Edwards cancellation theorem

We emphasize that the use of g in these equations may be justified only if /—a, because of the Edwards cancellation theorem (Section 6). We should expect a metal-insulator transition to occur for some value of in the neighbourhood of For several liquid systems there is experimental evidence that the interference term in (52) is absent. Thus for liquid TeTl alloys, with variation of composition and temperature, for a less than the Ioffe-Regel value e2/3hai the conductivity is proportional to the square of the Pauli paramagnetic susceptibility and then to 2. These results are due to Cutler (1977). Warren (1970a, b, 1972a, b) examined... 

The assumption that a is proportional to the square of the density of states is normally deduced only in the regime weak localization. For the singularity predicted by Altshuler and Aronov, any correction to dE/dk will be zero if averaged over a range kBTabout EF. We consider then that if a>%,... 

Since the mean free path A is already quite short in the dense metal, the conclusion seems unavoidable that the loffe-Regel limit of the NFE regime is reached around 11 g cm so that A a and, moreover, that the Edwards cancellation theorem begins to fail. Thereafter, with further reduction of the density to about 9 g cm , the conductivity drops by another order of magnitude and the Hall coefficient increases sharply to about three times the free electron value. 

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