Vallinotto, Alberto, Viel, Matteo, Das, Sudeep, Spergel, David N.
We expect a detectable correlation between two seemingly unrelated quantities: the four point function of the cosmic microwave background (CMB) and the amplitude of flux decrements in quasar (QSO)...
Simulations of the Microwave Sky (2009)
Sehgal, Neelima, Bode, Paul, Das, Sudeep, Hernandez-Monteagudo, Carlos, Huffenberger, Kevin, Lin, Yen-Ting, ...
We create realistic, full-sky, half-arcminute resolution simulations of the microwave sky matched to the most recent astrophysical observations. The primary purpose of these simulations is to test...
Lenses in the forest: cross-correlation of the Lyman-alpha flux with CMB lensing (2009)
Vallinotto, Alberto, Das, Sudeep, Spergel, David N., Viel, Matteo
We present a theoretical estimate for a new observable: the cross-correlation between the Lyman-alpha flux fluctuations in quasar (QSO) spectra and the convergence of the cosmic microwave background...
Observing the Evolution of the Universe (2009)
Aguirre, James, Amblard, Alexandre, Ashoorioon, Amjad, Baccigalupi, Carlo, Balbi, Amedeo, Bartlett, James, ...
How did the universe evolve? The fine angular scale (l>1000) temperature and polarization anisotropies in the CMB are a Rosetta stone for understanding the evolution of the universe. Through detailed...
CMBPol Mission Concept Study: Gravitational Lensing (2008)
Smith, Kendrick M., Cooray, Asantha, Das, Sudeep, Doré, Olivier, Hanson, Duncan, Hirata, Chris, ...
Gravitational lensing of the cosmic microwave background by large-scale structure in the late universe is both a source of cosmological information and a potential contaminant of primordial gravity...
Measuring Distance Ratios with CMB-Galaxy Lensing Cross-correlations (2008)
Das, Sudeep, Spergel, David N.
We propose a method for cosmographic measurements by combining gravitational lensing of the cosmic microwave background (CMB) with cosmic shear surveys. We cross-correlate the galaxy counts in the...
CMB Lensing and the WMAP Cold Spot (2008)
Das, Sudeep, Spergel, David N.
Cosmologists have suggested a number of intriguing hypotheses for the origin of the "WMAP cold spot", the coldest extended region seen in the CMB sky, including a very large void and a collapsing...
Efficient Power Spectrum Estimation for High Resolution CMB Maps (2008)
Das, Sudeep, Hajian, Amir, Spergel, David N.
Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even...
Next Generation Redshift Surveys and the Origin of Cosmic Acceleration (2008)
Acquaviva, Viviana, Hajian, Amir, Spergel, David N., Das, Sudeep
Cosmologists are exploring two possible sets of explanations for the remarkable observation of cosmic acceleration: dark energy fills space or general relativity fails on cosmological scales. We...
A Large Sky Simulation of the Gravitational Lensing of the Cosmic Microwave Background (2007)
Large scale structure deflects cosmic microwave background (CMB) photons. Since large angular scales in the large scale structure contribute significantly to the gravitational lensing effect, a...
Testing a new analytic model for gravitational lensing probabilities (2005)
Das, Sudeep, Ostriker, Jeremiah P.
We study gravitational lensing with a multiple lens plane approach, proposing a simple analytical model for the probability distribution function (PDF) of the dark matter convergence, kappa, for the...
The Dynamical Mixing of Light and Pseudoscalar Fields (2004)
Das, Sudeep, Jain, Pankaj, Ralston, John P., Saha, Rajib
We solve the general problem of mixing of electromagnetic and scalar or pseudoscalar fields coupled by axion-type interactions ${\cal L}_{int} =g_{\phi} \phi \epsilon_{\mu \nu \a \b}F^{\mu \nu}F^{\a...
Probing Light Pseudoscalars with Light: Propagation, Resonance and Spontaneous Polarization (2004)
Das, Sudeep, Jain, Pankaj, Ralston, John P., Saha, Rajib
Radiation propagating over cosmological distances can probe light weakly interacting pseudoscalar (or scalar) particles. The existence of a spin-0 field changes the dynamical symmetries of...