121. Molecular Quantum Mechanics - Conference In Honor Of Nicholas Handy http://www.ccc.uga.edu/Handy/

122. Quantum Logic And Probability Theory How quantum mechanics can be regarded as a nonclassical probabilistic calculus; by Alexander Wilce. http://plato.stanford.edu/entries/qt-quantlog/

version history HOW TO CITE THIS ENTRY Stanford Encyclopedia of Philosophy A B C D ... Z This document uses XHTML-1/Unicode to format the display. Older browsers and/or operating systems may not display the formatting correctly. last substantive content change FEB Quantum Logic and Probability Theory At its core, quantum mechanics can be regarded as a non-classical probability calculus resting upon a non-classical propositional logic. More specifically, in quantum mechanics each probability-bearing proposition of the form "the value of physical quantity A lies in the range B " is represented by a projection operator on a Hilbert space H . These form a non-Boolean in particular, non-distributive orthocomplemented lattice. Quantum-mechanical states correspond exactly to probability measures (suitably defined) on this lattice. What are we to make of this? Some have argued that the empirical success of quantum mechanics calls for a revolution in logic itself. This view is associated with the demand for a realistic interpretation of quantum mechanics, i.e., one not grounded in any primitive notion of measurement. Against this, there is a long tradition of interpreting quantum mechanics operationally, that is, as being precisely a theory of measurement. On this latter view, it is not surprising that a "logic" of measurement-outcomes, in a setting where not all measurements are compatible, should prove not to be Boolean. Rather, the mystery is why it should have the particular non-Boolean structure that it does in quantum mechanics. A substantial literature has grown up around the programme of giving some independent motivation for this structure ideally, by deriving it from more primitive and plausible axioms governing a generalized probability theory.

123. Schroedinger's Cat The Present Situation In quantum mechanics. Erwin Schroedinger. A translation 2. Statistics of Model Variables in quantum mechanics. At the http://www.emr.hibu.no/lars/eng/cat/Default.htm

The Present Situation In Quantum Mechanics Erwin Schroedinger A translation of Schroedingers "cat paradox" paper" Translator: John D. Trimmer This translation was originally published in Proceedings of the American Philosophical Society , 124, 323-38. [And then appeared as Section I.11 of Part I of Quantum Theory and Measurement (J.A. Wheeler and W.H. Zurek, eds., Princeton university Press, New Jersey 1983).] Contents Introductory Note 1. The Physics of Models 2. Statistics of Model Variables in Quantum Mechanics 3. Examples of Probability Predictions ... Notes Introductory Note This is a translation of Schro:dinger's three-part 1935 paper in Die Naturwissenschaften . Earlier that same year there had appeared the Einstein, Podolsky, Rosen paper (also famous in "paradoxology") which, Schro:dinger says, in a footnote, motivated his offering. Along with this article in German, Schro:dinger had two closely-related English-language publications. But the German, aside from its one-paragraph presentation of the famous cat, covers additional territory and gives many fascinating insights into Schro:dinger's thought. The translator's goal has been to adhere to the logical and physical content of the original, while at the same time trying to convey something of its semi-conversational, at times slightly sardonic flavor. TRANSLATION The Physics of Models In the second half of the previous century there arose, from the great progress in kinetic theory of gases and in the mechanical theory of heat, an ideal of the exact description of nature that stands out as the reward of centuries-long search and the fulfillment of millennia-long hope, and that is called classical. These are its features.

124. Exotic Probability Theories And Quantum Mechanics References Complex and negative probabilities and their relation to quantum mechanics http://physics.bu.edu/~youssef/quantum/quantum_refs.html

Exotic Probability Theories and Quantum Mechanics: References Dear Friends, I thought that it might be useful to collect references relevant to exotic probability theories and their relation to quantum mechanics. If you see something missing, please let me know. If you are new to this subject, there is no comprehensive review or introduction, but you might want to look at my talk from the 1995 Bayesian conference to get an idea of what this is all about. Regards, Saul Youssef A.V. Belinskii, How could you measure a negative probability? , JETP letters, 59, 301 (1994). D.J.Miller, Realism and Time Symmetry in Quantum Mechanics , Phys. Lett. A 1996. Ariel Caticha, Consistency and Linearity in Quantum Theory , Phys.Rev. A57, 1572 (1998). Ariel Caticha, Consistency, Amplitudes and Probabilities in Quantum Theory , preprint, 1998. Richard Feynman, Negative Probabilities , in Quantum Implications , eds B.J. Hiley and F.David Peat (Routledge and Kegan Paul, 1987). F.H.Frohner, The Riesz-Fejer Theorem: Missing Link between Probability Theory and Quantum Mechanics , Forschungszentrum Karlsruhe, FZKA 5888, May, 1997.

