LASIGE Talks are fortnightly/monthly events to publicise recently distinguished publications or ongoing cutting-edge work by researchers from the research centre, consolidating the scientific culture of the LASIGE community.

Speakers: Joel Samper (LASIGE) and Andreia Mordido (LASIGE/FCUL)
Date: October 1, 2025, Wednesday
Where: C6.3.27

Program:
12:00 Talk by Joel Samper
12:30 Talk by Andreia Mordido
12:55 Group Lunch

Talk1: How Can Technology Contribute to a Safer Sexting?
Speaker: Joel Samper
More and more people take advantage of mobile apps to strike up relationships and casual contacts. This sometimes results in the sharing of self-generated nudes. While this opens a way for sexual exploration, it also raises concerns. We review existing technology-assisted permissive approaches that provide security, privacy or accountability benefits when sharing nudes online. To do so, we performed a systematic literature review, and we identified real-world solutions by surveying app features. We systematize knowledge by defining a sexting threat model, deriving a taxonomy of the approaches, discussing some of their shortcomings, organizing privacy-related concepts, and providing take-aways with directions for future research and development.
Paper: https://eprint.iacr.org/2025/597

Talk2: Parametric Subtyping
Speaker: Andreia Mordido
In this talk, we will understand the concept of structural subtyping and see why subtyping is challenging when combined with recursion and polymorphism. We will introduce the notion of parametric subtyping and present an algorithm for deciding parametric subtyping of polymorphic types.
Paper: https://dl.acm.org/doi/10.1145/3632932