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Message-ID: <08201f2292587821e6d23f6cc201d95e6e5ad2cd.camel@timruffing.de>
From: Tim Ruffing <crypto@timruffing.de>
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Date: Sun, 08 Jul 2018 17:16:34 +0200
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Subject: Re: [bitcoin-dev] Multiparty signatures
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Hi Erik,

On Sun, 2018-07-08 at 10:19 -0400, Erik Aronesty via bitcoin-dev wrote:
> Consider changing the "e" term in the schnorr algorithm to hash of
> message (elligator style) to the power of r, rather than using
> concatenation.  

How do you compute s = x*e if e is an element of group G?
(Similar question: How do you verify if e is element of G?)

Are you aware of 
 http://cacr.uwaterloo.ca/techreports/2001/corr2001-13.ps ?
This is a threshold signature scheme for Schnorr signatures, so what
you want is possible already with Schnorr signatures.

Best,
Tim