125. Schroedinger: "The Present Situation In Quantum Mechanics" THE PRESENT SITUATION IN quantum mechanics A TRANSLATION OF SCHRÖDINGER S CAT PARADOX PAPER . 2. Statistics of Model Variables in quantum mechanics. http://www.tu-harburg.de/rzt/rzt/it/QM/cat.html

THE PRESENT SITUATION IN QUANTUM MECHANICS: Translator: John D. Trimmer This translation was originally published in Proceedings of the American Philosophical Society , 124, 323-38. [And then appeared as Section I.11 of Part I of Quantum Theory and Measurement (J.A. Wheeler and W.H. Zurek, eds., Princeton university Press, New Jersey 1983).] Contents Introductory Note 1. The Physics of Models 2. Statistics of Model Variables in Quantum Mechanics 3. Examples of Probability Predictions ... Notes Introductory Note in Die Naturwissenschaften . Earlier that same year there had appeared the Einstein, Podolsky, Rosen paper TRANSLATION The Physics of Models In the second half of the previous century there arose, from the great progress in kinetic theory of gases and in the mechanical theory of heat, an ideal of the exact description of nature that stands out as the reward of centuries-long search and the fulfillment of millennia-long hope, and that is called classical. These are its features. Of natural objects, whose observed behavior one might treat, one set sup a representation - based on the experimental data in one's possession but without handcuffing the intuitive imagination - that is worked out in all details exactly

126. Volodymyr Krasnoholovets's Home Page Professor at the National Academy of Science, Kyiv. Contains description research in conventional, applied and fundamental physics. Also deals with the submicroscopic construction of nature, quantum mechanics is combined with gravity. http://www.inerton.kiev.ua/

127. Origins Of Quantum Mechanics This assumption was one of the postulates with which Bohr set up his atomic model which was later superceded by the true quantum mechanical model. http://itl.chem.ufl.edu/4412_aa/origins.html

The Hollow Chamber The hollow chamber is a good approximation of a black body. It has a tiny aperture through which radiation is emitted, and is immersed in a heat bath to keep it at constant temperature. The radiation emitted can be detected and analyzed with a spectrometer in order to obtain the spectral distribution of the emitted radiation energy. Spectral Distribution of the black body: The spectrum of the black body radiation is plotted for three different temperatures, 2000 K, 1750 K, and 1250 K. They appear as differently coloured solid curves with the radiation energy plotted as energy density per wavelength unit over wavelength (measured in nm). Stefan-Boltzmann's Law of black body radiation: The total emitted radiation energy of the black body at a given temperature, i.e. the integral, M, over the spectral distribution at each individual temperature setting, is proportional to the 4th power of T: with the constant Wien's Law of black body radiation: If the wavelength of maximum emission of the spectral distribution of the black body is plotted over 1/T, one obtains a straight line.

128. Codes For PHYCS 498A Codes for course by Richard M. Martin. http://www.physics.uiuc.edu/research/ElectronicStructure/498-s97/codes/code.html

Fortan Codes for PHYCS 498A The codes are written in FORTRAN 90, free format style. To compile them on an IBM workstation, use the command. Numerical Quadrature: simpn.f - Simpson's rule integration. simpe.f - Simpson's rule integration, refines grid until desired accuracy is obtained. inttest.f - Program to test these quaderature routines. Root finding: bisect.f - Bisection method root finder. hybrid.f - Hybrid bisection/secant root finder. roottest.f - Program to test these root finder routines. Semiclassical Quantization: semiclass.f - Main program and other code. simpe.f - Simpson's rule integration, refines grid until desired accuracy is obtained. hybrid.f - Hybrid bisection/secant root finder. sample input file sample output file All above codes in a tar-file: codes.tar Poison Equation solution by Green's function method poisson_mod.f - Module for solving the poisson equation. poissontest.f - Short program to run the poisson test. sample output file 1 - Expected output for poisson test. Solution of 1d Schrodinger equation by shooting method Source code: eigen_mod.f

