If you believe Bitcoin has the potential to replace traditional global financial systems, a new economic analysis is here to rain on your parade.

The discussion of digital money thus far has been dominated by libertarians and computer geeks, but the massive popularity of crypto-tokens has gotten the attention of academics such as the University of Chicago’s Eric Budish. In a new paper, Budish examines Bitcoin’s incentive system and concludes that there are “intrinsic economic limits to how economically important it can become.”

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Some “Bitcoin maximalists”—those who hope the digital currency will squeeze out all competitors—say that it’s a lot like gold: it works as a store of value, even if it’s not very efficient as a true currency. But if Bitcoin got anywhere close to gold’s value, Budish argues, people would attack its network for profit.

Before we dive into the argument, a little context: Bitcoin’s market capitalization over the last year or so has oscillated between $100 billion and $200 billion. Gold stock is worth about $7.5 trilllion. So, yeah, in those terms, Bitcoin is nowhere close to being “economically important.”

And according to Budish, it never will be. That’s because if it ever gets too large, the genius of Bitcoin’s design would be its undoing.

Bitcoin’s security arises from a competition between members of the blockchain network called “miners.” Each miner is in pursuit of chances to add new transactions to the blockchain and earn bitcoins in return. Miners use large amounts of computing power in a race to solve a complicated math problem. An attacker couldn’t defeat this system unless it coordinated enough computing power to overwhelm the network and manipulate the record of transactions in such a way that it could spend the same bitcoins repeatedly. A strike of that sort, called a “majority attack,” is Bitcoin’s biggest threat, but for now, mining coins is more profitable than trying to overthrow the network, so the network stays safe. (See “How secure is a blockchain really?”)