313 relations: Aberration of light, Academic Press, Accademia del Cimento, Addison-Wesley, Al-Biruni, Albert A. Michelson, Albert Einstein, American Journal of Physics, American Journal of Science, Ampere, Ancient Greece, Andromeda Galaxy, Angular frequency, Annalen der Physik, Annals of Physics, Annus Mirabilis papers, Apollo 8, Aristotelian physics, Aristotle, Astronomical unit, Astronomy & Astrophysics, Astrophysical jet, Atmosphere of Earth, Atomic nucleus, Attenuation coefficient, Barycentric Dynamical Time, BiblioBazaar, Book of Optics, Bose–Einstein condensate, Boulder, Colorado, Butterworth-Heinemann, Caesium, Cambridge University Press, Canis Major Overdensity, Capacitance, Capacitor, Carl Benjamin Boyer, Causality (physics), Celestial Mechanics and Dynamical Astronomy, Cengage, Central processing unit, Charged particle, Cherenkov radiation, Christiaan Huygens, Chronology of the universe, Classical physics, Coherence (physics), Complex number, Comptes rendus de l'Académie des Sciences, Computer, ..., CRC Press, Curve fitting, Diameter, Dielectric, Dispersion (optics), Doppler effect, Dover Publications, Early Islamic philosophy, Early modern period, Earth, Edward W. Morley, Einstein synchronisation, Electrical resistance and conductance, Electromagnetic field, Electromagnetic radiation, Electromagnetism, Emission theory (vision), Empedocles, Energy level, EPR paradox, Equator, Euclid, Euclidean vector, Expansion of the universe, Field (physics), Fizeau–Foucault apparatus, Florian Cajori, Foot (unit), French Academy of Sciences, Frequency, Front velocity, Galaxy formation and evolution, Galilean invariance, Galileo Galilei, Gamma-ray burst, General Conference on Weights and Measures, General relativity, Geometrized unit system, Geostationary orbit, Glass, Global Positioning System, Gram, Graphical projection, Gravitational constant, Gravitational wave, Group velocity, Gustav Kirchhoff, Hartman effect, Harvard University, Harvard University Press, Harvard–Smithsonian Center for Astrophysics, Hendrik Lorentz, Henri Poincaré, Hero of Alexandria, Hertz, Higgs mechanism, High-frequency trading, Hippolyte Fizeau, Hubble Ultra-Deep Field, Hubble volume, Hughes–Drever experiment, Ibn al-Haytham, Impedance of free space, Imperial units, Inertial frame of reference, Infinity, Integrated circuit, Interferometry, International Astronomical Union, International Bureau of Weights and Measures, International System of Units, Invariant mass, Io (moon), IOS Press, Isaac Beeckman, Isaac Newton, Isis (journal), Isotopes of caesium, Isotropy, James Bradley, James Clerk Maxwell, Johannes Kepler, John Walker (programmer), John Wiley & Sons, Journal des sçavans, Jupiter, Kilometres per hour, Kramers–Kronig relations, Laser, Léon Foucault, Length contraction, Leyden jar, Light, Light-second, Light-year, Lorentz covariance, Lorentz ether theory, Lorentz factor, Lorentz transformation, Louis Essen, Luminiferous aether, Lunar eclipse, Lunar Laser Ranging experiment, Macmillan Publishers, MacTutor History of Mathematics archive, Mars, Mass–energy equivalence, Massless particle, Mathematical Proceedings of the Cambridge Philosophical Society, Maxwell's equations, McGraw-Hill Education, Measurement uncertainty, Metre, Metre per second, Michelson–Morley experiment, Microsecond, Microwave, Microwave cavity, Microwave oven, Miles per hour, Milky Way, Millisecond, Minute, Minute and second of arc, Mission control center, Moon, Nanosecond, NASA, NASA Deep Space Network, National Institute of Standards and Technology, National Physical Laboratory (United Kingdom), Natural units, Nature (journal), Node (physics), Non-inertial reference frame, Normal mode, Observable universe, Ole Rømer, One-way speed of light, Optical cavity, Optical fiber, Optical properties of water and ice, Opticks, Optics Communications, Oscilloscope, Outer space, Oxford University Press, Paradox, Parsec, Particle physics, Paul Drude, Permeability (electromagnetism), Phase velocity, Philosophical Transactions of the Royal Society, Photon, Physical constant, Physical information, Physical Review, Physical Review Letters, Physics, Physics World, Pierre de Fermat, Planck constant, Planck length, Planck time, Planck units, Plane wave, Polarization (waves), Popular science, Preferred frame, Principle of relativity, Proca action, Proceedings of the Royal Society, Proceedings of the USSR Academy of Sciences, Propagation of light in non-inertial reference frames, Proper length, Proposed redefinition of SI base units, Proxima Centauri, Ptolemy, Quantum chromodynamics, Quantum electrodynamics, Quantum entanglement, Quantum gravity, Quantum mechanics, Quantum state, Quantum superposition, Quantum tunnelling, Quasar, Radar, Radar astronomy, Radian, Radio frequency, Radio galaxy, Radius, Rømer's determination of the speed of light, Refractive index, Relative permittivity, Relativity of simultaneity, René Descartes, Reproducibility, Resonator, Reviews of Modern Physics, Roger Bacon, Round-trip delay time, Rowland Institute for Science, Royal Society of Chemistry, Rubidium, Rudolf Kohlrausch, Scharnhorst effect, Second, Shock wave, Slow light, Snell's law, Solar System, Space probe, Space Telescope Science Institute, Spacetime, Special relativity, Speed of electricity, Speed of gravity, Speed of sound, Springer Science+Business Media, Standard Model, Statistical Science, Stellar evolution, Sun, Sunlight, Supercomputer, Superluminal motion, Symmetry (physics), Tachyonic antitelephone, Telecommunication, Terrell rotation, Tests of relativistic energy and momentum, The Astrophysical Journal, The New York Times, The Physics Teacher, The Road to Reality, Theory of relativity, Time dilation, Time of flight, Transparency and translucency, United States customary units, United States Naval Observatory, Universe, University of California, Riverside, University of St Andrews, University of Virginia, Vacuum, Vacuum permeability, Vacuum permittivity, Variable speed of light, Velocity factor, Vintage Books, Virtual particle, Visual perception, Vitello, W. 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The aberration of light (also referred to as astronomical aberration, stellar aberration, or velocity aberration) is an astronomical phenomenon which produces an apparent motion of celestial objects about their true positions, dependent on the velocity of the observer.
