Small stars that formed by gravitational collapse, the theory goes, will have a similar make-up to their parent stars, since they both emerged from the same cloud.

ECONOMIST: Twinkle, twinkle, giant planet

Like the hard landing theory, Way is not subscribing to a housing collapse either.

FORBES: At Touchstone, Right Call On China

Lerach's Enron case worries other lawyers, who say his theory could entangle just about anybody involved in a business collapse.

FORBES: Magazine Article

Another theory suggests that material surrounding a young star can undergo gravitational collapse under its own mass.

WSJ: Possible New Planet Spotted Under Formation

Moreover the financial institutions that in theory should have supplied that capital were the cause of the collapse.

FORBES: Adeo Ressi's Founder Institute Sprouts Start-ups Around The Globe

Theory suggests that a certain type of giant, short-lived star can experience catastrophic collapse when the nuclear reactions at its core can no longer support its mass.

BBC: Telescope spies cataclysmic blast

What about the theory that Japan is so rich a nation that it can buy its way out of a financial collapse?

FORBES: The Panic Spreads

One conspiracy theory is that hedge funds distorted CDS prices, which in turn spooked the stock market and caused a collapse in confidence.

ECONOMIST: Speculators