- This is a discussion of a present category of science. For the work by Aristotle, see Physics (Aristotle). Aristotle (Greek Aristotélēs) (384 BC – 322 BC was a Greek philosopher a student of Plato and teacher of Alexander the Great. Physics (or "Physica" or "Physicae Auscultationes" meaning "lessons" is a key text in the philosophy of Aristotle. For a history of the science, see History of physics. The modern discipline of Physics emerged in the 17th century following in traditions of inquiry established by Galileo Galilei, René Descartes, Isaac For the etymology of the word physics, see physis (φύσις). Physis (grc φύσις is a Greek theological, philosophical, and scientific term usually translated into English as " Nature "
Physics is the science of matter[1] and its motion,[2][3] as well as space and time. Science (from the Latin scientia, meaning " Knowledge " or "knowing" is the effort to discover, and increase human understanding Matter is commonly defined as being anything that has mass and that takes up space. In Physics, motion means a constant change in the location of a body Space is the extent within which Matter is physically extended and objects and Events have positions relative to one another For other uses see Time (disambiguation Time is a component of a measuring system used to sequence events to compare the durations of [4][5] It uses concepts such as energy, force, mass, and charge. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός In Physics, a force is whatever can cause an object with Mass to Accelerate. Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object In Physics, a charge may refer to one of many different quantities such as the Electric charge in Electromagnetism or the Color charge in Physics is an experimental science,[6] creating theories that are tested against observations. In scientific inquiry an experiment ( Latin: Ex- periri, "to try out" is a method of investigating particular types of research questions or Science (from the Latin scientia, meaning " Knowledge " or "knowing" is the effort to discover, and increase human understanding Theoretical physics employs Mathematical models and Abstractions of Physics in an attempt to explain experimental data taken of the natural world Within the field of Physics, experimental physics is the category of disciplines and sub-disciplines concerned with the Observation of physical Phenomena Broadly, it is the general scientific analysis of nature, with a goal of understanding how the universe behaves. Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. [7]
Physics is one of the oldest academic disciplines. It emerged as a modern science in the 17th century,[8] and through its modern subfield of astronomy, it may be the oldest of all. The period which many historians of science call the Scientific Revolution can be roughly dated as having begun in 1543 the year in which Nicolaus Copernicus published Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study [9] Those who work professionally in the field are known as physicists. A physicist is a Scientist who studies or practices Physics. Physicists study a wide range of physical phenomena in many branches of physics spanning
Advances in physics often translate to the technological sector, and sometimes influence the other sciences, as well as mathematics and philosophy. For example, advances in the understanding of electromagnetism have led to the widespread use of electrically driven devices (televisions, computers, home appliances etc. Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of ); advances in thermodynamics led to the development of motorized transport; and advances in mechanics led to the development of calculus, quantum chemistry, and the use of instruments such as the electron microscope in microbiology. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Mechanics ( Greek) is the branch of Physics concerned with the behaviour of physical bodies when subjected to Forces or displacements Calculus ( Latin, calculus, a small stone used for counting is a branch of Mathematics that includes the study of limits, Derivatives Quantum chemistry is a branch of Theoretical chemistry, which applies Quantum mechanics and Quantum field theory to address issues and problems in An electron microscope is a type of Microscope that uses Electrons to illuminate a specimen and create an enlarged image Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία
Today, physics is a broad and highly developed subject. Research is often divided into four subfields: condensed matter physics; atomic, molecular, and optical physics; high-energy physics; and astronomy and astrophysics. Condensed matter physics is the field of Physics that deals with the macroscopic physical properties of Matter. Atomic molecular, and optical Physics is the study of Matter -matter and Light -matter interactions on the scale of single Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them Astrophysics is the branch of Astronomy that deals with the Physics of the Universe, including the physical properties ( Luminosity, Most physicists also specialize in either theoretical or experimental research, the former dealing with the development of new theories, and the latter dealing with the experimental testing of theories and the discovery of new phenomena. Theoretical physics employs Mathematical models and Abstractions of Physics in an attempt to explain experimental data taken of the natural world Within the field of Physics, experimental physics is the category of disciplines and sub-disciplines concerned with the Observation of physical Phenomena Despite important discoveries during the last four centuries, there are a number of unsolved problems in physics, and many areas of active research. This is a list of some of the major unsolved problems in Physics.
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Branches of Physics
Although physics encompasses a wide variety of phenomena, the fundamental branches of physics are classical mechanics, electromagnetism (including optics), relativity, thermodynamics, and quantum mechanics. Classical mechanics is used for describing the motion of Macroscopic objects from Projectiles to parts of Machinery, as well as Astronomical objects Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of This page is about the scientific concept of relativity for philosophical or sociological theories about relativity see Relativism. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons Each of these theories has been tested in numerous experiments and proven to be an accurate model of nature within its domain of validity. For example, classical mechanics correctly describes the motion of objects in everyday experience, but it breaks down at the atomic scale, where it is superseded by quantum mechanics, and at speeds approaching the speed of light, where relativistic effects become important. Classical mechanics is used for describing the motion of Macroscopic objects from Projectiles to parts of Machinery, as well as Astronomical objects Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial While these theories have long been well-understood, they continue to be areas of active research — for example, a remarkable aspect of classical mechanics known as chaos theory was developed in the 20th century, three centuries after the original formulation of mechanics by Isaac Newton (1642–1727). In Mathematics, chaos theory describes the behavior of certain dynamical systems – that is systems whose state evolves with time – that may exhibit dynamics that The basic theories form a foundation for the study and research of more specialized topics. A table of these theories, along with many of the concepts they employ, can be found here. The table below lists the core theories along with many of the concepts they employ
Classical mechanics
Classical mechanics is a model of the physics of forces acting upon bodies. Classical mechanics is used for describing the motion of Macroscopic objects from Projectiles to parts of Machinery, as well as Astronomical objects In Physics, a force is whatever can cause an object with Mass to Accelerate. It is often referred to as "Newtonian mechanics" after Isaac Newton and his laws of motion. Sir Isaac Newton, FRS (ˈnjuːtən 4 January 1643 31 March 1727) Biography Early years See also Isaac Newton's early life and achievements Newton's laws of motion are three Physical laws which provide relationships between the Forces acting on a body and the motion of the Mechanics is subdivided into statics, which models objects at rest, kinematics, which models objects in motion, and dynamics, which models objects subjected to forces. Statics is the branch of Mechanics concerned with the analysis of loads ( Force, torque/moment) on Physical systems in Static equilibrium Kinematics ( Greek κινειν, kinein, to move is a branch of Classical mechanics which describes the motion of objects without In physics the term dynamics customarily refers to the time evolution of physical processes The classical mechanics of continuous and deformable objects is continuum mechanics, which can itself be broken down into solid mechanics and fluid mechanics according to the state of matter being studied. Continuum mechanics is a branch of Mechanics that deals with the analysis of the Kinematics and mechanical behavior of materials modeled as a continuum e Solid mechanics is the branch of Mechanics, Physics, and Mathematics that concerns the behavior of solid matter under external actions (e Fluid mechanics is the study of how Fluids move and the Forces on them The latter, the mechanics of liquids and gases, includes hydrostatics, hydrodynamics, pneumatics, aerodynamics, and other fields. Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of This page is about the physical properties of gas as a state of matter Fluid statics (also called hydrostatics) is the Science of Fluids at rest and is a sub-field within Fluid mechanics. Fluid dynamics is the sub-discipline of Fluid mechanics dealing with fluid flow: Fluids ( Liquids and Gases in motion Pneumatics, Pressurized gas to affect mechanical motion Pneumatic power is used in Industry, where it is common to have factory units plumbed for Compressed Mechanical Statics deals with objects at rest. Mechanical kinematics deals with objects in motion. Mechanical dynamics deals with motion by forces,of objects.
Classical mechanics produces accurate results within the domain of everyday experience. It is superseded by relativistic mechanics for systems moving at large velocities near the speed of light, quantum mechanics for systems at small distance scales, and relativistic quantum field theory for systems with both properties. This page is about the scientific concept of relativity for philosophical or sociological theories about relativity see Relativism. Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons In quantum field theory (QFT the forces between particles are mediated by other particles Nevertheless, classical mechanics is still useful, because it is much simpler and easier to apply than these other theories, and it has a very large range of approximate validity. Classical mechanics can be used to describe the motion of human-sized objects (such as tops and baseballs), many astronomical objects (such as planets and galaxies), and certain microscopic objects (such as organic molecules). A top, or spinning top, is a Toy that can be spun on an axis balancing on a point A baseball is a Ball used primarily in the sport of the same name Baseball.