Academic Press is an academic book publisher.
The Accademia del Cimento (Academy of Experiment), an early scientific society, was founded in Florence in 1657 by students of Galileo, Giovanni Alfonso Borelli and Vincenzo Viviani and ceased to exist about a decade later.
Addison-Wesley is a publisher of textbooks and computer literature.
Abū Rayḥān Muḥammad ibn Aḥmad Al-Bīrūnī (Chorasmian/ابوریحان بیرونی Abū Rayḥān Bērōnī; New Persian: Abū Rayḥān Bīrūnī) (973–1050), known as Al-Biruni (البيروني) in English, was an IranianD.J. Boilot, "Al-Biruni (Beruni), Abu'l Rayhan Muhammad b. Ahmad", in Encyclopaedia of Islam (Leiden), New Ed., vol.1:1236–1238.
Albert Abraham Michelson FFRS HFRSE (December 19, 1852 – May 9, 1931) was an American physicist known for his work on measuring the speed of light and especially for the Michelson–Morley experiment.
Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).
The American Journal of Physics is a monthly, peer-reviewed scientific journal published by the American Association of Physics Teachers and the American Institute of Physics.
The American Journal of Science (AJS) is the United States of America's longest-running scientific journal, having been published continuously since its conception in 1818 by Professor Benjamin Silliman, who edited and financed it himself.
The ampere (symbol: A), often shortened to "amp",SI supports only the use of symbols and deprecates the use of abbreviations for units.
Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 13th–9th centuries BC to the end of antiquity (AD 600).
The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way.
In physics, angular frequency ω (also referred to by the terms angular speed, radial frequency, circular frequency, orbital frequency, radian frequency, and pulsatance) is a scalar measure of rotation rate.
Annalen der Physik (English: Annals of Physics) is one of the oldest scientific journals on physics and has been published since 1799.
Annals of Physics is a monthly peer-reviewed scientific journal covering all aspects of physics.
The Annus mirabilis papers (from Latin annus mīrābilis, "extraordinary year") are the papers of Albert Einstein published in the Annalen der Physik scientific journal in 1905.
Apollo 8, the second manned spaceflight mission in the United States Apollo space program, was launched on December 21, 1968, and became the first manned spacecraft to leave Earth orbit, reach the Earth's Moon, orbit it and return safely to Earth.
Aristotelian physics is a form of natural science described in the works of the Greek philosopher Aristotle (384–).
Aristotle (Ἀριστοτέλης Aristotélēs,; 384–322 BC) was an ancient Greek philosopher and scientist born in the city of Stagira, Chalkidiki, in the north of Classical Greece.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
Astronomy & Astrophysics is a peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics.
An astrophysical jet is an astronomical phenomenon where outflows of ionised matter are emitted as an extended beam along the axis of rotation.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.
Attenuation coefficient or narrow beam attenuation coefficient of the volume of a material characterizes how easily it can be penetrated by a beam of light, sound, particles, or other energy or matter.
Barycentric Dynamical Time (TDB, from the French Temps Dynamique Barycentrique) is a relativistic coordinate time scale, intended for astronomical use as a time standard to take account of time dilation when calculating orbits and astronomical ephemerides of planets, asteroids, comets and interplanetary spacecraft in the Solar System.
BiblioBazaar is, with Nabu Press, an imprint of the historical reprints publisher BiblioLife, which is based in Charleston, South Carolina and owned by BiblioLabs LLC.
The Book of Optics (Kitāb al-Manāẓir; Latin: De Aspectibus or Perspectiva; Italian: Deli Aspecti) is a seven-volume treatise on optics and other fields of study composed by the medieval Arab scholar Ibn al-Haytham, known in the West as Alhazen or Alhacen (965– c. 1040 AD).
A Bose–Einstein condensate (BEC) is a state of matter of a dilute gas of bosons cooled to temperatures very close to absolute zero.
Boulder is the home rule municipality that is the county seat and the most populous municipality of Boulder County, and the 11th most populous municipality in the U.S. state of Colorado.
Butterworth–Heinemann is a British publishing company specialized in professional information and learning materials for higher education and professional training, in printed and electronic forms.
Caesium (British spelling and IUPAC spelling) or cesium (American spelling) is a chemical element with symbol Cs and atomic number 55.
Cambridge University Press (CUP) is the publishing business of the University of Cambridge.
The Canis Major Dwarf Galaxy (CMa Dwarf) or Canis Major Overdensity (CMa Overdensity) is a disputed dwarf irregular galaxy in the Local Group, located in the same part of the sky as the constellation Canis Major.
