About Me
I am Tobias Magnusson, a PhD student in mathematics at Chalmers University of Technology in Gothenburg, Sweden.
My major research interest is in the explicit computation of modular forms, and in particular vectorvalued modular forms. I try to apply vectorvalued modular forms to study many generalized types of modular forms, including higher order modular forms and Jacobi forms. My focus on vectorvalued modular forms has given my research a strong flavor of representation theory.
The computational components of my work on modular forms are all present in the Juliapackage ModularForms.jl which has been developed with Martin Raum and Albin Ahlbäck.
I have a strong interest in computer security and cryptography, and I take the Chalmers and GU Security Specialization in conjunction with my PhD studies in mathematics. In this area, I have collaborated on applying hashchain traversal optimization to an Ethereum smart contract. However, I must confess that I feel particularly at home doing lowlevel programming, learning exploit development (e. g. on exploit.education), and completing pentesting CTFs (e. g. on Hack the Box).
Contact
Send me an email: magnusson.tobias <alfakrøll> gmail <dot> com
.
Publications
My primary research output so far consists of (chronological order):
 Cheap and Secure Metatransactions on the Blockchain Using Hashbased Authorisation and Preferred Batchers, joint with William Hughes (primary author), Alejandro Russo, and Gerardo Schneider (submitted)
 On the Computation of General Vectorvalued Modular Forms, joint with Martin Raum (submitted, arXiv)
 Eichler integrals and generalized second order Eisenstein series, joint with Martin Raum and Albin Ahlbäck (submitted, arXiv)
Minor projects
Some minor things that I have been working on recently:
 Secret sharing with Modular Forms^{1}
 Solutions to challenges on exploit.education. This is still a work in progress.
 Walkthroughs of “Hack the Box” machines. (Here’s
Shield
.)  Fourpart lecture series on false sharing, accompanying “High Performance Computing in C”
 focus_wacom
You can find my config files here.
Education
 2018/08 — present: PhD in Mathematics, Chalmers University of Technology, Gothenburg, Sweden
 2018/01 — 2018/06: Graduate studies in Symbolic Computation, Research Institute for Symbolic Computation, Linz, Austria
 2016/08 — 2017/12: MSc in Mathematics, KTH Royal Institute of Technology and Stockholm University, Stockholm, Sweden
 2015/08 — 2016/06: BSc in Mathematics, Chalmers University of Technology and Gothenburg University, Gothenburg, Sweden
 2009/08 — 2013/12: Courses in Computer Engineering, Lund University, Lund, Sweden
Experience
 2018/08 — present: TA at Chalmers University of Technology and Gothenburg University, Gothenburg, Sweden
 2017/01 — 2017/12: TA at Stockholm University, Stockholm, Sweden
 2015/01 — 2015/06: Primary school teacher in Mathematics, Sommarhemsskolan, Uddevalla, Sweden
 2014/02 — 2014/10: ESL teacher, 城市花园幼儿园 (pīnyīn: Chéngshì huāyuán yòuéryuán, en: City Garden Preschool), 云浮 (pīnyīn: Yúnfú), 广东 (pīnyīn: Guǎngdōng), China
Teaching
At Chalmers I have taught as TA (ordered by hours spent, highest first):
 High Performance Computing in C
 Multidimensional Calculus for Engineers
 Programming in Matlab
 Numerical Analysis and Linear Algebra (with Matlab)
 Programming in Python
At Stockholm University, I taught as TA (ordered as above):
 Mathematics I
 Preparatory Course in Mathematics
Languages and tools
It is important for me to be flexible in which tools I use, but my current workflow is based on:
 nvim for editing,
 make for building,
 LaTeX for writing papers^{2},
 Arch Linux as OS with i3gaps as window manager,
 vifm for file management,
 gdb for debugging and exploit development,
 C as primary language,
 Julia as secondary language (for research),
 Python as “drafting” language, and
 Matlab when teaching engineers.
When completing CTFs, I also use Wireshark.
As for natural languages, I speak Swedish, English, conversational German, and basic Mandarin.

The code uses SageMath, because it has a more stable version of scalarvalued modular forms over finite fields. ↩︎

I dabbled with plain TeX for a while, as a real programmer should. I would not recommend it. ↩︎