Wilson Ong

Portrait Casual External Tutor in the School of Mathematics and Statistics at the University of Sydney.

Postal address: Mr Wilson Ong
School of Mathematics and Statistics F07
University of Sydney NSW 2006
Email: W.Ong[at]maths.usyd.edu.au
FAX: +61 2 9351 4534

Curriculum Vitae

About Me

I was born and raised in Perth, Western Australia. Both my parents are Chinese, and my Chinese name is 王伟胜. I completed my undergraduate studies at the University of Western Australia, and received my master's degree from the Australian National University. I intend to commence my PhD in late 2012 (at University College London or Cambridge University).


In first semester 2012, I am a tutor for the following:

Research Interests

Broadly speaking, I am interested in Number Theory and Graph Theory.

In my coursework master's thesis I investigate the following conjecture of Hesselholt:

Let K be a complete discrete valuation field of characteristic zero with residue field kK of characteristic p>0. Let L/K be a finite Galois extension with Galois group G and suppose that the extension of residue fields kL/kK is separable. Then the pro-abelian group {H1(G,Wn(OL))}n>0 is isomorphic to zero, where Wn(.) denotes the ring of p-typical Witt vectors of length n.

The conjecture appears in Hesselholt's paper Galois cohomology of Witt vectors of algebraic integers.


  1. W. Ong, C. Yu, and B.D.O. Anderson, Splitting rigid formations, in Proceedings of the 48th IEEE Conference on Decision and Control, December 2009. DOI: 10.1109/CDC.2009.5400859
  2. W. Ong, A simplified proof of Hesselholt's conjecture on Galois cohomology of Witt vectors of algebraic integers, to appear in Bulletin of the Australian Mathematical Society. DOI: 10.1017/S0004972711003315