Marc Kamionkowski

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We present a formalism for analyzing a full-sky temperature and polarization map of the cosmic microwave background. Temperature maps are analyzed by expanding over the set of spherical harmonics to give multi-pole moments of the two-point correlation function. Polarization, which is described by a second-rank tensor, can be treated analogously by expanding(More)
We explore the consequences that follow if the dark energy is phantom energy, in which the sum of the pressure and energy density is negative. The positive phantom-energy density becomes infinite in finite time, overcoming all other forms of matter, such that the gravitational repulsion rapidly brings our brief epoch of cosmic structure to a close. The(More)
A formalism for describing an all-sky map of the polarization of the cosmic microwave background is presented. The polarization pattern on the sky can be decomposed into two geometrically distinct components. One of these components is not coupled to density inhomogeneities. A non-zero amplitude for this component of polarization can only be caused by(More)
We study the effects of substructure in the Galactic halo on direct detection of dark matter, on searches for energetic neutrinos from weakly interacting massive particles (WIMP) annihilation in the Sun and Earth, and on the enhancement in the WIMP annihilation rate in the halo. Our central result is a probability distribution function (PDF) PðÞ for the(More)
In general-relativistic cosmological models, the expansion history, matter content, and geometry are closely intertwined. In this brief paper, we clarify the distinction between the effects of geometry and expansion history on the luminosity distance. We show that the cubic correction to the Hubble law, measured recently with high-redshift supernovae, is(More)
Are there any manifestations of parity violation other than those observed in weak interactions? A map of the cosmic microwave background (CMB) temperature and polarization will provide a new signature of P violation. We examine two classes of P-violating interactions that would give rise to such a signature. The first interaction leads to a cosmological(More)
We compare the rate for elastic scattering of neutralinos from various nuclei with the ux of upward muons induced by energetic neutrinos from neutralino annihilation in the Sun and Earth. We consider both scalar and axial-vector interactions of neutralinos with nuclei. We nd that the event rate in a kg of germanium is roughly equivalent to that in a 10 5-to(More)
We consider the consequences of a neutral dark-matter particle with a nonzero electric and/or magnetic dipole moment. Theoretical constraints, as well as constraints from direct searches, precision tests of the standard-model, the cosmic microwave background and matter power spectra, and cosmic gamma rays, are included. We find that a relatively light(More)