Working from home with my ZZ plant in the background
This is an image of me working from home.
You can see my ZZ plant on top of the cabinet in the background.

Bishal Deb

I am a PhD student in the Mathematics department of University College London (2019 onwards). My supervisor is Alan Sokal.
My primary interest is in enumerative combinatorics. I try to exactly enumerate combinatorial families of objects. I love bijective method of proofs and proof without words.
My PhD research is primarily on totally positive (totally non-negative as per Wikipedia).
You can find my upgrade presentation here. You will notice that I use memes and images, one of which is from Math with Bad Drawings by Ben Orlin.

bishal dot deb dot nineteen at ucl dot ac dot uk

Replace 'dot' and 'at' with the appropriate symbols and 'nineteen' with the two digits used to represent it in decimal notation.

Past education

Master 2 degree in Computer Science, Université Paris-Est Marne-la-Vallée (now Université Gustave Eiffel) in Informatique Fondamentale track (2019). My M2 was funded by Labex Bezout.
Bachelors of Science in Mathematics and Computer Science, Chennai Mathematical Institute (2017)

During my time in CMI, I attended two out of four courses offered by Prof. Xavier Viennot at the Institute of Mathematical Sciences, Chennai. The courses were offered between 2016-2019, one course each year. The lectures have been recorded and uploaded on YouTube. The links can be found on his website. He has arranged it in the form of a video book, where each lecture has been divided into sections and each of their timestamped links from the YouTube video have been linked. The slides are also available.

Masters Thesis

I did my M2 thesis under the supervision of Samuele Giraudo and Matthieu Josuat-Vergès.
The primary object of study were Stammering Tableaux which were introduced in this paper.
After a chapter introducing the basic objects, the thesis consisted of three different chapters, each dealing with a different property related to Stammering Tableaux:
  1. Projection from Stammering Tableaux to Oscillating Tableaux
    We study a projection from stammering tableaux to oscillating tableaux and see some surprising connection to the γ-vectors of Eulerian numbers.
  2. Polynomiality of Average Weights of Stammering Tableaux
    We define a statistic called weight on stammering tableaux and show that the average weight is a polynomial depending on the size of the tableaux and shape of the tableaux.
  3. Stammering Tableaux, Increasing Trees and Stirling Permutations
    We construct a bijection between stammering tableaux and increasing trees and extend it for Stirling permutations and look at some connections with higher order Eulerian numbers.

Papers and Preprints

  1. Coefficientwise total positivity of some matrices defined by linear recurrences, (with Xi Chen, Alexander Dyachenko, Tomack Gilmore, Alan D. Sokal), arXiv preprint
  2. Multimapper: Data Density Sensitive Topological Visualization, (with Ankita Sarkar, Nupur Kumari, Akash Rupela, Piyush Gupta, Balaji Krishnamurthy), 2018 IEEE International Conference on Data Mining Workshops (ICDMW), doi:10.1109/ICDMW.2018.00153
  3. Chromatic Polynomial and Heaps of Pieces, arxiv preprint

Teaching Duties

I am currently a teaching assistant in the Department of Mathematics. This term I am involved with the following: In the past I have done tutorials for first year pure math modules: Analysis 1 and 2 (MATH0003 and MATH0004), Algebra 1 and 2 (MATH0005 and MATH0006). I have also conducted tutorials for Mathematical Methods 3 (MATH0016) and as well as moderated online problem sessions for MATH0016.

Gonit Sora

I have been involved with the web magazine Gonit Sora almost since its creation. The website was started about a decade ago by Manjil Pratim Saikia and Pankaj Jyoti Mahanta while they were both students at Tezpur University. We are bilingual, Manjil handles the English version and Pankaj handles the Assamese Version.

Since July, 2020 we have been organising a webinar series for undergraduate and masters students, mainly for students in Assam. But the response has been overwhelming and we have had students attending from different parts of India and some of the webinars had over 200 participants in the Zoom call and several others watching it live on our Facebook Page.

For any work related to Gonit Sora, please contact me on bishal at gonitsora dot com and if you wish to submit an article for publication, you should send it to editor at gonitsora dot com. Replace 'dot' and 'at' with the appropriate symbols.

Other activities

I play strategy/simulation single-player video games. Recently, I have been playing Factorio.
I also spend a good amount of my time cooking, watching Anime, and I have a great interest in Hindustani Classical music in particular and music in general.

Some links

(Mostly for personal use)
  1. Gonit Sora
  2. Quanta Magazine
  3. Algebraic Combinatorics Online Seminars maintained by Aram Dermenjain
  4. Bhāvanā
  5. UCL Mathematics Postgraduate Student Seminars
  6. Igor Pak's blog
  7. How to write a clear math paper: some 21st century tips by Igor Pak
  8. Sara Billey's Advice Collection
  9. How to get a PhD in a timely fashion by Sara Billey