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According to modal interpretations of quantum mechanics, a state possesses definite values even if it is not an eigenstate. On the other hand, Kochen-Specker theorem holds that all possible possessed values by a system can not be definite. Consequently, modal interpretations to block this theorem, take new metaphysics of properties. In this dissertation, I will show that dispositionalism is that metaphysics. According to dispositionalism, causal powers of a property are constituents of the property. As regards this outline, the thesis would be divided into 5 chapters. In chapter one, presuppositions of later arguments are clarified. Chapter two is related to algebra of properties and finally... 

The relationship between quantum theory and thermodynamics has gained so much attention in recent years. Thermodynamics is indeed a phenomenological science and its theoretical foundations are not clear as well. In the nineteenth century, Boltzmann tried to establish a connection between concepts of thermodynamics and classical mechanics (as a consistent theoretical domain). With development of quantum mechanics in twentieth century, the possibility of analyzing and formulating of the multi-particle systems based on quantum formalism increased. Quantum approach to thermodynamic phenomena has been studied in various ways. Here basic questions are, e.g. how to define Thermodynamic entities... 

In this thesis we are going to explore a new formalism in micro domain which describes quantum phenomena in a realistic casual fashion by introducing an unified concept of matter, energy, and Information. In this theory, a micro-entity, e.g. an electron, is a combination of a particle and its associated field integrated to a new entity called particle-field. The dynamics of such system will be analyzed. Then, some quantum examples which have controversial aspects will be discussed within the new theory. In a generalized form of formalism, the non-linear Schrödinger Equation is introduced, which enables us to predict some experimental data for common Quantum Mechanical stationary systems.... 

Bohm-de Broglie theory is an alternative for standard quantum mechanics for explaining the bizarreness of micro-phenomena. This theory is casual and deterministic,but endows with nonlocal and contextual characters. Up to now,two different approaches presented: One is known as Bohm-Hiley (BH) formalism and the other is Dürr-Goldstein-Zanghí (DGZ) representation. In BH formalism, quantum potential has a significant role, according to witch peculiar phenomena such as quantum tunneling, two-slit interference and chemical bond are explained. Active information is also another important rotion introduced by quantum potential. In DGZ approach, however, the foundation of Bohm theory is based on... 

Bohm theory is an alternative for standard quantum mechanics which, provides a deterministic description for physical microsystems. In this theory every physical system, describes as a quantum particle which guided by a correspondiente wave. In stationary states every wave-particle, depends on its initial conditions, is at rest in different points. As an example in hydrogen atom, stationary states means electron, with constant radius and polar angle, has a circular motion in planes which is parallel with xy plane. In this thesis the stationary trajectories of hydrogen atom has been reconsidered and new trajectories are sketched. Also by extension the discussion to the macrosystems, we study... 

Regarding the notable progress in communication and competition theories as well as natural sciences, the study of the concepts of information has displayed more attention in recent years.Information, entropy and energy are interrelated concepts. In one hand one can infer that entropy is a quantitation measure of information and on the other hand systems which carry information can accumulated energy.Here, we are going to survey the qualitation as well as quantitation aspects of information with concentration on the behavior of chemical agents as information processors  

In order to study the phenomenon of consciousness, many physicists have presented their views. In this thesis, the phenomenon of consciousness is analyzed from Henrry Stapp and Penrose-Hameroffs’ viewpoints. Assuming the subjective reduction of state vector, Stapp considers conscious mind as prerequisite for the reduction of wave function. In his view, consciousness is a selection agent which has a top-level control over brain stimulations,and every conscious experience is the feeling of the top-level event in the brain. He also considers physical world as a structure of tendencies and probabilities. He speaks about creative events which occur among Heisenberg probability distributions. On... 

The question of the time is one of the obscure and challenging subjects which has been discussed as a mysterious problem in various civilizations. In ancient Greece, the question has been debated among the supporters of existence and eternity. We observe the words of Plato, on the existence of the absolute essence of eternity against the change and transition time instantiated as a conducted river in the Heraclitus view. Other discussions focused on the relationship between the change and displacement, or the the spatial relations to which Aristotle paid attention. With the passing of time from the ancient and medieval eras to the Renaissance period, along with the growth of the science in... 

Chaos is defined as an unpredictable and unrepeatable motion which has been observed in many classical systems such as unharmonic oscillators and turbulent currents in fluids. The common aspect of these types of motions is the deterministic nonlinear equation. On the other hand, quantum mechanics is a stochastic theory which is based on probabilistic description of quantum systems. These approaches lead to quantum chaos phenomenon which has been a controversial issue in the recent years. In the thesis, by studying the classical chaotic models such as kicked rotor, billiard model, excited hydrogen atom under microwave field and etc, we examine the existence of chaotic behavior in quantum... 

In the present era consciousness problem and the relationship between mind and matter as one of the historical and difficult philosophical issues has entered in different scientific fields such as neuroscience, cognitive science and physics. With the introduction of quantum theory and offering its different interpretations, some claimed that understanding the consciousness problem will be possible in the light of quantum theory and some claimed that consciousness is necessary for correct understanding of the quantum theory. Henry Stapp and David Bohm, two prominent physicists with two different approaches to quantum theory try to describe this problem from their point of view. Henry Stapp... 