An important concept of mechanics is the identification of conserved energy and momentum, which lead to the Lagrangian and Hamiltonian reformulations of Newton's laws. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός In Classical mechanics, momentum ( pl momenta SI unit kg · m/s, or equivalently N · s) is the product Lagrangian mechanics is a re-formulation of Classical mechanics that combines Conservation of momentum with Conservation of energy. Hamiltonian mechanics is a re-formulation of Classical mechanics that was introduced in 1833 by Irish mathematician William Rowan Hamilton. Theories such as fluid mechanics and the kinetic theory of gases result from applying classical mechanics to macroscopic systems. Fluid mechanics is the study of how Fluids move and the Forces on them Kinetic theory (or kinetic theory of gases) attempts to explain Macroscopic properties of Gases such as pressure temperature or volume by considering A relatively recent result of considerations concerning the dynamics of nonlinear systems is chaos theory, the study of systems in which small changes in a variable may have large effects. In Mathematics, chaos theory describes the behavior of certain dynamical systems – that is systems whose state evolves with time – that may exhibit dynamics that Newton's law of universal gravitation, formulated within classical mechanics, explained Kepler's laws of planetary motion and helped make classical mechanics an important element of the Scientific Revolution. Newton 's law of universal Gravitation is a physical law describing the gravitational attraction between bodies with mass In Astronomy, Kepler's Laws of Planetary Motion are three mathematical laws that describe the motion of Planets in the Solar System. The period which many historians of science call the Scientific Revolution can be roughly dated as having begun in 1543 the year in which Nicolaus Copernicus published
Electromagnetism
- See also: Optics
Electromagnetism describes the interaction of charged particles with electric and magnetic fields. Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of In Physics, a field is a Physical quantity associated to each point of Spacetime. It can be divided into electrostatics, the study of interactions between charges at rest, and electrodynamics, the study of interactions between moving charges and radiation. Electrostatics is the branch of Science that deals with the Phenomena arising from what seems to be stationary Electric charges Since Classical Electric charge is a fundamental conserved property of some Subatomic particles which determines their Electromagnetic interaction. Classical electromagnetism (or classical electrodynamics) is a theory of Electromagnetism that was developed over the course of the 19th century most prominently Radiation, as in Physics, is Energy in the form of waves or moving Subatomic particles emitted by an atom or other body as it changes from a higher energy The classical theory of electromagnetism is based on the Lorentz force law and Maxwell's equations. In Physics, the Lorentz force is the Force on a Point charge due to Electromagnetic fields It is given by the following equation In Classical electromagnetism, Maxwell's equations are a set of four Partial differential equations that describe the properties of the electric
Electrostatics is the study of phenomena associated with charged bodies at rest. Electrostatics is the branch of Science that deals with the Phenomena arising from what seems to be stationary Electric charges Since Classical As described by Coulomb’s law, such bodies exert forces on each other. ---- Bold text Coulomb's law', developed in the 1780s by French physicist Charles Augustin de Coulomb, may be stated in scalar form In Physics, a force is whatever can cause an object with Mass to Accelerate. Their behavior can be analyzed in terms of the concept of an electric field surrounding any charged body, such that another charged body placed within the field is subject to a force proportional to the magnitude of its own charge and the magnitude of the field at its location. In Physics, the space surrounding an Electric charge or in the presence of a time-varying Magnetic field has a property called an electric field (that can Whether the force is attractive or repulsive depends on the polarity of the charge. A magnet (from Greek grc μαγνήτης λίθος " Magnesian stone" is a material or object that produces a Magnetic field. Electrostatics has many applications, ranging from the analysis of phenomena such as thunderstorms to the study of the behavior of electron tubes.
Electrodynamics is the study of phenomena associated with charged bodies in motion and varying electric and magnetic fields. Classical electromagnetism (or classical electrodynamics) is a theory of Electromagnetism that was developed over the course of the 19th century most prominently Electric charge is a fundamental conserved property of some Subatomic particles which determines their Electromagnetic interaction. In Physics, the space surrounding an Electric charge or in the presence of a time-varying Magnetic field has a property called an electric field (that can In Physics, a magnetic field is a Vector field that permeates space and which can exert a magnetic force on moving Electric charges Since a moving charge produces a magnetic field, electrodynamics is concerned with effects such as magnetism, electromagnetic radiation, and electromagnetic induction, including such practical applications as the electric generator and the electric motor. Radiation, as in Physics, is Energy in the form of waves or moving Subatomic particles emitted by an atom or other body as it changes from a higher energy Faraday's law of induction describes an important basic law of electromagnetism which is involved in the working of Transformers Inductors and many forms of In Electricity generation, an electrical generator is a device that converts Mechanical energy to Electrical energy, generally using Electromagnetic An electric motor uses Electrical energy to produce Mechanical energy. This area of electrodynamics, known as classical electrodynamics, was first systematically explained by James Clerk Maxwell, and Maxwell’s equations describe the phenomena of this area with great generality. James Clerk Maxwell (13 June 1831 &ndash 5 November 1879 was a Scottish mathematician and theoretical physicist. A more recent development is quantum electrodynamics, which incorporates the laws of quantum theory in order to explain the interaction of electromagnetic radiation with matter. Quantum electrodynamics ( QED) is a relativistic Quantum field theory of Electrodynamics. In quantum field theory (QFT the forces between particles are mediated by other particles Dirac, Heisenberg, and Pauli were pioneers in the formulation of quantum electrodynamics. Werner Heisenberg (5 December 1901 in Würzburg &ndash1 February 1976 in Munich) was a German theoretical physicist best known for enunciating the Relativistic electrodynamics accounts for relativistic corrections to the motions of charged particles when their speeds approach the speed of light. Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial It applies to phenomena involved with particle accelerators and electron tubes carrying high voltages and currents. In Physics, the potential difference or pd between two points is the difference of the points' Scalar potential, equivalent to the line integral Electric current is the flow (movement of Electric charge. The SI unit of electric current is the Ampere.
Electromagnetism encompasses various real-world electromagnetic phenomena. A phenomenon (from Greek φαινόμενoν, pl φαινόμενα - phenomena) is any observable occurrence For example, light is an oscillating electromagnetic field that is radiated from accelerating charged particles. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 The electromagnetic field is a physical field produced by electrically charged objects. Aside from gravity, most of the forces in everyday experience are ultimately a result of electromagnetism. Gravitation is a natural Phenomenon by which objects with Mass attract one another
The principles of electromagnetism find applications in various allied disciplines such as microwaves, antennas, electric machines, satellite communications, bioelectromagnetics, plasmas, nuclear research, fiber optics, electromagnetic interference and compatibility, electromechanical energy conversion, radar meteorology, and remote sensing. Microwaves are electromagnetic waves with Wavelengths ranging from 1 mm to 1 m or frequencies between 0 An antenna is a Transducer designed to transmit or Receive electromagnetic waves In other words antennas convert electromagnetic waves into A communications satellite (sometimes abbreviated to comsat) is an artificial Satellite stationed in space for the purposes of Telecommunications. In Physics and Chemistry, plasma is an Ionized Gas, in which a certain proportion of Electrons are free rather than being bound Nuclear physics is the field of Physics that studies the building blocks and interactions of Atomic nuclei. An optical fiber (or fibre) is a Glass or Plastic fiber that carries Light along its length Radar is a system that uses electromagnetic waves to identify the range altitude direction or speed of both moving and fixed objects such as Aircraft, ships Meteorology (from Greek grc μετέωρος metéōros, "high in the sky" and grc -λογία -logia) is the Interdisciplinary Remote sensing is the small or large-scale acquisition of information of an object or phenomenon by the use of either recording or real-time sensing device(s that is not in physical Electromagnetic devices include transformers, electric relays, radio/TV, telephones, electric motors, transmission lines, waveguides, optical fibers, and lasers. A transformer is a device that transfers Electrical energy from one circuit to another through inductively coupled Electrical conductors A relay is an electrical Switch that opens and closes under the control of another Electrical circuit. Radio is the transmission of signals by Modulation of electromagnetic waves with frequencies below those of visible Light. Television ( TV) is a widely used Telecommunication medium for sending ( Broadcasting) and receiving moving Images, either monochromatic Basic principle A traditional landline telephone system also known as "plain old telephone service" (POTS, commonly handles both signaling and audio information An electric motor uses Electrical energy to produce Mechanical energy. A transmission line is the material medium or structure that forms all or part of a path from one place to another for directing the transmission of energy A waveguide is a structure which guides waves such as Electromagnetic waves Light, or Sound waves An optical fiber (or fibre) is a Glass or Plastic fiber that carries Light along its length A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission.
