Theoretical Methods For Strongly Correlated Electrons
|Title||Theoretical Methods For Strongly Correlated Electrons|
|Publication Type||Book Chapter|
|Year of Publication||2004|
|Authors||Allen S, Tremblay A-MS, Vilk YM|
|Editor||Sénéchal D, Tremblay A-MS, Bourbonnais C|
|Chapter||Conserving approximations vs. two-particle self-consistent approach|
The conserving approximation scheme to many-body problems was developed by Kadanoff and Baym using the functional-derivative approach. Another approach for the Hubbard model also satisfies conservation laws, but in addition it satisfies the Pauli principle and a number of sum rules. A concise formal derivation of that approach, using functional derivatives, is given in this conference paper to highlight formal analogies and differences with conserving approximations.