Tamer Mour's Homepage
Last updated: October 25, 2024

Academic Profile
I am a postdoctoral researcher in computer science at CIFRA lab at Bocconi University, hosted by Prof. Alon Rosen.

I recently obtained my PhD from the Weizmann Institute of Science under the supervision of Prof. Zvika Brakreski. Before that, I received my Matser's degree in Technion, under the supervision of Prof. Eyal Kushilevitz.

Despite cryptography being my main focus in my graduate studies, I am generally interested in modelling and solving problems that arise in societal interactions, via theoretical computer science and math.

cv.pdf | e-mail: [firstname].[lastname]@unibocconi.it

Research Work
Reverse chronological order. See also my dblp or Google Scholar page.
A New World in The Depths of Microcrypt: Separating OWSG and Quantum Money from QEFID
with Amit Behara, Giulio Malavolta, Tomoyuki Morimae and Takashi Yamakawa

While we know that OWFs are the minimal assumption ... underlying classical cryptography, the search for a minimal assumption in quantum cryptography, i.e. in Microcrypt, has been troubling researchers in the field. Although many candidates have been proposed, a definite answer is still out of reach, and the relation between the various contenders is unclear. In this work, we shed light on the relation between two of the more prominent candidates: OWSGs and QEFIDs, suggesting the existence of further heirarchy inside Microcrypt. In particular, we show that average-case problems, with quantum instance and classical solution, become easier in some sense when the solution is efficiently verifiable. more

Paper | Talk
Locally Testable Tree Codes
with Alon Rosen and Ron Rothblum, to appear in SODA'25

Suppose we wish to encode a huge amount of data that is created across multiple generations. Each generation creates new information and we would like to encode it in an online manner into a... repository. We want the encoding to be such that we can still decode and retrieve the information even if few errors happened along the way. Further, we want to be able to test that the stored data is properly encoded by reading only a few locations in the (potentially huge) repository. In this work, we build the first locally testable tree codes, which offer a solution to such a scenario. more

Paper
The Black-Box Complexity of Correlation Intractability
with Nico Döttling, appeared in ITCS'24

Correlation intractable hash functions are functions where it is hard to find an input-output pair satisfying some desired correlation. Such functions are a central tool in communication-efficient... cryptographic protocols. In this work, we investigate the complexity of building correlation intractable hash functions from basic cryptographic building blocks: one-way functions, i.e. functions that are hard to invert, or collision-resistant hash functions, i.e. functions under which it is hard to find two colliding inputs. more

Paper | Talk
Non-Interactive Zero Knowledge from LPN and Trapdoor Hash
with Zvika Brakerski and Venkata Koppula, appeared in CRYPTO'20

Imagine you want to prove a computational statement over some secret (e.g. a password) without leaking any information about the secret. You also want to do so by sending a one-shot proof... , without any interaction with a verifier. Non-interactive zero knowledge (NIZK) proofs are the tool to accomplish this cryptographic task. In this work, we lower the bar for the cryptographic structure needed to build NIZKs. Specifically, we build such proofs where security is based on the LPN and DDH assumptions, which encompass much weaker structure than the assumptions known to imply NIZKs before, e.g. LWE, QR or Factoring. more

Paper | Short Talk | Long Talk
Trapdoor Hash Functions and Their Applications
with Nico Döttling, Sanjam Garg, Yuval Ishai, Giulio Malavolta and Rafail Ostrovsky, appearead in CRYPTO'19

One of the main goals in the design of secure computation protocols is to reduce the communication cost needed for privacy. In... this work, we introduce a new cryptographic building block, which we call trapdoor hash functions, that allows to build communication-efficient protocols for prominent cryptographic functionalities, e.g. oblivious transfer and private information retreival. more

Paper | Talk
New Efficient Constructions for Distributed Oblivious RAM
with Eyal Kushilevitz, appeared in PKC'19

Consider the problem of privately outsourcing a database to remote server(s). While encryption can be used to hide the data itself, one must use oblivious RAM to hide the access pattern to the data. In this... work, we make progress in constructing efficient oblivious RAM protocols where the database is stored in two or more servers. more

Paper
Other Projects
Tatreez
with Sama Haddad and Shahd Issa

Tatreez is a prominent form of traditional Palestinian embroidery. In this project, we look into the beautiful geometry in tatreez and build an algorithm that generates original tatreez peices. At every run... of the algorithm, a fresh random peice is produced, where different shapes and new patterns appear. The algorithm thus gives birth to a never-ending collection of unique tatreez peices; some traditional-looking, some rather quirky, but all unpredictable! more

Try it yourself