Was ist visa electron

was ist visa electron

Damit ist die Karte bei angezeigtem „Visa electron“-Logo an Terminals im Handel oder zum Bezahlen im Internet einsetzbar. Visa electron wird sowohl als. Kennzeichnend für die Visa Electron ist eine fehlende Hochprägung der Kartendaten, sodass die Karte auch nur an sogenannten POS-Kassen (Point of Sale). Mit einer VISA Electron Prepaid-Kreditkarte können Sie im Rahmen Ihres verfügbaren Guthabens weltweit an allen mit dem VISA oder VISA Electron- Symbol.

Visa Electron is a debit card product that uses the Visa payment system. It is offered by issuing banks in every country with the exception of Canada , Australia , Republic of Ireland and the United States.

Visa Debit cards, on the other hand, typically allow transfers exceeding available funds up to a certain limit. For that reason, Visa Electron cards are more commonly issued to younger customers or customers that have poor credit.

In addition to point of sale debit payments, the card also allows the holder to withdraw cash from automated teller machines ATMs using the Plus interbank network.

In , Banque Misr began offering the cards. In the United Kingdom the card is not as widely accepted as the Visa Debit card.

Many banks have migrated away from Visa Electron and instead issue Visa Debit cards and Visa Electron issuance is declining. A Visa Electron logo, usually on the bottom right.

Most Visa Electron cards do not have the dove hologram as on Visa credit and debit cards, but a few banks do include it. The card number and validity as well as cardholder name are printed rather than embossed , thus the card cannot be used in a card imprinter — for card-present transactions the card requires a reader of magnetic stripe cards , EMV reader or contactless payment terminal.

From Wikipedia, the free encyclopedia. Not to be confused with Visa Debit. This article needs additional citations for verification.

Please help improve this article by adding citations to reliable sources. The Big Bang theory is the most widely accepted scientific theory to explain the early stages in the evolution of the Universe.

These photons were sufficiently energetic that they could react with each other to form pairs of electrons and positrons.

Likewise, positron-electron pairs annihilated each other and emitted energetic photons:. An equilibrium between electrons, positrons and photons was maintained during this phase of the evolution of the Universe.

After 15 seconds had passed, however, the temperature of the universe dropped below the threshold where electron-positron formation could occur.

Most of the surviving electrons and positrons annihilated each other, releasing gamma radiation that briefly reheated the universe.

For reasons that remain uncertain, during the annihilation process there was an excess in the number of particles over antiparticles. Hence, about one electron for every billion electron-positron pairs survived.

This excess matched the excess of protons over antiprotons, in a condition known as baryon asymmetry , resulting in a net charge of zero for the universe.

This process peaked after about five minutes. Roughly one million years after the big bang, the first generation of stars began to form.

These antimatter particles immediately annihilate with electrons, releasing gamma rays. The net result is a steady reduction in the number of electrons, and a matching increase in the number of neutrons.

However, the process of stellar evolution can result in the synthesis of radioactive isotopes. Selected isotopes can subsequently undergo negative beta decay, emitting an electron and antineutrino from the nucleus.

At the end of its lifetime, a star with more than about 20 solar masses can undergo gravitational collapse to form a black hole.

However, quantum mechanical effects are believed to potentially allow the emission of Hawking radiation at this distance. Electrons and positrons are thought to be created at the event horizon of these stellar remnants.

When a pair of virtual particles such as an electron and positron is created in the vicinity of the event horizon, random spatial positioning might result in one of them to appear on the exterior; this process is called quantum tunnelling.

The gravitational potential of the black hole can then supply the energy that transforms this virtual particle into a real particle, allowing it to radiate away into space.

The rate of Hawking radiation increases with decreasing mass, eventually causing the black hole to evaporate away until, finally, it explodes.

Cosmic rays are particles traveling through space with high energies. The particle called a muon is a lepton produced in the upper atmosphere by the decay of a pion.

A muon, in turn, can decay to form an electron or positron. Remote observation of electrons requires detection of their radiated energy.

For example, in high-energy environments such as the corona of a star, free electrons form a plasma that radiates energy due to Bremsstrahlung radiation.

Electron gas can undergo plasma oscillation , which is waves caused by synchronized variations in electron density, and these produce energy emissions that can be detected by using radio telescopes.