Relativity
Relativity is a generalization of classical mechanics that describes fast-moving or very massive systems. This page is about the scientific concept of relativity for philosophical or sociological theories about relativity see Relativism. It includes special and general relativity. Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial General relativity or the general theory of relativity is the geometric theory of Gravitation published by Albert Einstein in 1916
The theory of special relativity was proposed in 1905 by Albert Einstein in his article "On the Electrodynamics of Moving Bodies". Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial Year 1905 ( MCMV) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar (or a Common year starting Albert Einstein ( German: ˈalbɐt ˈaɪ̯nʃtaɪ̯n; English: ˈælbɝt ˈaɪnstaɪn (14 March 1879 – 18 April 1955 was a German -born theoretical The Annus Mirabilis Papers (from Latin, Annus mirabilis, for 'extraordinary year' are the papers of Albert Einstein published in the " The title of the article refers to the fact that special relativity resolves an inconsistency between Maxwell's equations and classical mechanics. In Classical electromagnetism, Maxwell's equations are a set of four Partial differential equations that describe the properties of the electric The theory is based on two postulates: (1) that the mathematical forms of the laws of physics are invariant in all inertial systems; and (2) that the speed of light in a vacuum is constant and independent of the source or observer. See also Special relativity Postulates of special relativity 1 A physical law or scientific law is a Scientific generalization based on empirical Observations of physical behavior (i In Physics, an inertial frame of reference is a Frame of reference which belongs to a set of frames in which Physical laws hold in the same and simplest This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. Reconciling the two postulates requires a unification of space and time into the frame-dependent concept of spacetime. Space is the extent within which Matter is physically extended and objects and Events have positions relative to one another For other uses see Time (disambiguation Time is a component of a measuring system used to sequence events to compare the durations of SpaceTime is a patent-pending three dimensional graphical user interface that allows end users to search their content such as Google Google Images Yahoo! YouTube eBay Amazon and RSS
Special relativity has a variety of surprising consequences that seem to violate common sense, but all have been experimentally verified. It overthrows Newtonian notions of absolute space and time by stating that distance and time depend on the observer, and that time and space are perceived differently, depending on the observer. Classical mechanics is used for describing the motion of Macroscopic objects from Projectiles to parts of Machinery, as well as Astronomical objects For other uses see Time (disambiguation Time is a component of a measuring system used to sequence events to compare the durations of The theory leads to the assertion of change in mass, dimension, and time with increased velocity. Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object In mathematics the dimension of a Space is roughly defined as the minimum number of Coordinates needed to specify every point within it For other uses see Time (disambiguation Time is a component of a measuring system used to sequence events to compare the durations of In Physics, velocity is defined as the rate of change of Position. It also yields the equivalence of matter and energy, as expressed in the mass-energy equivalence formula E = mc2, where c is the speed of light in a vacuum. Matter is commonly defined as being anything that has mass and that takes up space. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός In Physics, mass–energy equivalence is the concept that for particles slower than light any Mass has an associated Energy and vice versa. Special relativity and the Galilean relativity of Newtonian mechanics agree when velocities are small compared to the speed of light. Galilean invariance or Galilean relativity is a Principle of relativity which states that the fundamental laws of physics are the same in all Inertial Special relativity does not describe gravitation; however, it can handle accelerated motion in the absence of gravitation. [10]
General relativity is the geometrical theory of gravitation published by Albert Einstein in 1915/16. General relativity or the general theory of relativity is the geometric theory of Gravitation published by Albert Einstein in 1916 Geometry ( Greek γεωμετρία; geo = earth metria = measure is a part of Mathematics concerned with questions of size shape and relative position The word theory has many distinct meanings in different fields of Knowledge, depending on their methodologies and the context of discussion. Gravitation is a natural Phenomenon by which objects with Mass attract one another Albert Einstein ( German: ˈalbɐt ˈaɪ̯nʃtaɪ̯n; English: ˈælbɝt ˈaɪnstaɪn (14 March 1879 – 18 April 1955 was a German -born theoretical [11][12] It unifies special relativity, Newton's law of universal gravitation, and the insight that gravitation can be described by the curvature of space and time. Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial Newton 's law of universal Gravitation is a physical law describing the gravitational attraction between bodies with mass In Mathematics, curvature refers to any of a number of loosely related concepts in different areas of geometry Space is the extent within which Matter is physically extended and objects and Events have positions relative to one another For other uses see Time (disambiguation Time is a component of a measuring system used to sequence events to compare the durations of In general relativity, the curvature of space-time is produced by the energy of matter and radiation. SpaceTime is a patent-pending three dimensional graphical user interface that allows end users to search their content such as Google Google Images Yahoo! YouTube eBay Amazon and RSS In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός General relativity is distinguished from other metric theories of gravitation by its use of the Einstein field equations to relate space-time content and space-time curvature. In Mathematics, a metric or distance function is a function which defines a Distance between elements of a set. The Einstein field equations ( EFE) or Einstein's equations are a set of ten equations in Einstein 's theory of General relativity in which the Local Lorentz Invariance requires that the manifolds described in GR be 4-dimensional and Lorentzian instead of Riemannian. Hendrik Antoon Lorentz ( July 18, 1853 &ndash February 4, 1928) was a Dutch Physicist who shared the 1902 Nobel In Riemannian geometry, a Riemannian manifold ( M, g) (with Riemannian metric g) is a real Differentiable manifold M In addition, the principle of general covariance forces that mathematics be expressed using tensor calculus. In Theoretical physics, general covariance (also known as Diffeomorphism covariance or general invariance) is the Invariance of the History The word tensor was introduced in 1846 by William Rowan Hamilton to describe the norm operation in a certain type of algebraic system (eventually
The first success of general relativity was in explaining the anomalous perihelion precession of Mercury. In Celestial mechanics, an apsis, plural apsides (ˈæpsɨdɪːz is the point of greatest or least distance of the Elliptical orbit of an object from Precession refers to a change in the direction of the axis of a rotating object Then in 1919, Sir Arthur Eddington announced that observations of stars near the eclipsed Sun confirmed general relativity's prediction that massive objects bend light. Sir Arthur Stanley Eddington, OM (28 December 1882 – 22 November 1944 was an English Astrophysicist of the early 20th century A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth An eclipse is an astronomical event that occurs when one Celestial object moves into the shadow of another The Sun (Sol is the Star at the center of the Solar System. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 Since then, many other observations and experiments have confirmed many of the predictions of general relativity, including gravitational time dilation, the gravitational redshift of light, signal delay, and gravitational radiation. At its introduction in 1915 the general theory of relativity did not have a solid empirical foundation Gravitational time dilation is the effect of time passing at different rates in regions of different Gravitational potential; the higher the local distortion of Spacetime In Physics, Light or other forms of Electromagnetic radiation of a certain wavelength originating from a source placed in a region of stronger gravitational The Shapiro time delay effect or gravitational time delay effect is one of the four classic solar system Tests of general relativity. In Physics, a gravitational wave is a Fluctuation in the Curvature of Spacetime which propagates as a wave, traveling outward from In addition, numerous observations are interpreted as confirming one of general relativity's most mysterious and exotic predictions, the existence of black holes. A black hole is a theoretical region of space in which the Gravitational field is so powerful that nothing not even Electromagnetic radiation (e
Thermodynamics and statistical mechanics
Thermodynamics studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale, and the transfer of energy as heat. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Statistical mechanics is the application of Probability theory, which includes mathematical tools for dealing with large populations to the field of Mechanics In Thermodynamics, a thermodynamic system, originally called a working substance, is defined as that part of the universe that is under consideration In Thermodynamics, work is the quantity of Energy transferred from one system to another without an accompanying transfer of Entropy. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface The volume of any solid plasma vacuum or theoretical object is how much three- Dimensional space it occupies often quantified numerically In Physics the word system has a technical meaning namely it is the portion of the physical Universe chosen for analysis Macroscopic is commonly used to describe physical objects that are measurable and observable by the Naked eye. In Physics, heat, symbolized by Q, is Energy transferred from one body or system to another due to a difference in Temperature [13][14] Historically, thermodynamics developed out of need to increase the efficiency of early steam engines. In Thermodynamics, the thermal efficiency (\eta_{th} \ is a dimensionless performance measure of a thermal device such as an Internal combustion A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. [15]
