Privons

Privons are a hypothetical class of information carriers proposed within privacy-preserving quantum information theory. They are conceived as quantum states that can participate in data-processing tasks while ensuring that information about individual inputs cannot be retrieved by external observers. In proposed models, privons enable aggregation and analysis of private data without exposing the underlying records.

The name privon combines privacy with the -on suffix used for subatomic particles, echoing particle-like behavior while signaling their role as privacy-preserving carriers.

In theoretical treatments, privons are often modeled as non-measurable or weakly observable excitations whose observable effects appear only in aggregated results. They may exhibit no-signalling constraints and be subject to no-cloning principles, with their states requiring joint measurement or specific protocols to extract useful statistics. Privons are not tied to a single physical medium and appear in various abstract frameworks, including quantum secret sharing and privacy-preserving quantum computation.

Proposed applications include privacy-preserving data analytics, secure multi-party computation, and controlled data release where only aggregate metrics are revealed. For example, a collection of parties could use privon-based encoding to compute an average without permitting reconstruction of individual records.

Privons remain speculative and controversial. Critics point to a lack of experimental demonstrations and questions about physical realizability, resource costs, and the robustness of privacy guarantees under realistic noise and attack models.

Related topics include quantum privacy, differential privacy, secure multi-party computation, homomorphic encryption, and quantum secure computation. There are no established standard definitions or widely accepted models for privons as of now.