Interpretations of quantum mechanics An interpretation of quantum mechanics is a set of statements which attempt to explain how quantum mechanics informs our understanding of nature. Although quantum mechanics has held up to rigorous and thorough experimental testing, many of these experiments are open to different interpretations. There exist a number of contending schools of thought, differing over whether quantum mechanics can be understood to be deterministic, which elements of quantum mechanics can be considered "real", and other matters. This question is of special interest to philosophers of physics, as physicists continue to show a strong interest in the subject. History of interpretations[edit] Main quantum mechanics interpreters An early interpretation has acquired the label Copenhagen interpretation, and is often used. Nature of interpretation[edit] An interpretation of quantum mechanics is a conceptual or argumentative way of relating between: Two qualities vary among interpretations: Concerns of Einstein[edit]
Winter Temperatures and the Arctic Oscillation If you live nearly anywhere in North America, Europe, or Asia, it’s no news that December 2009 and early January 2010 were cold. This image illustrates how cold December was compared to the average of temperatures recorded in December between 2000 and 2008. Blue points to colder than average land surface temperatures, while red indicates warmer temperatures. Much of the Northern Hemisphere experienced cold land surface temperatures, but the Arctic was exceptionally warm. This weather pattern is a tale-tell sign of the Arctic Oscillation. The Arctic Oscillation is a climate pattern that influences winter weather in the Northern Hemisphere. Throughout December 2009, the North Atlantic Oscillation was strongly negative, said the National Weather Service. ReferencesClimate Prediction Center. (2010, January 8). NASA Earth Observatory image by Kevin Ward, based on data provided by the NASA Earth Observations (NEO) Project. Instrument(s): Terra - MODIS
DNA molecules can 'teleport', Nobel Prize winner claims A Nobel Prize winning biologist has ignited controversy after publishing details of an experiment in which a fragment of DNA appeared to ‘teleport’ or imprint itself between test tubes. According to a team headed by Luc Montagnier, previously known for his work on HIV and AIDS, two test tubes, one of which contained a tiny piece of bacterial DNA, the other pure water, were surrounded by a weak electromagnetic field of 7Hz. Eighteen hours later, after DNA amplification using a polymerase chain reaction, as if by magic the DNA was detectable in the test tube containing pure water. Oddly, the original DNA sample had to be diluted many times over for the experiment to work, which might explain why the phenomenon has not been detected before, assuming that this is what has happened. The phenomenon might be very loosely described as 'teleportation' except that the bases project or imprint themselves across space rather than simply moving from one place to another. What does all of this mean?
EPR paradox Albert Einstein The EPR paradox is an early and influential critique leveled against the Copenhagen interpretation of quantum mechanics. Albert Einstein and his colleagues Boris Podolsky and Nathan Rosen (known collectively as EPR) designed a thought experiment which revealed that the accepted formulation of quantum mechanics had a consequence which had not previously been noticed, but which looked unreasonable at the time. The scenario described involved the phenomenon that is now known as quantum entanglement. According to quantum mechanics, under some conditions, a pair of quantum systems may be described by a single wave function, which encodes the probabilities of the outcomes of experiments that may be performed on the two systems, whether jointly or individually. At the time the EPR article discussed below was written, it was known from experiments that the outcome of an experiment sometimes cannot be uniquely predicted. History of EPR developments[edit] Einstein's opposition[edit]
Cell Size and Scale Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification. Smaller cells are easily visible under a light microscope. To see anything smaller than 500 nm, you will need an electron microscope. Adenine The label on the nucleotide is not quite accurate. How can an X chromosome be nearly as big as the head of the sperm cell? No, this isn't a mistake. The X chromosome is shown here in a condensed state, as it would appear in a cell that's going through mitosis. A chromosome is made up of genetic material (one long piece of DNA) wrapped around structural support proteins (histones). Carbon The size of the carbon atom is based on its van der Waals radius.
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. The Planck relation now describes the energy of each photon in terms of the photon's frequency. This energy is extremely small in terms of ordinary experience. Since the frequency , wavelength λ, and speed of light c are related by λν = c, the Planck relation for a photon can also be expressed as The above equation leads to another relationship involving the Planck constant. Value[edit] Significance of the value[edit]
Applications Illiesia An open letter written by Henry Hagedom in March 2001, to the academic community that calls for change in academic publishing. A Call for Change in Academic Publishing Open Letter: I have resigned as Editor of Archives to start an online journal for insect biology produced in collaboration with the Library of The University of Arizona. The new journal has the potential to change the way we share information in our discipline. Below you will find a detailed explanation of my motivation for starting the new journal and some details of the journal as well. I resigned because I strongly feel that commercial publishers are ripping academic scholars off. Why has Archives increased the cost of an institutional subscription by nearly an order of magnitude since 1986 without an equivalent increase in the number of papers published? The price increase for Archives is not an isolated case. The Faustian bargain: your copyright for tenure A New On-line Journal: A Collaborative Project with the Library
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). According to the Intergovernmental Panel on Climate Change, CO2 is the most important driver of global warming. NASA is about to launch a spacecraft to keep track of this greenhouse gas. A new ScienceCast video explores the goals and underlying technology of the Orbiting Carbon Observatory. Also known as “OCO-2″, the polar orbiting satellite will provide a global picture of human and natural sources of carbon dioxide. Although the mission is named OCO two, it is actually NASA’s first spacecraft dedicated to measuring atmospheric carbon dioxide levels. It’s coming just in time. Source: Dr.
Matrix mechanics Matrix mechanics is a formulation of quantum mechanics created by Werner Heisenberg, Max Born, and Pascual Jordan in 1925. In some contrast to the wave formulation, it produces spectra of energy operators by purely algebraic, ladder operator, methods.[1] Relying on these methods, Pauli derived the hydrogen atom spectrum in 1926,[2] before the development of wave mechanics. Development of matrix mechanics[edit] In 1925, Werner Heisenberg, Max Born, and Pascual Jordan formulated the matrix mechanics representation of quantum mechanics. Epiphany at Helgoland[edit] In 1925 Werner Heisenberg was working in Göttingen on the problem of calculating the spectral lines of hydrogen. "It was about three o' clock at night when the final result of the calculation lay before me. The Three Fundamental Papers[edit] After Heisenberg returned to Göttingen, he showed Wolfgang Pauli his calculations, commenting at one point:[4] In the paper, Heisenberg formulated quantum theory without sharp electron orbits. W.
BEN FRANKLIN SHOULD HAVE SAID ELECTRONS ARE POSITIVE BEN FRANKLIN SHOULD HAVE SAID ELECTRONS ARE POSITIVE? --- Wrong. Many authors bemoan the fact that Ben Franklin labeled "resinous electricity" as negative, and "vitreous electricity" as positive. By choosing the polarities this way, forces us to say that electrons carry a charge of negative electricity. As a result, we must name the electric currents in metals as flows of NEGATIVE charge rather than positive charge. Did make a mistake? If had instead chosen the electrons to be positive, then we could more easily avoid confronting the real problem. The solution isn't just to ignore our discomfort and pretend that we understand electricity. 1. 2. 3. 4. 5. 6. 7. These seven statements are wrong. Notice the problem. Here are the corrections for the above seven mistakes: 1. 2. 3. 4. 5. are near each other, their charges cancel. 6. 7. Also plasmas can have positive electric currents as well as negative: for example neon signs, fluorescent lights, camera flashes, and sparks of all kinds. 8.