Two-photon physics, also called gamma–gamma physics, is a branch of particle physics that describes the interactions between two photons. Normally, beams...

example, two photons may interact indirectly through virtual electron–positron pairs. Such photon–photon scattering (see two-photon physics), as well...

In atomic physics, two-photon absorption (TPA or 2PA), also called two-photon excitation or non-linear absorption, is the (almost) simultaneous absorption...

In physics, a photon gas is a gas-like collection of photons, which has many of the same properties of a conventional gas like hydrogen or neon – including...

particles precipitating out of colliding photon jets (see two-photon physics). Currently, two-photon physics studies creation of various fermion pairs...

Model of Particle Physics with a new abelian U(1) gauge symmetry. The corresponding new spin-1 gauge boson (i.e., the dark photon) can then couple very...

Two-photon excitation microscopy (TPEF or 2PEF) is a fluorescence imaging technique that is particularly well-suited to image scattering living tissue...

chamber, leading to the 1948 Nobel Prize in Physics. If the photon is near an atomic nucleus, the energy of a photon can be converted into an electron–positron...

attraction between two charges—can be thought of as resulting from the exchange of virtual photons between the charges. Virtual photons are the exchange...

electron–positron creation, is a form of pair production governed by two-photon physics. Bhabha scattering Pair production Annihilation radiation Meitner–Hupfeld...

In atomic physics, non-degenerate two-photon absorption (ND-TPA or ND-2PA) or two-color two-photon excitation is a type of two-photon absorption (TPA)...

Photon energy is transferred to matter in a two-step process. First, energy is transferred to charged particles in the medium through various photon interactions...

single-photon source (also known as a single photon emitter) is a light source that emits light as single particles or photons. Single-photon sources...

Virtual photons are a fundamental concept in particle physics and quantum field theory that play a crucial role in describing the interactions between...

Physics is a branch of science in which the primary objects of study are matter and energy. These topics were discussed across many cultures in ancient...

Particle physics or high-energy physics is the study of fundamental particles and forces that constitute matter and radiation. The field also studies combinations...

Time-resolved two-photon photoelectron (2PPE) spectroscopy is a time-resolved spectroscopy technique which is used to study electronic structure and electronic...

The photon structure function, in quantum field theory, describes the quark content of the photon. While the photon is a massless boson, through certain...

unsolved problems grouped into broad areas of physics. Some of the major unsolved problems in physics are theoretical, meaning that existing theories...

(not including dark matter), mostly photons and other massless force carriers. The Standard Model of particle physics contains 12 flavors of elementary...

needed] into two leptons (electrons or muons) and a photon (ℓℓγ), via virtual photon decay. This can happen in three ways; Higgs to virtual photon to ℓℓγ in...

particle physics, a massless particle is an elementary particle whose invariant mass is zero. At present the only confirmed massless particle is the photon. The...

In particle physics, a boson (/ˈboʊzɒn/ /ˈboʊsɒn/) is a subatomic particle whose spin quantum number has an integer value (0, 1, 2, ...). Bosons form...

physics, the Hanbury Brown and Twiss (HBT) effect is any of a variety of correlation and anti-correlation effects in the intensities received by two detectors...

In chemistry, nuclear physics, and particle physics, inelastic scattering is a process in which the internal states of a particle or a system of particles...

electrons with photons. The π0 was identified definitively at the University of California's cyclotron in 1949 by observing its decay into two photons. Later...

even smaller particles such as quarks. Particle physics studies these smallest particles; nuclear physics studies atomic nuclei and their (immediate) constituents:...

Atomic, molecular, and optical physics (AMO) is the study of matter–matter and light–matter interactions, at the scale of one or a few atoms and energy...

L. (1 March 1999). "Quantum effects in one-photon and two-photon interference". Reviews of Modern Physics. 71 (2): S274 – S282. Bibcode:1999RvMPS..71...

 Photon propulsion has been considered to be one of the best available interstellar propulsion concepts, because it is founded on established physics and...