Capacitance is the ratio of the change in an electric charge in a system to the corresponding change in its electric potential.
A capacitor is a passive two-terminal electrical component that stores potential energy in an electric field.
Carl Benjamin Boyer (November 3, 1906 – April 26, 1976) was an American historian of sciences, and especially mathematics.
Causality is the relationship between causes and effects.
Celestial Mechanics and Dynamical Astronomy is a scientific journal covering the fields of astronomy and astrophysics.
Cengage is an educational content, technology, and services company for the higher education, K-12, professional, and library markets worldwide.
A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified by the instructions.
In physics, a charged particle is a particle with an electric charge.
Cherenkov radiation (sometimes spelled "Cerenkov") is electromagnetic radiation emitted when a charged particle (such as an electron) passes through a dielectric medium at a speed greater than the phase velocity of light in that medium.
Christiaan Huygens (Hugenius; 14 April 1629 – 8 July 1695) was a Dutch physicist, mathematician, astronomer and inventor, who is widely regarded as one of the greatest scientists of all time and a major figure in the scientific revolution.
The chronology of the universe describes the history and future of the universe according to Big Bang cosmology.
Classical physics refers to theories of physics that predate modern, more complete, or more widely applicable theories.
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform.
A complex number is a number that can be expressed in the form, where and are real numbers, and is a solution of the equation.
Comptes rendus de l'Académie des Sciences (English: Proceedings of the Academy of sciences), or simply Comptes rendus, is a French scientific journal which has been published since 1666.
A computer is a device that can be instructed to carry out sequences of arithmetic or logical operations automatically via computer programming.
The CRC Press, LLC is a publishing group based in the United States that specializes in producing technical books.
Curve fitting is the process of constructing a curve, or mathematical function, that has the best fit to a series of data points, possibly subject to constraints.
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle.
A dielectric (or dielectric material) is an electrical insulator that can be polarized by an applied electric field.
In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency.
The Doppler effect (or the Doppler shift) is the change in frequency or wavelength of a wave in relation to observer who is moving relative to the wave source.
Dover Publications, also known as Dover Books, is an American book publisher founded in 1941 by Hayward Cirker and his wife, Blanche.
Early Islamic philosophy or classical Islamic philosophy is a period of intense philosophical development beginning in the 2nd century AH of the Islamic calendar (early 9th century CE) and lasting until the 6th century AH (late 12th century CE).
The early modern period of modern history follows the late Middle Ages of the post-classical era.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Edward Williams Morley (January 29, 1838 – February 24, 1923) was an American scientist famous for his extremely precise and accurate measurement of the atomic weight of oxygen, and for the Michelson–Morley experiment.
Einstein synchronisation (or Poincaré–Einstein synchronisation) is a convention for synchronising clocks at different places by means of signal exchanges.
The electrical resistance of an electrical conductor is a measure of the difficulty to pass an electric current through that conductor.
An electromagnetic field (also EMF or EM field) is a physical field produced by electrically charged objects.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles.
Emission theory or extramission theory (variants: extromission, extromittism) is the proposal that visual perception is accomplished by eye beams emitted by the eyes.
Empedocles (Ἐμπεδοκλῆς, Empedoklēs) was a Greek pre-Socratic philosopher and a citizen of Akragas, a Greek city in Sicily.
A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy.
The Einstein–Podolsky–Rosen paradox or the EPR paradox of 1935 is a thought experiment in quantum mechanics with which Albert Einstein and his colleagues Boris Podolsky and Nathan Rosen (EPR) claimed to demonstrate that the wave function does not provide a complete description of physical reality, and hence that the Copenhagen interpretation is unsatisfactory; resolutions of the paradox have important implications for the interpretation of quantum mechanics.
An equator of a rotating spheroid (such as a planet) is its zeroth circle of latitude (parallel).
Euclid (Εὐκλείδης Eukleidēs; fl. 300 BC), sometimes given the name Euclid of Alexandria to distinguish him from Euclides of Megara, was a Greek mathematician, often referred to as the "founder of geometry" or the "father of geometry".
In mathematics, physics, and engineering, a Euclidean vector (sometimes called a geometric or spatial vector, or—as here—simply a vector) is a geometric object that has magnitude (or length) and direction.
The expansion of the universe is the increase of the distance between two distant parts of the universe with time.
In physics, a field is a physical quantity, represented by a number or tensor, that has a value for each point in space and time.
Fizeau–Foucault apparatus is a term sometimes used to refer to two types of instrument historically used to measure the speed of light.
Florian Cajori (February 28, 1859 – August 14 or 15, 1930) was a Swiss-American historian of mathematics.
The foot (feet; abbreviation: ft; symbol: ′, the prime symbol) is a unit of length in the imperial and US customary systems of measurement.
The French Academy of Sciences (French: Académie des sciences) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research.
Frequency is the number of occurrences of a repeating event per unit of time.
In physics, front velocity is the speed at which the first rise of a pulse above zero moves forward.
The study of galaxy formation and evolution is concerned with the processes that formed a heterogeneous universe from a homogeneous beginning, the formation of the first galaxies, the way galaxies change over time, and the processes that have generated the variety of structures observed in nearby galaxies.
Galilean invariance or Galilean relativity states that the laws of motion are the same in all inertial frames.
