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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).

Play framework - Home 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

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.

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.

Physicists Slow Speed of Light Physicists Slow Speed of Light By William J. Cromie Gazette Staff Light, which normally travels the 240,000 miles from the Moon to Earth in less than two seconds, has been slowed to the speed of a minivan in rush-hour traffic -- 38 miles an hour. An entirely new state of matter, first observed four years ago, has made this possible. Such an exotic medium can be engineered to slow a light beam 20 million-fold from 186,282 miles a second to a pokey 38 miles an hour. "In this odd state of matter, light takes on a more human dimension; you can almost touch it," says Lene Hau, a Harvard University physicist. Hau led a team of scientists who did this experiment at the Rowland Institute for Science, a private, nonprofit research facility in Cambridge, Mass., endowed by Edwin Land, the inventor of instant photography. In the future, slowing light could have a number of practical consequences, including the potential to send data, sound, and pictures in less space and with less power.

11.19.2007 - New technique captures chemical reactions in a single living... UC Berkeley Press Release New technique captures chemical reactions in a single living cell for the first time By Sarah Yang, Media Relations | 19 November 2007 BERKELEY – Bioengineers at the University of California, Berkeley, have discovered a technique that for the first time enables the detection of biomolecules' dynamic reactions in a single living cell. By taking advantage of the signature frequency by which organic and inorganic molecules absorb light, the team of researchers, led by Luke Lee, professor of bioengineering and director of UC Berkeley's Biomolecular Nanotechnology Center, can determine in real time whether specific enzymes are activated or particular genes are expressed, all with unprecedented resolution within a single living cell. The technique, described in the Nov. 18 issue of the journal Nature Methods, could lead to a new era in molecular imaging with implications for cell-based drug discovery and biomedical diagnostics.

The Complexity and Artificial Life Research Concept for Self-Organizing Systems Why the Big Bang is Wrong undefined John Kierein The Big Bang theory of the universe is wrong because the cosmological red shift is due to the Compton effect rather than the Doppler effect. See The Endless, Boundless, Stable Universe by Grote Reber and Hubble's Constant in Terms of the Compton Effect by John Kierein. The latter describes how the Compton effect cosmological red shift accelerates with increasing distance. Reber showed that the Compton effect was the cause of the red shift in order to explain the observations of bright, very long wavelength, extragalactic radio waves. Quasars may be much closer than their red shift would indicate if they have an "intrinsic" red shift due to being surrounded by a 'fuzzy' atmosphere containing free electrons and other material. Some such quasars may be double stars, with one member being an ordinary star and the other exhibiting a large red shift and being labeled as a quasar. The red shift on the sun is obviously not Doppler since the sun is not moving away from us.

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