Web3 is centralized

Technically the part the preserves double spending is Ring CT however by and large I see it lumped under Ring sigs when discussed.

Here's a link to the Ring CT papers. The original explains the base system, 2.0 formalises the security of the system, and 3.0 describes how the original protocols had issues and how they were improved.

Original Ring CT Paper: https://eprint.iacr.org/2015/1098

Ring CT 2.0: https://eprint.iacr.org/2017/921

Ring CT 3.0: https://eprint.iacr.org/2019/508

Personally I find the Ring CT 3.0 paper to be the most enlightening of these. For a simpler/shorter explanation however, Moneropedia has some videos that are helpful in this.

https://www.getmonero.org/resources/moneropedia/ringsignatur...

https://www.getmonero.org/resources/moneropedia/ringCT.html

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The key details are these.

Monero uses a UTxO (unspent transaction outputs) accounting model. There are a number of networks that use this model, namely Bitcoin. The UTxO model doesn't strictly have a concept of accounts but rather keys and UTxO. You can think of UTxO as as atomic chunks of data/value. These UTxO are created once and used once. If you want to spend money, your inputs are UTxO, the outputs are UTxO, and the balances of all of these inputs and outputs must sum up to a net 0. Now UTxO can only be spent if a valid cryptographic signature can be produced. If your private keys can produce that signature, the value held in that UTxO can be spent by you.

This gives us our three key points. All UTxO consumed or spent in a Tx must collectively sum up to zero, UTxO can only be spent if the proof object/cryptographic signature produced is valid, and UTxO can only be spent if they haven't yet been spent.

First Ring CT has each sender derive a one time private key from their private key and a one time public key derived from the recipient's public key. These keys are used to produce a set of encrypted "coins" which essentially hold the value of the UTxOs being spent and then created. This allows the sender and recipient to know the contents of the actual meaningful transaction. Then a cryptographic proof verifies that out of all the public keys in the Tx, all the keys can spend their selection of coins included in the Tx and only one of them is the real set of coins. From there the balance is verified by doing that some clever math where the sum of the encrypted outputs is divided by the sum of the encrypted inputs must equal some constant determined by the encryption key. This is a bit of a simplification but it works out such that it is equivalent to "ins - outs = 0" in a traditional UTxO system.

The key/signature verification mentioned previously has a nifty property where the produced "key images" serve as what are effectively "hashes" of the UTxO. This means that if any key image has previously been used in a transaction, it effectively guarantees that the corresponding UTxO has already been spent. Going back and checking this is somewhat more expensive than on a traditional network however optimisations (like using a bloom filter) allow for this check to run significantly faster.

That's how Monero upholds those 3 properties that are required for consistency in a UTxO based network without leaking information about the sender, recipient, or balances. In short it's using one time PKI derivations to break information symmetry and then from there structuring the encrypted data so that you can use some clever arithmetic and signature checks to verify correctness.

Apologies if my explanation isn't terribly clear or perfectly accurate. It's my reasonably solid understanding of the system. I'm not a formally trained cryptographer or mathematician so my choice of words or explanations may be somewhat inaccurate however they give a reasonable coverage of how the system works. If you want to dive more into the meat of it, I'd seriously recommend the Ring CT 3.0 paper as it's really well put together once you can get through the terse notation and dense amount of information.

> So you're talking about a year and a half window since it was first conceived to have such discussion, less than 12% of the entire time bitcoin has been in existence.

It doesn’t matter. My point is that was the only time the discussion was actually dominated by people interested in the technology. It’s a reference to a point in time and the tone of discussion around then. I was in security academia at the time and discussions were level-headed about bitcoin, hash cash, and other digital currencies.

> there was probably some talk about it eventually being exchanged for USD right from the start.

There was, but that wasn’t the technology talk that dominated the discussion. There is a reason it sat around for so long until the famous pizza purchase. It was about the technology at the start.

> Yeah that's not true. On HN that may be more or less true (although I care about the tech and I'm on HN), but there's plenty of people that care about the tech and are discussing it in other channels.

To a rough approximation, it’s about 0% of the people interested in crypto though. There are maybe a few thousand actual active crypto developers (and that’s being generous). The number of people who buy crypto to invest/gamble is now in the millions. The conversations are always going to be dominated by topics surrounding the latter because it’s so controversial.

The only way to get to technical discussions is to weed out the people who don’t like it, so you basically have to stay off any general technology forums (HN, chunks of Reddit, etc).

> And intelligently, too, not just "I like the web3 makes me money go fast moon please." like it seems everyone on HN assumes these people think.

That’s a strawman of crypto detractors. It doesn’t help you to model opposing arguments that way.

> There are people legitimately trying to do new and interesting (to me anyway) things with the space, and donating their time and energy and cash to try to build it and make it happen.

Sure, but pretending to invent an entire new generation of the internet (“web3”) is overly grandiose and the better discussions happen around specific technologies.

This is a technology forum populated by developers, they shouldn’t be the out of touch speculators and critics of speculators

Nope, you misunderstand what I am saying. Every transaction loses money and this is built in. That's not true for cash.