Galileo Galilei (15 February 1564Drake (1978, p. 1). The date of Galileo's birth is given according to the Julian calendar, which was then in force throughout Christendom. In 1582 it was replaced in Italy and several other Catholic countries with the Gregorian calendar. Unless otherwise indicated, dates in this article are given according to the Gregorian calendar. – 8 January 1642) was an Italian polymath.
In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic explosions that have been observed in distant galaxies.
The General Conference on Weights and Measures (Conférence générale des poids et mesures – CGPM) is the supreme authority of the International Bureau of Weights and Measures (Bureau international des poids et mesures – BIPM), the inter-governmental organization established in 1875 under the terms of the Metre Convention (Convention du Mètre) through which Member States act together on matters related to measurement science and measurement standards.
General relativity (GR, also known as the general theory of relativity or GTR) is the geometric theory of gravitation published by Albert Einstein in 1915 and the current description of gravitation in modern physics.
A geometrized unit system or geometric unit system is a system of natural units in which the base physical units are chosen so that the speed of light in vacuum, c, and the gravitational constant, G, are set equal to unity.
A geostationary orbit, often referred to as a geosynchronous equatorial orbit (GEO), is a circular geosynchronous orbit above Earth's equator and following the direction of Earth's rotation.
Glass is a non-crystalline amorphous solid that is often transparent and has widespread practical, technological, and decorative usage in, for example, window panes, tableware, and optoelectronics.
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Air Force.
The gram (alternative spelling: gramme; SI unit symbol: g) (Latin gramma, from Greek γράμμα, grámma) is a metric system unit of mass.
Graphical projection is a protocol, used in technical drawing, by which an image of a three-dimensional object is projected onto a planar surface without the aid of numerical calculation.
The gravitational constant (also known as the "universal gravitational constant", the "Newtonian constant of gravitation", or the "Cavendish gravitational constant"), denoted by the letter, is an empirical physical constant involved in the calculation of gravitational effects in Sir Isaac Newton's law of universal gravitation and in Albert Einstein's general theory of relativity.
Gravitational waves are the disturbance in the fabric ("curvature") of spacetime generated by accelerated masses and propagate as waves outward from their source at the speed of light.
The group velocity of a wave is the velocity with which the overall shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space.
Gustav Robert Kirchhoff (12 March 1824 – 17 October 1887) was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects.
The delay time for a quantum tunneling particle is independent of the thickness of the opaque barrier.
Harvard University is a private Ivy League research university in Cambridge, Massachusetts.
Harvard University Press (HUP) is a publishing house established on January 13, 1913, as a division of Harvard University, and focused on academic publishing.
The Harvard–Smithsonian Center for Astrophysics (CfA) is a research institute which carries out a broad program of research in astronomy, astrophysics, earth and space sciences, and science education.
Hendrik Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect.
Jules Henri Poincaré (29 April 1854 – 17 July 1912) was a French mathematician, theoretical physicist, engineer, and philosopher of science.
Hero of Alexandria (ἭρωνGenitive: Ἥρωνος., Heron ho Alexandreus; also known as Heron of Alexandria; c. 10 AD – c. 70 AD) was a mathematician and engineer who was active in his native city of Alexandria, Roman Egypt.
The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.
In the Standard Model of particle physics, the Higgs mechanism is essential to explain the generation mechanism of the property "mass" for gauge bosons.
In financial markets, high-frequency trading (HFT) is a type of algorithmic trading characterized by high speeds, high turnover rates, and high order-to-trade ratios that leverages high-frequency financial data and electronic trading tools.
Armand Hippolyte Louis Fizeau FRS FRSE MIF (23 September 181918 September 1896) was a French physicist, best known for measuring the speed of light in the namesake Fizeau experiment.
The Hubble Ultra-Deep Field (HUDF) is an image of a small region of space in the constellation Fornax, containing an estimated 10,000 galaxies.
In cosmology, a Hubble volume or Hubble sphere is a spherical region of the observable universe surrounding an observer beyond which objects recede from that observer at a rate greater than the speed of light due to the expansion of the Universe.
Hughes–Drever experiments (also clock comparison-, clock anisotropy-, mass isotropy-, or energy isotropy experiments) are spectroscopic tests of the isotropy of mass and space.
Hasan Ibn al-Haytham (Latinized Alhazen; full name أبو علي، الحسن بن الحسن بن الهيثم) was an Arab mathematician, astronomer, and physicist of the Islamic Golden Age.
The impedance of free space,, is a physical constant relating the magnitudes of the electric and magnetic fields of electromagnetic radiation travelling through free space.
The system of imperial units or the imperial system (also known as British Imperial or Exchequer Standards of 1825) is the system of units first defined in the British Weights and Measures Act of 1824, which was later refined and reduced.
An inertial frame of reference in classical physics and special relativity is a frame of reference in which a body with zero net force acting upon it is not accelerating; that is, such a body is at rest or it is moving at a constant speed in a straight line.
Infinity (symbol) is a concept describing something without any bound or larger than any natural number.
An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon.
Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information.
The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.
The International Bureau of Weights and Measures (Bureau international des poids et mesures) is an intergovernmental organization established by the Metre Convention, through which Member States act together on matters related to measurement science and measurement standards.
The International System of Units (SI, abbreviated from the French Système international (d'unités)) is the modern form of the metric system, and is the most widely used system of measurement.
The invariant mass, rest mass, intrinsic mass, proper mass, or in the case of bound systems simply mass, is the portion of the total mass of an object or system of objects that is independent of the overall motion of the system.
Io (Jupiter I) is the innermost of the four Galilean moons of the planet Jupiter.