Considering the consistency between the predictions of a theory with what is observed in experience, Quantum Mechanics is the most accurate theory in the history of physics. However, is does not present us an unmbigiuos and realistic description about the nature of the microscopic phenomena. At the heart of these issues is the so-called measurement problem. The formalism of the quantum mechanics is unitary and deterministic. Nevertheles, when one does measurements, the unitary process of the evolution of wave-function breaks due to a stochastic abruption. The results of the measurements are in correspondence with the everyday experience of the observer. Yet, the theory itself does not... 

Studying the puzzling aspects of quantum phenomenon is quite important subject from different points of view. It must be specially regarded through some major aspects such as: wave-particle dualty, Bell’s theorem no-go theorems, complementarity, entanglement and measurement problem. In this project, we survey subsequently the above topics with a careful attention regarding the measurement problem. One of the most relevant ways claiming to solve measurement problem is the decoherence theory. Scrutinizing the details of formalism and description basis of decoherence, we critically explain and asses the different aspects of this theory  

Quantum correlations are among most intriguing problems in physics. Bell’s inequality which was proved in 1964 provides with us the possibility of comparing the predictions of quantum theory with what an underlying local realistic theory may reproduce for some given observables in correlated states. The violation of Bell’s inequality in practice prohibits the existance of such underlying theories. Yet, it is not clear which of the assumption, i.e., locality or reality is responsible for explaining the experimentally verified violations. In 2003, a Nobel prizewinner A. J. Leggett proved a new inequality in which the locality assumption was not crucial. Here, we explore different aspects of... 

Different information theories have been provided in recent decades because of the numerous applications of information notion in different fields of sciences. Meanwhile, pragmatic theory of information is one of the most common concepts in this field which has been studied remarkably in recent decades. Different aspects of this theory (in J. G. Roederer’s sense of attitude) are critically assessed in this thesis. Roederer considers the information as a relative concept in which interaction plays fundamental role. Moreover, information is an agent which leads to an univocal correspondence between the sender and the recipient, so that the presence of a certain spatial or temporal pattern... 

New biological discussions in quantum mechanics that has grown considerably in the past decade. Meanwhile, considering some of interesting problems in biology and chemistry, the use of quantum approach superposition principle and tunneling effect explain some of the phenomena of life more than several. Nowadays, regarding quantum description, provided to explain how we recognize different odors, what the mechanism photosynthesis is, and how bind navigation occurs. Furthermore, the new field of quantum biology sheds light in underestanding the issue of heritance and genetics inforamtion. In this thesis, after reviewing some interesting topics of quantum biology, the data transfer from... 

Quantum Theory leads to results that are consistent with the very high accuracy with experience and also includes a wide range of empirical phenomena. Hence, quantum mechanics is accepted as the best and most acclaimed physical theory. However, there is still no consensus between physicists on the interpretation of parts of this theory. One of the unresolved issues in quantum mechanics is the measurement problem. The basis of the measurement problem is a kind of transition from the quantum world to the classical world. The fundamental question that arises here is, where is the boundary between quantum mechanics and classical mechanics? and how can be described the transition from quantum... 

In the early days of quantum mechanics it seemed that, this theory is presented to describe atoms and molecules. As the time went on, by distinguishing different applications of quantum mechanics a question raised in scientists minds. Is it possible to see strange quantum effects in every day life. In this regard several attempt have been made to see such properties. One of these phenomena is observing interference effects for Fulleren molecules. In this thesis we investigate different properties of a macroscopic quantum system in different situations. We showed that an asymmetric double well potential, which is a macroscopic quantum system in interaction with environment violates... 

Undoubtedly, the concept of information has an outstanding role in our description of physical systems and biological processes. In the framework of pragmatic approach, information is a useful notion through which any physical event gets its significance. In this approach, information can be understood and recognized while it is capable of producing new information. Thus, the meaning of information depends on our recognition and understanding as conscious beings. Accordingly, the following question may arise: where is the role of conscious being in the emergence of physical properties in Nature? To answer this fundamental question, we first investigate how information enters the physics, in... 

Although quantum mechanics has thrilled a multitude of successes since its birth, it has also generated puzzles that persist to this day. These puzzles are largely connected with the role of measurement in quantum mechanics. Therefore, we are dealing with individual phenomena and that our possibilities of handling the measuring instruments allow us only to make a choice between the different complementary types of phenomena. Within the framework of delayed-choice experiments, the choice between complementary types of phenomena is postponed to the moments after the preparation of system is a superposition state. Regarding the probability theory, we have concluded that the delayed-choice... 

In this study the concept of the origin of life, as an important question, is investigated and reviewed.Then the possibility of the beginning of life from an extraterrestrial origin is studied via spectroscopy methods to analyze the role of the cosmic waves.Moreover, by considering the similarity between the chirality of the essential amino acids and extraterrestrial amino acids, found in meteors the various methods for studying the structure of molecules, as well as the possibility of the transfer of the central elements of life from space to the earth are reviewed in details.Finally, we suggest how chirality might be emerged due to the interaction of the molecule with the environment,...