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Observer (quantum Physics)
Some interpretations of quantum mechanics posit a central role for an observer of a quantum phenomenon. The quantum mechanical observer is tied to the issue of Observer effect (physics)#Quantum mechanics, observer effect, where a measurement necessarily requires interacting with the physical object being measured, affecting its properties through the interaction. The term "observable" has gained a technical meaning, denoting a Hermitian operator that represents a measurement. Foundation The theoretical foundation of the concept of measurement in quantum mechanics is a contentious issue deeply connected to the many interpretations of quantum mechanics. A key focus point is that of wave function collapse, for which several popular interpretations assert that measurement causes a ''discontinuous change'' into an Eigenvalues and eigenvectors#Schr.C3.B6dinger equation, eigenstate of the operator associated with the quantity that was measured, a change which is not time-reversible. More ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpretations Of Quantum Mechanics
An interpretation of quantum mechanics is an attempt to explain how the mathematical theory of quantum mechanics might correspond to experienced reality. Quantum mechanics has held up to rigorous and extremely precise tests in an extraordinarily broad range of experiments. However, there exist a number of contending schools of thought over their interpretation. These views on interpretation differ on such fundamental questions as whether quantum mechanics is determinism, deterministic or stochastic, Principle_of_locality, local or Quantum_nonlocality, non-local, which elements of quantum mechanics can be considered real, and what the nature of measurement in quantum mechanics, measurement is, among other matters. While some variation of the Copenhagen interpretation is commonly presented in textbooks, many other interpretations have been developed. Despite nearly a century of debate and experiment, no consensus has been reached among physicists and Philosophy of physics, philosophe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Decoherence
Quantum decoherence is the loss of quantum coherence. It involves generally a loss of information of a system to its environment. Quantum decoherence has been studied to understand how quantum systems convert to systems that can be explained by classical mechanics. Beginning out of attempts to extend the understanding of quantum mechanics, the theory has developed in several directions and experimental studies have confirmed some of the key issues. Quantum computing relies on quantum coherence and is one of the primary practical applications of the concept. Concept In quantum mechanics, physical systems are described by a mathematical representation called a quantum state. Probabilities for the outcomes of experiments upon a system are calculated by applying the Born rule to the quantum state describing that system. Quantum states are either ''pure'' or ''mixed''; pure states are also known as ''wavefunctions''. Assigning a pure state to a quantum system implies certai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritjof Capra
Fritjof Capra (born February 1, 1939) is an Austrian-born American author, physicist, systems theorist and deep ecologist. In 1995, he became a founding director of the Center for Ecoliteracy in Berkeley, California. He was on the faculty of Schumacher College which was disestablished in 2024. Capra is the author of several books, including '' The Tao of Physics'' (1975), '' The Turning Point'' (1982), ''Uncommon Wisdom'' (1988), ''The Web of Life'' (1996), and '' The Hidden Connections'' (2002), and co-author of ''The Systems View of Life'' (2014). Life and work Born in Vienna, Austria, Capra attended the University of Vienna, where he earned his PhD in theoretical physics in 1966. He conducted research in particle physics and systems theory at the University of Paris (1966–1968), the University of California, Santa Cruz (1968–1970), the Stanford Linear Accelerator Center (1970), Imperial College, London (1971–1974) and the Lawrence Berkeley Laboratory (1975–198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philosophy Of Physics
In philosophy, the philosophy of physics deals with conceptual and interpretational issues in physics, many of which overlap with research done by certain kinds of theoretical physicists. Historically, philosophers of physics have engaged with questions such as the nature of space, time, matter and the laws that govern their interactions, as well as the epistemological and ontological basis of the theories used by practicing physicists. The discipline draws upon insights from various areas of philosophy, including metaphysics, epistemology, and philosophy of science, while also engaging with the latest developments in theoretical and experimental physics. Contemporary work focuses on issues at the foundations of the three pillars of modern physics: * Quantum mechanics: Interpretations of quantum theory, including the nature of quantum states, the measurement problem, and the role of observers. Implications of entanglement, nonlocality, and the quantum-classical relations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthropocentrism
Anthropocentrism ( ) is the belief that human beings are the central or most important entity on the planet. The term can be used interchangeably with humanocentrism, and some refer to the concept as human supremacy or human exceptionalism. From an anthropocentric perspective, humankind is seen as separate from nature and superior to it, and other entities (animals, plants, minerals, etc.) are viewed as resources for humans to use. It is possible to distinguish between at least three types of anthropocentrism: perceptual anthropocentrism (which "characterizes paradigms informed by sense-data from human sensory organs"); descriptive anthropocentrism (which "characterizes paradigms that begin from, center upon, or are ordered around ''Homo sapiens'' / ‘the human'"); and normative anthropocentrism (which "characterizes paradigms that make assumptions or assertions about the superiority of ''Homo sapiens'', its capacities, the primacy of its values, rits position in the universe" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Stewart Bell