The frequency of a photon is proportional to its energy. As a bound electron transitions between different energy levels of an atom, it absorbs or emits photons at characteristic frequencies.

For instance, when atoms are irradiated by a source with a broad spectrum, distinct absorption lines appear in the spectrum of transmitted radiation.

Each element or molecule displays a characteristic set of spectral lines, such as the hydrogen spectral series. Spectroscopic measurements of the strength and width of these lines allow the composition and physical properties of a substance to be determined.

In laboratory conditions, the interactions of individual electrons can be observed by means of particle detectors , which allow measurement of specific properties such as energy, spin and charge.

This enables precise measurements of the particle properties. For example, in one instance a Penning trap was used to contain a single electron for a period of 10 months.

The distribution of the electrons in solid materials can be visualized by angle-resolved photoemission spectroscopy ARPES. This technique employs the photoelectric effect to measure the reciprocal space —a mathematical representation of periodic structures that is used to infer the original structure.

ARPES can be used to determine the direction, speed and scattering of electrons within the material. Electron beams are used in welding.

This welding technique must be performed in a vacuum to prevent the electrons from interacting with the gas before reaching their target, and it can be used to join conductive materials that would otherwise be considered unsuitable for welding.

Electron-beam lithography EBL is a method of etching semiconductors at resolutions smaller than a micrometer.

For this reason, EBL is primarily used for the production of small numbers of specialized integrated circuits. Electron beam processing is used to irradiate materials in order to change their physical properties or sterilize medical and food products.

Linear particle accelerators generate electron beams for treatment of superficial tumors in radiation therapy. An electron beam can be used to supplement the treatment of areas that have been irradiated by X-rays.

Particle accelerators use electric fields to propel electrons and their antiparticles to high energies. These particles emit synchrotron radiation as they pass through magnetic fields.

The dependency of the intensity of this radiation upon spin polarizes the electron beam—a process known as the Sokolov—Ternov effect.

Synchrotron radiation can also cool the electron beams to reduce the momentum spread of the particles. Low-energy electron diffraction LEED is a method of bombarding a crystalline material with a collimated beam of electrons and then observing the resulting diffraction patterns to determine the structure of the material.

The electron microscope directs a focused beam of electrons at a specimen. Some electrons change their properties, such as movement direction, angle, and relative phase and energy as the beam interacts with the material.

Microscopists can record these changes in the electron beam to produce atomically resolved images of the material. This wavelength, for example, is equal to 0.

However, electron microscopes are expensive instruments that are costly to maintain. Two main types of electron microscopes exist: Transmission electron microscopes function like overhead projectors , with a beam of electrons passing through a slice of material then being projected by lenses on a photographic slide or a charge-coupled device.

Scanning electron microscopes rasteri a finely focused electron beam, as in a TV set, across the studied sample to produce the image.

The scanning tunneling microscope uses quantum tunneling of electrons from a sharp metal tip into the studied material and can produce atomically resolved images of its surface.

In the free-electron laser FEL , a relativistic electron beam passes through a pair of undulators that contain arrays of dipole magnets whose fields point in alternating directions.

The electrons emit synchrotron radiation that coherently interacts with the same electrons to strongly amplify the radiation field at the resonance frequency.

FEL can emit a coherent high- brilliance electromagnetic radiation with a wide range of frequencies, from microwaves to soft X-rays.

These devices are used in manufacturing, communication, and in medical applications, such as soft tissue surgery. Electrons are important in cathode ray tubes , which have been extensively used as display devices in laboratory instruments, computer monitors and television sets.

However, they have been largely supplanted by solid-state devices such as the transistor. From Wikipedia, the free encyclopedia.

For other uses, see Electron disambiguation. Hydrogen atom orbitals at different energy levels. The more opaque areas are where one is most likely to find an electron at any given time.

The proton—electron model of the nucleus. History of quantum mechanics. Electronics portal Physics portal Science portal.

Atomic and Molecular Spectroscopy. Since one part of the sphere would repel the other parts, the sphere contains electrostatic potential energy.

From electrostatics theory, the potential energy of a sphere with radius r and charge e is given by: For an electron with rest mass m 0 , the rest energy is equal to: Setting them equal and solving for r gives the classical electron radius.

The Physics of Atoms and Quanta: Introduction to Experiments and Theory. In other words, the projections of the spins of all electrons onto their momentum vector have the same sign.