The starting point for most thermodynamic considerations are the laws of thermodynamics, which postulate that energy can be exchanged between physical systems as heat or work. The laws of thermodynamics, in principle describe the specifics for the transport of Heat and work in Thermodynamic processes. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός In Physics, mechanical work is the amount of Energy transferred by a Force. [16] They also postulate the existence of a quantity named entropy, which can be defined for any system. In Thermodynamics (a branch of Physics) entropy, symbolized by S, is a measure of the unavailability of a system ’s Energy [17] In thermodynamics, interactions between large ensembles of objects are studied and categorized. Central to this are the concepts of system and surroundings. In Thermodynamics, a thermodynamic system, originally called a working substance, is defined as that part of the universe that is under consideration In Thermodynamics, a thermodynamic system, originally called a working substance, is defined as that part of the universe that is under consideration A system is composed of particles, whose average motions define its properties, which in turn are related to one another through equations of state. In Physics and Thermodynamics, an equation of state is a relation between state variables More specifically an equation of state is a thermodynamic Properties can be combined to express internal energy and thermodynamic potentials, which are useful for determining conditions for equilibrium and spontaneous processes. In Thermodynamics, the internal energy of a Thermodynamic system, or a body with well-defined boundaries, denoted by U, or sometimes A thermodynamic potential is a Scalar potential function used to represent the Thermodynamic state of a system. A dynamic equilibrium occurs when two opposing Processes proceed at the same rate A spontaneous process is the time-evolution of a system in which it releases free energy (most often as heat and moves to a lower more thermodynamically stable energy state
Statistical mechanics analyzes macroscopic systems by applying statistical principles to their microscopic constituents. Statistical mechanics is the application of Probability theory, which includes mathematical tools for dealing with large populations to the field of Mechanics Macroscopic is commonly used to describe physical objects that are measurable and observable by the Naked eye. In Thermodynamics, a thermodynamic system, originally called a working substance, is defined as that part of the universe that is under consideration Statistics is a mathematical science pertaining to the collection analysis interpretation or explanation and presentation of Data. It provides a framework for relating the microscopic properties of individual atoms and molecules to the macroscopic or bulk properties of materials that can be observed in everyday life. Thermodynamics can be explained as a natural result of statistics and mechanics (classical and quantum) at the microscopic level. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " In this way, the gas laws can be derived, from the assumption that a gas is a collection of individual particles, as hard spheres with mass. This articles outlines the historical development of the laws describing ideal gases Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object Conversely, if the individual particles are also considered to have charge, then the individual accelerations of those particles will cause the emission of light. Electric charge is a fundamental conserved property of some Subatomic particles which determines their Electromagnetic interaction. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 It was these considerations which caused Max Planck to formulate his law of blackbody radiation,[18] but only with the assumption that the spectrum of radiation emitted from these particles is not continuous in frequency, but rather quantized. The Electromagnetic radiation emitted by a Black body. You may also be looking for Incandescence, the radiation from a body [19]
Quantum mechanics
Quantum mechanics is the branch of physics treating atomic and subatomic systems and their interaction with radiation in terms of observable quantities. Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons A hydrogen atom is an atom of the chemical element Hydrogen. The electrically neutral In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other In Quantum mechanics, a probability amplitude is a complex -valued function that describes an uncertain or unknown quantity Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny A subatomic particle is an elementary or composite Particle smaller than an Atom. Radiation, as in Physics, is Energy in the form of waves or moving Subatomic particles emitted by an atom or other body as it changes from a higher energy In Physics, particularly in Quantum physics, a system observable is a property of the system state that can be determined by some sequence of physical It is based on the observation that all forms of energy are released in discrete units or bundles called "quanta". Remarkably, quantum theory typically permits only probable or statistical calculation of the observed features of subatomic particles, understood in terms of wavefunctions. Probability is the likelihood or chance that something is the case or will happen Statistics is a mathematical science pertaining to the collection analysis interpretation or explanation and presentation of Data. A wave function or wavefunction is a mathematical tool used in Quantum mechanics to describe any physical system The Schrödinger equation plays the role in quantum mechanics that Newton's laws and conservation of energy serve in classical mechanics — i. In Physics, especially Quantum mechanics, the Schrödinger equation is an equation that describes how the Quantum state of a Physical system Newton's laws of motion are three Physical laws which provide relationships between the Forces acting on a body and the motion of the In Physics, the law of conservation of energy states that the total amount of Energy in an isolated system remains constant and cannot be created although it may e. , it predicts the future behavior of a dynamic system — and is a wave equation in terms of the wavefunction which predicts analytically and precisely the probability of events or outcomes. The dynamical system concept is a mathematical Formalization for any fixed "rule" which describes the Time dependence of a point's position The wave equation is an important second-order linear Partial differential equation that describes the propagation of a variety of Waves such as Sound waves
According to the older theories of classical physics, energy is treated solely as a continuous phenomenon, while matter is assumed to occupy a specific region of space and to move in a continuous manner. According to the quantum theory, energy is held to be emitted and absorbed in tiny, discrete amounts. An individual bundle or packet of energy, called a quantum (pl. quanta), thus behaves in some situations much like particles of matter; particles are found to exhibit certain wavelike properties when in motion and are no longer viewed as localized in a given region but rather as spread out to some degree. A wave is a disturbance that propagates through Space and Time, usually with transference of Energy. For example, the light, or electromagnetic radiation, emitted or absorbed by an atom has only certain frequencies (or wavelengths), as can be seen from the line spectrum associated with the chemical element represented by that atom. Frequency is a measure of the number of occurrences of a repeating event per unit Time. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. Spectroscopy was originally the study of the interaction between Radiation and Matter as a function of Wavelength (λ The quantum theory shows that those frequencies correspond to definite energies of the light quanta, or photons, and result from the fact that the electrons of the atom can have only certain allowed energy values, or levels; when an electron changes from one allowed level to another, a quantum of energy is emitted or absorbed whose frequency is directly proportional to the energy difference between the two levels. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J
The formalism of quantum mechanics was developed during the 1920s. In 1924, Louis de Broglie proposed that not only do light waves sometimes exhibit particle-like properties, as in the photoelectric effect and atomic spectra, but particles may also exhibit wavelike properties. Louis-Victor-Pierre-Raymond 7th duc de Broglie, FRS (də bʁœj ( August 15 1892 &ndash March 19 1987) was a French Two different formulations of quantum mechanics were presented following de Broglie’s suggestion. The wave mechanics of Erwin Schrödinger (1926) involves the use of a mathematical entity, the wave function, which is related to the probability of finding a particle at a given point in space. In Physics, especially Quantum mechanics, the Schrödinger equation is an equation that describes how the Quantum state of a Physical system The matrix mechanics of Werner Heisenberg (1925) makes no mention of wave functions or similar concepts but was shown to be mathematically equivalent to Schrödinger’s theory. Matrix mechanics is a formulation of Quantum mechanics created by Werner Heisenberg, Max Born, and Pascual Jordan in 1925 Werner Heisenberg (5 December 1901 in Würzburg &ndash1 February 1976 in Munich) was a German theoretical physicist best known for enunciating the A particularly important discovery of the quantum theory is the uncertainty principle, enunciated by Heisenberg in 1927, which places an absolute theoretical limit on the accuracy of certain measurements; as a result, the assumption by earlier scientists that the physical state of a system could be measured exactly and used to predict future states had to be abandoned. In Quantum physics, the Heisenberg uncertainty principle states that locating a particle in a small region of space makes the Momentum of the particle uncertain Quantum mechanics was combined with the theory of relativity in the formulation of P. A. M. Dirac (1928), which, in addition, predicted the existence of antiparticles. to most kinds of particles, there is an associated antiparticle with the same Mass and opposite Electric charge. Other developments of the theory include quantum statistics, presented in one form by Einstein and S. N. Bose (the Bose-Einstein statistics) and in another by Dirac and Enrico Fermi (the Fermi-Dirac statistics); quantum electrodynamics, concerned with interactions between charged particles and electromagnetic fields; its generalization, quantum field theory; and quantum electronics. Particle statistics refers to the particular description of particles in Statistical mechanics. Satyendra Nath Bose (/sɐθjinðrɐ nɑθ bos/ সত্যেন্দ্র নাথ বসু ( January 1, 1894 &ndash February 4, 1974 In Statistical mechanics, Bose - Einstein statistics (or more colloquially B-E statistics determines the statistical distribution of In Statistical mechanics, Fermi-Dirac statistics is a particular case of Particle statistics developed by Enrico Fermi and Paul Dirac that Quantum electrodynamics ( QED) is a relativistic Quantum field theory of Electrodynamics. In quantum field theory (QFT the forces between particles are mediated by other particles Quantum electronics is the area of Physics dealing with the effects of Quantum mechanics on the behaviour of Electrons in matter and their interactions The discovery of quantum mechanics in the early 20th century revolutionized physics, and quantum mechanics is fundamental to most areas of current research.
