Ray Dalio owns Bitcoin. He is still nervous about quantum computing and its adoption by central banks.

Bitcoin was built for an apocalyptic world, but it still has disadvantages as a store of value compared to gold, according to Ray Dalio, founder of Bridgewater.

Anyone with an internet connection can secure digital assets themselves. But those people are still dependent on others, including a global network of machines to process transactions, the billionaire investor spotted during an interview on thursday with CNBC.

This year, the price of the precious metal has soared to record highs on fears of currency depreciation, which Dalio alluded to in July when encourage investors to hedge against macroeconomic risks surrounding rising government debt, in the US and abroad.

At the time, Dalio expressed a preference for gold, and on Thursday he reiterated concerns about the native cryptocurrency to the extent it can stand the test of time or be used by central banks to facilitate international trade and stabilize economies.

“I think the problem is with Bitcoin [that] it will not become a reserve currency for major countries because it can be tracked, and it could conceivably be monitored with quantum computing, hacked, etc.,” he said.

Last week, the Czech National Bank revealed his first investment in crypto, with $100 million spread across Bitcoin, stablecoins and tokenized bank deposits. Officials said the “test portfolio” will help the central bank better understand how to handle digital assets.

While it may take years before quantum computers are strong enough to crack Bitcoin’s encryption, there are growing calls for a solution precautionary measures within the industry, such as tech titans such as Google and IBM tout breakthroughs.

Because transactions are recorded on a public ledger and visible to all, tracking someone’s Bitcoin is quite easy once the identity is linked to a digital wallet, pending the use of coin mixersthat obscure the source and destination of flows by pooling funds.

Dalio said a “small percentage” of his portfolio has long been Bitcoin, but he estimated it to be 1% of his total assets. In July, Dalio suggested that investors allocate at least 15% of their holdings to Bitcoin and the precious metal.

Gold is advantageous as a store of value because it can be physically stored without having to rely on someone to deliver, Dalio said. Still, he considers Bitcoin and gold hard currencies because their value cannot be reduced by a government through money printing.

Dalio’s concerns about relegation are linked to rising US debt, but he said several countries are also facing rising deficits, including Britain and France, which could lead to what he wants. described months ago as a “debt-induced heart attack.”