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Antimatter

Antimatter
In particle physics, antimatter is material composed of antiparticles, which have the same mass as particles of ordinary matter but have opposite charge and other particle properties such as lepton and baryon number. Encounters between particles and antiparticles lead to the annihilation of both, giving rise to varying proportions of high-energy photons (gamma rays), neutrinos, and lower-mass particle–antiparticle pairs. Setting aside the mass of any product neutrinos, which represent released energy which generally continues to be unavailable, the end result of annihilation is a release of energy available to do work, proportional to the total matter and antimatter mass, in accord with the mass-energy equivalence equation, E=mc2.[1] Antiparticles bind with each other to form antimatter just as ordinary particles bind to form normal matter. For example, a positron (the antiparticle of the electron) and an antiproton can form an antihydrogen atom. History of the concept Notation Positrons

Higgs Boson particle discovery explained by scientists and journalists. Tomorrow at 3 a.m. EST, our understanding of the universe is likely to change. That’s when physicists working at the Large Hadron Collider in Switzerland, just over the border from France, will announce the latest results of the decades-long search for a fundamental particle called the Higgs boson—and the word on the street is that they’ve found it (or, at least, something very much fitting the bill). J. Bryan Lowder is a Slate assistant editor. Follow But why should anyone without an advanced degree in particle physics stay up late to catch the official news? Anyway, here’s the part where I’m supposed to explain what, exactly, the Higgs boson and the associated Higgs field actually are. Not clear enough? As it turns out, however, theoretical physicist Peter Higgs, the particle’s namesake, actually doesn’t care for these viscous examples. Burton DeWilde, a friend of mine who is a Ph.D. candidate in physics, relayed another variation on this theme: Imagine a room full of physicists.

Basic facts (Gay money: The truth about lesbian & gay economics ¶ Joe Clark) Basic facts I spent six months in 2010 reading and summarizing every article on lesbian and gay economics published since the 1990s. I took on this project to counter a myth. Myth: Gays are rich The myth of gay money holds that “gays” (really just gay males) are high-income or rich. This myth was relentlessly propagated through the 1990s and persists today. Reality: Gay males earn less and lesbians earn more than straight people Most of the dozens of studies of income and earnings of gay men and lesbians show consistent results. Weak statement: Neither gay males nor lesbians earn more than straight people. Either way, most of the data shows that gay males do not earn more than straight people. Why? Why do gay males have generally lower incomes than straight males? Gay males have more education than straight males, but they do not choose male-dominated professions as often as straight males do. Why do lesbians generally have higher income than straight females? What about discrimination?

Cosmogony Cosmogony (or cosmogeny) is any model concerning the coming-into-existence (i.e. origin) of either the cosmos (i.e. universe), or the so-called reality of sentient beings.[1][2] Developing a complete theoretical model has implications in both the philosophy of science and epistemology. Etymology[edit] The word comes from the Koine Greek κοσμογονία (from κόσμος "cosmos, the world") and the root of γί(γ)νομαι / γέγονα ("come into a new state of being").[3] In astronomy, cosmogony refers to the study of the origin of particular astrophysical objects or systems, and is most commonly used in reference to the origin of the universe, the solar system, or the earth-moon system.[1][2] Overview[edit] The Big Bang theory is the prevailing cosmological model of the early development of the universe.[4] The most commonly held view is that the universe was once a gravitational singularity, which expanded extremely rapidly from its hot and dense state. Cosmologist and science communicator Sean M.

Physics 20b: Introduction to Cosmology - Spring 2010 - Download free content from UC Irvine Diphallus is a rare condition in which a man’s penis is duplicated. The first known case of this condition was reported in 1609. Typically only one of the organs is fully formed, but there have been occurrences in which both penises are fully functional! The first known case of this condition was reported in 1609. Typically only one of the organs is fully formed, but there have been occurrences in which both penises are fully functional! This strange disorder affects an estimated 1 in 5.5 million men. It's very uncommon for both penises in diphallus to be fully functional. Usually one of them only has rudimentary functionality. While it might sound awesome, most people would rather not have it. For more info about diphallus check out this scientific journal article.

Prenatal memory Prenatal memory, also called fetal memory, is important for the development of memory in humans. Many factors can impair fetal memory and its functions, primarily maternal actions. There are multiple techniques available not only to demonstrate the existence of fetal memory but to measure it. Fetal memory is vulnerable to certain diseases so much so that exposure can permanently damage the development of the fetus and even terminate the pregnancy by aborting the fetus. Background Information and Functions[edit] Fetal memory is integral to mother-infant attachment There is substantial evidence that fetal memory exists within the first and second trimester after conception when the egg is fertilized. Development[edit] The Central Nervous System (CNS) and memory in the fetus develop from the ectoderm following fertilization via a process called neurulation. Functions[edit] Measurement techniques[edit] There are considered to be three paradigms used to investigate fetal learning and memory.