IOS Press is a publishing house headquartered in Amsterdam, specialising in the publication of journals and books related to fields of scientific, technical, and medical research.
Isaac Beeckman (10 December 1588 – 19 May 1637) was a Dutch philosopher and scientist, who, through his studies and contact with leading natural philosophers, may have "virtually given birth to modern atomism".
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, astronomer, theologian, author and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time, and a key figure in the scientific revolution.
Isis is a quarterly peer-reviewed academic journal published by the University of Chicago Press.
Caesium (55Cs; or cesium) has 40 known isotopes, making it, along with barium and mercury, the element with the most isotopes.
Isotropy is uniformity in all orientations; it is derived from the Greek isos (ἴσος, "equal") and tropos (τρόπος, "way").
James Bradley FRS (March 1693 – 13 July 1762) was an English astronomer and priest and served as Astronomer Royal from 1742, succeeding Edmond Halley.
James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish scientist in the field of mathematical physics.
Johannes Kepler (December 27, 1571 – November 15, 1630) was a German mathematician, astronomer, and astrologer.
John Walker is a computer programmer, author and co-founder of the computer-aided design software company Autodesk.
John Wiley & Sons, Inc., also referred to as Wiley, is a global publishing company that specializes in academic publishing.
The Journal des sçavans (later renamed Journal des savants), established by Denis de Sallo, was the earliest academic journal published in Europe.
Jupiter is the fifth planet from the Sun and the largest in the Solar System.
The kilometre per hour (American English: kilometer per hour) is a unit of speed, expressing the number of kilometres travelled in one hour.
The Kramers–Kronig relations are bidirectional mathematical relations, connecting the real and imaginary parts of any complex function that is analytic in the upper half-plane.
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.
Jean Bernard Léon Foucault (18 September 1819 – 11 February 1868) was a French physicist best known for his demonstration of the Foucault pendulum, a device demonstrating the effect of the Earth's rotation.
Length contraction is the phenomenon that a moving object's length is measured to be shorter than its proper length, which is the length as measured in the object's own rest frame.
A Leyden jar (or Leiden jar) stores a high-voltage electric charge (from an external source) between electrical conductors on the inside and outside of a glass jar.
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.
The light-second is a unit of length useful in astronomy, telecommunications and relativistic physics.
The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.
In relativistic physics, Lorentz symmetry, named for Hendrik Lorentz, is an equivalence of observation or observational symmetry due to special relativity implying that the laws of physics stay the same for all observers that are moving with respect to one another within an inertial frame.
What is now often called Lorentz ether theory (LET) has its roots in Hendrik Lorentz's "theory of electrons", which was the final point in the development of the classical aether theories at the end of the 19th and at the beginning of the 20th century.
The Lorentz factor or Lorentz term is the factor by which time, length, and relativistic mass change for an object while that object is moving.
In physics, the Lorentz transformations (or transformation) are coordinate transformations between two coordinate frames that move at constant velocity relative to each other.
Louis Essen FRS O.B.E. (6 September 1908 – 24 August 1997) was an English physicist whose most notable achievements were in the precise measurement of time and the determination of the speed of light.
In the late 19th century, luminiferous aether or ether ("luminiferous", meaning "light-bearing"), was the postulated medium for the propagation of light.
A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow.
The ongoing Lunar Laser Ranging experiment measures the distance between Earth and the Moon using laser ranging.
Macmillan Publishers Ltd (occasionally known as the Macmillan Group) is an international publishing company owned by Holtzbrinck Publishing Group.
The MacTutor History of Mathematics archive is a website maintained by John J. O'Connor and Edmund F. Robertson and hosted by the University of St Andrews in Scotland.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
In physics, mass–energy equivalence states that anything having mass has an equivalent amount of energy and vice versa, with these fundamental quantities directly relating to one another by Albert Einstein's famous formula: E.
In particle physics, a massless particle is an elementary particle whose invariant mass is zero.
Mathematical Proceedings of the Cambridge Philosophical Society is a mathematical journal published by Cambridge University Press for the Cambridge Philosophical Society.
Maxwell's equations are a set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits.
McGraw-Hill Education (MHE) is a learning science company and one of the "big three" educational publishers that provides customized educational content, software, and services for pre-K through postgraduate education.
In metrology, measurement uncertainty is a non-negative parameter characterizing the dispersion of the values attributed to a measured quantity.
The metre (British spelling and BIPM spelling) or meter (American spelling) (from the French unit mètre, from the Greek noun μέτρον, "measure") is the base unit of length in some metric systems, including the International System of Units (SI).
Metre per second (American English: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds.
The Michelson–Morley experiment was performed between April and July, 1887 by Albert A. Michelson and Edward W. Morley at what is now Case Western Reserve University in Cleveland, Ohio, and published in November of the same year.
A microsecond is an SI unit of time equal to one millionth (0.000001 or 10−6 or 1/1,000,000) of a second.
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; with frequencies between and.
A microwave cavity or radio frequency (RF) cavity is a special type of resonator, consisting of a closed (or largely closed) metal structure that confines electromagnetic fields in the microwave region of the spectrum.
A microwave oven (also commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range.
Miles per hour (abbreviated mph, MPH or mi/h) is an imperial and United States customary unit of speed expressing the number of statute miles covered in one hour.
The Milky Way is the galaxy that contains our Solar System.
A millisecond (from milli- and second; symbol: ms) is a thousandth (0.001 or 10−3 or 1/1000) of a second.
The minute is a unit of time or angle.
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.
