4 papers
The NPA hierarchy does not always attain the commuting operator value
Marco Fanizza, Larissa Kroell, Arthur Mehta +4
We show that it is undecidable to determine whether the commuting operator value of a nonlocal game is strictly greater than 1/2. Specifically, there is a computable mapping from T…
Deciding Whether a C-Q Channel Preserves a Bit is QCMA-Complete
Kiera Hutton, Arthur Mehta, Andrej Vukovic
We prove that deciding whether a classical-quantum (C-Q) channel can exactly preserve a single classical bit is QCMA-complete. This "bit-preservation" problem is a special case of…
A classical proof of quantum knowledge for multi-prover interactive proof systems
Anne Broadbent, Alex B. Grilo, Nagisa Hara +1
In a proof of knowledge (PoK), a verifier becomes convinced that a prover possesses privileged information. In combination with zero-knowledge proof systems, PoKs play an important…
Unclonable Functional Encryption
Arthur Mehta, Anne Müller
In a functional encryption (FE) scheme, a user that holds a ciphertext and a function key can learn the result of applying the function to the plaintext message. Security requires…