Current students

We hope you are enjoying your time in our graduate programs. Check out our course offerings, information about degree completion, the PhD qualifying exams, the PhD lecturing requirement, and instructions on submitting your PhD annual activity report. If you still have some years ahead in your grad studies, you might be interested in applying for scholarships.

If you have any administrative questions, please contact us at cograd@uwaterloo.ca.

Seminars in Combinatorics and Optimization

Wednesday, November 19, 2025 10:30 am - 11:30 am EST (GMT -05:00)

Crypto Reading Group -Roy Stracovsky

Title:Enhancing Anamorphic Cryptography

Speaker Roy Stracovsky
Affiliation Georgia Tech
Location MC 5479

Abstract: Anamorphic cryptography (Persiano, Phan, and Yung, Eurocrypt 2022) allows users who share a “double key” to hide encrypted messages in ciphertexts and signatures to allow covert communication under a hypothetical “dictator” who can monitor all communication or force parties to give up their cryptographic keys in order to check for compliance.

In this talk, I will present joint work with Joseph Jaeger which enhances the security and functionality of anamorphic cryptography. We first enhance the security of anamorphic signatures by proposing two parallel notions of unforgeability (against the aforementioned dictator or instead a recipient) which close gaps in existing definitions termed robustness (Banfi, Gegier, Hirt, Maurer, and Rito, Eurocrypt 2024) and private anamorphism (Kutylowski, Persiano, Phan, Yung, and Zawada, Crypto 2023). Previously proposed anamorphic schemes do not necessarily achieve our new definitions but can sometimes be made to do so by modifying the scheme or by leveraging stronger assumptions on the underlying building blocks.
For our second enhancement, we introduce techniques to stealthily exchange keys via anamorphic cryptosystems, allowing covert communication between users that do not a priori share a double key. We propose and analyze multiple protocols in a four-quadrant security model capturing passive versus active adversaries who may or may not perform key compromise.
Thursday, November 27, 2025 2:30 pm - 3:30 pm EST (GMT -05:00)

Algebraic and enumerative combinatorics seminar-Zeus Dantas E Moura

Title: Algebraic and enumerative combinatorics seminar

Speaker Zeus Dantas E Moura
Affiliation University of Wtaerloo
Location MC 6029

Abstract:

Permuted-basement Macdonald polynomials E_α^σ(x_1, ..., x_n; q, t) are nonsymmetric generalizations of symmetric Macdonald polynomials indexed by a composition α and a permutation σ. They can be described combinatorially as generating functions over augmented fillings of shape α and basement σ.

We construct deterministic and probabilistic bijections on fillings that prove identities relating

E_α^σ, E_α^{σ s_i}, E_{s_i α}^σ, and E_{s_i α}^{σ s_i}.

These identities arise from two operations on the shape and basement: swapping adjacent parts of the shape, which expands

E_α^σ intoE_{s_i α}^σ and E_{s_i α}^{σ s_i}; and swapping adjacent basement entries,

which gives E_α^σ = E_α^{σ s_i} when α_i = α_{i+1}.

There will be a pre-seminar presenting relevant background at the beginning graduate level starting at 1:30pm.