129. Mysteries, Puzzles And Paradoxes In Quantum Mechanics - Garda 2003 Translate this page http://pandora.fisica.unimi.it/~garda2003/

130. Theory: Parity An overview of Parity in quantum mechanics and of the ways to break quantum mechanical symmetry. http://www2.slac.stanford.edu/vvc/theory/parity.html

Parity Many physics processes have a property known as parity invariance This means that the probability of a particle process occurring is exactly the same as the probability of the same process occurring with the position vectors and directions of travel of all particles reversed. What does it mean to reverse a position vector? Choose any point as your position vector origin and draw a line from the origin to the position of an object. That is the position vector of the object. A parity transformation about that origin would relocate the object at a point found by flipping that position vector so it goes the same distance from the origin but in exactly the opposite direction. It turns up to down, left to right, and front to back! This seems odd because we are used to thinking of up as physically very different from down, but if we reverse everything then the position of the earth changes, too. Consider, for example, a collision of two spheres in space. There would be no way you could tell by looking at a movie whether you were watching an actual collision or a parity reversed simulation of the collision, each would look equally plausible. Parity invariance is true for strong and electromagnetic interactions . This has many consequences for the possible outcomes in decays and scattering events One of the big surprises of the 1950s was the recognition that parity invariance is not true for weak interactions Right- and Left-Handed Particles

131. Basics Of Quantum Mechanics Basics of quantum mechanics. quantum mechanics is the Foundation of Chemistry quantum mechanics Explains the Structure of Atoms and Molecules. http://bouman.chem.georgetown.edu/atomorbs/qmbasics.html

HTTP 200 Document follows Date: Thu, 27 May 2004 04:22:31 GMT Server: NCSA/1.5.1 Content-type: text/html Basics of Quantum Mechanics Quantum Mechanics is the Foundation of Chemistry Quantum Mechanics Explains the Structure of Atoms and Molecules Quantum Mechanics Explains How Molecules React Quantum Mechanical Basis of Atomic Structure Go back to General Chemistry page Go back to de Dios' home page

132. Physics 232 Lecture Notes A set of online course notes for introductory physics. Includes electromagnetic fields, relativity, and quantum mechanics. http://www.pa.msu.edu/courses/1997spring/PHY232/lectures/

Lecture Notes by Topic Course information Coulomb's law Electric fields and electric potentials Gauss' law and conductors ... Cosmology and astrophysics These files are prepared not as a substitute for the text book, but instead as a substitute for lecture notes. Hopefully, one can then attend lecture and concentrate on the material rather than writing notes.

133. Quantum Mechanics Of Gaia Brain Gaia Brain is the biological model for politics and economics. We could build a better society if we each (or most of us, or a http://user.intersatx.net/jc/quantum.html

Gaia Brain ' is the biological model for politics and economics. We could build a better society if we each (or most of us, or a representative sample) express our feeling, our opinion about what limits we ought to place on human impacts on earth, (pollution, taking of resources, paving, etc.), and see to it that our democratic society produces a reality that respects the limits that the people define. If the average of all expressed opinions were taken as an overall limit of acceptable human impacts, then sale of permits to take resources or degrade natural resources, up to that limit, would put economic costs onto industries in proportion to how much natural resources they use. Industries would feel the ecological harm they do in their bottom line. They would have incentive to change their processes to reduce pollution and demands on resources. We would all have incentive to change our habits. As those things that are of marginal value to us but that have high ecological costs associated with their production increase in price, many of us will decide that they are not worth the higher price. We will stop buying those things. Injury to the earth, to the environment would be reduced. When our actions harm ecosystems or degrade environmental quality, we will get a signal, an economic price to pay, that deters us from performing those harmful actions to excess. This system of negative feedback would act as a sensory nervous system for earth, causing a reduction of injury or 'harm' to earth. Through the use of fees on the taking of resources and putting of pollution, we can bring actual impacts of human economic activity into accord with the expressed will of the people. This 'sensory nervous system for earth' emerges from nothing more nor less than direct