A Biographical Approach to Theoretical Entities. University of Chicago Press. Histories of the Electron: The Birth of Microphysics.

This database was developed by J. Retrieved 10 September Atomic Structure and Lifetimes: National Institute of Standards and Technology.

Dictionary of Word Origins. The Story of Electrical and Magnetic Measurements: Including the Evolution of Physical Laboratories. The Basics of Physics.

Quarterly Journal of the Royal Astronomical Society. History of Electron Tubes. Retrieved 29 May The Historical Background of Chemistry. Journal of Nuclear Medicine.

Archived from the original PDF on Original publication in Russian: Reviews of Modern Physics. Physics of Atoms and Ions.

Journal of the American Chemical Society. European Journal of Physics. Die Naturwissenschaften in German. A Critical Account of Subatomic Reality.

Annalen der Physik in German. Proceedings of the Royal Society A. The Rise of the Standard Model: Particle Physics in the s and s.

The First Electron—Positron Collider". Atoms, Molecules, Nuclei and Particles. Handbook of Space Astronomy and Astrophysics 3rd ed. New Value for Electron Radius".

Optics, light and lasers: Beringer Particle Data Group ; et al. Knowing, The Nature of Physical Law. Or are they merely a mathematical bookkeeping device for quantum mechanics?

The Science of Empty Space. Fundamental Forces of Nature: The Story of Gauge Fields. International Journal of Theoretical Physics.

Introduction to Electrodynamics 3rd ed. American Journal of Physics. College Physics 4th ed. Radiation Physics and Chemistry. Flavor Physics for the Millennium.

Introduction to Magnetism and Magnetic Materials. Fundamental World of Quantum Chemistry: Canadian Journal of Chemistry.

Materials Science and Technology. The Discovery of Subatomic Particles. Introduction to phonons and electrons.

Fundamentals of Semiconductor Devices. The Theory of Transport Phenomena in Solids. Remove the obstacles that create electrical resistance, and you get ballistic electrons and a quantum surprise".

The Electronic Packaging Handbook. Quantum Physics of Matter: Journal of Superconductivity and Novel Magnetism. Stanford Linear Accelerator Center.

Selected Exercises in Particle and Nuclear Physics. The Origins of Life and the Universe. The Creation and Evolution of the Universe 3rd ed. Linking Inner Space and Outer Space".

Annual Review of Astronomy and Astrophysics. Reports on Progress in Physics. Archived from the original on August 17, Introduction to Modern Optics.

Archived from the original PDF on March 25, Archived from the original on December 7, Lawrence Livermore National Laboratory.

Manufacturing engineering and materials processing. Proceedings of the 16th Conference on Design automation.

Electron Beam Scanning in Industrial Applications. Journal of Nuclear Materials. Handbook of Accelerator Physics and Engineering. Reflection High-energy Electron Diffraction.

Journal of Scientific Instruments. Light and electron microscopy. Introduction to Health Physics. Principles and Techniques for Biologists.

Scanning and Transmission Electron Microscopy: An Introduction Reprint ed. Principles and Techniques for Biologists 2nd ed. Principles of Free-Electron Lasers.

Industry and Trade Summary. Up quark antiquark Down quark antiquark Charm quark antiquark Strange quark antiquark Top quark antiquark Bottom quark antiquark.

Photon Gluon W and Z bosons. Glueball Theta meson T meson. Mesonic molecule Pomeron Diquarks. Baryons Mesons Particles Quasiparticles Timeline of particle discoveries.

History of subatomic physics timeline Standard Model mathematical formulation Subatomic particles Particles Antiparticles Nuclear physics Eightfold Way Quark model Exotic matter Massless particle Relativistic particle Virtual particle Wave—particle duality.

Retrieved from " https: Electron Leptons Elementary particles Quantum electrodynamics Spintronics Charge carriers in science.

Views Read Edit View history.

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Such interaction between the light and free electrons is called Thomson scattering or linear Thomson scattering.

The relative strength of the electromagnetic interaction between two charged particles, such as an electron and a proton, is given by the fine-structure constant.

This value is a dimensionless quantity formed by the ratio of two energies: When electrons and positrons collide, they annihilate each other, giving rise to two or more gamma ray photons.

If the electron and positron have negligible momentum, a positronium atom can form before annihilation results in two or three gamma ray photons totalling 1.

