Dexter Chua

About Me

I was a PhD student at Harvard between 2018 and 2022. Previously, I did my undergraduate and Part III at Cambridge (2014–2018).

Contact Me

You can email me at

Adams Spectral Sequence for tmftmf

I have documented the calculation of the Adams spectral sequence of tmftmf at the prime 22 here (warning: this downloads a 12MB file behind the scenes).

This calculation was made with computer assistance. There is an online version of the software, and the source can be found on GitHub. See the README on GitHub for technical details.

The software computes the E2E_2 page and products, and propagates differentials via the Leibniz rule. The program is capable of resolving an arbitrary (finite dimensional or finitely generated) Steenrod module and assisting the computation of the associated Adams spectral sequence. It is also designed with the intention to be able to aid other spectral sequence calculations (as long as the modules are over Fp\mathbb{F}_p), but no such applications have been coded at the moment. It was initially developed by Hood Chatham and I later joined the development.

The save file for the calculation can be found here, which can be imported into the resolver to reproduce the calculation. (However, doing it on the online version above is unwise)

Steenrod operations

Using an algorithm of Christian Nassau, I calculated some Steenrod operations in Ext of the Steenrod algebra and A(2)A(2). The results are documented here, and they go beyond what is in Bruner's tables.

Expository Writings

Some miscellaneous expository writings. The word "expository" refers to the lack of originality, as opposed to any claim of comprehensibility or correctness.

Clicking the title below will lead to a web version of the note, which is an experimental feature — let me know if anything seems broken. Click "pdf" for a downloadable pdf version.

Cambridge Course Notes

When I was in Cambridge, I typed up my lecture notes for the courses I attended. They can be found here.

Computer Drawings

As a means of procrastination learning how to use HTML5 canvas, I produced the following drawings/simulations:

Grid paper

I wrote a web page that produces grid papers. The source code is available on GitHub. Feature requests are welcome.

PDF Cropping

I also wrote a web page that helps you crop PDFs with a specified aspect ratio. Feature requests and bug reports are welcome.


Other Involvements

I co-organized the Bott periodicity seminar during Spring 2019.

I have been on the committee of the Cambridge student societies The Archimedeans, CUPS, the SRCF and the RCSA. I am also a sysadmin of the SRCF.

Privacy Statement

I have a Privacy Statement as required by law (maybe).