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Date: Sun, 21 Dec 2014 18:10:47 +0000
Message-ID: <CALqxMTFK_sxdFjVi0qAC0JMdXa=tVBBNp0VrveRUfwa3b1UYhw@mail.gmail.com>
From: Adam Back <adam@cypherspace.org>
To: Peter Todd <pete@petertodd.org>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: [Bitcoin-development] one-show signatures (Re: The relationship
 between Proof-of-Publication and Anti-Replay Oracles)
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Yes you could for example define a new rule that two signatures
(double-spend) authorises something - eg miners to take funds. (And
this would work with existing ECDSA addresses & unrestricted R-value
choices).

I wasnt really making a point other than an aside that it maybe is
sort-of possible to do with math what you said was not possible where
you said "This [preventing signing more than one message] is
impossible to implement with math alone".

Adam

On 21 December 2014 at 15:29, Peter Todd <pete@petertodd.org>
> There's no need to get into the specifics of crypto math so early; you
> can just as easily and only slightly less efficiently obtain the same
> result with a few extensions to the Bitcoin scripting system to verify
> ECDSA signatures directly.