Having two candidates for a theory of everything is almost as upsetting to physicists as their inability to reconcile quantum mechanics and general relativity in the first place.

ECONOMIST: A new ��theory of everything�� is gaining ground

In particle physics, sound-bite explanations are much harder: wave-particle duality, quantum mechanics, general relativity and string theory make good mathematical sense, or so I am told, but they generally defy translation into English.

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Roger Penrose, for example, has long been on record as arguing that it is quantum mechanics, not general relativity, that needs to be modified in order to successfully develop a grand unified theory.

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In any case, general relativity directly contradicts quantum mechanics, the other great physical theory of the 20th century, so more and more precise tests need to be carried out to find out what cracks might exist in either theory.

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He rewrote the equations of general relativity to make them compatible with quantum mechanics.

ECONOMIST: A new ��theory of everything�� is gaining ground