A mission control center (MCC, sometimes called a flight control center or operations center) is a facility that manages space flights, usually from the point of launch until landing or the end of the mission.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
A nanosecond (ns) is an SI unit of time equal to one thousand-millionth of a second (or one billionth of a second), that is, 1/1,000,000,000 of a second, or 10 seconds.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
The NASA Deep Space Network (DSN) is a worldwide network of US spacecraft communication facilities, located in the United States (California), Spain (Madrid), and Australia (Canberra), that supports NASA's interplanetary spacecraft missions.
The National Institute of Standards and Technology (NIST) is one of the oldest physical science laboratories in the United States.
The National Physical Laboratory (NPL) is the national measurement standards laboratory for the United Kingdom, based at Bushy Park in Teddington, London, England.
In physics, natural units are physical units of measurement based only on universal physical constants.
Nature is a British multidisciplinary scientific journal, first published on 4 November 1869.
A node is a point along a standing wave where the wave has minimum amplitude.
A non-inertial reference frame is a frame of reference that is undergoing acceleration with respect to an inertial frame.
A normal mode of an oscillating system is a pattern of motion in which all parts of the system move sinusoidally with the same frequency and with a fixed phase relation.
The observable universe is a spherical region of the Universe comprising all matter that can be observed from Earth at the present time, because electromagnetic radiation from these objects has had time to reach Earth since the beginning of the cosmological expansion.
Ole Christensen Rømer (25 September 1644 – 19 September 1710) was a Danish astronomer who in 1676 made the first quantitative measurements of the speed of light.
When using the term 'the speed of light' it is sometimes necessary to make the distinction between its one-way speed and its two-way speed.
An optical cavity, resonating cavity or optical resonator is an arrangement of mirrors that forms a standing wave cavity resonator for light waves.
An optical fiber or optical fibre is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
The refractive index of water at 20 °C is 1.3330.
Opticks: or, A Treatise of the Reflexions, Refractions, Inflexions and Colours of Light is a book by English natural philosopher Isaac Newton that was published in English in 1704.
Optics Communications is a peer-reviewed rapid-publication scientific journal published by Elsevier.
An oscilloscope, previously called an oscillograph, and informally known as a scope or o-scope, CRO (for cathode-ray oscilloscope), or DSO (for the more modern digital storage oscilloscope), is a type of electronic test instrument that allows observation of varying signal voltages, usually as a two-dimensional plot of one or more signals as a function of time.
Outer space, or just space, is the expanse that exists beyond the Earth and between celestial bodies.
Oxford University Press (OUP) is the largest university press in the world, and the second oldest after Cambridge University Press.
A paradox is a statement that, despite apparently sound reasoning from true premises, leads to an apparently self-contradictory or logically unacceptable conclusion.
The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System.
Particle physics (also high energy physics) is the branch of physics that studies the nature of the particles that constitute matter and radiation.
Paul Karl Ludwig Drude (12 July 1863 – 5 July 1906) was a German physicist specializing in optics.
In electromagnetism, permeability is the measure of the ability of a material to support the formation of a magnetic field within itself.
The phase velocity of a wave is the rate at which the phase of the wave propagates in space.
Philosophical Transactions, titled Philosophical Transactions of the Royal Society (often abbreviated as Phil. Trans.) from 1776, is a scientific journal published by the Royal Society.
The photon is a type of elementary particle, the quantum of the electromagnetic field including electromagnetic radiation such as light, and the force carrier for the electromagnetic force (even when static via virtual particles).
A physical constant, sometimes fundamental physical constant or universal constant, is a physical quantity that is generally believed to be both universal in nature and have constant value in time.
In physics, physical information refers generally to the information that is contained in a physical system.
Physical Review is an American peer-reviewed scientific journal established in 1893 by Edward Nichols.
Physical Review Letters (PRL), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society.
Physics (from knowledge of nature, from φύσις phýsis "nature") is the natural science that studies matterAt the start of The Feynman Lectures on Physics, Richard Feynman offers the atomic hypothesis as the single most prolific scientific concept: "If, in some cataclysm, all scientific knowledge were to be destroyed one sentence 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..." and its motion and behavior through space and time and that studies the related entities of energy and force."Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves."Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physics. (...) You will come to see physics as a towering achievement of the human intellect in its quest to understand our world and ourselves."Physics is an experimental science. Physicists observe the phenomena of nature and try to find patterns that relate these phenomena.""Physics is the study of your world and the world and universe around you." Physics is one of the oldest academic disciplines and, through its inclusion of astronomy, perhaps the oldest. Over the last two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the scientific revolution in the 17th century, these natural sciences emerged as unique research endeavors in their own right. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in academic disciplines such as mathematics and philosophy. Advances in physics often enable advances in new technologies. For example, advances in the understanding of electromagnetism and nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.
Physics World is the membership magazine of the Institute of Physics, one of the largest physical societies in the world.
Pierre de Fermat (Between 31 October and 6 December 1607 – 12 January 1665) was a French lawyer at the Parlement of Toulouse, France, and a mathematician who is given credit for early developments that led to infinitesimal calculus, including his technique of adequality.
The Planck constant (denoted, also called Planck's constant) is a physical constant that is the quantum of action, central in quantum mechanics.
In physics, the Planck length, denoted, is a unit of length, equal to metres.
In quantum mechanics, the Planck time is the unit of time in the system of natural units known as Planck units.
In particle physics and physical cosmology, Planck units are a set of units of measurement defined exclusively in terms of five universal physical constants, in such a manner that these five physical constants take on the numerical value of 1 when expressed in terms of these units.
