Quantum Cash

All consensus networks today are expensive, whether stake-based or hash-based. In Bitcoin land, concern has steadily grown that plunging issuance and low fees will create weak security, hashrate consolidation, and new attacks. In Ethereum land, concerns over paying a massive validator set have led to the tailspin of the so-called ‘ultrasound money thesis.’

One idea we love - and that stays true to the founding principle of Bitcoin - is quantum cash. Under this design, heavy consensus algorithms would be replaced (or augmented) with some form of a one shot signature. Instead of byzantine-proof incentives securing a network, physics which dictate one signature per one message would mitigate the ‘double-spend’ problem. 

There remain open issues around this design. Lost keys, tracking the total UTXO set, and stateful applications are a few critical ones. But the idea also has a lot of merit. Designs like lightning or zkcoins - which do payments out of band - could benefit from one-shot signatures, spiking total adoption, while Bitcoin’s proof-of-work could continue to operate under the hood. 

These advancements in encryption (and possibly throughput) will happen as miners face dwindling blockspace demand, causing many to close shop or take an exodus to more lucrative models of computation. Against the backdrop of lower fees and alternative revenues beyond mining, we think the oppurtunities to change Bitcoin with quantum are for the better.

Thanks to Bolton Bailey for feedback on this post.