This means that during weak interactions , electron neutrinos behave like electrons. Either member of this doublet can undergo a charged current interaction by emitting or absorbing a W and be converted into the other member.

Charge is conserved during this reaction because the W boson also carries a charge, canceling out any net change during the transmutation.

Charged current interactions are responsible for the phenomenon of beta decay in a radioactive atom. Both the electron and electron neutrino can undergo a neutral current interaction via a Z 0 exchange, and this is responsible for neutrino-electron elastic scattering.

An electron can be bound to the nucleus of an atom by the attractive Coulomb force. A system of one or more electrons bound to a nucleus is called an atom.

The wave-like behavior of a bound electron is described by a function called an atomic orbital. Each orbital has its own set of quantum numbers such as energy, angular momentum and projection of angular momentum, and only a discrete set of these orbitals exist around the nucleus.

According to the Pauli exclusion principle each orbital can be occupied by up to two electrons, which must differ in their spin quantum number.

Electrons can transfer between different orbitals by the emission or absorption of photons with an energy that matches the difference in potential.

The orbital angular momentum of electrons is quantized. Because the electron is charged, it produces an orbital magnetic moment that is proportional to the angular momentum.

The net magnetic moment of an atom is equal to the vector sum of orbital and spin magnetic moments of all electrons and the nucleus.

The magnetic moment of the nucleus is negligible compared with that of the electrons. The magnetic moments of the electrons that occupy the same orbital so called, paired electrons cancel each other out.

The chemical bond between atoms occurs as a result of electromagnetic interactions, as described by the laws of quantum mechanics.

These are electrons with opposed spins, allowing them to occupy the same molecular orbital without violating the Pauli exclusion principle much like in atoms.

Different molecular orbitals have different spatial distribution of the electron density. For instance, in bonded pairs i.

By contrast, in non-bonded pairs electrons are distributed in a large volume around nuclei. If a body has more or fewer electrons than are required to balance the positive charge of the nuclei, then that object has a net electric charge.

When there is an excess of electrons, the object is said to be negatively charged. When there are fewer electrons than the number of protons in nuclei, the object is said to be positively charged.

When the number of electrons and the number of protons are equal, their charges cancel each other and the object is said to be electrically neutral.

A macroscopic body can develop an electric charge through rubbing, by the triboelectric effect. Independent electrons moving in vacuum are termed free electrons.

Electrons in metals also behave as if they were free. In reality the particles that are commonly termed electrons in metals and other solids are quasi-electrons— quasiparticles , which have the same electrical charge, spin, and magnetic moment as real electrons but might have a different mass.

Likewise a current can be created by a changing magnetic field. At a given temperature, each material has an electrical conductivity that determines the value of electric current when an electric potential is applied.

Examples of good conductors include metals such as copper and gold, whereas glass and Teflon are poor conductors. In any dielectric material, the electrons remain bound to their respective atoms and the material behaves as an insulator.

Most semiconductors have a variable level of conductivity that lies between the extremes of conduction and insulation. The presence of such bands allows electrons in metals to behave as if they were free or delocalized electrons.

These electrons are not associated with specific atoms, so when an electric field is applied, they are free to move like a gas called Fermi gas [] through the material much like free electrons.

Because of collisions between electrons and atoms, the drift velocity of electrons in a conductor is on the order of millimeters per second.

Metals make relatively good conductors of heat, primarily because the delocalized electrons are free to transport thermal energy between atoms.

However, unlike electrical conductivity, the thermal conductivity of a metal is nearly independent of temperature. This is expressed mathematically by the Wiedemann—Franz law , [] which states that the ratio of thermal conductivity to the electrical conductivity is proportional to the temperature.

The thermal disorder in the metallic lattice increases the electrical resistivity of the material, producing a temperature dependence for electric current.

When cooled below a point called the critical temperature , materials can undergo a phase transition in which they lose all resistivity to electric current, in a process known as superconductivity.

In BCS theory , pairs of electrons called Cooper pairs have their motion coupled to nearby matter via lattice vibrations called phonons , thereby avoiding the collisions with atoms that normally create electrical resistance.

Electrons inside conducting solids, which are quasi-particles themselves, when tightly confined at temperatures close to absolute zero , behave as though they had split into three other quasiparticles: The speed of an electron can approach, but never reach, the speed of light in a vacuum, c.

