General Information:    Home   About Me    CV    Contact     ///  Physics Department SUT   Cosmology Group of Sharif University of Technology  

Academic Activities:      Research Interest   Publication   Projects  Collaborators    My Students   Courses    Cosmology    Talks     درس نامه ها

Other Activities:             Science Outreach   Outside Physics    Articles     News    Press    Links    Photo Gallery   فارسی     Հայերէն

My main research topic is the study of the Large Scale Structures (LSS) of the Universe in order to answer the fundamental questions in cosmology such as the cause of the accelerated expansion of the Universe (Dark Energy), the physics of the unseen skeleton of the structures  (Dark Matter) and the scenario that will describe how all this begins (The Physics of the Early Universe).

 In the meantime, I am interested to start learning and doing research in a very fascinating interdisciplinary field known as Astrobiology.

** My students and I have Research Group Meeting on the topics discussed below in details,

Each Saturday @ 17:00 in Information center of Centtral Library (ground floor) of SUT  -  This is the schedule for Fall 2019 **

The above fundamental questions can be studied by Investigation of Large Scale Structures in Universe. In general this can be divided in to two regimes of Linear Structure Formation and Non-Linear Structure formation. (As the Figure below) Note that they are tightly interconnected.

THIS MEANS THAT OUR RESEACH GROUP IS MAINLY DIVIDED IN TWO SUBGROUPS due to DIVISION.

The above fundamnetal questions (Dark energy, Dark Matter and Early Universe)  can be studied in smaller and more detailed questions as shown in the graph below and the list become afterwards:

The Yellow arrow lines shows the possible inter-connection of different fields of research.]

A) LSS & the Accelerated expansion of the Universe

The LSS observations like the distribution of the galaxies, weak gravitational lensing, redshift space distortion, baryon acoustic oscillation and … are observational tools that can probe the deviation from GR in cosmological scales, in order to study the physics of dark energy and gravity.

In this path of research we study the question that how LSS observations can distinguish between DE and MG models .

  Articles related to this area of research are by me with my collaboratores are: 

6) http://arxiv.org/abs/1510.01720

5) http://arxiv.org/abs/1004.3360

4) http://arxiv.org/abs/0912.2410

3) http://arxiv.org/abs/0904.4390

2) http://arxiv.org/abs/0705.0889

1) http://arxiv.org/abs/astro-ph/0701013

 * The Students that have (had) projects on this topic are:

5) Ali Hossein Torkamann Gholami (SUT)        / (M.Sc.)       / (Sep 2014 - Sep 2016)

4) Hasti Khoraminezhad                  (SUT)        / (M.Sc.)       / (Sep 2014 - Sep 2016)

3) Elaheh Hayati                              (Alzahra)    / (M.Sc.)      / (Sep 2012 - Mar. 2015)

2) Farshid Dielami                           (Kharazmi) / (M.Sc.)      / (Sep. 2012 - Feb. 2015)

1) Amir Mollazadeh                         (Kharazmi) / (M.Sc.)      / (Sep. 2011 - Mar. 2014)

B)Dark Matter Substructures

The Standard model of cosmology, based on the hierarchical structure formation is based on the formation of collapsed dark matter structures which they must be host of the baryonic matter. One of the interesting questions in this arena is that what  are the smallest size dark matter substructures? what is the smallest halos that can be the host of a galaxy? And how these questions can be related to the missing satellite problem, Core cusp problem and almost the galactic scale astrophysics?

* Articles related to this area of research are by me with my collaboratores are: 

2) http://arxiv.org/abs/1310.5412

1) http://arxiv.org/abs/1101.5487

* The Students that have (had) projects on this topic are:

1) Ahmad Shamlou                       (Kharazmi) / (M.Sc.)      / (Sep. 2012 - Feb. 2015)

C) The primordial Universe and LSS

The initial condition of the primordial perturbations seems very simple: nearly Gaussian, nearly adiabatic, nearly isotopic and nearly scale invariant. This information comes from the CMB. However the study of the LSS can be used as a new probe to study any deviation from the above conditions in sub-CMB scales.

* Articles related to this area of research are by me with my collaboratores are: 

6) http://arxiv.org/abs/1406.7277

5) http://arxiv.org/abs/1405.7317

4) http://arxiv.org/abs/1308.2874

3) http://arxiv.org/abs/1306.6932

2) http://arxiv.org/abs/1305.0813

1) http://arxiv.org/abs/1303.4368

 * The Students that have (had) projects on this topic are:

 1) Nareg Mirzatuny                      (SUT)           / (M.Sc.)      / (Sep. 2011 - Sep. 2013)

D)Relativistic Cosmology

The propagation of  light in inhomogeneous universe is effected by gravitational lensing, peculiar velocity of the source and observer, Integrated Sachs- Wolfe effect and... .This corrections are defined under the concept of the relativistic cosmology. Studying of these effects will open up new venue to study the nature of dark matter and dark energy.

* Articles related to this area of research are by me with my collaboratores are: 

2) http://arxiv.org/abs/1412.8457

1) http://arxiv.org/abs/1411.7010

E) LSS: dark matter and baryons

One of the interesting questions in Cosmology, is the study of the nonlinear structure formation, the evolution and formation of dark matter halos, the process of hosting the baryonic matter and the relation of dark matter and baryonic matter known as the bias. The study of the distribution of over and under dense regions (voids) using the excursion set theory is one of the areas of interest. Recently we develop a new formalism to study the Excursion set theory known as Matrix formalism.

* Articles related to this area of research are by me with my collaboratores are: 

1) http://arxiv.org/abs/1606.06666

* The Students that have (had) projects on this topic are:

4) Farnik Nikakhtar                  (SUT)     / (B.Sc.)  / (Dec 2015 - ?)

3) Abtin Shahidi                     (SUT)      / (B.Sc.)  / (Feb 2015 - Sep 2016)

2) Mohammadreza Ayromlou  (SUT)      / (M.Sc.)  / (Sep 2014 - Aug 2016)

1) Arghavan Shafiee                 (Alzahra) / (M.Sc.)  / (Sep 2012 - Mar 2015)                                                                                                                          

F)CMB Lensing and Polarization

The structures in front of the last scattering surface, displace the path of the photons from CMB, studying this effect know as CMB lensing is the  one of the promising cosmological observations to know more about matter distribution and the nature of dark matter and dark energy. In the other hand the polarization of the CMB is a new window to study the early universe physics.

* Articles related to this area of research are by me with my collaboratores are: 

2) http://arxiv.org/abs/1511.05534

1) http://arxiv.org/abs/1411.5312

* The Students that have (had) projects on this topic are:

2) Mohammad Ansari (SUT) / (M.Sc.) / (Sep 2015 - ?)

1) Farbod Hassani  (SUT) / (M.Sc.) / (Sep 2014 - 2 August 2016)

G) Astrobiology

The very fundamental question of Are we alone in the Universe? Can be studied in more detailed questions, like the question of finding exoplanets in habitable zones of their planetary system or finding the planetary systems in the habitable zones of galaxy.

* The Students that have (had) projects on this topic are:

1) Elham Eftekhari   (SUT) / (B.Sc.) / (Sep 2014 - Feb. 2015)