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Double-slit experiment

Double-slit experiment
The double-slit experiment is a demonstration that light and matter can display characteristics of both classically defined waves and particles; moreover, it displays the fundamentally probabilistic nature of quantum mechanical phenomena. The experiment belongs to a general class of "double path" experiments, in which a wave is split into two separate waves that later combine back into a single wave. Changes in the path lengths of both waves result in a phase shift, creating an interference pattern. Another version is the Mach–Zehnder interferometer, which splits the beam with a mirror. This experiment is sometimes referred to as Young's experiment and while there is no doubt that Young's demonstration of optical interference, using sunlight, pinholes and cards, played a vital part in the acceptance of the wave theory of light, there is some question as to whether he ever actually performed a double-slit interference experiment.[1] Overview[edit] Variations of the experiment[edit] Related:  Founding experimentsCuriosidades

Radioactive decay Alpha decay is one example type of radioactive decay, in which an atomic nucleus emits an alpha particle, and thereby transforms (or 'decays') into an atom with a mass number decreased by 4 and atomic number decreased by 2. Many other types of decays are possible. Radioactive decay, also known as nuclear decay or radioactivity, is the process by which a nucleus of an unstable atom loses energy by emitting particles of ionizing radiation. A material that spontaneously emits this kind of radiation—which includes the emission of energetic alpha particles, beta particles, and gamma rays—is considered radioactive. Radioactive decay is a stochastic (i.e. random) process at the level of single atoms, in that, according to quantum theory, it is impossible to predict when a particular atom will decay.[1] However, the chance that a given atom will decay is constant over time. There are many different types of radioactive decay (see table below). Discovery and history[edit] Types of decay[edit]

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. 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. Concept[edit] Meaning of entanglement[edit] Apparent paradox[edit] The hidden variables theory[edit]

The most beautiful death Brave New World novelist Aldous Huxley was diagnosed with cancer in 1960, at which point his health slowly began to deteriorate. On his deathbed in November of 1963, just as he was passing away, Aldous — a man who for many years had been fascinated with the effects of psychedelic drugs since being introduced to mescaline in 1953 — asked his wife Laura to administer him with LSD. She agreed. The following letter — an incredibly moving, detailed account of Aldous's last days — was written by Laura just days after her husband's death and sent to his older brother Julian. Transcript follows. 6233 Mulholland Highway Los Angeles 28, California December 8, 1963Dearest Julian and Juliette:There is so much I want to tell you about the last week of Aldous' life and particularly the last day.

Thomas Young (scientist) Thomas Young (13 June 1773 – 10 May 1829) was an English polymath. Young made notable scientific contributions to the fields of vision, light, solid mechanics, energy, physiology, language, musical harmony, and Egyptology. He "made a number of original and insightful innovations"[1] in the decipherment of Egyptian hieroglyphs (specifically the Rosetta Stone) before Jean-François Champollion eventually expanded on his work. Young belonged to a Quaker family of Milverton, Somerset, where he was born in 1773, the eldest of ten children. Young began to study medicine in London in 1792, moved to Edinburgh in 1794, and a year later went to Göttingen, Lower Saxony, Germany where he obtained the degree of doctor of physics in 1796. In 1801 Young was appointed professor of natural philosophy (mainly physics) at the Royal Institution. Thomas Young died in London on 10 May 1829, and was buried in the cemetery of St. Young was highly regarded by his friends and colleagues.

First Quantum Effects Seen in Visible Object Science has proved contradiction. Unless, of course, we know that contradiction is impossible, and that the law of non-contradiction was used in the process of "proving" contradiction, making it a self-defeating argument. Now, any rational person will know that nothing can be and not be at the same time, so this whole thing is absurd on its face, unless you take it to mean both are happening in some kind of figurative, unreal sense, in which case the article is luridly, and I suspect purposefully, misleading. Take away the breaking of the law of non-contradiction. These things are unknowable until they actually occur, yet follow laws of probability? Just thought I would be polemical and challenge the smug consensus here.

Ten Wedding Vows Based on Relationship Science | Samantha Joel I study romantic relationships. I'm also engaged. So, of course, I've given a tremendous amount of thought as to what it really means for my partner and I to marry one another. No pressure. Conveniently, I had decades of research at my fingertips to help us figure out what it really means to be a good spouse. Below are the ten promises that we've decided to make to each other. 1. Research on positive illusions shows that it's helpful to see romantic partners in a positive light -- to appreciate their positive qualities rather than ruminating about their flaws. In the second part of this vow, my partner and I are promising to support each other's attempts to grow and improve ourselves over time. 2. This vow draws from research on autonomy. 3. This vow draws from research on responsiveness, which involves sensitively meeting your partner's needs. 4. Once we figure out what each other's needs are, my partner and I promise that we will try our best to meet those needs. 5. 6. 7. 8. 9. 10.

