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List of unsolved problems in physics

List of unsolved problems in physics
Some of the major unsolved problems in physics are theoretical, meaning that existing theories seem incapable of explaining a certain observed phenomenon or experimental result. The others are experimental, meaning that there is a difficulty in creating an experiment to test a proposed theory or investigate a phenomenon in greater detail. Unsolved problems by subfield[edit] The following is a list of unsolved problems grouped into broad area of physics.[1] Cosmology, and general relativity[edit] Cosmic inflation Is the theory of cosmic inflation correct, and if so, what are the details of this epoch? Horizon problem Electroweak Horizon Problem Why aren't there obvious large-scale discontinuities in the electroweak vacuum, if distant parts of the observable universe were causally separate when the electroweak epoch ended? Future of the universe Is the universe heading towards a Big Freeze, a Big Rip, a Big Crunch or a Big Bounce? Gravitational wave Can gravitational waves be directly detected? .

Statistical Data Mining Tutorials Advertisment: In 2006 I joined Google. We are growing a Google Pittsburgh office on CMU's campus. We are hiring creative computer scientists who love programming, and Machine Learning is one the focus areas of the office. We're also currently accepting resumes for Fall 2008 intenships. If you might be interested, feel welcome to send me email: awm@google.com . The following links point to a set of tutorials on many aspects of statistical data mining, including the foundations of probability, the foundations of statistical data analysis, and most of the classic machine learning and data mining algorithms. These include classification algorithms such as decision trees, neural nets, Bayesian classifiers, Support Vector Machines and cased-based (aka non-parametric) learning. I hope they're useful (and please let me know if they are, or if you have suggestions or error-corrections).

Quantum entanglement: The missing link between wormholes? Wormholes — shortcuts that in theory can connect distant points in the universe — might be linked with the spooky phenomenon of quantum entanglement, where the behavior of particles can be connected regardless of distance, researchers say. These findings could help scientists explain the universe from its very smallest to its biggest scales. Scientists have long sought to develop a theory that can describe how the cosmos works in its entirety. Currently, researchers have two disparate theories, quantum mechanics and general relativity, which can respectively mostly explain the universe on its tiniest scales and its largest scales. There are currently several competing theories seeking to reconcile the pair. Intriguingly, quantum mechanics also has a phenomenon that can link objects such as electrons regardless of how far apart they are — quantum entanglement. Einstein derisively called this seemingly impossible connection "spooky action at a distance." Entanglement and wormholes

Play framework - Home Stream the Quantum Activist! The Quantum Activist is an internationally acclaimed documentary in distribution in 12 countries. You can now stream it through the internet to your laptop or tablet without any special systems required to watch instantly or later. A genuine paradigm shift. While mainstream science remains materialist, a substantial number of scientists are supporting and developing a paradigm based on the primacy of consciousness.Dr.

Amazing Scanning Electron Microscope Photos Amazing Scanning Electron Microscope Photos All these pictures are from the book 'Microcosmos,' created by Brandon Brill from London. This book includes many scanning electron microscope (SEM) images of insects, humanbody parts and household items. These are the most amazing images of what is too small tosee with the naked eye. 2-2-11 An ant, Formica fusca, holding a microchip Surface of an Erasable Programmable Read-Only Memory silicon microchip Eyelash hairs growing from the surface of human skin The surface of a strawberry Bacteria on the surface of a human tongue Human sperm (spermatozoa) Nylon hooks and loops of Velcro Household dust: includes long hairs of cat fur, twisted synthetic and woolen fibers, serrated insect scales, a pollen grain, and plant and insect remains The weave of nylon stocking fibers The head of a mosquito Head louse clinging to a human hair Eight eyes (two groups of four) on the head of a tarantula Cut human hairs and shaving foam between two razor blades Mushrooms spores

The Higgs Boson was found. Now what? Comstock/Thinkstock Images. On July 4, the physics community responded with jubilation to an announcement that had been anticipated for 50 years: the discovery of the Higgs Boson. Just as half of the country was ecstatic in 2008 when Barack Obama was first elected—supposedly heralding the end of “business as usual” in Washington—the Higgs breakthrough appeared to herald a new era in particle physics, one that could bring us closer to a possible unified theory describing all of the fundamental forces of nature. Unfortunately, in both cases, reality has intervened. Briefly, the Higgs is an elementary particle predicted 50 years ago during the development of the standard model of particle physics. Many might imagine that physicists were rooting for door No. 5 because we like to be vindicated. While the Higgs discovery was announced in July, the announcement was based on preliminary data.