In the physics of wave propagation, a plane wave (also spelled planewave) is a wave whose wavefronts (surfaces of constant phase) are infinite parallel planes.
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.
Popular science (also called pop-science or popsci) is an interpretation of science intended for a general audience.
In theoretical physics, a preferred or privileged frame is usually a special hypothetical frame of reference in which the laws of physics might appear to be identifiably different (simpler) from those in other frames.
In physics, the principle of relativity is the requirement that the equations describing the laws of physics have the same form in all admissible frames of reference.
In physics, specifically field theory and particle physics, the Proca action describes a massive spin-1 field of mass m in Minkowski spacetime.
Proceedings of the Royal Society is the parent title of two scientific journals published by the Royal Society.
The Proceedings of the USSR Academy of Sciences (Доклады Академии Наук СССР, Doklady Akademii Nauk SSSR (DAN SSSR), Comptes Rendus de l'Académie des Sciences de l'URSS) was a Soviet journal that was dedicated to publishing original, academic research papers in physics, mathematics, chemistry, geology, and biology.
The description of motion in relativity requires more than one concept of speed.
Proper length or rest length refers to the length of an object in the object's rest frame.
The International Committee for Weights and Measures (CIPM) has proposed revised definitions of the SI base units, for consideration at the 26th General Conference on Weights and Measures (CGPM).
Proxima Centauri, or Alpha Centauri C, is a red dwarf, a small low-mass star, about from the Sun in the constellation of Centaurus.
Claudius Ptolemy (Κλαύδιος Πτολεμαῖος, Klaúdios Ptolemaîos; Claudius Ptolemaeus) was a Greco-Roman mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology.
In theoretical physics, quantum chromodynamics (QCD) is the theory of the strong interaction between quarks and gluons, the fundamental particles that make up composite hadrons such as the proton, neutron and pion.
In particle physics, quantum electrodynamics (QED) is the relativistic quantum field theory of electrodynamics.
Quantum entanglement is a physical phenomenon which occurs when pairs or groups of particles are generated, interact, or share spatial proximity in ways such that the quantum state of each particle cannot be described independently of the state of the other(s), even when the particles are separated by a large distance—instead, a quantum state must be described for the system as a whole.
Quantum gravity (QG) is a field of theoretical physics that seeks to describe gravity according to the principles of quantum mechanics, and where quantum effects cannot be ignored, such as near compact astrophysical objects where the effects of gravity are strong.
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
In quantum physics, quantum state refers to the state of an isolated quantum system.
Quantum superposition is a fundamental principle of quantum mechanics.
Quantum tunnelling or tunneling (see spelling differences) is the quantum mechanical phenomenon where a particle tunnels through a barrier that it classically cannot surmount.
A quasar (also known as a QSO or quasi-stellar object) is an extremely luminous active galactic nucleus (AGN).
Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects.
Radar astronomy is a technique of observing nearby astronomical objects by reflecting microwaves off target objects and analyzing the reflections.
The radian (SI symbol rad) is the SI unit for measuring angles, and is the standard unit of angular measure used in many areas of mathematics.
Radio frequency (RF) refers to oscillatory change in voltage or current in a circuit, waveguide or transmission line in the range extending from around twenty thousand times per second to around three hundred billion times per second, roughly between the upper limit of audio and the lower limit of infrared.
Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths, with luminosities up to 1039 W between 10 MHz and 100 GHz.
In classical geometry, a radius of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length.
Rømer's determination of the speed of light was the demonstration in 1676 that light has a finite speed, and so does not travel instantaneously.
In optics, the refractive index or index of refraction of a material is a dimensionless number that describes how light propagates through that medium.
The relative permittivity of a material is its (absolute) permittivity expressed as a ratio relative to the permittivity of vacuum.
In physics, the relativity of simultaneity is the concept that distant simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame.
René Descartes (Latinized: Renatus Cartesius; adjectival form: "Cartesian"; 31 March 1596 – 11 February 1650) was a French philosopher, mathematician, and scientist.
Reproducibility is the closeness of the agreement between the results of measurements of the same measurand carried out under changed conditions of measurement.
A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others.
Reviews of Modern Physics is a quarterly peer-reviewed scientific journal published by the American Physical Society.
Roger Bacon (Rogerus or Rogerius Baconus, Baconis, also Rogerus), also known by the scholastic accolade Doctor, was an English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empiricism.
In telecommunications, the round-trip delay time (RTD) or round-trip time (RTT) is the length of time it takes for a signal to be sent plus the length of time it takes for an acknowledgement of that signal to be received.
The Rowland Institute for Science was founded by Edwin H. Land, founder of Polaroid Corporation, as a nonprofit, privately-endowed basic research organization in 1980.
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemical sciences".
Rubidium is a chemical element with symbol Rb and atomic number 37.
Rudolf Hermann Arndt Kohlrausch (November 6, 1809 in Göttingen – March 8, 1858 in Erlangen) was a German physicist.
The Scharnhorst effect is a hypothetical phenomenon in which light signals travel slightly faster than ''c'' between two closely spaced conducting plates.
The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.
In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance.
Slow light is the propagation of an optical pulse or other modulation of an optical carrier at a very low group velocity.
Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.
The Solar SystemCapitalization of the name varies.
A space probe is a robotic spacecraft that does not orbit the Earth, but, instead, explores further into outer space.
The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST; in orbit since 1990) and for the James Webb Space Telescope (JWST; scheduled to be launched in March 2021).
