CMB Lensing Constraints on Neutrinos and Dark Energy (2009)
De Putter, Roland, Zahn, Oliver, Linder, Eric V.
Signatures of lensing of the cosmic microwave background radiation by gravitational potentials along the line of sight carry with them information on the matter distribution, neutrino masses, and...
Being PC: Principal Components and Dark Energy (2008)
De Putter, Roland, Linder, Eric V.
Principal component analysis is considered as an addition to the well-tested parametrization w(a)=w_0+w_a(1-a) for the dark energy equation of state. This brief note cautions against some unjustified...
Calibrating Dark Energy (2008)
De Putter, Roland, Linder, Eric V.
Exploring the diversity of dark energy dynamics, we discover a calibration relation, a uniform stretching of the amplitude of the equation of state time variation with scale factor. This defines...
Field Flows of Dark Energy (2008)
Cahn, Robert N., De Putter, Roland, Linder, Eric V.
Scalar field dark energy evolving from a long radiation- or matter-dominated epoch has characteristic dynamics. While slow-roll approximations are invalid, a well defined field expansion captures the...
To Bin or Not To Bin: Decorrelating the Cosmic Equation of State (2007)
De Putter, Roland, Linder, Eric V.
The physics behind the acceleration of the cosmic expansion can be elucidated through comparison of the predictions of dark energy equations of state to observational data. In seeking to optimize...
Kinetic k-essence and Quintessence (2007)
De Putter, Roland, Linder, Eric V.
Dark energy models with non-canonical kinetic energy terms, k-essence, can have dynamical and sound speed properties distinct from canonical scalar fields, quintessence. Concentrating on purely...
Effective non-intercommutation of local cosmic strings at high collision speeds (2006)
Achucarro, Ana, De Putter, Roland
We present evidence that Abrikosov-Nielsen-Olesen (ANO) strings pass through each other for very high speeds of approach due to a double intercommutation. In near-perpendicular collisions numerical...
Using Weak Lensing to find Halo Masses (2004)
De Putter, Roland, White, Martin
Since the strength of weak gravitational lensing is proportional to the mass along the line of sight, it might be possible to use lensing data to find the masses of individual dark matter clusters....