134. Mangled Worlds Quantum Mechanics When Worlds Collide Mangled Worlds quantum mechanics. by Robin Hanson, March 21, 2003. Robin Hanson, DriftDiffusion in Mangled Worlds quantum mechanics. http://hanson.gmu.edu/mangledworlds.html

When Worlds Collide: Mangled Worlds Quantum Mechanics by Robin Hanson , March 21, 2003. This variation on the many worlds interpretation of quantum mechanics allows us to derive the Born probability rule via finite world counting and no new physics. One of the deepest questions in physics is this: what exactly happens during a quantum measurement? Under the traditional (or "Copenhagen") view, quantum mechanics tells you how to calculate the probabilities of different measurement outcomes. You are to create a wave that describes your initial situation, and then have your wave evolve in time according to a certain linear deterministic rule until the time of a measurement. The equation that describes this rule is very much like the equations that govern the spread of waves over water, or of sound waves in the air. At the time of a measuremment you are to use the "Born rule" to convert your wave into probabilities of seeing different outcomes. This rule says to break your wave into compoments corresponding to each measurement outcome, and that the probability of each outcome is the measure (or size) of the corresponding component. After a measurement, you can again continue to evolve your wave via the linear deterministic rule, starting with the wave component corresponding to the outcome that was seen. The problem is, this procedure seems to say that during quantum measurements physical systems evolve according to a fundamentally different process. If, during a quantum measurement, you applied the usual wave propogation rule, instead of the Born probability rule, you would get a different answer. Now for generations students have been told not to worry about this, that the quantum wave doesn't describe what is really out there, but only what we know about what is out there. But when students ask what is really out there, they are told either that is one of the great mysteries of physics, or that such questions just do not make sense.

135. What Is Quantum Physics? History and explanation of quantum physics / quantum mechanics. http://www.jracademy.com/~jtucek/science/what.html

What is Quantum Physics? Does the thought of quantum physics send a chill down your spine, just like the words calculus, differential equations, and -gasp- organic chemistry? You may not even think that quantum physics is a serious science, like the more familiar Newtonian physics. Just relax! I'm sure you're comfortable with regular physics, which describes the way that matter interacts with other matter, i.e. gravity, velocity, etc. If not, maybe you should check out my regular Interactive Physics site. Anyway, quantum physics is just the physics of the incredibly small. While Newtonian physics can suitably describe the orbit of the planets or the energy transformations during a game of pool, quantum physics describes how electrons surround the nucleus of the atom and other subatomic actions. At this point, you may be thinking that there's not that big of a difference between these two sciences. Hey, both explain how matter interacts with other matter, so what's the big deal? The difference is that the common laws of physics begin to deteriorate on small scales. For example, Nippendenso (Japan Electric) built a car that's only half a millimeters long. One could easily mistake it for a grain of rice if not for its gold color. At the scale of 1 to 1000, physics is already changing. Oil would now gum up the engine, and the tires wouldn't have enough traction to move the car. I'm currently working on a list of quantum physics terms . It may or may not be done soon. "I think I can safely say that nobody understands quantum mechanics."

136. Physics Encyclopedia: Quantum Mechanics Nonrelativistic quantum mechanics. Physics Main Other Quantum Pages Help Suggest a Site Intro into quantum mechanics - an explanation by Todd. http://members.tripod.com/~IgorIvanov/physics/qm.html

var cm_role = "live" var cm_host = "tripod.lycos.com" var cm_taxid = "/memberembedded" Check out the NEW Hotbot Tell me when this page is updated Non-relativistic Quantum Mechanics Physics Main Other Quantum Pages Help Suggest a Site General QM resources Introductory Intro into Quantum Mechanics - an explanation by Todd Quantum Mechanics I - a comprehensive undergrad lecture course by N. Walet - from black body radiation up to 3D Scroedinger equation Problems in QM - 38 undergrad-level problems with solutions step-by-step Advanced topics Quantum Mechanics I from MIT - an extensive collection of lectures notes on different aspects of QM Black body radiation - from MIT Schroedinger equation and Mathematical methods in QM Introductory Time-development of quantum systems by Geza I. Mark - includes theoretical overview and demonstrations General features of Time-dependent and Time-independent Schoedinger equation Metastable States - 7 MPEG movies animating decays of and scattering on metastable states; from MIT Numerical solutions of Schrodinger equation - mpeg movies on several QM effects Angular Momentum in QM - a lecture course from Univ Birmingham Advanced topics Lectures on Perturbation Theory - 31pp, gifs of handwritten lectures from QM III course at MIT

