Dave Collum, professor of organic chemistry at Cornell University, was able to sidestep the financial crisis after he noticed a calamity brewing in subprime mortgages as early as 2002.

Today, he sees vast corporate excesses, massive debt loads, and extremely exuberant valuations as cause for concern.

Collum warns of a 50% stock crash that would bring valuations back to historical averages.

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Investor anxiety in today's marketplace is palpable.

Much of that nervous, jittery feeling can be attributed to the coronavirus as fears of a global pandemic weigh on market sentiment.

Still, outside of the virus vaccum, some think that stocks are long overdue for a downturn.

Dave Collum, professor of organic chemistry at Cornell University, aligns with that school of thought — and he thinks the Federal Reserve is to blame.

"I think they're idiots; I think they're delusional," he said on the "Jelly Donut Podcast," which focuses on investing. "I think the Fed's goal is to somehow deflate this whole mess, and somehow bridge asset prices right across the valley of death to get to the other side."

He continued: "I think we'll have a colossal disaster at some point."

This isn't the first time Collum's seen trouble brewing from a mile away. In 2002, he wrote a letter to Goldman Sachs warning of the nefarious activity taking place in subprime mortgage lending. Due to his foresight, Collum was able to sidestep the crisis — and according to him, compounded his returns at a rate of 13% from 2000 to 2009.

Collum's diagnosis of today's market is rather simple: Both stocks and bonds are in "monstrous" bubbles initiated by the Federal Reserve's lax policies.

"This bubble is the entire bubble," he said. "The Fed won't let it drop; that's moronic."

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Collum points to vast corporate excesses, swaths of borrowed cash used to fund stock buybacks, and extremely overstretched valuations to build upon his thinking.

What's more, he says that GDP has grown maybe 50% (he's skeptical over the official numbers) from the depths of the financial crisis. He contrasts that with how equity markets have more than quadrupled over that same time frame. He thinks this is a clear dislocation.

"They're supposed to track each other — among the many metrics — they're supposed to track each other. That's Buffett's favorite, right?" he said in reference to the US' stock market capitalization to GDP ratio. "Somethings out of whack."

In addition, Collum says that the idea that low interest rates are bullish for equities is a misnomer. He says that rates are low because the economy is weak, and therefore don't justify lofty stock market valuations.

Against that backdrop, Collum delivers a stark warning.

"My model is we're either going to have a very, very mean recession or I'm wrong," he said. "Regression to the mean is a 50% cut — and that'll destroy CalPERS, and that will destroy hedge funds (except the smart ones).

He concluded: "That'll destroy all the endowments. 50% is a monster."