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The Universe
What do we know about it age: 14.6 billion years Evolved from Big Bang chemical composition
Structures in the universe galaxy clusters galaxies voids
Separation of forces
gravity strong force weak force
what causes interaction?
gravity
electromagnetism
weak force
strong force
Some particle physics
Baryons: composed of three quarks
Mesons: composed of one quark and one antiquark
Baryons and mesons: hadrons Hadrons are composed of quarksstrong
interaction Leptons: no quarks, no strong
interaction
proton; the only long living hadron, t=1031s; measure for p decay= test for GUT
Higgs particle, higgs field mass=interaction of a particle In empty space, the Higgs field has an
amplitude different from zero; i.e., a non-zero vacuum expectation value.
The existence of this non-zero vacuum expectation plays a fundamental role: it gives mass to every elementary particle which has mass, including the Higgs boson itself.
GalaxiesClusters
what cause
s stru
cture
in th
e
univers
e?
Das galaktische Zentrum
La voie lactee
The solar neighborhood
Galaxis
200-400 109 SterneDurchm.: 100 000 LjRotation: Ort der Sonneetwa 200 Mill Jahre
Determination of the mass of a galaxy
2
2
r
MmG
r
vm
Galactic center
Star
attractioncentrigual force
Solarsystem…
Merkury: 88 daysEarth: 1 yearJupiter: 11,6 years…
Galactic rotation curve
v (R)
Kepler
Rotation of a galaxy
Rotation curve of NGC 3198
merde
Gravity lensing
Composite image of the Bullet cluster shows distribution of ordinary matter, inferred from X-ray emissions, in red and total mass, inferred from gravitational lensing, in blue.
properties of dark matter undetectable by radiation detectable only by gravitation
rotation of galaxies orbital velocities of galaxies in cluster of
galaxies gravitational lensing temperature distribution of hot gas in
galaxies and clusters of galaxies
what is dark matter made of majority: non baryonic non baryonic matter
neutrinos axions supersymmetric particles does not contribute to the formation of
elements in the cosmos
non baryonic matter
hdm hot dark matter: massive neutrinos
cdm cold dark matter: will lead to a bottom up formation of structure in the universe; neutralino
wdm warm dark matter
Neutralinos
big bang: neutralino halos mass of Earth, size equal to the solar
system can be detected:
disturb Oort cloud cometary showers produce gamma ray bursts when
colliding more probable near galactic center
baryonic matter
composed of baryons protons neutrons
candidates for baryonic dark matter MACHOs: massive astropnomical
compact halo objects brown dwarfs (M<0.08 MSun
amount can be calculated from big bang nucelosynthesis cosmic microwave background
MACHOS
Detect: gravity bends light MACHO may be detected if it pass in
front of a star or nearby a star; brightening of the star
candidates for MACHOS black holes neutron stars black dwarfs
WIMPS weakly interacting massive particles interact through weak force and
gravity do not interact through
electromagnetism large mass, slow moving, cold
particles could interact with the Sun, produce
high energy neutrinos
CDMS cryogenic dark matter search
RAMBOs Robust associations of massive baryonic objects
dark cluster made of white dwarfs brown dwarfs
radii: 1 pc … 15 pc
supersymmetry, susy
In particle physics, supersymmetry (often abbreviated SUSY) is a symmetry that relates elementary particles of one spin to other particles that differ by half a unit of spin and are known as superpartners.
In a theory with unbroken supersymmetry, for every type of boson there exists a corresponding type of fermion with the same mass and internal quantum numbers, and vice-versa.
Λ CDM Model of Cosmology I Λ cosmological constant associated
with a vacuum energy or dark energy explains the current accelerating
expansion of space against the attractive (collapsing) effects of gravity. ΩΛ, which is interpreted as the fraction of the total mass-energy density of a flat universe that is attributed to dark energy.
Currently, about 74% of the energy density of the present universe is estimated to be dark energy.
Λ CDM Model of Cosmology II CDM cold dark matter dark matter is described as
cold (non relativistic) collisionless (only gravity forces) 22% of the mass-energy density of the
universe
quantum chromodynamics describes strong interaction