Relativistic Baseball What would happen if you tried to hit a baseball pitched at 90% the speed of light? - Ellen McManis Let’s set aside the question of how we got the baseball moving that fast. We'll suppose it's a normal pitch, except in the instant the pitcher releases the ball, it magically accelerates to 0.9c. From that point onward, everything proceeds according to normal physics. The answer turns out to be “a lot of things”, and they all happen very quickly, and it doesn’t end well for the batter (or the pitcher). The ball is going so fast that everything else is practically stationary. The ideas of aerodynamics don’t apply here. These gamma rays and debris expand outward in a bubble centered on the pitcher’s mound. The constant fusion at the front of the ball pushes back on it, slowing it down, as if the ball were a rocket flying tail-first while firing its engines. After about 70 nanoseconds the ball arrives at home plate. Suppose you’re watching from a hilltop outside the city.

Magyar aszú a világ 100 legjobb bora között Börtön az ilyen munkahely Pusztába vezet az újraiparosítás. Riport a bezárt gödi Samsung gyár környékéről. 2014. április 8. kedd 18:54 Vége a pálinka-szabadságharcnak Az előző kormány mindenkinek megengedte, hogy jó sok pálinkát főzzön otthon. 2014. április 10. csütörtök 08:38 A szürke eminenciás, akit eltitkoltak a horvát ügyészek elől A magyar energetika nemzetközi szaktekintélye, de nevét alig ismerik, pedig évtizedek óta milliárdok folynak át kezei között. 2014. április 10. csütörtök 05:36 Magyar süteményeket tiltottak be A gávavencsellői üzem néhány termékében a megengedett tartósítószer-mennyiség kétszerese van. 2014. április 10. csütörtök 16:56 Folytathatják tovább ugyanígy A választással minden marad a régiben a gazdaságban is. 2014. április 13. vasárnap 14:12 Vége a plázáknak Mutatjuk a képeket az USA szürreálisan kihalt, hatalmas épületeiről. 2014. április 11. péntek 18:54 Eltűnt Berlusconi jobbkeze Dell'Utrival alapították a pártot, most eltűnt a fontos vállalkozó. Ezzel büszkélkedik a NAV

String theory String theory was first studied in the late 1960s[3] as a theory of the strong nuclear force before being abandoned in favor of the theory of quantum chromodynamics. Subsequently, it was realized that the very properties that made string theory unsuitable as a theory of nuclear physics made it a promising candidate for a quantum theory of gravity. Five consistent versions of string theory were developed until it was realized in the mid-1990s that they were different limits of a conjectured single 11-dimensional theory now known as M-theory.[4] Many theoretical physicists, including Stephen Hawking, Edward Witten and Juan Maldacena, believe that string theory is a step towards the correct fundamental description of nature: it accommodates a consistent combination of quantum field theory and general relativity, agrees with insights in quantum gravity (such as the holographic principle and black hole thermodynamics) and has passed many non-trivial checks of its internal consistency.

How Time Dilation Makes Sense previous home next PDF Michael Fowler, UVa Physics, 12/1/07 “Moving Clocks Run Slow” plus “Moving Clocks Lose Synchronization” plus “Length Contraction” leads to consistency! The object of this exercise is to show explicitly how it is possible for two observers in inertial frames moving relative to each other at a relativistic speed to each see the other’s clocks as running slow and as being unsynchronized, and yet if they both look at the same clock at the same time from the same place (which may be far from the clock), they will agree on what time it shows! Suppose that in Jack’s frame we have two synchronized clocks C1 and C2 set 18 x 108 meters apart (that’s about a million miles, or 6 light-seconds). Jill’s spaceship, carrying a clock C', is traveling at 0.6c, that is 1.8 x 108 meters per second, parallel to the line C1C2, passing close by each clock. Suppose C' is synchronized with C1 as they pass, so both read zero. What does clock C' (the clock on the ship) read as it passes C2?

First Known Photo of a Human (2 pics) Pics | 1 Nov, 2010 | Views: 9703 | It is the first known photo of a human. This is a Daguerreotype taken by the inventor of the process, Louis Daguerre, in 1838. This man stood still long enough to have his boots shined. Do you like it? It is just one of the thousands of posts that we have on the Acidcow.com. What Wavelength Goes With a Color? Colors We Can't See There are many wavelengths in the electromagnetic spectrum the human eye cannot detect. Energy with wavelengths too short for humans to see Energy with wavelengths too short to see is "bluer than blue". How do we know this light exists? Energy with wavelengths too long for humans to see Energy whose wavelength is too long to see is "redder than red". How do we know this kind of light exists? Very long wavelengths of infrared light radiate heat to outer space.

Electricity & Magnetism - Download free content from MIT

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