battleThe battle
• Age = 10-6 s, T = 1012 Kelvin– Matter and antimatter annihilate– Matter-antimatter-ratio
100000001 : 10000000
– Matter-photon-ratio
1 : 100000000
10-6 s
Christian Stegmann, Cosmology, CERN 2008
Time
NukleosynthesisNukleosynthesis
• Age = 1 min, T = 109 K– Generation of light
elements– Hydrogen, Deuterium,
Helium, Lithium
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Nuclear fusionNuclear fusion
• Fusion in collisions
• Fusion requries high temperatures and large densities
particle distanceForv
ce
Strong electo-static repulsion at intermediate distances
Strong nuclear attraction at smal distances
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Primordiale NukleosynthesisPrimordiale Nukleosynthesis
• Explains the abundances of light elements– 74% Hydrogen
– 25% Helium
– 1% other
• Baryonic density– 3,5∙10-31 g/cm3 or
– 0,2 Hydrogen atoms/m3
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Generation of atomsGeneration of atoms
• Age = 370000 Jahre, T = 3000 Kelvin– First atoms generated– The Universe becomes transparent
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
Can we see the Big Bang?Can we see the Big Bang?
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
Back into the pastBack into the past
4 light years
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
2 million light years
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
some billions of light years
Each view into the Universe isa view back into the past
Back into the pastBack into the past
Christian Stegmann, Cosmology, CERN 2008
Time
370000 Jahre
The Big Bang fills the skyThe Big Bang fills the sky
Christian Stegmann, Cosmology, CERN 2008
Time
The Big Bang past - nowThe Big Bang past - now
Past:Light 3000 K
today:Mikrowaves 3 K
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
1965 – The discovery1965 – The discovery
Microwave radiation from the cosmos
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
COBE and WMAPCOBE and WMAP
• COBE– COsmic Background Explorer
– 1989 – 1993
– Nobel price 2006 (G. Smoot, J. Mather)
• WMAP– Wilkinson Microwave Anisotropy
Probe
– Start 2001
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
The microwave backgroundThe microwave background
T = 2.7 K
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
T = 0,0035 K
The Earth is movingThe Earth is moving370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
The spectrumThe spectrum370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
The history of the cosmic The history of the cosmic background radiationbackground radiation
observer
Surface of last scattering
Edge of the visible Universe.black body radiation
The visible Universe
black body radiation
370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
T = 0,000018 K
The echo of the big bangThe echo of the big bang370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
Multipol expansionMultipol expansion370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
The power spectrumThe power spectrum370000 years
Christian Stegmann, Cosmology, CERN 2008
Time
Cosmological ParameterCosmological Parameter
– Total energiy density 1.003 ± 0.015
– Matter density 0.24 ± 0.04
– Baryon density 0.042 ± 0.004
– Vakuum energy density 0.76 ± 0.05
– Neutrino density < 0.014
– Age of the Universe 13.7 ± 0.2 Gyr
Christian Stegmann, Cosmology, CERN 2008
Time
60%
40%
20%
0%
80%
100%
Matter
Neutrinos
Stars
Neue Formvon Energie
Neue Formvon Materie
370000 Jahre
Christian Stegmann, Cosmology, CERN 2008
Time
SummarySummary
• Our Universe was created in a Big Bang– Galaxy move away from us
– Abundances of light elements
– Cosmic microwave background
• 97% of the energy density of the Universe is unknown!
today
Christian Stegmann, Cosmology, CERN 2008
Time
Christian Stegmann, Cosmology, CERN 2008
Time
Doppler effectDoppler effect
low frequency
red shift
high frequency
blue shift
today
Christian Stegmann, Cosmology, CERN 2008
Time
Spektra for identificationSpektra for identificationtoday
Christian Stegmann, Cosmology, CERN 2008
Time
Parameter of an expanding UniverseParameter of an expanding Universe
• Expansion ↔ Gravitational acceleration
• Expansion– Hubble constant H0 is a measure for the strength of the
expansion: H0 = 20 km/s/MLj
• Gravitational acceleration– Normal matter slows down the expansion (mean density
ρ) – critical density, requried to stop expansion:
ρkrit = 3 H02/8πG = 10-29 g/cm3
today
Christian Stegmann, Cosmology, CERN 2008
Time
Geometry of the UniverseGeometry of the Universe
• Balance between contraction and expansion expresse by Ω0 = ρ/ρkrit
– Ω0 > 1, ρ > ρkritGravitation wins, Universe collapse
– Ω0 = 1, ρ = ρkritExpansion eventually stopps
– Ω0 < 1, ρ < ρkritExpansion wins, Universum is expanding forever
• Λ > 0, fate of the Universe not connected to the geometry
today
Christian Stegmann, Cosmology, CERN 2008
Time
Why not in stars?Why not in stars?
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Fusion in starsFusion in stars1 min
Christian Stegmann, Cosmology, CERN 2008
Time
•
• Erwarte ungefähr genauso viel Helium wie andere Elemente mit großer Masse– Verhältnis: 75% H, 13% He, 12% Rest
Fusion in starsFusion in stars
Zeit
Ker
n Te
mpe
ratu
r
107 K
108 K
109 K
Wasserstoff-Brennen
Helium-Brennen
carbon-burning
1.5x107 K
6x108 K
1x108 K
H Brenn-SchaleHe Brenn-Schale
C Brenn-SchaleO Brenn-SchaleSi Brenn-Schale
Fe Kern- keine Fusion
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Vergleich Stellarer und Vergleich Stellarer und Primordialer NukleosynthesePrimordialer Nukleosynthese
109 : 11:1Photon-Baryon-Verhältnis
10-5 g/cm3 (wie die Luft in diesem Raum)
100 g/cm3Dichte
FallendAnsteigendTemperatur-entwicklung
MinutenMilliarden von Jahren
Zeitskala
Primordiale Nukleosynthese
Stellare Nukleosynthese
1 min
Christian Stegmann, Cosmology, CERN 2008
Time
Kosmologische ParameterKosmologische Parameter370000 Jahre
Christian Stegmann, Cosmology, CERN 2008
Time
Dunkle MaterieDunkle Materie
• Rotationskurven von Galaxien
• Elliptische Galaxien
• Gravitationslinsen
• Mikrowellen-Hintergrund
Heute
Christian Stegmann, Cosmology, CERN 2008
Time
RotationskurvenRotationskurvenHeute
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxien-Cluster 1E 0657-Galaxien-Cluster 1E 0657-5656
optisch
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxien-Cluster 1E 0657-Galaxien-Cluster 1E 0657-5656
Röntgen
Christian Stegmann, Cosmology, CERN 2008
Time
GravitationslinsenGravitationslinsen
Christian Stegmann, Cosmology, CERN 2008
Time
Optisch + Röntgen + Dunkle Materie
Christian Stegmann, Cosmology, CERN 2008
Time
Was ist passiert?Was ist passiert?
Christian Stegmann, Cosmology, CERN 2008
Time
Galaxien Cluster CL0024 17Galaxien Cluster CL0024 17Heute