Research
Theory and experiment
The culture of physics research differs from most sciences in the separation of theory and experiment. The word theory has many distinct meanings in different fields of Knowledge, depending on their methodologies and the context of discussion. In scientific inquiry an experiment ( Latin: Ex- periri, "to try out" is a method of investigating particular types of research questions or Since the twentieth century, most individual physicists have specialized in either theoretical physics or experimental physics. The twentieth century of the Common Era began on Theoretical physics employs Mathematical models and Abstractions of Physics in an attempt to explain experimental data taken of the natural world Within the field of Physics, experimental physics is the category of disciplines and sub-disciplines concerned with the Observation of physical Phenomena The great Italian physicist Enrico Fermi (1901–1954), who made fundamental contributions to both theory and experimentation in nuclear physics, was a notable exception. Italy (Italia officially the Italian Republic, (Repubblica Italiana is located on the Italian Peninsula in Southern Europe, and on the two largest Year 1901 ( MCMI) was a Common year starting on Tuesday (link will display calendar of the Gregorian calendar (or a Common year starting Year 1954 ( MCMLIV) was a Common year starting on Friday (link will display full 1954 Gregorian calendar) Nuclear physics is the field of Physics that studies the building blocks and interactions of Atomic nuclei. In contrast, almost all the successful theorists in biology and chemistry (e. Foundations of modern biology There are five unifying principles Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties g. American quantum chemist and biochemist Linus Pauling) have also been experimentalists, although this is changing as of late. Quantum chemistry is a branch of Theoretical chemistry, which applies Quantum mechanics and Quantum field theory to address issues and problems in Biochemistry is the study of the chemical processes in living Organisms It deals with the Structure and function of cellular components such as Linus Carl Pauling (February 28 1901 – August 19 1994 was an American Scientist, Peace activist, Author and educator.
Theorists seek to develop mathematical models that both agree with existing experiments and successfully predict future results, while experimentalists devise and perform experiments to test theoretical predictions and explore new phenomena. Note The term model has a different meaning in Model theory, a branch of Mathematical logic. Although theory and experiment are developed separately, they are strongly dependent upon each other. Progress in physics frequently comes about when experimentalists make a discovery that existing theories cannot explain, or when new theories generate experimentally testable predictions. Theorists working closely with experimentalists frequently employ phenomenology. The term phenomenology in Science is used to describe a body of knowledge which relates several different empirical observations of phenomena to each other
Theoretical physics is closely related to mathematics, which provides the language of physical theories, and large areas of mathematics, such as calculus, have been invented specifically to solve problems in physics. Theoretical physics employs Mathematical models and Abstractions of Physics in an attempt to explain experimental data taken of the natural world Mathematics is the body of Knowledge and Academic discipline that studies such concepts as Quantity, Structure, Space and Calculus ( Latin, calculus, a small stone used for counting is a branch of Mathematics that includes the study of limits, Derivatives Theorists may also rely on numerical analysis and computer simulations, which play an ever richer role in the formulation of physical models. The word theory has many distinct meanings in different fields of Knowledge, depending on their methodologies and the context of discussion. Numerical analysis is the study of Algorithms for the problems of continuous mathematics (as distinguished from Discrete mathematics) Simulation is the imitation of some real thing state of affairs or process The fields of mathematical and computational physics are active areas of research. Mathematical physics is the scientific discipline concerned with the interface of Mathematics and Physics. Computational physics is the study and implementation of numerical Algorithms in order to solve problems in Physics for which a quantitative theory already exists Theoretical physics has historically rested on philosophy and metaphysics; electromagnetism was unified this way. Philosophy is the study of general problems concerning matters such as existence knowledge truth beauty justice validity mind and language Metaphysics is the branch of Philosophy investigating principles of reality transcending those of any particular science [20] Thus physicists may speculate with multidimensional spaces and parallel universes, and from this, hypothesize theories. The many-worlds interpretation or MWI (also known as relative state formulation, theory of the universal wavefunction, parallel universes,
Experimental physics informs, and is informed by, engineering and technology. In scientific inquiry an experiment ( Latin: Ex- periri, "to try out" is a method of investigating particular types of research questions or Engineering is the Discipline and Profession of applying technical and scientific Knowledge and Technology is a broad concept that deals with a Species ' usage and knowledge of Tools and Crafts and how it affects a species' ability to control and adapt Experimental physicists involved in basic research design and perform experiments with equipment such as particle accelerators and lasers, whereas those involved in applied research often work in industry, developing technologies such as magnetic resonance imaging (MRI) and transistors. Basic Research is an Herbal supplement and cosmetics manufacturer based in Salt Lake City, Utah that distributes products through a large number of A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. Applied research: is Research accessing and using some part of the research communities' (the Academy 's accumulated theories knowledge methods and techniques In Electronics, a transistor is a Semiconductor device commonly used to amplify or switch electronic signals Feynman has noted that experimentalists may seek areas which are not well explored by theorists.