137. Welcome To PhyCon Explains astrophysical concepts such as relativity, quantum mechanics, gravity, black holes, dark matter, quasars, macrocosmos and microcosmos. http://www.solnabrass.com/phycon/

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138. Quantum Mysteries If you understood this, you would understand quantum physics but as Feynman also said, nobody understands quantum mechanics (The Character of Physical Law http://www.biols.susx.ac.uk/home/John_Gribbin/quantum.htm

The experiment with two holes Faster than light Solving the mysteries Faster than light again ... Back to John Gribbin's Home Page Deepening the quantum mysterie s The "central mystery" of quantum physics just got more mysterious. Experimenters from the United States and Austria have got together to provide a new demonstration of how light going through a "double slit" experiment seems to know before it sets out in its journey exactly what kind of traps have been set for it along the way. This is a variation on the Young's slit experiment, familiar from school laboratory demonstrations of the wave nature of light. When a beam of monochromatic light is shone through two narrow holes in a screen, the light spreading out from the two holes interferes, just like ripples interfering on the surface of a pond, to produce a characteristic pattern on a second screen. The mystery is that light can also be described as a stream of particles, called photons. The light source in a Young's slit experiment can be turned down to the point where it consists of individual photons going through the experiment, one after the other. If the spots of light made by individual photons arriving at the second screen (actually a photoelectric detector) are added together, they still form an interference pattern, as if each photon goes through both holes and interferes with itself on the way through the experiment. It was Richard Feynman who described this as "the central mystery" of quantum theory, and then corrected himself, saying that in fact it is "the only mystery". If you understood this, you would understand quantum physics but as Feynman also said, "nobody understands quantum mechanics" (The Character of Physical Law, BBC Publications, 1965).

139. A Comp.ai.philosophy FAQ Overview and FAQ of web resources on Quantum Computing, Artificial Intelligence and Consciousness. http://www.dontveter.com/caipfaq/systems.html

http://www.dontveter.com , commercial use is prohibited. This material cannot be quoted at length or posted elsewhere on the net or included in CD ROM collections. Short quotations are permitted provided proper attribution is given. Algorithms and Hardware Most people interested in AI BELIEVE that a digital computer can do all that people can do if it is programmed correctly. Meaning that there are plenty of arguments over what the correct method of programming will turn out to be. Also meaning that some people doubt digital computers can do the job. Symbol Processing Symbol processing is the original dominant BELIEF of the AI community. Symbol processing requires the use of symbols, structures of symbols and rules. Symbols are defined as unique marks as on a piece of paper. Symbols can be equal or not equal but there are no other relations defined between them. Strictly speaking then, numbers are not allowed because numbers have an ordering to them, one unique number will be greater than or less than some other number. In practice symbol processing programs often incorporate the use of numbers so most "symbol processing" systems go beyond the processing of symbols. Implicitly they are saying that the statement, "symbol processing is necessary and sufficient for general intelligent action" is clearly false. They should go around saying that "symbol processing and numerical computing are necessary and sufficient for general intelligent action". But symbol processing believers go around saying "symbol processing is necessary and sufficient for general intelligent action" anyway.

140. Brief Review Of Quantum Chemistry Last Revised on 7 August 1997. Contents; The Motivation for quantum mechanics The Ultraviolet Catastrophe; The Photoelectric Effect; http://vergil.chemistry.gatech.edu/notes/quantrev/quantrev.html

Next: Contents Up: Quantum Chemistry Lecture Notes A Brief Review of Elementary Quantum Chemistry C. David Sherrill School of Chemistry and Biochemistry Georgia Institute of Technology Last Revised on 7 August 1997 Contents The Motivation for Quantum Mechanics The Ultraviolet Catastrophe The Photoelectric Effect ... About this document ... Links Go Quantum Physics C. David Sherrill

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