However, when relativistic electrons—that is, electrons moving at a speed close to c —are injected into a dielectric medium such as water, where the local speed of light is significantly less than c , the electrons temporarily travel faster than light in the medium.

As they interact with the medium, they generate a faint light called Cherenkov radiation. The kinetic energy K e of an electron moving with velocity v is:.

The Big Bang theory is the most widely accepted scientific theory to explain the early stages in the evolution of the Universe. These photons were sufficiently energetic that they could react with each other to form pairs of electrons and positrons.

Likewise, positron-electron pairs annihilated each other and emitted energetic photons:. An equilibrium between electrons, positrons and photons was maintained during this phase of the evolution of the Universe.

After 15 seconds had passed, however, the temperature of the universe dropped below the threshold where electron-positron formation could occur.

Most of the surviving electrons and positrons annihilated each other, releasing gamma radiation that briefly reheated the universe.

For reasons that remain uncertain, during the annihilation process there was an excess in the number of particles over antiparticles. Hence, about one electron for every billion electron-positron pairs survived.

This excess matched the excess of protons over antiprotons, in a condition known as baryon asymmetry , resulting in a net charge of zero for the universe.

This process peaked after about five minutes. Roughly one million years after the big bang, the first generation of stars began to form.

These antimatter particles immediately annihilate with electrons, releasing gamma rays. The net result is a steady reduction in the number of electrons, and a matching increase in the number of neutrons.

However, the process of stellar evolution can result in the synthesis of radioactive isotopes. Selected isotopes can subsequently undergo negative beta decay, emitting an electron and antineutrino from the nucleus.

At the end of its lifetime, a star with more than about 20 solar masses can undergo gravitational collapse to form a black hole.

However, quantum mechanical effects are believed to potentially allow the emission of Hawking radiation at this distance. Electrons and positrons are thought to be created at the event horizon of these stellar remnants.

When a pair of virtual particles such as an electron and positron is created in the vicinity of the event horizon, random spatial positioning might result in one of them to appear on the exterior; this process is called quantum tunnelling.

The gravitational potential of the black hole can then supply the energy that transforms this virtual particle into a real particle, allowing it to radiate away into space.

The rate of Hawking radiation increases with decreasing mass, eventually causing the black hole to evaporate away until, finally, it explodes. Cosmic rays are particles traveling through space with high energies.

The particle called a muon is a lepton produced in the upper atmosphere by the decay of a pion. A muon, in turn, can decay to form an electron or positron.

Remote observation of electrons requires detection of their radiated energy. For example, in high-energy environments such as the corona of a star, free electrons form a plasma that radiates energy due to Bremsstrahlung radiation.

Electron gas can undergo plasma oscillation , which is waves caused by synchronized variations in electron density, and these produce energy emissions that can be detected by using radio telescopes.

The frequency of a photon is proportional to its energy. As a bound electron transitions between different energy levels of an atom, it absorbs or emits photons at characteristic frequencies.

For instance, when atoms are irradiated by a source with a broad spectrum, distinct absorption lines appear in the spectrum of transmitted radiation.

Each element or molecule displays a characteristic set of spectral lines, such as the hydrogen spectral series.

Spectroscopic measurements of the strength and width of these lines allow the composition and physical properties of a substance to be determined.

In laboratory conditions, the interactions of individual electrons can be observed by means of particle detectors , which allow measurement of specific properties such as energy, spin and charge.

This enables precise measurements of the particle properties. For example, in one instance a Penning trap was used to contain a single electron for a period of 10 months.

The distribution of the electrons in solid materials can be visualized by angle-resolved photoemission spectroscopy ARPES. This technique employs the photoelectric effect to measure the reciprocal space —a mathematical representation of periodic structures that is used to infer the original structure.

ARPES can be used to determine the direction, speed and scattering of electrons within the material. Electron beams are used in welding.

This welding technique must be performed in a vacuum to prevent the electrons from interacting with the gas before reaching their target, and it can be used to join conductive materials that would otherwise be considered unsuitable for welding.

Electron-beam lithography EBL is a method of etching semiconductors at resolutions smaller than a micrometer. For this reason, EBL is primarily used for the production of small numbers of specialized integrated circuits.

Electron beam processing is used to irradiate materials in order to change their physical properties or sterilize medical and food products.

