[Cryptography] Proof of Work is the worst way to do a BlockChain

[jamesd at echeque.com]

On 24/02/2018 12:02, Ray Dillinger wrote:
> You can check the validity of any proposed transaction by downloading a
> subset of the block chain rather than the whole thing.  You will need
> something on the order of the fourth root of all blocks, per block that
> a txIn being used in the transaction came from, to make sure that it
> hasn't been spent since it was created.  And if the tx that created it
> had multiple inputs, you will need something on the order of the fourth
> root of all blocks *younger* than the block the tx is in, to find each
> of those.  Etc.  Until you reach a known block at which a known txOut
> set existed. (But building that known block/known txout set still
> requires you to traverse the whole block chain up to that point. )


Suppose a limited set of wealthy and powerful people have the necessary 
resources to check the whole blockchain - and several such people, 
subject to different nuclear umbrellas, with server farms in separate 
nuclear umbrellas, have done so.  You might decide to trust them for all 
transactions up a month or so ago, and only check more recent transactions.


OK. What is your design?  (I have a proof of stake mechanism cooking, 
which solves the miner problem)