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Quantum Physics Revealed As Non-Mysterious

Quantum Physics Revealed As Non-Mysterious
This is one of several shortened indices into the Quantum Physics Sequence. Hello! You may have been directed to this page because you said something along the lines of "Quantum physics shows that reality doesn't exist apart from our observation of it," or "Science has disproved the idea of an objective reality," or even just "Quantum physics is one of the great mysteries of modern science; no one understands how it works." There was a time, roughly the first half-century after quantum physics was invented, when this was more or less true. Certainly, when quantum physics was just being discovered, scientists were very confused indeed! But time passed, and science moved on. The series of posts indexed below will show you - not just tell you - what's really going on down there. Some optional preliminaries you might want to read: Reductionism: We build models of the universe that have many different levels of description. And here's the main sequence:

http://lesswrong.com/lw/r7/quantum_physics_revealed_as_nonmysterious/

Related:  Quantum MechanicsrisullyQUANTUM PHYSICS 2

X 4, 041013 (2014) - Quantum Phenomena Modeled by Interactions between Many Classical Worlds We investigate whether quantum theory can be understood as the continuum limit of a mechanical theory, in which there is a huge, but finite, number of classical “worlds,” and quantum effects arise solely from a universal interaction between these worlds, without reference to any wave function. Here, a “world” means an entire universe with well-defined properties, determined by the classical configuration of its particles and fields. In our approach, each world evolves deterministically, probabilities arise due to ignorance as to which world a given observer occupies, and we argue that in the limit of infinitely many worlds the wave function can be recovered (as a secondary object) from the motion of these worlds.

Finite potential well The finite potential well (also known as the finite square well) is a concept from quantum mechanics. It is an extension of the infinite potential well, in which a particle is confined to a box, but one which has finite potential walls. Unlike the infinite potential well, there is a probability associated with the particle being found outside the box. The quantum mechanical interpretation is unlike the classical interpretation, where if the total energy of the particle is less than potential energy barrier of the walls it cannot be found outside the box.

Planck constant Plaque at the Humboldt University of Berlin: "Max Planck, discoverer of the elementary quantum of action h, taught in this building from 1889 to 1928." In 1905 the value (E), the energy of a charged atomic oscillator, was theoretically associated with the energy of the electromagnetic wave itself, representing the minimum amount of energy required to form an electromagnetic field (a "quantum"). Further investigation of quanta revealed behaviour associated with an independent unit ("particle") as opposed to an electromagnetic wave and was eventually given the term photon.

Quantum Chaos Editor's Note: This feature was originally published in our January 1992 issue. We are posting it because of recent discussions of the connections between chaos and quantum mechanics. In 1917 Albert Einstein wrote a paper that was completely ignored for 40 years.

Particle in a box In quantum mechanics, the particle in a box model (also known as the infinite potential well or the infinite square well) describes a particle free to move in a small space surrounded by impenetrable barriers. The model is mainly used as a hypothetical example to illustrate the differences between classical and quantum systems. In classical systems, for example a ball trapped inside a large box, the particle can move at any speed within the box and it is no more likely to be found at one position than another. However, when the well becomes very narrow (on the scale of a few nanometers), quantum effects become important.

NASA to Launch Spacecraft to Keep Track of Global Carbon Dioxide - SciTech Daily NASA is about to launch the Orbiting Carbon Observatory – a satellite dedicated to the study of global carbon dioxide sources that will help researchers predict the future of climate change. In the lexicon of climate change, one word appears more often than any other: “carbon.” Carbon credits, carbon emissions, carbon sequestration…. These terms are on everyone’s lips. The reason is carbon dioxide (CO2). Susskind Lectures Listed below are the (current) set of courses on theoretical physics courtesy of Stanford University. The lecturer is Professor Leonard Susskind, an eminent theoretical physicist and one of the founding fathers of string theory. A profile of Professor Susskind is available on Wikipedia. These lectures can be considered to be - and are sometimes referred to as - the Theoretical Minimum, meaning that the material covered in each course is the minimum that could be taught in order to define and use key concepts of modern physics. I suppose it would be possible to complete some of these courses without a good mathematical grounding, but I imagine a reasonable knowledge of algebra, geometry and calculus is pretty much required to understand most of the lectures. Professor Susskind also assumes a knowledge of Newton's laws of motion.

Solution of Schrödinger equation for a step potential In quantum mechanics and scattering theory, the one-dimensional step potential is an idealized system used to model incident, reflected and transmitted matter waves. The problem consists of solving the time-independent Schrödinger equation for a particle with a step-like potential in one dimension. Typically, the potential is modelled as a Heaviside step function. Calculation[edit] Schrödinger equation and potential function[edit] New NASA/NOAA Animations Reveal Water Vapor Over Oceans - SciTech Daily The movement of upper-air water vapor over the Eastern Pacific is shown using GOES satellite air temperature data. High, cold clouds are white. High, cold, clear air (around -28 F) is blue. Lower, warmer, dry air (around -10 F) is magenta (where clear, dry air penetrates lower in the atmosphere). Image Credit: NASA/NOAA GOES Project Dennis Chesters Scientists have used observations from the National Oceanic and Atmospheric Administration’s Geostationary Operational Environmental Satellites to create two new types of animations that indicate where water vapor is moving over the Atlantic and Eastern Pacific oceans.

ETH - Quantum Information Theory Lecturer: Prof. Renato Renner Tuesday, 09:50-10:35, HIL D 60.1 Thursday, 13:45-15:30, HIT K 51 Macroscopic quantum phenomena Quantum mechanics is most often used to describe matter on the scale of molecules, atoms, or elementary particles. However some phenomena, particularly at low temperatures, show quantum behavior on a macroscopic scale. The best-known examples of macroscopic quantum phenomena are superfluidity and superconductivity; another example is the quantum Hall effect. Since 2000 there has been extensive experimental work on quantum gases, particularly Bose–Einstein Condensates.

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