Linear particle accelerators generate electron beams for treatment of superficial tumors in radiation therapy. An electron beam can be used to supplement the treatment of areas that have been irradiated by X-rays.

Particle accelerators use electric fields to propel electrons and their antiparticles to high energies. These particles emit synchrotron radiation as they pass through magnetic fields.

The dependency of the intensity of this radiation upon spin polarizes the electron beam—a process known as the Sokolov—Ternov effect.

Synchrotron radiation can also cool the electron beams to reduce the momentum spread of the particles. Low-energy electron diffraction LEED is a method of bombarding a crystalline material with a collimated beam of electrons and then observing the resulting diffraction patterns to determine the structure of the material.

The electron microscope directs a focused beam of electrons at a specimen. Some electrons change their properties, such as movement direction, angle, and relative phase and energy as the beam interacts with the material.

Microscopists can record these changes in the electron beam to produce atomically resolved images of the material. This wavelength, for example, is equal to 0.

However, electron microscopes are expensive instruments that are costly to maintain. Two main types of electron microscopes exist: Transmission electron microscopes function like overhead projectors , with a beam of electrons passing through a slice of material then being projected by lenses on a photographic slide or a charge-coupled device.

Scanning electron microscopes rasteri a finely focused electron beam, as in a TV set, across the studied sample to produce the image. The scanning tunneling microscope uses quantum tunneling of electrons from a sharp metal tip into the studied material and can produce atomically resolved images of its surface.

In the free-electron laser FEL , a relativistic electron beam passes through a pair of undulators that contain arrays of dipole magnets whose fields point in alternating directions.

The electrons emit synchrotron radiation that coherently interacts with the same electrons to strongly amplify the radiation field at the resonance frequency.

FEL can emit a coherent high- brilliance electromagnetic radiation with a wide range of frequencies, from microwaves to soft X-rays.

These devices are used in manufacturing, communication, and in medical applications, such as soft tissue surgery. Electrons are important in cathode ray tubes , which have been extensively used as display devices in laboratory instruments, computer monitors and television sets.

However, they have been largely supplanted by solid-state devices such as the transistor. From Wikipedia, the free encyclopedia.

For other uses, see Electron disambiguation. Hydrogen atom orbitals at different energy levels. The more opaque areas are where one is most likely to find an electron at any given time.

The proton—electron model of the nucleus. History of quantum mechanics. Electronics portal Physics portal Science portal. Atomic and Molecular Spectroscopy.

Since one part of the sphere would repel the other parts, the sphere contains electrostatic potential energy.

From electrostatics theory, the potential energy of a sphere with radius r and charge e is given by: For an electron with rest mass m 0 , the rest energy is equal to: Setting them equal and solving for r gives the classical electron radius.

The Physics of Atoms and Quanta: Introduction to Experiments and Theory. In other words, the projections of the spins of all electrons onto their momentum vector have the same sign.

A Biographical Approach to Theoretical Entities. University of Chicago Press. Histories of the Electron: The Birth of Microphysics. This database was developed by J.

Retrieved 10 September Atomic Structure and Lifetimes: National Institute of Standards and Technology. Dictionary of Word Origins.

The Story of Electrical and Magnetic Measurements: Including the Evolution of Physical Laboratories. The Basics of Physics. Quarterly Journal of the Royal Astronomical Society.

History of Electron Tubes. Retrieved 29 May The Historical Background of Chemistry. Journal of Nuclear Medicine. Archived from the original PDF on Original publication in Russian: Reviews of Modern Physics.

Physics of Atoms and Ions. Journal of the American Chemical Society. European Journal of Physics. Die Naturwissenschaften in German.

A Critical Account of Subatomic Reality. Annalen der Physik in German. Proceedings of the Royal Society A.

The Rise of the Standard Model: Particle Physics in the s and s. The First Electron—Positron Collider". Atoms, Molecules, Nuclei and Particles.

Handbook of Space Astronomy and Astrophysics 3rd ed. New Value for Electron Radius". Optics, light and lasers: Beringer Particle Data Group ; et al.

Knowing, The Nature of Physical Law. Or are they merely a mathematical bookkeeping device for quantum mechanics? The Science of Empty Space.

Fundamental Forces of Nature: The Story of Gauge Fields. International Journal of Theoretical Physics.

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