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Feb 21, 2015 · 3. At the present time in physics, the photon is an elementary particle, a member of the table of elementary particles that are the basis for the standard model of physics. Elementary particles included in the Standard Model. It has zero mass, zero charge and spin one, and it is the gauge boson of the electromagnetic interactions.
Aug 7, 2016 · According to quantum electrodynamics, the most accurately verified theory in physics, a photon is a single-particle excitation of the free quantum electromagnetic field. More formally, it is a state of the free electromagnetic field which is an eigenstate of the photon number operator with eigenvalue 1.
Oct 27, 2016 · Experimentally photons seem to behave as objects that have a size on the order of a few wavelengths. On the other hand, photons of a wavelength of roughly 500 500 - 1, 000 nm 1, 000 n m can be absorbed and emitted by atoms with dimensions of about 0.3 nm 0.3 n m. I guess if you think in terms of string theory you would say that the inherent ...
Dec 18, 2014 · Summary, (1) photon is not a wave, but it is the mutual energy flow. The mutual energy flow is built by the retarded wave sends from an emitter and the advanced wave sends from an absorber. (2) there are 4 waves, retarded wave, advanced wave and two time-reversal waves. All 4 waves cancel each other.
May 26, 2015 · 10. The 4-momentum is defined as p = mU p = m U where m is the rest mass of the particle and U U is the 4-velocity. Now I am confused as to how this applies to a photon for which one can't define U U since there can be no rest frame for a photon. I'm trying to see why p p is still tangential to it's world line in any frame.
Etot = Mc2 E t o t = M c 2. we can think about a photon as having "an effective" mass. Meff = E/c2 M e f f = E / c 2. However, this fact does NOT mean the photon has "mass". It only means that its energetic content can be "seen" in terms of mass due to the equivalence of energy and matter.
Dec 22, 2014 · The connection is that an electromagnetic wave describes the probability of finding a photon with given energy, momentum and spin. A circularly parised plane wave predicts that only photons with parallel, or antiparallel depending on the sense of the polarisation, spin will be found. A linearly polarized plane wave predicts an equal amount of ...
Nov 19, 2020 · So this assumes photon-photon scattering process or a pair-production reaction : $$ \gamma_1 + \gamma_2 \to e^+ e^- $$ or as a Feynman diagram : Pitty that this process involves highly-energetic photons, with order of couple dozen $\text{GeV}$ energy. That much energy can be only produced in CERN or similar particle accelerator laboratories.
Sep 29, 2016 · A single photon is described quantum mechanically by the Maxwell equations, where the solutions are taken to be complex. The Maxwell equations can be written in the form of the matrix Dirac equation, where the Pauli two-component matrices, corresponding to spin 1/2 electrons, are replaced by analogous three-component matrices, corresponding to spin 1 photons.
One nice way to put the problem is if you have an atom (single-electron for simplicity) interacting with photons at some wavelength below X-rays. The electric field of a given mode of the radiation can be written, classically, in the form. E(r, t) = E0a(t)eik⋅r +, E (r, t) = E 0 a (t) e i k ⋅ r +, where a(t) a (t) is the interesting ...
