Perturbation theory (quantum mechanics)
In the theory of quantum electrodynamics (QED), in which the electron–photon interaction is treated perturbatively, the calculation of the electron's magnetic moment has been found to agree with experiment to eleven decimal places. In QED and other quantum field theories, special calculation techniques known as Feynman diagrams are used to systematically sum the power series terms. The problem of non-perturbative systems has been somewhat alleviated by the advent of modern computers.

Quantum mechanics
Solution to Schrödinger's equation for the hydrogen atom at different energy levels. The brighter areas represent a higher probability of finding an electron Quantum mechanics gradually arose from Max Planck's solution in 1900 to the black-body radiation problem (reported 1859) and Albert Einstein's 1905 paper which offered a quantum-based theory to explain the photoelectric effect (reported 1887).

Bosonic string theory
Bosonic string theory is the original version of string theory, developed in the late 1960s. In the early 2000s, supersymmetry was discovered in the context of string theory, and a new version of string theory called superstring theory (supersymmetric string theory) became the real focus. Nevertheless, bosonic string theory remains a very useful "toy model" to understand many general features of perturbative string theory, and string theory textbooks usually start with the bosonic string. The first volume of Polchinski's String Theory and Zwiebach's A First Course in String Theory are good examples. Problems[edit] Although bosonic string theory has many attractive features, it falls short as a viable physical model in two significant areas and is forced to posit a 26 dimensional spacetime to remedy inconsistencies.

Retired Military Personnel To Confirm UFO Incursions at American Nuclear Weapons Sites
Consider it the second barrel of the double-barreled shotgun, or the "two" of the proverbial "one-two punch"; the first being Leslie Kean's new book, and now the upcoming press conference being co-hosted by researcher Robert Hastings and former missleer (Minuteman I launch officer - Deputy Missile Combat Crew Commander) Bob Salas. Hastings writes: "Declassified U.S. government documents and the testimony of more than 120 former or retired military personnel have established, beyond doubt, the reality of ongoing UFO incursions at American nuclear weapons sites. While most of the incidents apparently involved mere surveillance, in a few cases a significant number of nuclear missiles suddenly and simultaneously malfunctioned, just as USAF Security Policemen reported seeing disc-shaped craft hovering nearby. On September 27th, during a press conference at the National Press Club in Washington D.C. , six former U.S. At the press conference, Mr.

Frequency
Three cyclically flashing lights, from lowest frequency (top) to highest frequency (bottom). f is the frequency in hertz (Hz), meaning the number of cycles per second. T is the period in seconds (s), meaning the number of seconds per cycle. T and f are reciprocals. In some fields, especially where frequency-domain analysis is used, the concept of frequency is applied only to sinusoidal phenomena, since in linear systems more complex periodic and nonperiodic phonomena are most easily analyzed in terms of sums of sinusoids of different frequencies. Definitions and units[edit]
Landau theory
Landau theory in physics was introduced by Lev Landau in an attempt to formulate a general theory of continuous (i.e. second-order) phase transitions.[1] Mean-field formulation (no long-range correlation)[edit] Landau was motivated to suggest that the free energy of any system should obey two conditions: it is analyticit obeys the symmetry of the Hamiltonian Given these two conditions, one can write down (in the vicinity of the critical temperature, Tc) a phenomenological expression for the free energy as a Taylor expansion in the order parameter.

Subatomic Particles
Paul Davies, a cosmologist at Arizona State University in Tempe, admires the fact that Aharonov’s team has always striven to verify its claims experimentally. “This isn’t airy-fairy philosophy—these are real experiments,” he says. Davies has now joined forces with the group to investigate the framework’s implications for the origin of the cosmos (See “Does the Universe Have a Destiny?”
Giant natural particle accelerator discovered above thun
(PhysOrg.com) -- A lightning researcher at the University of Bath has discovered that during thunderstorms, giant natural particle accelerators can form 40 km above the surface of the Earth. Dr Martin Füllekrug from the University’s Department of Electronic & Electrical Engineering presented his new work on Wednesday 14 April at the Royal Astronomical Society National Astronomy Meeting (RAS NAM 2010) in Glasgow. His findings show that when particularly intense lightning discharges in thunderstorms coincide with high-energy particles coming in from space (cosmic rays), nature provides the right conditions to form a giant particle accelerator above the thunderclouds. The cosmic rays strip off electrons from air molecules and these electrons are accelerated upwards by the electric field of the lightning discharge. The free electrons and the lightning electric field then make up a natural particle accelerator. Explore further: Remnants of Tropical Depression Peipah still raining on Philippines