Research fields
Contemporary research in physics can be broadly divided into condensed matter physics; atomic, molecular, and optical physics; particle physics; astrophysics; geophysics and biophysics. Condensed matter physics is the field of Physics that deals with the macroscopic physical properties of Matter. Atomic molecular, and optical Physics is the study of Matter -matter and Light -matter interactions on the scale of single Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them Astrophysics is the branch of Astronomy that deals with the Physics of the Universe, including the physical properties ( Luminosity, Geophysics, a major discipline of Earth sciences, is the study of the Earth by quantitative physical methods especially by seismic, electromagnetic Biophysics (also biological physics) is an Interdisciplinary Science that employs and develops theories and methods of the Physical sciences for Some physics departments also support research in Physics education. Physics education refers both to the methods currently used to teach Physics and to an area of pedagogical research that seeks to improve those methods Since the twentieth century, the individual fields of physics have become increasingly specialized, and today most physicists work in a single field for their entire careers. The twentieth century of the Common Era began on "Universalists" such as Albert Einstein (1879–1955) and Lev Landau (1908–1968), who worked in multiple fields of physics, are now very rare. Albert Einstein ( German: ˈalbɐt ˈaɪ̯nʃtaɪ̯n; English: ˈælbɝt ˈaɪnstaɪn (14 March 1879 – 18 April 1955 was a German -born theoretical Year 1879 ( MDCCCLXXIX) was a Common year starting on Wednesday (link will display the full calendar of the Gregorian calendar (or a Common Year 1955 ( MCMLV) was a Common year starting on Saturday (link displays the 1955 Gregorian calendar) Lev Davidovich Landau ( Russian language: Ле́в Дави́дович Ланда́у ( January 22, 1908 &ndash April 1, 1968 Year 1908 ( MCMVIII) was a Leap year starting on Wednesday (link will display the full calendar of the Gregorian calendar (or a Leap year Year 1968 ( MCMLXVIII) was a Leap year starting on Monday (link will display full calendar of the Gregorian calendar. [21] A table of the major fields of physics, along with their subfields and the theories they employ, can be found here. The table below lists many of the fields and subfields of physics along with the theories and concepts they employ
Condensed matter
Condensed matter physics is the field of physics that deals with the macroscopic physical properties of matter. Condensed matter physics is the field of Physics that deals with the macroscopic physical properties of Matter. Rubidium (ruːˈbɪdiəm /rəˈbɪdiəm/ is a Chemical element with the symbol Rb and Atomic number 37 A Bose–Einstein condensate (BEC is a State of matter of Bosons confined in an external Potential and cooled to Temperatures very near to Condensed matter physics is the field of Physics that deals with the macroscopic physical properties of Matter. Matter is commonly defined as being anything that has mass and that takes up space. In particular, it is concerned with the "condensed" phases that appear whenever the number of constituents in a system is extremely large and the interactions between the constituents are strong. In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties The most familiar examples of condensed phases are solids and liquids, which arise from the bonding and electromagnetic force between atoms. Solid-state physics, the largest branch of Condensed matter physics, is the study of rigid Matter, or Solids The bulk of solid-state physics theory and Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of In Physics, the electromagnetic force is the force that the Electromagnetic field exerts on electrically charged particles History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny More exotic condensed phases include the superfluid and the Bose-Einstein condensate found in certain atomic systems at very low temperature, the superconducting phase exhibited by conduction electrons in certain materials, and the ferromagnetic and antiferromagnetic phases of spins on atomic lattices. Superfluidity is a phase of matter or description of Heat capacity in which unusual effects are observed when Liquids, typically of Helium-4 A Bose–Einstein condensate (BEC is a State of matter of Bosons confined in an external Potential and cooled to Temperatures very near to Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Superconductivity is a phenomenon occurring in certain Materials generally at very low Temperatures characterized by exactly zero electrical resistance Electrical conduction is the movement of electrically charged particles through a Transmission medium ( Electrical conductor) Ferromagnetism is the basic mechanism by which certain materials (such as Iron) form Permanent magnets and/or exhibit strong interactions with Magnets it In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules usuallyrelated to the spins of Electrons align in a regular pattern with neighboring In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal.
Condensed matter physics is by far the largest field of contemporary physics. Much progress has also been made in theoretical condensed matter physics. By one estimate, one third of all American physicists identify themselves as condensed matter physicists. A physicist is a Scientist who studies or practices Physics. Physicists study a wide range of physical phenomena in many branches of physics spanning Historically, condensed matter physics grew out of solid-state physics, which is now considered one of its main subfields. Solid-state physics, the largest branch of Condensed matter physics, is the study of rigid Matter, or Solids The bulk of solid-state physics theory and The term condensed matter physics was apparently coined by Philip Anderson when he renamed his research group — previously solid-state theory — in 1967. Philip Warren Anderson (born December 13, 1923) is an American Physicist. In 1978, the Division of Solid State Physics at the American Physical Society was renamed as the Division of Condensed Matter Physics. The American Physical Society was founded in 1899 and is the World 's second largest organization of physicists behind the Deutsche Physikalische Gesellschaft. [22] Condensed matter physics has a large overlap with chemistry, materials science, nanotechnology and engineering. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Materials Science or Materials Engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of Science and Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular Engineering is the Discipline and Profession of applying technical and scientific Knowledge and
Atomic, molecular, and optical
Atomic, molecular, and optical physics (AMO) is the study of matter-matter and light-matter interactions on the scale of single atoms or structures containing a few atoms. History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by Matter is commonly defined as being anything that has mass and that takes up space. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny The three areas are grouped together because of their interrelationships, the similarity of methods used, and the commonality of the energy scales that are relevant. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός All three areas include both classical and quantum treatments; they can treat their subject from a microscopic view (in contrast to a macroscopic view). Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons
Atomic physics studies the electron hull of atoms. Atomic physics (or atom physics) is the field of Physics that studies atoms as an isolated system of Electrons and an atomic nucleus. The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny Current research focuses on activities in quantum control, cooling and trapping of atoms and ions, low-temperature collision dynamics, the collective behavior of atoms in weakly interacting gases (Bose-Einstein Condensates and dilute Fermi degenerate systems), precision measurements of fundamental constants, and the effects of electron correlation on structure and dynamics. Atomic physics is influenced by the nucleus (see, e. The nucleus of an Atom is the very dense region consisting of Nucleons ( Protons and Neutrons, at the center of an atom g. , hyperfine splitting), but intra-nuclear phenomenon such as fission and fusion are considered part of high energy physics. In Atomic physics, hyperfine coupling is the weak magnetic interaction between Electrons and nuclei. Nuclear fission is the splitting of the nucleus of an atom into parts (lighter nuclei) often producing Free neutrons and other smaller nuclei which may In Physics and Nuclear chemistry, nuclear fusion is the process by which multiple- like charged atomic nuclei join together to form a heavier nucleus Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them
Molecular physics focuses on multi-atomic structures and their internal and external interactions with matter and light. Molecular physics is the study of the physical properties of Molecules and of the Chemical bonds between Atoms that bind them Optical physics is distinct from optics in that it tends to focus not on the control of classical light fields by macroscopic objects, but on the fundamental properties of optical fields and their interactions with matter in the microscopic realm. Optical physics, or optical science, is a subfield of Atomic molecular and optical physics. The optical field is a term used in physics and vector calculus to designate the electric field shown as E in the Electromagnetic wave equation which can be derived
High energy/particle physics
Particle physics is the study of the elementary constituents of matter and energy, and the interactions between them. Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them In Particle physics, an elementary particle or fundamental particle is a particle not known to have substructure that is it is not known to be made Matter is commonly defined as being anything that has mass and that takes up space. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός It may also be called "high energy physics", because many elementary particles do not occur naturally, but are created only during high energy collisions of other particles, as can be detected in particle accelerators. A collision is an isolated event in which two or more bodies (colliding bodies exert relatively strong forces on each other for a relatively short time
Currently, the interactions of elementary particles are described by the Standard Model. The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles The model accounts for the 12 known particles of matter that interact via the strong, weak, and electromagnetic fundamental forces. In particle physics the strong interaction, or strong force, or color force, holds Quarks and Gluons together to form Protons and The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four Fundamental interactions of nature Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of In Physics, a fundamental interaction or fundamental force is a mechanism by which particles interact with each other and which cannot be explained in terms Dynamics are described in terms of matter particles exchanging messenger particles that carry the forces. These messenger particles are known as gluons, W− and W+ and Z bosons, and the photons, respectively. Gluons ( Glue and the suffix -on) are Elementary particles that cause Quarks to interact and are indirectly responsible for the The W and Z bosons are the Elementary particles that mediate the Weak force. The W and Z bosons are the Elementary particles that mediate the Weak force. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena The Standard Model also predicts a particle known as the Higgs boson, the existence of which has not yet been verified. The Higgs Boson is a hypothetical massive scalar Elementary particle predicted to exist by the Standard Model of Particle physics In Particle physics, bosons are particles which obey Bose-Einstein statistics; they are named after Satyendra Nath Bose and Albert Einstein
Astrophysics
Astrophysics and astronomy are the application of the theories and methods of physics to the study of stellar structure, stellar evolution, the origin of the solar system, and related problems of cosmology. Astrophysics is the branch of Astronomy that deals with the Physics of the Universe, including the physical properties ( Luminosity, Physical cosmology, as a branch of Astronomy, is the study of the large-scale structure of the Universe and is concerned with fundamental questions about its The Universe is defined as everything that Physically Exists: the entirety of Space and Time, all forms of Matter, Energy The Hubble Ultra Deep Field, or HUDF, is an image of a small region of space in the constellation Fornax, composited from Hubble Space Telescope Astrophysics is the branch of Astronomy that deals with the Physics of the Universe, including the physical properties ( Luminosity, Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Stars of different mass and age have varying internal structures. Stellar evolution is the process by which a Star undergoes a sequence of radical changes during its lifetime The Solar System consists of the Sun and those celestial objects bound to it by Gravity. Physical cosmology, as a branch of Astronomy, is the study of the large-scale structure of the Universe and is concerned with fundamental questions about its Because astrophysics is a broad subject, astrophysicists typically apply many disciplines of physics, including mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics.