Give Ps a chance - Stanford Medicine Magazine - Stanford University School... A Nobelist’s quest to open our eyes to the next DNA. It’s called Poly P By SPYROS ANDREOPOULOS For the past 15 years, Arthur Kornberg, MD, a Nobel Prize-winning biochemist at Stanford, has been deepening his relationship with one of biology’s wallflowers: a molecule he has nicknamed poly P. While most other biochemists ignore the omnipresent molecule (it shows up in every living cell on Earth) Kornberg, 89, can’t pull himself away. “It’s more important than I am,” he says, with a smile. It’s not just his love of a good biochemical mystery that keeps the emeritus professor working in the lab — though that’s certainly part of what drives him. Inorganic polyphosphate, the molecule Kornberg calls poly P, is older than the hills — literally. What exactly is poly P? Kornberg became fascinated by poly P in the 1950s. When Kornberg arrived at Stanford to lead the biochemistry department in the early ’60s, his work on DNA, for which he had received the Nobel Prize in 1959, had heated up.

Usenet Physics FAQ Version Date: August 2013 This list of answers to frequently asked questions in physics was created by Scott Chase in 1992. Its purpose was to provide good answers to questions that had been discussed often in the sci.physics and related Internet news groups. The articles in this FAQ are based on those discussions and on information from good reference sources. Most of the entries that you'll find here were written in the days when the Internet was brand new. So because of their age, the FAQ entries that you'll find here have a great deal of academic credibility—but they are not always perfect and complete. This document is copyright. General Physics Particle and Nuclear Physics Quantum Physics Relativity and Cosmology Speed of Light Special Relativity General Relativity and Cosmology Black Holes Reference Topics There are many other places where you may find answers to your question. This FAQ is currently available from these web sites: Australia:

Computer learns language by playing games Computers are great at treating words as data: Word-processing programs let you rearrange and format text however you like, and search engines can quickly find a word anywhere on the Web. But what would it mean for a computer to actually understand the meaning of a sentence written in ordinary English — or French, or Urdu, or Mandarin? One test might be whether the computer could analyze and follow a set of instructions for an unfamiliar task. And indeed, in the last few years, researchers at MIT’s Computer Science and Artificial Intelligence Lab have begun designing machine-learning systems that do exactly that, with surprisingly good results. Starting from scratch “Games are used as a test bed for artificial-intelligence techniques simply because of their complexity,” says Branavan, who was first author on both ACL papers. Moreover, Barzilay says, game manuals have “very open text. So initially, its behavior is almost totally random. Proof of concept

John Holland, Emergence The Bactra Review: Occasional and eclectic book reviews by Cosma Shalizi 46 From Chaos to Order by John Holland Addison-Wesley, 1997 Game Rules, or, Emergence according to Holland, or, Confessions of a Creative Reductionist John Holland was one of the world's first Ph.D.s in computer science, and even before that one of the first workers in machine learning. One of the things Holland has been thinking about for a long time is the puzzle of building blocks, of re-usable categorical parts. The problem of emergence is, roughly speaking --- and half the trouble with it is that everything we say about it is only rough --- the flip side of the problem of building blocks. Like almost all working scientists, Holland assumes that a valid explanation of (any one of) these puzzles is a reductionist one, one that explains the behavior or properties of the larger entity from those of its components and their interactions. Emergence is not so broad or ambitious as its title and publicity may suggest.

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