Grunnleggende konsepter
Quantum one-way state generators (OWSGs) with O(n/log(n)) copies are equivalent to quantum commitments and to polytime-copy OWSGs. The weakest OWSGs from which quantum commitments can be obtained are those with O(n/log(n)) copies.
Sammendrag
The content discusses the relationship between quantum one-way state generators (OWSGs) and quantum commitments.
Key highlights:
- OWSGs are quantum analogues of classical one-way functions, where the output is a quantum state rather than a classical string.
- It is shown that O(n/log(n))-copy OWSGs are equivalent to polytime-copy OWSGs and to quantum commitments.
- This establishes that O(n/log(n))-copy OWSGs are the weakest OWSGs from which quantum commitments can be obtained.
- The proof follows a construction similar to the classical case of obtaining pseudorandom generators from one-way functions, but with crucial modifications to handle the quantum setting.
- The construction involves flattening the quantum state, using properties of Rényi entropies, and applying quantum extractors to amplify the statistical difference between the commitment states.
- The reverse direction, showing that quantum commitments imply polytime-copy OWSGs, is also established.
- These results connect quantum commitments to the fundamental primitive of OWSGs, and have implications for secure multi-party computation in the quantum setting.