  We propose to study equivalence relations between phenomena in high-energy
physics and the existence of standard cryptographic primitives, and show the
first example where such an equivalence holds. A small number of prior works
showed that high-energy phenomena can be explained by cryptographic hardness.
Examples include using the existence of one-way functions to explain the
hardness of decoding black-hole Hawking radiation (Harlow and Hayden 2013,
Aaronson 2016), and using pseudorandom quantum states to explain the hardness
of computing AdS/CFT dictionary (Bouland, Fefferman and Vazirani, 2020).
  In this work we show, for the former example of black-hole radiation
decoding, that it also implies the existence of secure quantum cryptography. In
fact, we show an existential equivalence between the hardness of black-hole
radiation decoding and a variety of cryptographic primitives, including
bit-commitment schemes and oblivious transfer protocols (using quantum
communication). This can be viewed (with proper disclaimers, as we discuss) as
providing a physical justification for the existence of secure cryptography. We
conjecture that such connections may be found in other high-energy physics
phenomena.