Henri Becquerel Antoine Henri Becquerel (15 December 1852 – 25 August 1908) was a French physicist, Nobel laureate, and the discoverer of radioactivity along with Marie Skłodowska-Curie and Pierre Curie,[1] for which all three won the 1903 Nobel Prize in Physics. Biography[edit] Early life[edit] Becquerel was born in Paris into a family which produced four generations of scientists: Becquerel's grandfather (Antoine César Becquerel), father (Alexandre-Edmond Becquerel), and son (Jean Becquerel). Career[edit] In 1892, he became the third in his family to occupy the physics chair at the Muséum National d'Histoire Naturelle. Becquerel's earliest works centered around the subject of his doctoral thesis: the plane polarization of light, with the phenomenon of phosphorescence and absorption of light by crystals.[2] Becquerel's discovery of spontaneous radioactivity is a famous example of serendipity, of how chance favors the prepared mind. Becquerel in the lab Honors and awards[edit] See also[edit] References[edit]

Bell's theorem Bell's theorem is a no-go theorem famous for drawing an important distinction between quantum mechanics (QM) and the world as described by classical mechanics. In its simplest form, Bell's theorem states:[1] No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics. In the early 1930s, the philosophical implications of the current interpretations of quantum theory were troubling to many prominent physicists of the day, including Albert Einstein. In a well-known 1935 paper, Einstein and co-authors Boris Podolsky and Nathan Rosen (collectively "EPR") demonstrated by a paradox that QM was incomplete. This provided hope that a more-complete (and less-troubling) theory might one day be discovered. In the 1950s, antecedent probabilistic theorems were published by Jean Bass, Emil D. These three key concepts – locality, realism, freedom – are highly technical and much debated. Overview[edit] , local realism predicts or less. Bell inequalities[edit]

Dear Marijuana Relephant bonus: a Brief History of Weed. And, Pot as Spiritual Tool? Hi. It’s me, Alexandra. I know I’ve been distant lately. I’m 26. I love you. What’s one lost fan, right? I need you to know these things that I’ve come to understand about you and about myself when we hang out. I’m sure that every day, boatloads of people realize what I’m about to say. I know that you heal. It’s cheating myself and the road that I have to walk through life—through pain, foolishness, discomfort and the work I need to do on that tendency toward not-always-healthy escapism I harbor. They will forever stay with me. They are indestructible and hold a solid foundation for my appreciation of humanity, art, love, peace, tolerance and happiness. Can you blame me? You’re awesomely physically intoxicating. Indeed, you’ve enriched my prose and artistry. Now, these great depths weren’t plundered or arrived to every time—sometimes you just helped the room vibe. We would all gather around you. You’ve got integrity. Every.

J. J. Thomson In 1897 Thomson showed that cathode rays were composed of a previously unknown negatively charged particle, and thus he is credited with the discovery and identification of the electron; and, in a broader sense, with the discovery of the first subatomic particle. Thomson is also credited with finding the first evidence for isotopes of a stable (non-radioactive) element in 1913, as part of his exploration into the composition of canal rays (positive ions). He invented the mass spectrometer. Thomson was awarded the 1906 Nobel Prize in Physics for the discovery of the electron and for his work on the conduction of electricity in gases. Biography[edit] Joseph John Thomson was born in 1856 in Cheetham Hill, Manchester, England. His early education was in small private schools where he demonstrated great talent and interest in science. Thomson was elected a Fellow of the Royal Society[1] on 12 June 1884 and was President of the Royal Society from 1915 to 1920. Career[edit] Other work[edit]

Personal and Historical Perspectives of Hans Bethe Stumblers Who Like 201 Ways to Arouse Your Creativity Arouse your creativity Electric flesh-arrows … traversing the body. A rainbow of color strikes the eyelids. Creativity is like sex. I know, I know. The people I speak of are writers. Below, I’ve exposed some of their secret tips, methods, and techniques. Now, lie back, relax and take pleasure in these 201 provocative ways to arouse your creativity. Great hacks from Merlin Mann of 43 Folders Electron History[edit] In the early 1700s, Francis Hauksbee and French chemist Charles François de Fay independently discovered what they believed were two kinds of frictional electricity—one generated from rubbing glass, the other from rubbing resin. From this, Du Fay theorized that electricity consists of two electrical fluids, vitreous and resinous, that are separated by friction, and that neutralize each other when combined.[17] A decade later Benjamin Franklin proposed that electricity was not from different types of electrical fluid, but the same electrical fluid under different pressures. He gave them the modern charge nomenclature of positive and negative respectively.[18] Franklin thought of the charge carrier as being positive, but he did not correctly identify which situation was a surplus of the charge carrier, and which situation was a deficit.[19] Discovery[edit] A beam of electrons deflected in a circle by a magnetic field[25] Robert Millikan Atomic theory[edit]

Quantum Mechanics! - First Quantum Effects Seen in Visible Object