We construct entanglement witnesses using fundamental quantum operators of spin models which contain two-particle interactions and have a certain symmetry. By choosing the Hamiltonian as such an operator, our method can be used for detecting entanglement by energy measurement. We apply this method to the Heisenberg model in a cubic lattice with a magnetic field, the XY model and other familiar ...

A class of graphs ℱ ${\rm{ {\mathcal F} }}$ admits the Erdős–Pósa property if for any graph G $G$ , either has k $k$ vertex-disjoint “copies” in or there is a set S ⊆ V ( ) $S\subseteq V(G)$ f $f(k)$ vertices that intersects all copies . For ${\mathscr{G}}$ it natural to ask whether family obstructions property. In this paper, we prove interval graphs—namely, chordless cycles and asteroidal wit...

If the witnesses of 19th-century civil marriages have been subject several researches, especially to distinguishing related and non-related witnesses, less attention has paid precise choice family members or witnesses. Even parents brides grooms, their presence absence at child's marriage, consequences on call friends The idea this article is provide new information about people who attend wedd...

Many witnesses to violent crimes are alcohol intoxicated, but research is lacking regarding how alcohol affects their perception of aggression and guilt. This study investigated to what extent alcohol intoxicated eyewitnesses differed from sober witnesses regarding how aggressive and guilty they perceived the involved parts in an intimate partner violence (IPV) situation. Eighty-seven healthy m...

In a celebrated paper, Valiant and Vazirani [29] raised the question of whether the difficulty of NP-complete problems was due to the wide variation of the number of witnesses of their instances. They gave a strong negative answer by showing that distinguishing between instances having zero or one witnesses is as hard as recognizing NP, under randomized reductions. We consider the same question...