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Uncertainty principle

Uncertainty principle
where ħ is the reduced Planck constant. The original heuristic argument that such a limit should exist was given by Heisenberg, after whom it is sometimes named the Heisenberg principle. This ascribes the uncertainty in the measurable quantities to the jolt-like disturbance triggered by the act of observation. Though widely repeated in textbooks, this physical argument is now known to be fundamentally misleading.[4][5] While the act of measurement does lead to uncertainty, the loss of precision is less than that predicted by Heisenberg's argument; the formal mathematical result remains valid, however. Since the uncertainty principle is such a basic result in quantum mechanics, typical experiments in quantum mechanics routinely observe aspects of it. Introduction[edit] Click to see animation. The superposition of several plane waves to form a wave packet. As a principle, Heisenberg's uncertainty relationship must be something that is in accord with all experience. . with yields where

The Infinity of Quantum Physics Quantum Mechanics the Infinity Photon Electron Couplings creating sets of infinities of Fractal Self-Similarities Atom surround by Photon Electron Coupling. Expanding as a Wave-Particle Function of future possibilities. Wave-Particle Function collapsing into sets of Fractal Self-Similarities expanding as set of infinities creating there own Spacetime. Infinity can always be divided up into ever increasing sets of infinities because of the continuous expansion at the quantum level.

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). 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] Thomas Young's sketch of two-slit diffraction of waves, 1803 Particle impacts make visible the interference pattern of waves. A quantum particle is represented by a wave packet.

Quantum mechanics Description of physical properties at the atomic and subatomic scale Quantum mechanics is a fundamental theory in physics that describes the behavior of nature at and below the scale of atoms.[2]: 1.1 It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science. Classical physics, the collection of theories that existed before the advent of quantum mechanics, describes many aspects of nature at an ordinary (macroscopic) scale, but is not sufficient for describing them at small (atomic and subatomic) scales. Quantum mechanics arose gradually from theories to explain observations that could not be reconciled with classical physics, such as Max Planck's solution in 1900 to the black-body radiation problem, and the correspondence between energy and frequency in Albert Einstein's 1905 paper, which explained the photoelectric effect. Overview and fundamental concepts Mathematical formulation . and , where Here .

Complementarity (physics) In physics, complementarity is a fundamental principle of quantum mechanics, closely associated with the Copenhagen interpretation. It holds that objects governed by quantum mechanics, when measured, give results that depend inherently upon the type of measuring device used, and must necessarily be described in classical mechanical terms. Further, a full description of a particular type of phenomenon can only be achieved through measurements made in each of the various possible bases — which are thus complementary. The complementarity principle was formulated by Niels Bohr, the developer of the Bohr model of the atom, and a leading founder of quantum mechanics.[1] Bohr summarized the principle as follows: ...however far the [quantum physical] phenomena transcend the scope of classical physical explanation, the account of all evidence must be expressed in classical terms. For example, the particle and wave aspects of physical objects are such complementary phenomena. Physicists F.A.M. Dr.

8 shocking things we learned from Stephen Hawking's book From the idea that our universe is one among many, to the revelation that mathematician Pythagoras didn't actually invent the Pythagorean theorem, here are eight shocking things we learned from reading physicist Stephen Hawking's new book, "The Grand Design," written with fellow physicist Leonard Mlodinow of Caltech. The book, covering major questions about the nature and origin of the universe, was released Sept. 7 by its publisher, Bantam. 1. For example, if all we know is that a particle traveled from point A to point B, then it is not true that the particle took a definite path and we just don't know what it is. Yeah, we're still trying to wrap our brains around this. The authors sum up: "No matter how thorough our observation of the present, the (unobserved) past, like the future, is indefinite and exists only as a spectrum of possibilities." 2. This fun fact: A 1-watt night-light emits a billion billion photons each second. Photons are the little packets that light comes in. 3. 4. 5.

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]

Physicists challenge classical world with quantum-mechanical implementation of 'shell game' Inspired by the popular confidence trick known as "shell game," researchers at UC Santa Barbara have demonstrated the ability to hide and shuffle "quantum-mechanical peas" -- microwave single photons -- under and between three microwave resonators, or "quantized shells." In a paper published in the Jan. 30 issue of the journal Nature Physics, UCSB researchers show the first demonstration of the coherent control of a multi-resonator architecture. This topic has been a holy grail among physicists studying photons at the quantum-mechanical level for more than a decade. The UCSB researchers are Matteo Mariantoni, postdoctoral fellow in the Department of Physics; Haohua Wang, postdoctoral fellow in physics; John Martinis, professor of physics; and Andrew Cleland, professor of physics. According to the paper, the "shell man," the researcher, makes use of two superconducting quantum bits (qubits) to move the photons -- particles of light -- between the resonators.

