Crypto news

Hashcash creator and one of the key architects of the crypto space, Adam Back, presented what he jokingly called the "E=mc² formula for Bitcoin." This is not a mathematical equation, but a conceptual string that gathered tens of thousands of views in a few hours and sparked heated discussion in the professional community.

This comparison to Einstein's equation is conceptual, not literal. Back wanted to show that one short string can encapsulate the essence of an entire system, much like the famous E=mc² describes the relationship between energy and matter. Let's break down what exactly he encoded in this entry and why the community received it with such enthusiasm.

The three pillars on which Bitcoin stands

To understand the "formula," you don't need to be a mathematician—just imagine the three pillars that support Bitcoin:

• Computational work (Proof-of-Work). Computers around the world solve a complex numerical problem through brute force to add a new record to the network. This is intentionally costly: it's impossible to falsify history retroactively because you would have to redo all the work.
• Chain of blocks (blockchain). Records in Bitcoin are not chaotic—each new block references the previous one, forming a single continuous chain. This makes it impossible to secretly rewrite history in the middle.
• Scheduled issuance (halving). New bitcoins appear as a reward to whoever adds the next block. The reward size is predetermined and halves every four years—this event is called the halving. Thus, the total number of coins grows according to a predictable schedule set from the very beginning.

The genius of Back's entry is that he packed these three pillars into a single line.

What is written in the "formula"

The entry itself looks like this:

c | { h_(i+1) = H(h_i, c, 50/2^h ₿) } < T

Each symbol here represents one of the pillars we discussed.

The letter H is a data "shredder," or hash function. It turns any set of information into a fixed-length string. h_i and h_(i+1) are the previous and next blocks; the fact that one references the other is the chain itself. The letter c denotes a new block template with a list of transactions.

The fraction 50/2^h ₿ is the issuance schedule: 50 bitcoins at the start, and each halving divides the reward in half. Finally, T is the difficulty target: the computation result must be less than it, otherwise the block won't be accepted. The entire line reads as a condition: "find such a block template that the result falls below the target."

An important caveat, which Back himself makes: the formula is conceptual, not literal. In real mining, the reward doesn't enter the computation directly, but through a special coinbase transaction that is folded together with the others into the block's overall "fingerprint." Back omitted these technical layers for the sake of elegance and brevity: the line conveys the logic, not the exact sequence of machine operations.

Where the roots come from

This formula has a backstory spanning a quarter of a century. Back in the late 1990s, Back invented Hashcash—a system to combat spam. The idea was to force the sender of an email to perform a small amount of computational work. For a single email, this is imperceptible, but for a million-piece spam campaign, it becomes too expensive.

It was precisely this technique—"prove you did work" (Proof-of-Work)—that later became the foundation of Bitcoin. But Hashcash had neither a chain of blocks nor rewards for work. The creator of Bitcoin under the pseudonym Satoshi Nakamoto took Back's idea and added the missing pieces: linked the records into a chain and added a coin issuance schedule. Therefore, the essence is often described with a simple scheme: work plus chain plus economics equals Bitcoin.

Community reaction and my view

Under the post, one user shared a detailed infographic that broke down the formula into parts and visually compared Hashcash to Bitcoin. Back publicly praised this analysis.

The episode is notable not for a new discovery, but for a successful attempt to condense Bitcoin's foundation into one memorable line—understandable to both an engineer and someone without a technical background.

Analyst's comment: This "formula" is not just a fun analogy. It demonstrates the elegance of Bitcoin's design, which has remained the benchmark for decentralized systems for 15 years. For me as an analyst, it is especially valuable that Back managed to pack three key mechanisms—consensus, immutability, and issuance—into a single line. This is the best proof that genius often lies in simplicity.