John Stewart Bell (28 July 1928 – 1 October 1990) was a physicist from Northern Ireland and the originator of Bell's theorem, an important theorem in quantum mechanics, quantum physics regarding hidden-variable theory, hidden-variable theories. In 2022, the Nobel Prize in Physics was awarded to Alain Aspect, John Clauser, and Anton Zeilinger for work on Bell test, Bell inequalities and the Aspect's experiment, experimental validation of Bell's theorem. Biography Early life and work Bell was born in Belfast, Northern Ireland to a working class family. Due to financial hardship, neither parent and none of his three older siblings completed high school, typically dropping out of school by age 14 to work. When he was 11 years old, he decided to be a scientist, and encouraged by his mother, at 16 he graduated from Belfast Technical High School. Then in an exceptionally rare occurrence for someone of his background, Bell attended the Queen's University of Belfast, where, in 194 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wigner's Friend
Wigner's friend is a thought experiment in theoretical quantum physics, first published by the Hungarian-American physicist Eugene Wigner in 1961, Reprinted in and further developed by David Deutsch in 1985. The scenario involves an indirect observation of a quantum measurement: An observer W observes another observer F who performs a quantum measurement on a physical system. The two observers then formulate a statement about the physical system's state after the measurement according to the laws of quantum theory. In the Copenhagen interpretation, the resulting statements of the two observers contradict each other. This reflects a seeming incompatibility of two laws in the Copenhagen interpretation: the deterministic and continuous time evolution of the state of a closed system and the nondeterministic, discontinuous collapse of the state of a system upon measurement. Wigner's friend is therefore directly linked to the measurement problem in quantum mechanics with its famo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kluwer
Wolters Kluwer N.V. is a Dutch information services company. The company serves legal, business, tax, accounting, finance, audit, risk, compliance, and healthcare markets. Wolters Kluwer in its current form was founded in 1987 with a merger between Kluwer Publishers and Wolters Samsom. It operates in over 150 countries. The company is headquartered in Alphen aan den Rijn, Netherlands (Global). History Early history Jan-Berend Wolters founded the Schoolbook publishing house in Groningen, Netherlands, in 1836. In 1858, the Noordhoff publishing house was founded alongside the Schoolbook publishing house. The two publishing houses merged in 1968. Wolters-Noordhoff merged with Information and Communications Union (ICU) in 1972 and took the name ICU. ICU acquired Croner in 1977, ICU changed its name to Wolters-Samsom in 1983. The company began serving foreign law firms and multinational companies in China in 1985. In 1987, Elsevier, the largest publishing house in the Netherlands, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concepts And Methods
A concept is an abstract idea that serves as a foundation for more concrete principles, thoughts, and beliefs. Concepts play an important role in all aspects of cognition. As such, concepts are studied within such disciplines as linguistics, psychology, and philosophy, and these disciplines are interested in the logical and psychological structure of concepts, and how they are put together to form thoughts and sentences. The study of concepts has served as an important flagship of an emerging interdisciplinary approach, cognitive science. In contemporary philosophy, three understandings of a concept prevail: * mental representations, such that a concept is an entity that exists in the mind (a mental object) * abilities peculiar to cognitive agents (mental states) * Fregean senses, abstract objects rather than a mental object or a mental state Concepts are classified into a hierarchy, higher levels of which are termed "superordinate" and lower levels termed "subordinate". Addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Special Relativity
In physics, the special theory of relativity, or special relativity for short, is a scientific theory of the relationship between Spacetime, space and time. In Albert Einstein's 1905 paper, Annus Mirabilis papers#Special relativity, "On the Electrodynamics of Moving Bodies", the theory is presented as being based on just Postulates of special relativity, two postulates: # The laws of physics are Invariant (physics), invariant (identical) in all Inertial frame of reference, inertial frames of reference (that is, Frame of reference, frames of reference with no acceleration). This is known as the principle of relativity. # The speed of light in vacuum is the same for all observers, regardless of the motion of light source or observer. This is known as the principle of light constancy, or the principle of light speed invariance. The first postulate was first formulated by Galileo Galilei (see ''Galilean invariance''). Background Special relativity builds upon important physics ide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asher Peres
Asher Peres (; January 30, 1934 – January 1, 2005) was an Israeli physicist. Peres is best known for his work relating quantum mechanics and information theory. He helped to develop the Peres–Horodecki criterion for quantum entanglement, as well as the concept of quantum teleportation, and collaborated with others on quantum information and special relativity. He also introduced the Peres metric and researched the Hamilton–Jacobi–Einstein equation in general relativity. With Mario Feingold, he published work in quantum chaos that is known to mathematicians as the Feingold–Peres conjecture and to physicists as the Feingold–Peres theory. Life According to his autobiography, he was born ''Aristide Pressman'' in Beaulieu-sur-Dordogne in France, where his father, a Polish electrical engineer, had found work laying down power lines. He was given the name ''Aristide'' at birth, because the name his parents wanted, ''Asher'', the name of his maternal grandfather, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niels Bohr
Niels Henrik David Bohr (, ; ; 7 October 1885 – 18 November 1962) was a Danish theoretical physicist who made foundational contributions to understanding atomic structure and old quantum theory, quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research. Bohr developed the Bohr model of the atom, in which he proposed that energy levels of electrons are discrete and that the electrons revolve in stable orbits around the atomic nucleus but can jump from one energy level (or orbit) to another. Although the Bohr model has been supplanted by other models, its underlying principles remain valid. He conceived the principle of Complementarity (physics), complementarity: that items could be separately analysed in terms of contradictory properties, like behaving as a Wave–particle duality, wave or a stream of particles. The notion of complementarity dominated Bohr's thinking in both science and philoso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
