what constitutes the dark matter? dr. theo m. nieuwenhuizen institute for theoretical physics...
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What constitutes the dark matter?
Dr. Theo M. Nieuwenhuizen Institute for Theoretical Physics
University of Amsterdam
Sterrenwacht VestaOostzaan, 17-10-2009
Outline
What is dark matter?Where is it located?Two forms of dark matter: Macho’s and/or Wimp’sSearches Solutions
Discovery of dark matter
Rotation of galaxies
Rotation speed nearly independent of location
Andromeda Nebula in Ultraviolet (HST 2009)
p
Planet Distance to sun Rotation speed
Mercurius 0.45 AE 48 km/s
Aarde 1 AE = 92 million mi 30 km/s
Jupiter 5 AE 13 km/s
• In solar system outer planets are slower
• In galaxies there must be matter out of the center
• Where is the dark matter?
Explanantions
• Planets? MACHOs: Massive Astrophysical Compact Halo Objects
• Heavy particles (“cold dark matter”) ?
WIMPs: Weakly Interacting Massive Particles
• Newton’s law is not valid?
• Hydrodynamics, fluid mechanics
Hydrodynamics• 400.000 yr after big bang: plasma becomes gas (hydrogen,
He)• Jeans 1904: formation of proto-clusters
• Gibson 1996: Viscosity leads to fragmentation in gas balls
of a few earth masses• If gas balls coagulate, stars form• Then Jeans cluster becomes visible as globular cluster• Most gas balls cool and freeze, their clusters are invisible
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fall − time =1/ density , diameter = sound − speed ⊗ fall − time, mass =100.000 suns
Carl H. Gibson* 1935
Sir James Hopwood Jeans 1877-1946
100.000.000 Jeans clusters around Galaxy, 149 visible as globular star clusters. Those clusters form the galactic dark matter.
Isothermal density distribution explains the large rotation speeds far from the center
More than 2000 objects with earth Rudy E.mass observed in microlensing Schild *1942
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1/r2
Omega Centauri: Globular star cluster in Milky Way
• Young blue• stars,• older yellow • stars
• Star formation• out of already• present frozen• gas balls took• place in phases
Helix planetary nebula• Star exploded
• Became white dwarf
• Ca 40.000 “cometary knots”
• = proto-gas balls
• Ca 1 earth mass
• Galactic dark matter = gas balls of earth mass: Macho’s
NGC-2623: Two galaxies inside each others dark matter?
Jeans clusters warmed: new stars in young star clusters
• Antennae galaxies:•
Two colliding galaxiescome within each othersdark matter sphere.
• Along their trajectories they transform severalcold Jeans clusters intoyoung globular star clusters.
• Part 2: Cluster dark matter
• Abell 1689 cluster
of galaxies “Nearby” z = 0.184
• Einstein ring
IncompleteEinstein ringat 100/h kpc
Abell 1689Center
Everythingis in circles:Dark Matteracts as crystal ball
IncompleteEinstein ringat 143 kpc
Abell 1689Centrum
Dark Matteracts as crystal ball
right: oldest galaxy 12.8 billion year
• Cluster of galaxies
• Abell 370
Strongest
gravitation lens
20 times
stronger than A1689
Hubble, after last repair May 2009
Description of lensing data of Abell 1689 Th.M. N. ’09: Consider quantum particles (fermions)
in each others gravitation at a certain temperature.
Measure Limousin et al, ApJ 2007
forlocal Tyson and Fischer ApJ 1995
massdensity
distance to center
Neutrinos cause this lensing
• Known particles: proton, electron, neutron, photon• Neutrino “little neutron”: neutral particle• Predicted in 1930 by Wolfgang Pauli• Lightest of all particles (not massless!)
• Mass now predicted with help of Abell 1689 cluster:
• Mass between 0,2 eV and 2 eV will be searched
in Karlsruhe (2012)
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m =1,5 eV = 2,7 • 10−36 kg
Biggest quantum structure in the Universe
normalized density: # neutrino’s per cubic thermal length per degree of freedom
distance to center
N>1: quantum degenerateN=1: transition quantum-classical
At r = 505 kpc = 1.6 million lightyear d = 2r = 3.2 million lightyearThat is pretty large …
IncompleteEinstein ringat 143 kpc
Abell 1689Center
Summary
Two kinds: Oort and Zwicky Dark Matter
• Oort Dark matter:• Dark matter of galaxies is normal matter. Frozen gas balls of
earth mass (MACHO’s) in Jeans clusters of ca 100.000 solar masses.
• Ca 100 million of those clusters in our Galaxy. 149 visible as old globular star cluster.
• Star formation in globular clusters explained: new stars formed out of frozen gas balls that are already present.
• Dwarf galaxy problem (10.000 stars, much dark matter) solved: Jeans cluster with still many frozen gas balls.
Summary• Oort Dark Matter in galaxies
• Zwicky Dark Matter in clusters of galaxies: • “new” particle: neutrino with mass of 1,5 eV (WIMP)
• Many searches for all kinds of heavy particles were in vain: mass = keV, MeV, GeV, TeV, PeV
ADMX, ANAIS, ArDM, ATIC, BPRS, CAST, CDMS, CLEAN, CRESST,CUORE, CYGNUS, (DAMA), DEEP, DRIFT, EDELWEISS, ELEGANTS, EURECA,
GENIUS, GERDA, GEDEON, GLAST, HDMS, IGEX, KIMS, LEP, LHC, LIBRA, LUX, NAIAD, ORPHEUS, PAMELA, PICASSO, ROSEBUD, SIGN, SIMPLE, UKDM, XENON, XMASS, ZEPLIN. DAMIC, FERMI, ICECUBE, VERITAS.
• Neutrino mass between 0,2 eV and 2 eV is searched in Katrin experiment in Karlsruhe (2012).
Gravitational hydrodynamics of large scale structure formationTh. M. N., Carl H. Gibson, Rudy E. Schild
arXiv:0906.5087
Do non-relativistic neutrinos constitute the dark matter?
Th. M. N.
Europhysics Letters 86 (2009) 59001
Psalm 118:22
The stone which the builders refused
is become the head stone of the corner
KArlsruhe TRItium Neutrino Experiments
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