Non-Malleable Time-Lock Puzzles and Applications (via Zoom)

Abstract: Time-lock puzzles are a mechanism for sending messages "to the future", by allowing a sender to quickly generate a puzzle with an underlying message that remains hidden until a receiver spends a moderately large amount of time solving it. In this talk, Naomi will discuss her recent work which introduces and constructs a variant of a time-lock puzzle which is non-malleable, which roughly guarantees that it is impossible to "maul" a puzzle into one for a related message without solving it.

Naomi will demonstrate how non-malleable time-lock puzzles can be used to achieve fair multiparty coin-flipping protocols. Specifically, this work gives the first non-interactive protocol in the plain model without setup, as well as a practically-efficient protocol in the (auxiliary-input) random oracle model. She will also discuss the notion of functional non-malleability, which we introduce as a key concept toward proving the security of our protocols, and may be of independent interest.

Based on joint work with Cody Freitag, Ilan Komargodski, and Rafael Pass.

Bio: Naomi Sirkin is a Ph.D. candidate in Computer Science at Cornell University, advised by Professor Rafael Pass. Her research interests are broadly in the field of Cryptography. She is a recipient of the JP Morgan AI Research Ph.D. Fellowship. Prior to graduate school, she received a B.S. in Computer Science from Johns Hopkins University.