refining the free function of mond
DESCRIPTION
Dark Matter and Alternative Gravities. Refining the free function of MOND. Workshop Program. Day 1: Galaxies and Solar System Day 2: Large Scale and Lensing Day 3: Satellites and Challenges for all theories. Day 1: Galaxies. The acceleration discrepancy problem Large halos of DM - PowerPoint PPT PresentationTRANSCRIPT
Refining the free function of MOND
Workshop Program
Dark Matter
and
Alternative Gravities
Day 1: Galaxies and Solar System
Day 2: Large Scale and Lensing
Day 3: Satellites and Challenges for all theories
Day 1: Galaxies
• The acceleration discrepancy problem
• Large halos of DM
• CDM: Large Scale Structure and best candidate
• Is the missing satellite problem solved?
• How do we solve the cusp problem in CDM?
• Is WDM the solution? (cf. e.g. dSph)
• What about the -WDM cosmological model?
• Wiggles of the rotation curves?
• With DM, how do we explain the « order » encapsulated in the well-known MOND formula? (g/a0) gg = ggN baryons
with (x) = x for x « 1 (MONDian regime) (x) = 1 for x »1 (Newtonian regime)
• Is this going to end as an equivalent of Titus Bode’s law for the solar system?
• If not, could it be the signature of exotic DM somehow interacting with baryons? Are there candidates?
Day 1: Solar System
• Pioneer anomaly: end of gravity as we know it?
• Thermal emission anisotropy of the spacecraft?
• Is acceleration different for different orbits? => Modified Inertia? End of « metric » gravity?
Day 2: Large Scale
• Are massive galaxies at very high redshift a challenge to standard hierarchical model?
• CMB anisotropies: the most serious challenge to any modified gravity theory?
• Galaxy clusters: failure of the MOND formula + lensing of interacting clusters : => surviving « hybrid » theory? (e.g. BSTV)
• Dark Energy: do we know enough about supernovae? (models don’t explode, while they are the only direct evidence)
• Isn’t there too much dark energy in a flat TeVeS Universe, in order to fit supernovae? Running cosmological constant?
• Non-MOND modifications of the left-hand side of Einstein equation? Is unification with DM possible?
Day 2: Lensing
• Is the scatter observed in the lenses gravity vs. lenses baryonic content real, or due to too many uncertainties in the analysis?
• If confirmed, this scatter cannot be fitted by any modified gravity theory
• What about lensing in conformal gravity?
Day 3: Galactic Satellites
• MOND: Dwarf spheroidals need DM if their size is primarily determined by tides, as distant globular clusters are
• Not all internal velocity dispersion profiles of dSph are compatible with the MOND formula (bigger problem than in galaxy clusters)
Day 3: Challenges
• DM: cusps• DM: wiggles of RC’s
• MOND: CMB, galaxy clusters, function (precise M/L could fix and rule TeVeS out)
• E.g. in conformal gravity, how do we handle complex geometries?
• What happens to dynamical friction in any modified gravity theory?
• Can a hybrid theory save e.g. the issue for dSph?
ETC.