Quote from: achow101 on October 19, 2016, 11:24:04 PM

Quote from: RealBitcoin on October 19, 2016, 11:16:53 PM

This may sound silly or even genius, and I am not a big expert or cryptographer, but as I look at it, the public->private key system is 1 directional, so why do we need to use ECDSA when we could just use a SHA-256 instead or something like that. Lemme explain my theory:

Private key generated with RNG, then hashed with SHA256, the SHA256 hash , this would be the pubkey, and a Base58encoded checksumed version would be the bitcoin address
Bitcoin address and bitcoin private key included in blockchain at spending, so miners can verify the owner without the need for asymmetric cryptography, the private key would be revealed when you send money to a new address, so this way addresses will be forcibly reused, and would no longer serve as "accounts" but only as a receipt of transaction
The change would be sent back to the owner's change address, fee sent to miners, and the sum sent to the destination address
Mining protocol not affected
A lot of unnecessary work would be eliminated for both nodes and miners
More efficient cryptocurrency model
When you would sign a message with the address, it would automatically send the money from that address to a new address of yours, so that a message signing would still prove that you own that address, but the money need to be sent to a change address to ensure that the verifier doesnt stea it
Ultra secure, quantum secure, since we would no longer be constrained by a 128 bit private key, but by even a 1000 bit key by using numbers, letters, special characters to generate the private key, it would be way more secure

What do you think of my idea? Did Satoshi miss this thought?

You're wrong.

ECDSA is a signing algorithm that has specific requirements (all signing algos have specific requirements). It needs a public key derived from the public key in a specific way using a specific elliptic curve. The signature verification algorithm requires that specifically derived public key.

Your idea of publishing the private key when you send is also a bad idea. This is because the private key gives anyone who holds it permission to spend the UTXOs associated with the address. Once the private key is revealed after the Bitcoin is spent, while the transaction is unconfirmed, someone can retrieve that key and create a double spend and send the Bitcoin to himself instead of the intended recipient. A malicious miner could do this as well and ensure that he gets the Bitcoin because he is the one to include his double spend into a block.

What if the private key is sent after 6 confirmations? So the public key is indexed in the blockchain , and after 6 blocks the private key is sent and then the transaction would be finalized.

So that no node & miner could steal / double spend the coins, gets indexed to the blockchain, and then the private key is revealed, finalizing the transaction and confirming the spending.