Dr Allan Lo MA MMath PhD

Contact details

Email: s.a.lo@bham.ac.uk

Address: School of Mathematics
Watson Building
University of Birmingham
Edgbaston
Birmingham
B15 2TT
UK

Allan Lo is a Senior Lecturer, whose research interests lie primarily in combinatorics, in particular, in extremal graph theory and hypergraphs. He is currently investigating Ramsey-type problems in hypergraphs.

Personal webpage.

Qualifications

MMath in Mathematics, Cambridge, 2011
PhD in Mathematics, University of Cambridge, 2010
MA in Mathematics, University of Cambridge, 2006
BA in Mathematics, University of Cambridge, 2005

Biography

Allan Lo received his PhD degree from the University of Cambridge in 2010 under the supervision of Professor Andrew Thomason. He was a postdoctoral position at Umeå University, Sweden. He then joined School of Mathematics at the University of Birmingham in 2011 as a research fellow. In 2014, he became a Birmingham Fellow. He became a Senior Lecturer since 2019.

Teaching

Semester 1

LH/LM Combinatorics and Communication Theory

Semester 2

LI/LH Algebra and Combinatorics 2

Postgraduate supervision

Allan Lo is happy to hear from any students who are interested in PhD study in Combinatorics.

Research

Research themes

Combinatorics, especially Extremal Graph Theory and Hypergraphs and Ramsey Theory

Research activity

The main research area of Allan Lo is Combinatorics. He has worked on extremal graph theory, hypergraphs and Ramsey theory.

For example, he studied edge-decomposition of graphs. Typical questions in this field also arise from considering scheduling problems, a famous recreational example being Kirkman's schoolgirl problem which dates back to 1850 and asks for an assignment of 15 schoolgirls into groups of three on seven different days such that no two schoolgirls are allocated to the same group more than once.

This particular problem is easy to solve, and its solution is the simplest example of a Steiner triple system or, more generally, a combinatorial design. More general constructions of such combinatorial designs are often based on geometric and algebraic concepts such as projective planes and Hadamard matrices.

Publications

Recent publications

Article

Lo, A & Pfenninger, V 2024, 'Almost partitioning every 2-edge-coloured complete k-graph into k monochromatic tight cycles', Innovations in Graph Theory, vol. 1, pp. 1-19. https://doi.org/10.5802/igt.1

Bal, D, DeBiasio, L & Lo, A 2024, 'A lower bound on the multicolor size-Ramsey numbers of paths in hypergraphs', European Journal of Combinatorics, vol. 120, 103969. https://doi.org/10.1016/j.ejc.2024.103969

Lo, A, Piga, S & Sanhueza Matamala, N 2024, 'Cycle decompositions in k-uniform hypergraphs', Journal of Combinatorial Theory. Series B, vol. 167, pp. 55-103. https://doi.org/10.1016/j.jctb.2024.02.003

Lo, A, Patel, V & Yildiz, MA 2024, 'Hamilton cycles in dense regular digraphs and oriented graphs', Journal of Combinatorial Theory. Series B, vol. 164, pp. 119-160. https://doi.org/10.1016/j.jctb.2023.09.004

Boyadzhiyska, S & Lo, A 2024, 'Ramsey goodness of k-uniform paths, or the lack thereof', European Journal of Combinatorics. https://doi.org/10.1016/j.ejc.2024.104021

Lo, A & Pfenninger, V 2024, 'The Ramsey Number for 4-Uniform Tight Cycles', SIAM Journal on Discrete Mathematics. https://doi.org/10.48550/arXiv.2111.05276

Ferra Gomes De Almeida Girao, AJ, Granet, B, Kuhn, D, Lo, A & Osthus, D 2023, 'Path decompositions of tournaments', Proceedings of the London Mathematical Society. https://doi.org/10.1112/plms.12480

Glock, S, Kuhn, D, Lo, A & Osthus, D 2023, 'The Existence of Designs via Iterative Absorption: Hypergraph F-Designs for Arbitrary F', Memoirs of the American Mathematical Society, vol. 284, no. 1406, pp. 1-144. https://doi.org/10.48550/arXiv.1611.06827, https://doi.org/10.1090/MEMO/1406

Lo, A & Pfenninger, V 2023, 'Towards Lehel's conjecture for 4-uniform tight cycles', Electronic Journal of Combinatorics, vol. 30, no. 1, P1.13. https://doi.org/10.37236/10604

Day, N & Lo, A 2023, 'Upper density of monochromatic paths in edge-coloured infinite complete graphs and bipartite graphs', European Journal of Combinatorics, vol. 110, 103625. https://doi.org/10.1016/j.ejc.2022.103625

Lo, A, Treglown, A & Zhao, Y 2022, 'Complete subgraphs in a multipartite graph', Combinatorics, Probability and Computing, vol. 31, no. 6, pp. 1092-1101. https://doi.org/10.1017/S0963548322000141

Conference contribution

Lo, A & Pfenninger, V 2023, Almost partitioning every 2-edge-coloured complete k-graph into k monochromatic tight cycles. in EUROCOMB’23., 100, European Conference on Combinatorics, Graph Theory and Applications, no. 12, Masaryk University Press, pp. 1-6, European Conference on Combinatorics, Graph Theory and Applications, Prague, Czech Republic, 28/08/23. https://doi.org/10.5817/CZ.MUNI.EUROCOMB23-100

Lo, A, Patel, V & Yildiz, MA 2023, Cycle Partition of Dense Regular Digraphs and Oriented Graphs. in EUROCOMB’23., 99, European Conference on Combinatorics, Graph Theory and Applications, no. 12, Masaryk University Press, pp. 1-8, European Conference on Combinatorics, Graph Theory and Applications, Prague, Czech Republic, 28/08/23. https://doi.org/10.5817/CZ.MUNI.EUROCOMB23-099

Boyadzhiyska, S & Lo, A 2023, Tight path, what is it (Ramsey-) good for? Absolutely (almost) nothing! in EUROCOMB’23., 26, European Conference on Combinatorics, Graph Theory and Applications, no. 12, Masaryk University Press, pp. 1-7, European Conference on Combinatorics, Graph Theory and Applications, Prague, Czech Republic, 28/08/23. https://doi.org/10.5817/CZ.MUNI.EUROCOMB23-026

Review article

Freschi, A & Lo, A 2024, 'An oriented discrepancy version of Dirac's theorem', Journal of Combinatorial Theory. Series B, vol. 169, pp. 338-351. https://doi.org/10.1016/j.jctb.2024.06.008

View all publications in research portal