[Florin_Andrei]

If you've tried recently to sync up a self-hosted ETH wallet app, you've probably noticed what an incredibly long time it takes to get the whole blockchain. Meanwhile the HDD is thrashing around like crazy; if you're not using an SSD then forget it. Wallet apps like Parity are a little more forgiving (probably smarter in how they handle the blockchain), but still, it's dozens of gigabytes already.

To me, the single, shared, universal blockchain idea seems more like a proof of concept. It's also pretty hard to ask every node in the network to see every possible transaction. I am virtually certain that whatever ends up taking over the world will not operate that way. Things just don't scale like that.

[ripply]

For anyone not familiar with some of the proposed scaling features for Ethereum, quadratic sharding could alleviate this problem by having hundreds of Ethereum universes that can talk to each other and commit their root merkle hash to the main chain

[Florin_Andrei]

Sounds like a good idea.

How are transactions routed from one "universe" to another? Let's say I'm on universe A, you're on universe B, and I want to send you a few bucks.