Truncated Conformal Space Approach (TCSA) is a highly efficient method to compute spectra, operator matrix elements and time evolution in quantum field theories defined as relevant perturbations of 1+1-dimensional conformal theories. However, similarly other exact diagonalisation methods, TCSA ridden with the “curse dimensionality”: dimension Hilbert space increases exponentially (square root t...

The BFT approach is used to formulate the electronic states in graphene through a non-commutative space in the presence of a constant magnetic field B for the first time. In this regard, we introduce a second class of constrained system, which is not gauge symmetric but by applying BFT method and extending phase space, the second class constraints  converts  to the first class constraints so th...

Researchers have identified and defined β- approach normed space if some conditions are satisfied. In this work, we show that every is a space.However, the converse not necessarily true by giving an example. addition, define β – Banach space, examples given. We also solve problems. discuss finite β-dimensional app-normed β-complete consequent app- space. explain metric but give propositions. If...

In this paper two external schema generation algorithms are presented. These algorithms are defined in the framework of the new external schema definition methodology for OODBs put forward in (Samos, 1995); they generate an external schema from a set of classes selected from those existing in an external schema definition repository. Their main characteristic is that they avoid the generation o...