Concept illustration · not data
01 / AccretionHow do black holes feed?
Connecting a black hole’s motion through galactic gas to its evolving accretion rate and mass.
The dual-AGN project ↗
Ph.D. student · Physics · Georgia TechAbinash
Abinash
Das.
I study how pairs of supermassive black holes accrete gas, launch jets and shine at radio wavelengths.
Research in progress · 2026A black hole’s
A black hole’s
journey inward.
Follow the secondary through the host galaxy. Its orbit comes from the numerical simulation; the luminous environment is an illustrative rendering.
01 / Following a black-hole pairSimulation in progress
preliminary
preliminary
Orbit of the secondary · primary at the origin · positions in pc
Jet powerlog₁₀ P [erg s⁻¹]
PrimarySecondarybin contains P = 0time [Gyr]
Distance to the centrecylindrical r [pc]
Min–max of all rows in each of 1000 time binstime [Gyr]
- RECORDED TIME
- 1.4010 Gyrrow 47,637 of 633,121
- CYLINDRICAL RADIUS
- 1245.6 pcz = 0.00 pc
- SECONDARY MASS
- 1.11×10⁷ M☉primary 1.10×10⁸ M☉
- SECONDARY JET POWER
- 7.86×10⁴⁰ erg s⁻¹primary 1.04×10⁴¹ erg s⁻¹
0 Gyr · scrub the full 8.783 Gyr record · arrow keys step 0.1 Myr
Jump to
Playback advances a fixed number of simulation steps per second, so the simulated time per second of playback changes along the run and is shown above. Host light, disk glyphs and jet shapes are illustrative. No merger is shown.
From orbital motion to radio emission. Scrub through the orbit of the secondary black hole as it spirals toward the primary in a simulation that is still in progress. The jet shapes and the light of the host galaxy are illustrative. About this figure.
Questions I’m working on
01 — Research highlightsConcept illustration · not data
02 / Relativistic jetsHow is that energy carried away?
Following the connection between accretion, magnetic fields and the power carried by relativistic jets.
Accretion and jet modeling ↗Concept illustration · not an observation
03 / Radio emissionWhat could a telescope see?
Developing synchrotron spectra and predictions for identifying dual AGNs in future radio surveys.
Toward predictions for the ngVLA ↗Project context, funding and contributions +
Radio Modeling of Dual Active Galactic Nuclei · Summer 2026–Present. Co-advisors: David R. Ballantyne (PI) and Tamara Bogdanović (Co-PI). Center for Relativistic Astrophysics, Georgia Institute of Technology.
Supported by NSF AST-2407658, “The Population and Evolution of Dual AGNs at Radio Wavelengths: Predictions for the ngVLA”. Ballantyne is PI and Bogdanović is Co-PI. Existing orbital-evolution calculations and IllustrisTNG host-galaxy properties are inputs to this work; the dynamical-friction orbital solver predates my contribution. My work develops the accretion, jet and radio-emission framework. The three highlights above describe connected research themes within this project, not three completed results.
Selected work
02 — Papers & presentations2026
Peer-reviewed / Optics 7(3), 42
Quantitative Pulse-Shape-Instability Analysis Using 2D-Runs FROG
P. Abdolghader, R. Jafari, A. Das, B. Banerjee, E. P. Duchrist Crews & R. Trebino
Optics 7(3), 42 (2026). doi:10.3390/opt7030042
My contribution
Read the paper ↗: Quantitative Pulse-Shape-Instability Analysis Using 2D-Runs FROG- Co-wrote the paper.
- Wrote and implemented the computational code for the runs analysis of the differences between measured and retrieved FROG traces.
- Worked on the mathematical and analytical proofs in the paper, including Appendix A on the invariance of the weighted runs statistic under time–bandwidth-preserving rescaling.
2025
Course presentation / PHYS 7127, Cosmology and Galaxies, Georgia Institute of Technology
“Rotational Properties of 21 Sc Galaxies with a Large Range of Luminosities and Radii, from NGC 4605 (R = 4 kpc) to UGC 2885 (R = 122 kpc).”
Seminal-paper presentation on the work of V. C. Rubin, W. K. Ford, Jr., and N. Thonnard (1980).
About me.
I’m a Ph.D. student in Physics at the Georgia Institute of Technology and a member of the Center for Relativistic Astrophysics, co-advised by David R. Ballantyne and Tamara Bogdanović.
My current work focuses on the radio emission of dual active galactic nuclei. Before this, I worked on ultrafast optics at Georgia Tech and on intrinsic galaxy alignments and gamma-ray-burst cosmology at the University of Arizona.
Making physics tangible.
Teaching assistance in Principles of Physics II and Modern Optics Laboratory: experiments, group problem solving and hands-on support.
Teaching & serviceCosmic Conundrum
My writing on science, ideas and the questions that keep us looking more closely.
Visit the writing archive ↗About Figure 01 +
Figure 01 plays back the orbit of the secondary black hole from a semi-analytic simulation that is part of ongoing work; the results are preliminary and not yet published. The black holes’ positions, masses and jet powers come from the simulation. The host-galaxy light, the accretion-disk glyphs and the jets’ length, direction and texture are illustrative; jet brightness follows the simulated jet power. Nothing is shown beyond the end of the simulated inspiral.