P3: zero mutual information (four-term flagship)
Read as: Once challenge C is fixed, observing transcript O gives no mutual information about secret index J, private morphism φ, selector path σ, or message M.
Arguments
- J
- : active secret index in a multi-secret family
- \varphi
- : private synonym morphism; stays off-channel
- \sigma
- : private selector path through the public scaffold
- M
- : message or content variable protected by the channel claim
- O
- : observable transcript or recorded ceremony events
- C
- : public challenge that defines the legal selector paths
Operators
- I
- : conditional mutual information
- \mid
- : conditioned on the challenge
- = 0
- : observer-effective leakage is zero under P1–P3
Significance: This is the New Dimensions flagship: structural absence of secret-relevant information in the transcript, not a hardness calendar.
Computational contrast: P3 is not a hardness assumption; it says the transcript lacks secret-relevant information rather than hiding recoverable information behind work factor.
References:Channel ZeroInformation-theoretic authorizationNew Dimensions PDF
