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The Feynman Lectures on Physics. PHYSICS MAP. Pauli exclusion principle. A more rigorous statement is that the total wave function for two identical fermions is antisymmetric with respect to exchange of the particles.

Pauli exclusion principle

This means that the wave function changes its sign if the space and spin co-ordinates of any two particles are interchanged. Particles with an integer spin, or bosons, are not subject to the Pauli exclusion principle: any number of identical bosons can occupy the same quantum state, as with, for instance, photons produced by a laser and Bose–Einstein condensate. Overview[edit] Astronomers discover closest potentially habitable planet: Wolf 1061c. The closest potentially habitable planet ever found has been spotted by Australian scientists, and it's just 14 light-years away.

Astronomers discover closest potentially habitable planet: Wolf 1061c

That’s 126 trillion kilometres from Earth, which sounds impossibly far, but when you consider that our closest planetary neighbour, Mars, is 249 million km away, that handful of light-years doesn’t seem so bad in the scheme of things. Named Wolf 1061c, the newly discovered planet is located in the constellation Ophiucus, and its star is the 35th closest star from Earth - that we know about.

The team behind the discovery says it's orbiting a red dwarf 'M-type' star called Wolf 1061, alongside two other planets. Femtotechnology. Femtotechnology is a hypothetical term used in reference to structuring of matter on the scale of a femtometer, which is 10−15 m.


This is a smaller scale in comparison to nanotechnology and picotechnology which refer to 10−9 m and 10−12 m respectively. Overview[edit] Work in the femtometer range involves manipulation of excited energy states within atomic nuclei, specifically nuclear isomers, to produce metastable (or otherwise stabilized) states with unusual properties. Quantum entanglement. Quantum entanglement is a physical phenomenon that occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently – instead, a quantum state may be given for the system as a whole.

Quantum entanglement

Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky and Nathan Rosen,[1] describing what came to be known as the EPR paradox, and several papers by Erwin Schrödinger shortly thereafter.[2][3] Einstein and others considered such behavior to be impossible, as it violated the local realist view of causality (Einstein referred to it as "spooky action at a distance"),[4] and argued that the accepted formulation of quantum mechanics must therefore be incomplete.

History[edit] However, they did not coin the word entanglement, nor did they generalize the special properties of the state they considered. Satyendra Nath Bose. Satyendra Nath Bose, FRS[2] (1 January 1894 – 4 February 1974) was an Indian physicist specialising in mathematical physics.

Satyendra Nath Bose

He is best known for his work on quantum mechanics in the early 1920s, providing the foundation for Bose–Einstein statistics and the theory of the Bose–Einstein condensate. A Fellow of the Royal Society, he was awarded India's second highest civilian award, the Padma Vibhushan in 1954 by the Government of India.[5][6] The class of particles that obey Bose–Einstein statistics, bosons, was named after Bose by Paul Dirac.[7][8] A self-taught scholar and a polyglot, he had a wide range of interests in varied fields including physics, mathematics, chemistry, biology, mineralogy, philosophy, arts, literature, and music.

He served on many research and development committees in independent India. Gluon. Richard Feynman. He assisted in the development of the atomic bomb during World War II and became known to a wide public in the 1980s as a member of the Rogers Commission, the panel that investigated the Space Shuttle Challenger disaster.

Richard Feynman

In addition to his work in theoretical physics, Feynman has been credited with pioneering the field of quantum computing,[5] and introducing the concept of nanotechnology. He held the Richard C. Tolman professorship in theoretical physics at the California Institute of Technology. Feynman was a keen popularizer of physics through both books and lectures, including a 1959 talk on top-down nanotechnology called There's Plenty of Room at the Bottom, and the three-volume publication of his undergraduate lectures, The Feynman Lectures on Physics. Feynman also became known through his semi-autobiographical books Surely You're Joking, Mr. Introduction to quantum mechanics. This article is a non-technical introduction to the subject.

Introduction to quantum mechanics

For the main encyclopedia article, see Quantum mechanics. In this sense, the word quantum means the minimum amount of any physical entity involved in an interaction. Certain characteristics of matter can take only discrete values. Some aspects of quantum mechanics can seem counterintuitive or even paradoxical, because they describe behaviour quite different from that seen at larger length scales.

Uncertainty principle. Introduced first in 1927, by the German physicist Werner Heisenberg, it states that the more precisely the position of some particle is determined, the less precisely its momentum can be known, and vice versa.[1] The formal inequality relating the standard deviation of position σx and the standard deviation of momentum σp was derived by Earle Hesse Kennard[2] later that year and by Hermann Weyl[3] in 1928:

Uncertainty principle

Wave–particle duality. Origin of theory[edit] The idea of duality originated in a debate over the nature of light and matter that dates back to the 17th century, when Christiaan Huygens and Isaac Newton proposed competing theories of light: light was thought either to consist of waves (Huygens) or of particles (Newton).

Wave–particle duality

Through the work of Max Planck, Albert Einstein, Louis de Broglie, Arthur Compton, Niels Bohr, and many others, current scientific theory holds that all particles also have a wave nature (and vice versa).[2] This phenomenon has been verified not only for elementary particles, but also for compound particles like atoms and even molecules. For macroscopic particles, because of their extremely short wavelengths, wave properties usually cannot be detected.[3] Brief history of wave and particle viewpoints[edit] Quantum tunnelling. Quantum tunnelling or tunneling (see spelling differences) refers to the quantum mechanical phenomenon where a particle tunnels through a barrier that it classically could not surmount.

