String theory tackles strange metals : Nature News: The hope is that tricks from string theory can now be used to make progress on improving the FFL model. One of its problematic aspects is the prediction of a state of matter that still has some level of order (non-zero entropy) at absolute zero (0 Kelvin). This violates the third law of thermodynamics, which says that, for FFLs, entropy should tend to zero as the system is cooled to absolute zero. Sachdev says he always considered this a shortcoming of his theory, but other physicists took the view that it might instead be saying something profound about real materials. "We never knew whether it was a bug or a feature," says Polchinski.
In his latest work, Sachdev shows that the string theory version of the FFL model also violates the third law of thermodynamics at absolute zero. The emergence of the same problem in a totally different mathematical framework suggests it is pointing to something in the real world, Polchinski says. Sachdev says more work will be needed to establish that for certain.