1108.2517
Weak Primordial Magnetic Fields and Anisotropies in the CMB Radiation
Jedamzik, Abel
* new tewt of primoridal magnetic fields using the CMB. Induces small scale but large baryon inhomogeneities. The RMS shift in recombination history would change in the CMB in a detectable way. Lowers the detection limit on primordial B-fields by at least 100-fold. (down to 1e-11G)
Small-scale magnitic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the universe (does it make ionization more inhomogeneous?), which in turn decrease the angular scale of the Doppler peaks (why?) and increases Silk damping by photon diffusion.
1108.3080
How unitary cosmology generalizes the thermodynamics and solves the inflationary entropy problem
Tegmark
* quantum entanglement: a form of quantum superposition, whose state is indefinite until a measurement is made. When a measurement is made on one member of the two initially interacting but subsequently separated pair, then the other member of this pair (the entangled pair) will take on a definite value. Verified experimentally.
2nd law of thermodynamics : "The system's entropy cannot decrease unless it interacts with the observer; cannot increase unless it interacts with the environment." Long-range entanglement created by cosmological inflation causes the cosmic entropy to decrease exponentially rather than linearly with the number of bits of information observed. Whatever.
1108.3332
Central Powering of the largest Lyman-alpha Nebula is revealed by polarized radiation
Hayes, Scarlata, Siana
* Lyman-alpha blob (LAB): a huge concentration of gas emitting the Ly-a emission line, generated by recombination of electrons with ionized hydrogen atoms.
High-z Lyman-alpha blobs: extended, luminous, rare structures; appears to be associated with the highest peaks in the matter density of the universe. Energy output an morphology similar to powerful radio galaxies, but source of luminosity unclear. Some seem to be associated with extreme starburst, while another possibility is gas that is shock-excited by supernovae. Some blobs not associated with galaxies, and could be heated by gas falling into a DM halo. Have detected polarization from LAB1: centralregions show no measurable polarization, while the polarization fraction increase to 20% at radius 45 kpc, formng an almost complete polarized ring. The detection of polarized radiation is inconsistent with the in situ production of Ly-a photons, and so the conclusion is that they must have been produced in the galaxies hosted within the nebula, and re-scattered by neutral H. (So the starburst scenario, eh?)
1108.3697
Using dwarf satellite proper motions to determine their origin
Angus, Diaferio, Kroupa
It's kinda hard to get these dwarf galaxies around MW to come in from a filament, given their current proper motion and assumed dynamical friction.
1108.3717
Halo shapes from WL: the impact of Galaxy-halo misalignment
Bett
Need quite a bit of galaxy-halo alignment for the halo shape to show in stacked gg-lensing analysis.
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