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What constitutes the dark matter?

What constitutes the dark matter?. Dr. Theo M. Nieuwenhuizen Institute for Theoretical Physics University of Amsterdam. Sterrenwacht Vesta Oostzaan, 17-10-2009. Outline. What is dark matter? Where is it located? Two forms of dark matter: Macho’s and/or Wimp’s Searches Solutions.

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What constitutes the dark matter?

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  1. What constitutes the dark matter? Dr. Theo M. Nieuwenhuizen Institute for Theoretical PhysicsUniversity of Amsterdam Sterrenwacht Vesta Oostzaan, 17-10-2009

  2. Outline What is dark matter? Where is it located? Two forms of dark matter: Macho’s and/or Wimp’s Searches Solutions

  3. Discovery of dark matter • 1931 Jan Oort Leiden: motions in our galaxy are “too fast” • perpendicular to galactic plane: stars should escape • In the plane: stars should escape from their elliptic orbit • Explanation: there is more matter than we see: dark matter • 1900 - 1992 • 1932 Fritz Zwicky: clusters of galaxies • They rotate too fast around each other • Explantion: dark matter • 1898 - 1974

  4. Rotation of galaxies Rotation speed nearly independent of location

  5. Andromeda Nebula in Ultraviolet (HST 2009)

  6. p • In solar system outer planets are slower • In galaxies there must be matter out of the center • Where is the dark matter?

  7. 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

  8. 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

  9. Sir James Hopwood Jeans 1877-1946 Carl H. Gibson* 1935 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

  10. 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

  11. 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

  12. NGC-2623: Two galaxies inside each others dark matter? Jeans clusters warmed: new stars in young star clusters

  13. Antennae galaxies: • Two colliding galaxiescome within each othersdark matter sphere. • Along their trajectories they transform severalcold Jeans clusters intoyoung globular star clusters.

  14. Part 2: Cluster dark matter • Abell 1689 cluster of galaxies “Nearby” z = 0.184 • Einstein ring

  15. Incomplete Einstein ring at 100/h kpc Abell 1689 Center Everything is in circles: Dark Matter acts as crystal ball

  16. Incomplete Einstein ring at 143 kpc Abell 1689 Centrum Dark Matter acts as crystal ball right: oldest galaxy 12.8 billion year

  17. Hubble, after last repair May 2009 • Cluster of galaxies • Abell 370 Strongest gravitation lens 20 times stronger than A1689

  18. 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 for local Tyson and Fischer ApJ 1995 mass density distance to center

  19. 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)

  20. Biggest quantum structure in the Universe normalized density: # neutrino’s per cubic thermal length per degree of freedom distance to center N>1: quantum degenerate N=1: transition quantum-classical At r = 505 kpc = 1.6 million lightyear d = 2r = 3.2 million lightyear That is pretty large …

  21. Incomplete Einstein ring at 143 kpc Abell 1689 Center

  22. 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.

  23. 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). Summary

  24. Gravitational hydrodynamics of large scale structure formationTh. M. N., Carl H. Gibson, Rudy E. SchildarXiv:0906.5087 Do non-relativistic neutrinos constitute the dark matter? Th. M. N. Europhysics Letters 86 (2009) 59001

  25. Psalm 118:22 The stone which the builders refused is become the head stone of the corner

  26. KArlsruhe TRItium Neutrino Experiments

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