I am a part time visiting scientist at Berkeley Center for Cosmological Physics. I develop and maintain the software stack that supports research in Cosmology.

I develop a lot of software packages, and contributes to many more. Most of these can be found at my github page. In earlier days I was involved with GNOME2 with a side-line project gnome-globalmenu; I do not think many people still use it; as the features have been partially included in GNOME3 and Ubuntu Unity.

My work in cosmolgoy spans three fields:

  • massively parallel super-computing applications, and

  • methods and software tools for data analysis;

Please refer to my list of publications.

Here is a list of research topics and projects that I have contributed to:

  • Cosmology

    • Large Scale Structure (LSS) and perturbation theory; 5 7 18 8

    • Formation of galaxies, galaxy clusters, star-formation models and super-massive blackholes. 2 1 3 4

    • Weak lensing and intrinsic alignments. 6

    • Reduction of imaging data from imaging surveys. 22

  • Super-computing Applications

    • Solver for cosmological hydrodynamics; 9

    • Parallel Fast Fourier Transformation; 10

    • Massively parallel sorting; 11

    • Efficient launching of Python applications on super-computers; 12

  • Software and methods for data analysis

    • Automated differentiation 20

    • Optimization beyond first order 21

    • Parallel data analysis of N-body simulations 13

    • In-node Map-Reduce via Multi-processing 17

    • Hierarchical Data Format for large data sets 19

    • KD-tree, pair-wise counting and Friends-of-Friends 14 15

    • Visualization of smoothed particle field 16

I was part of several largest cosmological simulations. These simulations required some of the largest super-computers today(or then), running at their full capability for days; that's hundreds of millions of CPU-hours. We do make important predictions about blackholes and galaxies with these simulations.

1

High-redshift supermassive black holes: accretion through cold flows. http://adsabs.harvard.edu/abs/2014MNRAS.440.1865F

2

Cold Flows and the First Quasars. http://adsabs.harvard.edu/abs/2012ApJ...745L..29D

3

The MassiveBlack-II simulation: the evolution of haloes and galaxies to z ˜ 0 . http://adsabs.harvard.edu/abs/2015MNRAS.450.1349K

4

The Formation of Milky Way–mass Disk Galaxies in the First 500 Million Years of a Cold Dark Matter Universe. http://adsabs.harvard.edu/abs/2015ApJ...808L..17F

5

Mock Quasar-Lyman-α forest data-sets for the SDSS-III Baryon Oscillation Spectroscopic Survey. http://adsabs.harvard.edu/abs/2015JCAP...05..060B

6

Intrinsic alignments of galaxies in the MassiveBlack-II simulation: analysis of two-point statistics. http://adsabs.harvard.edu/abs/2015MNRAS.448.3522T

7

Eulerian BAO Reconstructions and N-Point Statistics. http://adsabs.harvard.edu/abs/2015arXiv150806972S

8

Perturbation theory, effective field theory, and oscillations in the power spectrum http://adsabs.harvard.edu/abs/2015arXiv150902120V

9

http://bluetides-project.org/coderelease/

10

Python binding of a library for massively Parallel Fast Fourier Transform (PFFT). http://github.com/rainwoodman/pfft-python

11

A library for parallel histogram sort with a Python binding. https://github.com/rainwoodman/MP-sort

12

Boosting python start-up speed with MPI. https://github.com/rainwoodman/python-mpi-bcast

13

Parallel Data Analysis for N-body simulations. http://github.com/bccp/nbodykit

14

Spatial data with a KD-tree. http://github.com/rainwoodman/kdcount

15

Scipy cKDTree rewrite (pending, https://github.com/sturlamolden/scipy/pull/1)

16

http://github.com/rainwoodman/gaepsi

17

http://github.com/rainwoodman/sharedmem

18

A pure particle mesh solver. http://github.com/rainwoodman/fastpm

19

Hierarchy Data Files. http://github.com/rainwoodman/bigfile

20

A simple autodiff and a small library of operators. http://github.com/rainwoodman/vmad

21

(ABstract OPTimizer) - optimization of generic numerical models. http://github.com/bccp/abopt

22

http://desi.lbl.gov