Astrophysics developed from the ancient science of astronomy. Astronomers of early civilizations performed methodical observations of the night sky, and astronomical artifacts have been found from much earlier periods. After centuries of developments by Babylonian and Greek astronomers, western astronomy lay dormant for fourteen centuries until Nicolaus Copernicus modified the Ptolemaic system by placing the sun at the center of the universe. In Astronomy, the geocentric model of the Universe is the superseded theory that the Earth is the center of the universe and other Tycho Brahe's detailed observations led to Kepler's laws of planetary motion, and Galileo's telescope helped the discipline develop into a modern science. Tycho Brahe, born Tyge Ottesen Brahe ( December 14 1546 &ndash October 24 1601) was a Danish nobleman In Astronomy, Kepler's Laws of Planetary Motion are three mathematical laws that describe the motion of Planets in the Solar System. Galileo Galilei (15 February 1564 &ndash 8 January 1642 was a Tuscan ( Italian) Physicist, Mathematician, Astronomer, and Philosopher A telescope is an instrument designed for the observation of remote objects and the collection of Electromagnetic radiation. Isaac Newton's theory of universal gravitation provided a physical, dynamic basis for Kepler's laws. By the early 19th cent. , the science of celestial mechanics had reached a highly developed state at the hands of Leonhard Euler, J. L. Lagrange, P. S. Laplace, and others. Powerful new mathematical techniques allowed solution of most of the remaining problems in classical gravitational theory as applied to the solar system. At the end of the 19th century, the discovery of spectral lines in sunlight proved that the chemical elements found in the Sun were also found on Earth. The 19th century of the Common Era began on January 1, 1801 and ended on December 31, 1900, according to the Gregorian calendar A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range compared Interest shifted from determining the positions and distances of stars to studying their physical composition (see stellar structure and stellar evolution). Stars of different mass and age have varying internal structures. Stellar evolution is the process by which a Star undergoes a sequence of radical changes during its lifetime Because the application of physics to astronomy became increasingly important throughout the 20th century, the distinction between astronomy and astrophysics has faded. The twentieth century of the Common Era began on Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Astrophysics is the branch of Astronomy that deals with the Physics of the Universe, including the physical properties ( Luminosity,
The discovery by Karl Jansky in 1931 that radio signals were emitted by celestial bodies initiated the science of radio astronomy. Karl Guthe Jansky ( October 22, 1905 &ndash February 14, 1950) was an American Physicist and Radio Engineer Radio astronomy is a subfield of Astronomy that studies celestial objects at radio frequencies. Most recently, the frontiers of astronomy have been expanded by space exploration. Perturbations and interference from the earth’s atmosphere make space-based observations necessary for infrared, ultraviolet, gamma-ray, and X-ray astronomy. Infrared astronomy is the branch of Astronomy and Astrophysics which deals with objects visible in Infrared (IR radiation Ultraviolet astronomy is generally used to refer to observations at Ultraviolet wavelengths between approximately 10 and 320 nanometres Gamma-ray astronomy is the astronomical study of the Cosmos with Gamma rays. X-ray astronomy is an observational branch of Astronomy, which deals with the study of X-ray emission from celestial objects The Hubble Space Telescope, launched in 1990, has made possible visual observations of a quality far exceeding those of earthbound instruments; earth-bound observatories using telescopes with adaptive optics will now be able to compensate for the turbulence of Earth's atmosphere. The Hubble Space Telescope ( HST; also known colloquially as "the Hubble" or just "Hubble" is a space telescope that was carried into Adaptive optics (AO is a Technology used to improve the performance of optical systems by reducing the effects of rapidly changing optical distortion EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 An atmosphere (from Greek ατμός - atmos, " Vapor " + σφαίρα - sphaira, " Sphere "
Physical cosmology is the study of the formation and evolution of the universe on its largest scales. Physical cosmology, as a branch of Astronomy, is the study of the large-scale structure of the Universe and is concerned with fundamental questions about its Albert Einstein’s theory of relativity plays a central role in all modern cosmological theories. In the early 20th century, Hubble's discovery that the universe was expanding, as shown by the Hubble diagram, prompted rival explanations known as the steady state universe and the Big Bang. The twentieth century of the Common Era began on Edwin Powell Hubble ( November 20, 1889 – September 28, 1953) was an American astronomer. Hubble's law is the statement in Physical cosmology that the Redshift in light coming from distant galaxies is proportional to their distance Steady state is a more general situation than Dynamic equilibrium. The Big Bang is the cosmological model of the Universe that is best supported by all lines of scientific evidence and Observation. The Big Bang was confirmed by the success of Big Bang nucleosynthesis and the discovery of the cosmic microwave background in 1964. In Physical cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than those of H-1 (i The Big Bang model rests on two theoretical pillars: Albert Einstein's general relativity and the cosmological principle. The cosmological principle is an assumption invoked in Cosmology that when applied severely restricts the large variety of possible cosmological theories Cosmologists have recently established a precise model of the evolution of the universe, which includes cosmic inflation, dark energy and dark matter. &LambdaCDM or Lambda-CDM is an abbreviation for Lambda-Cold Dark Matter. In Physical cosmology, cosmic inflation is the idea that the nascent Universe passed through a phase of exponential expansion that In Physical cosmology, dark energy is a hypothetical exotic form of Energy that permeates all of space and tends to increase the rate of expansion of the universe In Physics and cosmology, dark matter is hypothetical Matter that does not interact with the electromagnetic force but whose presence can be inferred from
Applied physics
Applied physics is a general term for physics which is intended for a particular use. In Economics, utility is a measure of the relative satisfaction from or desirability of Consumption of various Goods and services. Applied is distinguished from pure by a subtle combination of factors such as the motivation and attitude of researchers and the nature of the relationship to the technology or science that may be affected by the work. [23] It usually differs from engineering in that an applied physicist may not be designing something in particular, but rather is using physics or conducting physics research with the aim of developing new technologies or solving a problem. Engineering is the Discipline and Profession of applying technical and scientific Knowledge and The approach is similar to that of applied mathematics. Applied mathematics is a branch of Mathematics that concerns itself with the mathematical techniques typically used in the application of mathematical knowledge to other domains Applied physicists can also be interested in the use of physics for scientific research. For instance, people working on accelerator physics might seek to build better particle detectors for research in theoretical physics. Accelerator physics deals with the problems of building and operating Particle accelerators The experiments conducted with particle accelerators are not regarded as part
Physics is used heavily in engineering. Engineering is the Discipline and Profession of applying technical and scientific Knowledge and For example, statics, a subfield of mechanics, is used in the building of bridges or other structures, while acoustics is used to design better concert halls. Statics is the branch of Mechanics concerned with the analysis of loads ( Force, torque/moment) on Physical systems in Static equilibrium Mechanics ( Greek) is the branch of Physics concerned with the behaviour of physical bodies when subjected to Forces or displacements A bridge is a Structure built to span a Gorge, Valley, Road, railroad track, River, Body of water Acoustics is the interdisciplinary science that deals with the study of Sound, Ultrasound and Infrasound (all mechanical waves in gases liquids and solids An understanding of physics is important to the design of realistic flight simulators, video game physics engines, and movies. A flight simulator is a system that tries to copy or simulate, the experience of flying an aircraft A physics engine is a Computer program that simulates Newtonian physics models using variables such as Mass, Velocity, Friction and
Physics Education
Physics education refers both to the methods currently used to teach physics, and to an area of pedagogical research that seeks to improve those methods. Physics education refers both to the methods currently used to teach Physics and to an area of pedagogical research that seeks to improve those methods Physics education refers both to the methods currently used to teach Physics and to an area of pedagogical research that seeks to improve those methods Historically, physics has been taught at the high school and university level primarily by the lecture method, together with laboratory exercises aimed at verifying concepts taught in the lectures.
