Explains proof-of-work as the price of truth, not puzzle solving. Covers how it solves the double-spend problem, secures the entire chain, the thermodynamic arrow of time, the difficulty adjustment, and why a 51% attack is self-defeating.
Bitcoin secures its ledger by making lying expensive. This course explains proof of work not as solving puzzles, but as the price of truth, converting real energy into unforgeable costliness. I cover how proof of work solves the double-spend problem and secures the entire chain, why the blockchain is a kind of thermodynamic arrow of time, how the difficulty adjustment keeps blocks arriving roughly every 10 minutes, and why a 51% attack is economically self-defeating, security here is enforced by loss.
This is educational content, not financial advice.