The concept of information plays a striking role to describe the physical systems , these days . In practical view , the presence of physical nature depends on the concept of information . In this sight , information is a comprehensible concept which depends on recognition of living creature . Firstly , we investigate the entrance of information in physics then , by considering the thought experiment of Maxwell and Szilard , we answer this question whether or not the interference of intelligent being in a thermodynamic system will violate the second law of thermodynamics . The efforts to find a way to enter the information concept into physics world caused a connection between information and thermodynamics entropy . Existing the relation between information and entropy , and the conceivable ways to analyzing this connection is one of the most popular subjects to investigate . The connection can be studied in different aspects . In this inquiry , we tried to analyzing this connection by investigating the Maxwell’s thought experiment . He showed the statistical nature of second law of thermodynamics by imagining a creature called Demon . Since the existence of the creature could violate the second law of thermodynamics , many scientists tried to defeat the creature to save the second law of thermodynamics . The efforts lead to information entropy . In the second part of this research the primary views of Szilard and Maxwell about Demon is considered . Quantum information in comparison to classical theories is more advantageous since it applies the quantum mechanical features like entanglement which is one of the basic concepts of quantum mechanics . In the third part of this research the increase of information entropy and performed work in Szilard engine is investigated by entering entanglement . Finally , by entangling two regions in de Sitter space which is the most symmetric space , the entanglement entropy of a space is reached .