References
- ^ R. P. Feynman, R. B. Leighton, M. Richard Phillips Feynman (ˈfaɪnmən May 11 1918 – February 15 1988 was an American Physicist known for the Path integral formulation of quantum Robert B Leighton ( September 10, 1919 &ndash March 9, 1997) was an American Sands (1963), The Feynman Lectures on Physics, ISBN 0-201-02116-1 Hard-cover. The Feynman Lectures on Physics by Richard Feynman, Robert Leighton, and Matthew Sands is perhaps Feynman's most accessible technical work p. 1-1 Feynman begins with the atomic hypothesis, as his most compact statement of all scientific knowledge: "If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations . This article focuses on the historical models of the atom For a history of the study of how atoms combine to form molecules see History of the molecule. . . , what statement would contain the most information in the fewest words? I believe it is . . . that all things are made up of atoms -- little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. . . . " vol. I p. I-2
- ^ James Clerk Maxwell (1876), Matter and Motion. James Clerk Maxwell (13 June 1831 &ndash 5 November 1879 was a Scottish mathematician and theoretical physicist. Notes and appendices by Joseph Larmor. Sir Joseph Larmor ( 11 July 1857 Magheragall, County Antrim, Northern Ireland – 19 May 1942 Holywood "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events". p. 1
- ^ "Give me matter and motion, and I will construct the universe. " --Rene Descartes (1596-1650)
- ^ Inquiring Minds
- ^ E. F. Taylor, J.A. Wheeler (2000), Exploring Black Holes: Introduction to General Relativity, ISBN 0-201-38423-X Hard-cover. John Archibald Wheeler ( July 9, 1911 &ndash April 13, 2008) was an eminent American Theoretical physicist. Back cover: "Spacetime tells matter how to move; mass tells spacetime how to curve. "
- ^ H. D. Young & R. A. Freedman, University Physics with Modern Physics: 11th Edition: International Edition (2004), Addison Wesley. Chapter 1, section 1. 1, page 2 has this to say: "Physics is an experimental science. Physicists observe the phenomena of nature and try to find patterns and principles that relate these phenomena. These patterns are called physical theories or, when they are well established and of broad use, physical laws or principles. "
- ^ Steve Holzner, Physics for Dummies (2006), Wiley. Chapter 1, page 7 says: "Physics is the study of your world and the world and universe around you. " See Amazon Online Reader: Physics For Dummies (For Dummies(Math & Science)), last viewed 24 Nov 2006.
- ^ Francis Bacon (1620), Novum Organum was critical in the development of scientific method. Francis Bacon 1st Viscount St Alban KC QC (22 January 1561 – 9 April 1626 was an English Philosopher, Statesman, and author The history of Scientific method is inseparable from the History of science itself
- ^ Evidence exists that the earliest civilizations dating back to beyond 3000BC, such as the Sumerians, Ancient Egyptians, and the Indus Valley Civilization, all had a predictive knowledge and a basic understanding of the motions of the Sun, Moon, and stars. Sumer ( Sumerian: sux-Latn [[Ki (earth ki]]-[[EN (cuneiform en]]-'''ĝir15''', Akkadian: Šumeru; possibly Biblical Shinar Ancient Egypt was an Ancient Civilization in eastern North Africa, concentrated along the lower reaches of the Nile River in what is now The Indus Valley Civilization (Mature period 2600&ndash1900 BCE abbreviated IVC, was an ancient Civilization that flourished in the Indus River basin
- ^ Change in velocity of light causes apparent changes in mass,dimension and time. Taylor, Edwin F. & Wheeler, John Archibald (1966), Spacetime Physics, San Francisco: W. John Archibald Wheeler ( July 9, 1911 &ndash April 13, 2008) was an eminent American Theoretical physicist. H. Freeman and Company, ISBN 0-7167-0336-X See, for example, The Relativistic Rocket, Problem #58, page 141, and its worked answer.
- ^ Einstein, Albert (November 25, 1915). Albert Einstein ( German: ˈalbɐt ˈaɪ̯nʃtaɪ̯n; English: ˈælbɝt ˈaɪnstaɪn (14 March 1879 – 18 April 1955 was a German -born theoretical Events 1034 - Máel Coluim mac Cináeda, King of Scots dies Donnchad, the Year 1915 ( MCMXV) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar (or a Common year "Die Feldgleichungen der Gravitation". Sitzungsberichte der Preussischen Akademie der Wissenschaften zu Berlin: 844-847.
- ^ Einstein, Albert (1916). "The Foundation of the General Theory of Relativity" (PDF). Annalen der Physik.
- ^ Perrot, Pierre (1998). A to Z of Thermodynamics. Oxford University Press. ISBN 0-19-856552-6.
- ^ Clark, John, O. E. (2004). The Essential Dictionary of Science. Barnes & Noble Books. ISBN 0-7607-4616-8.
- ^ Clausius, Ruldolf (1850). On the Motive Power of Heat, and on the Laws which can be deduced from it for the Theory of Heat. Poggendorff's Annalen der Physick, LXXIX (Dover Reprint). ISBN 0-486-59065-8.
- ^ Van Ness, H. C. (1969). Understanding Thermodynamics. Dover Publications, Inc. . ISBN 0-486-63277-6.
- ^ Dugdale, J. S. (1998). Entropy and its Physical Meaning. Taylor and Francis. ISBN 0-7484-0569-0.
- ^ Max Planck (1925), A Survey of Physical Theory derives his law of blackbody radiation in the notes on pp. 115-116, ISBN 0-486-67867-9
- ^ Feynman Lectures on Physics, vol I p. The Feynman Lectures on Physics by Richard Feynman, Robert Leighton, and Matthew Sands is perhaps Feynman's most accessible technical work 41-6, ISBN 0-201-02010-6
- ^ See, for example, the influence of Kant and Ritter on Oersted. Immanuel Kant (ɪmanuəl kant 22 April 1724 12 February 1804 was an 18th-century German Philosopher from the Prussian city of Königsberg Johann Wilhelm Ritter ( December 16, 1776 – January 23, 1810) was a German Chemist and Physicist.
- ^ Yet, universalism is encouraged in the culture of physics. For example, the World Wide Web, which was innovated at CERN by Tim Berners-Lee, was created in service to the computer infrastructure of CERN, and was/is intended for use by physicists worldwide. The World Wide Web (commonly shortened to the Web) is a system of interlinked Hypertext documents accessed via the Internet. The European Organization for Nuclear Research (Organisation Européenne pour la Recherche Nucléaire known as CERN Sir Timothy John Berners-Lee OM KBE FRS FREng FRSA (born 8 June 1955 is an English computer scientist who is credited The same might be said for arXiv.org
- ^ Division of Condensed Matter Physics Governance History. The arXiv ( pronounced " Archive " as if the "X" were the Greek letter Chi, χ is an Archive for electronic Retrieved on 2007-02-13. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1258 - Baghdad falls to the Mongols, and the Abbasid Caliphate is destroyed
- ^ Stanford Applied Physics Department Description
Further reading
- A large number of textbooks, popular books, and webpages about physics are available for further reading. This page lists sources for further reading about Physics. Webpages Nature Physics The Vega Science Trust includes hours of Freeview Science
- Important publications in physics
Organizations
- AIP.org is the website of the American Institute of Physics
- IOP.org is the website of the Institute of Physics
- APS.org is the website of the American Physical Society
- SPS National is the website of the American Society of Physics Students
- CAP.ca is the website of the Canadian Association of Physicists
- EPS.org is the website of the European Physical Society
Optics Book of Optics The American Institute of Physics (AIP is an international body representing Physicists and publishing physics related journals The Institute of Physics (IOP is the UK and Ireland 's main professional body for Physicists It was founded as the Physical Society The American Physical Society was founded in 1899 and is the World 's second largest organization of physicists behind the Deutsche Physikalische Gesellschaft. The Society of Physics Students ( SPS) is a professional association with international participation granting membership through college chapters with the The Canadian Association of Physicists (CAP is a Canadian lobby that focuses on creating awareness amongst Canadians and Canadian legislator of Physics The European Physical Society (EPS is a non-profit organization whose purpose is to promote physics and physicists in Europe
Dictionary
physics
-noun
- The branch of science concerned with the study of properties and interactions of space, time, matter and energy.
- Of or pertaining to the physical aspects of a phenomena or a system, especially those studied in physics.
-noun
- Plural form of physic.
-verb
- Third-person singular simple present indicative form of physic.
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