J-PAS: The Javalambre-Physics of the Accelerated Universe Astrophysical Survey
- N. Benı́tez, R. Dupke, L. Valdivielso
- Physics
- 20 March 2014
The Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) is a narrow band, very wide field Cosmological Survey to be carried out from the Javalambre Observatory in Spain with a…
Exploring the expanding Universe and dark energy using the statefinder diagnostic
- Ujjaini Alam, V. Sahni, T. D. Saini, A. Starobinsky
- Physics
- 1 March 2003
The coming few years are likely to witness a dramatic increase in high-quality supernova data as current surveys add more high-redshift supernovae to their inventory and as newer and deeper supernova…
Statefinder—A new geometrical diagnostic of dark energy
- V. Sahni, T. D. Saini, A. Starobinsky, Ujjaini Alam
- Physics, Computer Science
- 30 January 2002
It is demonstrated that the Statefinder diagnostic can effectively differentiate between different forms of dark energy and can be determined to very high accuracy from a SNAP-type experiment.
RECONSTRUCTING DARK ENERGY
- V. Sahni, A. Starobinsky
- Physics
- 2 October 2006
This review summarizes recent attempts to reconstruct the expansion history of the universe and to probe the nature of dark energy. Reconstruction methods can be broadly classified into parametric…
Shapefinders: A New Shape Diagnostic for Large-Scale Structure
- V. Sahni, B. Sathyaprakash, S. Shandarin
- Physics
- 7 January 1998
We construct a set of shapefinders used to determine the shapes of compact surfaces (isodensity surfaces in galaxy surveys or N-body simulations) without fitting them to ellipsoidal configurations,…
Statefinder hierarchy: An extended null diagnostic for concordance cosmology
- M. Arabsalmani, V. Sahni
- Physics
- 18 January 2011
We show how higher derivatives of the expansion factor can be developed into a null diagnostic for concordance cosmology ({Lambda}CDM). It is well known that the Statefinder - the third derivative of…
Is cosmic acceleration slowing down
- A. Shafieloo, V. Sahni, A. Starobinsky
- Physics
- 30 March 2009
We investigate the course of cosmic expansion in its recent past using the Constitution SN Ia sample, along with baryon acoustic oscillations (BAO) and cosmic microwave background (CMB) data.…
The Case for a positive cosmological Lambda term
- V. Sahni, A. Starobinsky
- Physics
- 28 April 1999
Recent observations of Type 1a supernovae indicating an accelerating universe have once more drawn attention to the possible existence, at the present epoch, of a small positive Lambda-term…
Two new diagnostics of dark energy
- V. Sahni, A. Shafieloo, A. Starobinsky
- Physics
- 23 July 2008
We introduce two new diagnostics of dark energy (DE). The first, Om, is a combination of the Hubble parameter and the cosmological redshift and provides a null test of dark energy being a…
Refining inflation using non-canonical scalars
- S. Unnikrishnan, V. Sahni, A. Toporensky
- Physics
- 3 May 2012
This paper revisits the Inflationary scenario within the framework of scalar field models possessing a non-canonical kinetic term. We obtain closed form solutions for all essential quantities…
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