In physics, spacetime is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum.
In physics, special relativity (SR, also known as the special theory of relativity or STR) is the generally accepted and experimentally well-confirmed physical theory regarding the relationship between space and time.
The word electricity refers generally to the movement of electrons (or other charge carriers) through a conductor in the presence of potential and an electric field.
In classical theories of gravitation, the changes in a gravitational field propagate.
The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium.
Springer Science+Business Media or Springer, part of Springer Nature since 2015, is a global publishing company that publishes books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing.
The Standard Model of particle physics is the theory describing three of the four known fundamental forces (the electromagnetic, weak, and strong interactions, and not including the gravitational force) in the universe, as well as classifying all known elementary particles.
Statistical Science is a review journal published by the Institute of Mathematical Statistics.
Stellar evolution is the process by which a star changes over the course of time.
The Sun is the star at the center of the Solar System.
Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light.
A supercomputer is a computer with a high level of performance compared to a general-purpose computer.
In astronomy, superluminal motion is the apparently faster-than-light motion seen in some radio galaxies, BL Lac objects, quasars and recently also in some galactic sources called microquasars.
In physics, a symmetry of a physical system is a physical or mathematical feature of the system (observed or intrinsic) that is preserved or remains unchanged under some transformation.
A tachyonic antitelephone is a hypothetical device in theoretical physics that could be used to send signals into one's own past.
Telecommunication is the transmission of signs, signals, messages, words, writings, images and sounds or information of any nature by wire, radio, optical or other electromagnetic systems.
Terrell rotation or Terrell effect is the visual distortion that a passing object would appear to undergo, according to the special theory of relativity if it were travelling a significant fraction of the speed of light.
Tests of relativistic energy and momentum are aimed at measuring the relativistic expressions for energy, momentum, and mass.
The Astrophysical Journal, often abbreviated ApJ (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler.
The New York Times (sometimes abbreviated as The NYT or The Times) is an American newspaper based in New York City with worldwide influence and readership.
The Physics Teacher is a peer-reviewed academic journal published by AIP Publishing on behalf of the American Association of Physics Teachers covering the history and philosophy of physics, applied physics, physics education (curriculum developments, pedagogy, instructional lab equipment, etc.), and book reviews.
The Road to Reality: A Complete Guide to the Laws of the Universe is a book on modern physics by the British mathematical physicist Roger Penrose, published in 2004.
The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity.
According to the theory of relativity, time dilation is a difference in the elapsed time measured by two observers, either due to a velocity difference relative to each other, or by being differently situated relative to a gravitational field.
Time of flight (TOF) is a property of an object, particle or acoustic, electromagnetic or other wave.
In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without being scattered.
United States customary units are a system of measurements commonly used in the United States.
The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States, with a primary mission to produce Positioning, Navigation and Timing (PNT) for the United States Navy and the United States Department of Defense.
The Universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy.
The University of California, Riverside (UCR or UC Riverside), is a public research university and one of the 10 general campuses of the University of California system.
The University of St Andrews (informally known as St Andrews University or simply St Andrews; abbreviated as St And, from the Latin Sancti Andreae, in post-nominals) is a British public research university in St Andrews, Fife, Scotland.
The University of Virginia (U.Va. or UVA), frequently referred to simply as Virginia, is a public research university and the flagship for the Commonwealth of Virginia.
Vacuum is space devoid of matter.
The physical constant μ0, (pronounced "mu naught" or "mu zero"), commonly called the vacuum permeability, permeability of free space, permeability of vacuum, or magnetic constant, is an ideal, (baseline) physical constant, which is the value of magnetic permeability in a classical vacuum.
The physical constant (pronounced as "epsilon nought"), commonly called the vacuum permittivity, permittivity of free space or electric constant, is an ideal, (baseline) physical constant, which is the value of the absolute dielectric permittivity of classical vacuum.
A variable speed of light (VSL) is a feature of a family of hypotheses stating that the speed of light in vacuum, usually denoted by c, may in some way not be constant, e.g. varying in space or time, or depending on frequency.
The velocity factor (VF), also called wave propagation speed or velocity of propagation (VoP or of a transmission medium is the ratio of the speed at which a wavefront (of an electromagnetic signal, a radio signal, a light pulse in an optical fibre or a change of the electrical voltage on a copper wire) passes through the medium, to the speed of light in a vacuum.
Vintage Books is a publishing imprint established in 1954 by Alfred A. Knopf.
In physics, a virtual particle is a transient fluctuation that exhibits some of the characteristics of an ordinary particle, but whose existence is limited by the uncertainty principle.
Visual perception is the ability to interpret the surrounding environment using light in the visible spectrum reflected by the objects in the environment.
Witelo (also Erazmus Ciołek Witelo; Witelon; Vitellio; Vitello; Vitello Thuringopolonis; Vitulon; Erazm Ciołek); born ca.
A warp drive is a fictitious faster-than-light (FTL) spacecraft propulsion system in many science fiction works, most notably Star Trek.
In physics, interference is a phenomenon in which two waves superpose to form a resultant wave of greater, lower, or the same amplitude.
Wilhelm Eduard Weber (24 October 1804 – 23 June 1891) was a German physicist and, together with Carl Friedrich Gauss, inventor of the first electromagnetic telegraph.
World Scientific Publishing is an academic publisher of scientific, technical, and medical books and journals headquartered in Singapore.
X-rays make up X-radiation, a form of electromagnetic radiation.
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