Quantum superposition Quantum superposition is a fundamental principle of quantum mechanics that holds that a physical system—such as an electron—exists partly in all its particular theoretically possible states (or, configuration of its properties) simultaneously; but when measured or observed, it gives a result corresponding to only one of the possible configurations (as described in interpretation of quantum mechanics). and . Here is the Dirac notation for the quantum state that will always give the result 0 when converted to classical logic by a measurement. is the state that will always convert to 1. Concept[edit] The principle of quantum superposition states that if a physical system may be in one of many configurations—arrangements of particles or fields—then the most general state is a combination of all of these possibilities, where the amount in each configuration is specified by a complex number. For example, if there are two configurations labelled by 0 and 1, the most general state would be . . . .

SCHOPENHAUER'S 38 STRATAGEMS, OR 38 WAYS TO WIN AN ARGUMENT Arthur Schopenhauer (1788-1860), was a brilliant German philosopher. These 38 Stratagems are excerpts from "The Art of Controversy", first translated into English and published in 1896. Carry your opponent's proposition beyond its natural limits; exaggerate it. The more general your opponent's statement becomes, the more objections you can find against it. The more restricted and narrow his or her propositions remain, the easier they are to defend by him or her. (abstracted from the book:Numerical Lists You Never Knew or Once Knew and Probably Forget, by: John Boswell and Dan Starer) Measurement in quantum mechanics A measurement always causes the system to jump into an eigenstate of the dynamical variable that is being measured, the eigenvalue of this eigenstate belongs to being equal to the result of the measurement— P.A.M. Dirac (1958) in "The Principles of Quantum Mechanics" p. 36 The framework of quantum mechanics requires a careful definition of measurement. The issue of measurement lies at the heart of the problem of the interpretation of quantum mechanics, for which there is currently no consensus. Measurement from a practical point of view[edit] Measurement plays an important role in quantum mechanics, and it is viewed in different ways among various interpretations of quantum mechanics. Qualitative overview[edit] In classical mechanics, a simple system consisting of only one single particle is fully described by the position and momentum The measurement process is often considered as random and indeterministic. Quantitative details[edit] Measurable quantities ("observables") as operators[edit]

Will you perceive the event that kills you? David Eagleman is guest blogging this week. When light strikes your eyes, it takes some hundreds of milliseconds before you become conscious of the event. As a consequence, you are always living in the past. This strange fact of our existence is well known is neuroscience, but there’s an interesting, underappreciated consequence: you may not ever become aware of the thing that kills you. Cormac McCarthy addresses this point in his post-apocalyptic novel The Road, in a scene in which the main character has his pistol leveled on a miscreant. The protagonist replies, “Yes they will. “How do you figure that?” “Because the bullet travels faster than sound. One way to appreciate the slowness of your perception is to compare it to the speed of mechanical devices. 15 ms - Roof begins to absorb part of the impact. The last line is the zinger. David Eagleman is a neuroscientist and a writer.

Pauli exclusion principle A more rigorous statement is that the total wave function for two identical fermions is anti-symmetric with respect to exchange of the particles. This means that the wave function changes its sign if the space and spin co-ordinates of any two particles are interchanged. Integer spin particles, 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] "Half-integer spin" means that the intrinsic angular momentum value of fermions is (reduced Planck's constant) times a half-integer (1/2, 3/2, 5/2, etc.). History[edit] In the early 20th century it became evident that atoms and molecules with even numbers of electrons are more chemically stable than those with odd numbers of electrons. Pauli looked for an explanation for these numbers, which were at first only empirical. Connection to quantum state symmetry[edit] and the other in state

Nanotube yarn makes self-cleaning clothes that are also batteries By turning powders into fibers using carbon nanotube webs, researchers at the University of Texas have managed to make yarn that can clean itself and work as a battery. It also happens to be a superconductor, but most importantly, it's machine-washable. You may not think about it, but a lot of the cool technologies that we depend on every day rely on powders to work. Lithium ion batteries, for example, use a fine powder with a huge surface area as an electrode to store energy. One way to get around this problem is to use nanotubes, those magical carbon structures that are capable of just about anything. The upshot of this technique is that you can make yourself a piece of fabric that is, for all intents and purposes, one giant battery. Technology Review, via Inhabitat

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