Quantum tunnelling

This plays an essential role in several physical phenomena, such as the nuclear fusion that occurs in main sequence stars like the Sun.[1] It has important applications to modern devices such as the tunnel diode,[2] quantum computing, and the scanning tunnelling microscope. The effect was predicted in the early 20th century and its acceptance as a general physical phenomenon came mid-century.[3] Tunnelling is often explained using the Heisenberg uncertainty principle and the wave–particle duality of matter.

Pure quantum mechanical concepts are central to the phenomenon, so quantum tunnelling is one of the novel implications of quantum mechanics. History[edit] Superpartner. In particle physics, a Superpartner (also sparticle) is a hypothetical elementary particle. Supersymmetry is one of the synergistic theories in current high-energy physics that predicts the existence of these "shadow" particles.[1][2] The word sparticle features the s- prefix which is used to form names of superpartners of the individual fermions, e.g. the stop quark. Theoretical predictions[edit] According to the supersymmetry theory, each fermion should have a partner boson, the fermion's superpartner, and each boson should have a partner fermion.

Exact unbroken supersymmetry would predict that a particle and its superpartners would have the same mass. Tachyon. Because a tachyon would always move faster than light, it would not be possible to see it approaching. After a tachyon has passed nearby, we would be able to see two images of it, appearing and departing in opposite directions. Black Knight satellite. Photo of a thermal blanket let go from the International Space Station during STS-88; claimed by conspiracy theorists to be the Black Knight satellite. The Black Knight satellite is claimed by some conspiracy theorists[1] to be an object approximately 13,000 years old of extraterrestrial origin orbiting Earth in near-polar orbit. Critics and mainstream academics have called it a conspiracy theory and a myth.[2][3] Cosmic ray. Cosmic ray flux versus particle energy The term ray is an historical accident, as cosmic rays were at first, and wrongly, thought to be mostly electromagnetic radiation.

In common scientific usage[4] high-energy particles with intrinsic mass are known as "cosmic" rays, while photons, which are quanta of electromagnetic radiation (and so have no intrinsic mass) are also known by their common names, such as "gamma rays" or "X-rays", depending on their origin. Of primary cosmic rays, which originate outside of Earth's atmosphere, about 99% are the nuclei (stripped of their electron shells) of well-known atoms, and about 1% are solitary electrons (similar to beta particles). Of the nuclei, about 90% are simple protons, i. e. hydrogen nuclei; 9% are alpha particles, and 1% are the nuclei of heavier elements, called HZE ions.[10] A very small fraction are stable particles of antimatter, such as positrons or antiprotons.

The Standard Model of Particle Physics. How Big Is Space – Interactive version. Giant Magellan Telescope. The Giant Magellan Telescope (GMT) is a ground-based extremely large telescope planned for completion in 2025.[5] It will consist of seven 8.4 m (27.6 ft) diameter primary segments,[6] with the resolving power of a 24.5 m (80.4 ft) primary mirror and collecting area equivalent to a 22.0 m (72.2 ft) one,[7] (which is about 368 square meters).[4] The telescope is expected to have over five to ten times the light-gathering ability of existing instruments. Three mirrors have been cast and the mountain top is being prepared for construction.[8][9] A total of seven primary mirrors are planned, but it can begin operation with four.[9] Site[edit] Top 10 Unexplained Mysteries of the Stars.

Space. Eta Carinae. Coordinates: 10h 45m 03.591s, −59° 41′ 04.26″ Observational history[edit] 67P/Churyumov–Gerasimenko. 67P/Churyumov–Gerasimenko (abbreviated as 67P or 67P/C-G, and written in Cyrillic as комета Чурюмова — Герасименко) is a comet, originally from the Kuiper belt,[6] with a current orbital period of 6.45 years,[1] a rotation period of approximately 12.4 hours[5] and a maximum velocity of 135,000 km/h (38 km/s; 84,000 mph).[7] Churyumov–Gerasimenko is approximately 4.3 by 4.1 km (2.7 by 2.5 mi) at its longest and widest dimensions.[8] It was first observed on photographic plates in 1969 by Soviet astronomers Klim Ivanovych Churyumov and Svetlana Ivanovna Gerasimenko, after whom it is named. It came to perihelion (closest approach to the Sun) on 13 August 2015.[9][10][11][12] Discovery[edit] Eta Carinae.

Carina Nebula. Coordinates: 10h 45m 08.5s, −59° 52′ 04″ "Eta Carinae Nebula" redirects here. History of string theory. The history of string theory spans several decades of intense research including two superstring revolutions. Through the combined efforts of many different researchers, string theory has developed into a broad and varied subject with connections to quantum gravity, particle and condensed matter physics, cosmology, and pure mathematics.

D-brane. Fermi Gamma-ray Space Telescope. The Fermi Gamma-ray Space Telescope (FGST[2]), formerly called the Gamma-ray Large Area Space Telescope (GLAST), is a space observatory being used to perform gamma-ray astronomy observations from low Earth orbit. Its main instrument is the Large Area Telescope (LAT), with which astronomers mostly intend to perform an all-sky survey studying astrophysical and cosmological phenomena such as active galactic nuclei, pulsars, other high-energy sources and dark matter. Hypercube. Eaa wimps machos. Gravitational lens. Dark Matter Core Defies Explanation in Hubble Image (03/02/2012) - The Full Story. Cosmological constant. Planck Mission Brings Universe Into Sharp Focus. Dark energy. Lambda-CDM model. If the Moon Were Only 1 Pixel - A tediously accurate map of the solar system.

James Webb Space Telescope (JWST) NASA. How old do I look? These Are Some of the Most Ancient and Distant Galaxies Ever Discovered—And They're Glorious. Dark matter. Neutrino. Cosmic Megastructures - Could We Build a Dyson Sphere? Spectroscopy. Timeline of space exploration. Time dilation. How-to-imagine-the-tenth-dimension.

The Fermi Paradox.