Research

My research spans various areas of theoretical computer science.

In cryptography, I currently focus on both foundations and the design of efficient Zero-Knowledge Proofs.

In computational complexity, I am particularly interested in understanding the complexity class TFNP of total NP search problems.

A significant part of my work explores the bridge between game theory and cryptography, designing and analyzing protocols with security against utility-maximizing agents.

Preprints

• M. Balko, J. Grebík, P. Hubáček, M. Koutecký, M. Kripner, V. Rozhoň, R. Šámal, and A. Zámečník
  “Bolzano: Case Studies in LLM-Assisted Mathematical Research”
• P. Chmel, P. Hubáček, and D. Stejskal
  “Knowledge Soundness of Polynomial Commitments in the Algebraic Group Model Does Not Guarantee Extractability”
• J. Belohorec, P. Hubáček, and D. Stejskal
  “On Lifting AGM Security to AGM with Oblivious Sampling”

Publications

[1] P. Hubáček

“Black-box PWPP is not Turing-closed,” Information Processing Letters, 2026

[2] P. Hubáček, K. Mašková, and B. Richterová

“Practical adaptor signatures: Security and applications,” SCN 2026

[3] J. Belohorec, P. Hubáček, A. Kalsta, and K. Mašková

“CHOPIN: Optimal pairing-based multilinear polynomial commitments from bivariate KZG,” CRYPTO 2026

[4] C. Brzuska, P. Hubáček, and A. Kalsta

“Simple attacks against (extended) Fiat-Shamir,” PKC 2026

[5] P. Hubáček and M. Yeo

“On cryptographic cheap talk with smart contracts,” FC 2026

[6] C. Hoffmann, P. Hubáček, and S. Ivanova

“Practical batch proofs of exponentiation,” IACR Communications in Cryptology, 2025

[7] P. Hubáček, J. Václavek, and M. Yeo

“Foundations of fiat-denominated loans collateralized by cryptocurrencies,” OPODIS 2025

[8] J. Belohorec, P. Dvořák, C. Hoffmann, P. Hubáček, K. Mašková, and M. Pastyřík

“On extractability of the KZG family of polynomial commitment schemes,” CRYPTO 2025

[9] L. Folwarczný, M. Göös, P. Hubáček, G. Maystre, and W. Yuan

“One-way functions vs. TFNP: Simpler and improved,” ITCS 2024

[10] P. Hubáček, E. Khaniki, and N. Thapen

“TFNP intersections through the lens of feasible disjunction,” ITCS 2024

[11] E. Boyle, R. Cohen, D. Data, and P. Hubáček

“Must the communication graph of MPC protocols be an expander?” Journal of Cryptology, 2023

[12] R. Bourneuf, L. Folwarczný, P. Hubáček, A. Rosen, and N. I. Schwartzbach

“PPP-completeness and extremal combinatorics,” ITCS 2023

[13] C. Hoffmann, P. Hubáček, C. Kamath, and K. Pietrzak

“Certifying giant nonprimes,” PKC 2023

[14] C. Hoffmann, P. Hubáček, C. Kamath, and T. Krňák

“(Verifiable) delay functions from Lucas sequences,” TCC 2023

[15] P. Hubáček, L. Jančová, and V. Králová

“On the distributed discrete logarithm problem with preprocessing,” ITC 2022

[16] C. Hoffmann, P. Hubáček, C. Kamath, K. Klein, and K. Pietrzak

“Practical statistically-sound proofs of exponentiation in any group,” CRYPTO 2022

[17] I. Bentov, P. Hubáček, T. Moran, and A. Nadler

“Tortoise and hares consensus: The meshcash framework for incentive-compatible, scalable cryptocurrencies,” CSCML 2021

[18] P. Hubáček and J. Václavek

“On search complexity of discrete logarithm,” MFCS 2021

[19] P. Hubáček and E. Yogev

“Hardness of continuous local search: Query complexity and cryptographic lower bounds,” SIAM Journal on Computing, 2020

[20] P. Hubáček, C. Kamath, K. Král, and V. Slívová

“On average-case hardness in TFNP from one-way functions,” TCC 2020

[21] A. R. Choudhuri, P. Hubáček, C. Kamath, K. Pietrzak, A. Rosen, and G. N. Rothblum

“Finding a Nash equilibrium is no easier than breaking Fiat-Shamir,” STOC 2019

[22] P. Hubáček, M. Koucký, K. Král, and V. Slívová

“Stronger lower bounds for online ORAM,” TCC 2019

[23] E. Boyle, R. Cohen, D. Data, and P. Hubáček

“Must the communication graph of MPC protocols be an expander?” CRYPTO 2018

[24] P. Hubáček, A. Rosen, and M. Vald

“An efficiency-preserving transformation from honest-verifier statistical zero-knowledge to statistical zero-knowledge,” EUROCRYPT 2018

[25] B. Gärtner, T. D. Hansen, P. Hubáček, K. Král, H. Mosaad, and V. Slívová

“ARRIVAL: Next stop in CLS,” ICALP 2018

[26] P. Hubáček, M. Naor, and E. Yogev

“The journey from NP to TFNP hardness,” ITCS 2017

[27] P. Hubáček and E. Yogev

“Hardness of continuous local search: Query complexity and cryptographic lower bounds,” SODA 2017

[28] P. Hubáček, M. Naor, and J. R. Ullman

“When can limited randomness be used in repeated games?” Theory of Computing Systems, 2016

[29] S. Guo, P. Hubáček, A. Rosen, and M. Vald

“Rational sumchecks,” TCC 2016-a

[30] P. Hubáček and D. Wichs

“On the communication complexity of secure function evaluation with long output,” ITCS 2015

[31] P. Hubáček, M. Naor, and J. R. Ullman

“When can limited randomness be used in repeated games?” SAGT 2015

[32] S. Guo, P. Hubáček, A. Rosen, and M. Vald

“Rational arguments: Single round delegation with sublinear verification,” ITCS 2014

[33] P. Hubáček and S. Park

“Cryptographically blinded games: Leveraging players’ limitations for equilibria and profit,” ACM EC 2014

[34] P. Hubáček, J. B. Nielsen, and A. Rosen

“Limits on the power of cryptographic cheap talk,” CRYPTO 2013