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Desde 1997 ajudando a ensinar e a divulgar a Física no Brasil
"Gente inteligente não gosta de coisa chata. É preciso mostrar coisas estimulantes. Desafiadoras. Não devemos conduzir nossos alunos para a passividade por obediência". (Prof. Luiz Carlos Menezes).
30% da economia mundial depende dos conhecimentos de Mecânica Quântica. O que você está fazendo aí parado? Vá estudar Quântica!
UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL ESCOLA DE ENGENHARIA DEPARTAMENTO DE ENGENHARIA NUCLEAR PESQUISA DE PÓS-GRADUAÇÃO: |
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ASTRONAUTICS Tale of the Damselfly by Evan Hadingham It was the world's first flight of a powered, heavier-than-air flying machine, or so everybody thought at the time. The date was November 12, 1906, and the setting was not the bleak sand dunes of Kitty Hawk, North Carolina, but the manicured gardens of the Bagatelle Park in the eastern suburbs of Paris. The elegantly attired aeronaut, Alberto Santos-Dumont, stood upright in his #14bis, an ungainly, tail-first contraption inspired by the box kite that he managed to coax into the air four times. His best flight was a powered hop lasting 21 seconds and covering 722 feet. The diminutive, daring Brazilian pioneer was hailed as the undisputed conqueror of the air. ASTRONAUTICS My First Balloon Ascent At the height of his career, the pioneering aviator Alberto Santos-Dumont believed that flight could be a pathway to world peace, enabling people to reflect on the all-too-human world below and inspiring them to lead more just and moral lives. But when he first took to the skies at the age of 24, flight for Santos was foremost an act of adventure and joy. In the following excerpt from his memoir My Airships, Santos reminisces about the virgin voyage he took in 1897. ASTRONAUTICS Russians begin preparation of Brazilian astronaut’s space flight Baikonur (Kazakhstan) – Ravil Khamitov, the Director of the Press Center of Baikonur, Russian cosmodrome located in Kazakhstan, said this Monday (27) that he considers "very meaningful that the first Brazilian cosmonaut will be launched to space exactly from the Yuri Gagarin platform." The Russian Gagarin was the first man to go to space, in 1961. ASTRONAUTICS Nine satellites ready for blast-off Nine satellites, including one that will carry nothing but seeds, are set to be launched into space this year. ASTRONAUTICS Shuttle hopes for three flights The US space agency (Nasa) is growing optimistic of resuming space shuttle flights in May and perhaps squeezing in three missions this year. ASTRONOMY The Nobel Prize in Physics goes to John C. Mather and George F. Smoot "for their discovery of the bl US space scientists John Mather and George Smoot were awarded the Nobel Physics Prize on Tuesday for a pioneering space mission which supports the "Big Bang" theory about the origins of the Universe. ASTRONOMY Cyclic universe could explain cosmological constant Two theoretical physicists have developed a model that could explain why the cosmological constant takes the small, positive value that it does in today's universe. The value of the constant is responsible for the observed acceleration in the expansion of the universe. However, the new model, developed by Paul Steinhardt of Princeton University in the US and Neil Turok at Cambridge University in the UK, will be controversial. It requires that time existed before the Big Bang, assumes that the universe is older than the 14 billion years we think it is, and says that the universe regularly undergoes repeating "cycles" of big bangs and big crunches (Sciencexpress 1126231). ASTRONOMY Pluto relegated to dwarf status Considered by many to be the ninth planet in the solar system, Pluto is now defined as a “dwarf planet” by the International Astronomical Union (IAU). The controversial decision was made yesterday and is based on the fact that Pluto’s orbital path overlaps with other objects such as asteroids and the planet Neptune. ASTRONOMY Gravity lens reveals dark matter US astronomers claim to have observed dark matter – the elusive substance that is believed to be five times as common as normal matter, accounting for nearly a quarter of the universe. ASTRONOMY The Final IAU Resolution on the definition of "planet" ready for voting Resolution 5A is the principal definition for the IAU usage of "planet" and related terms. Resolution 5B adds the word "classical" to the collective name of the eight planets Mercury through Neptune. ASTRONOMY Newfound Ice World Alters Perceptions of Planetary Systems Astronomers announced today the discovery of a frigid extrasolar planet several times larger than Earth orbiting a small red dwarf star roughly 9,000 light years away. ASTRONOMY NASA spacecraft finds water on Saturn moon It's almost 1300-million kilometres from earth, but scientists believe they have discovered evidence of water on one of Saturn's icy moons -- rekindling hope in the existence of life outside planet Earth. ASTRONOMY 'Laser star' enhances cosmic view The world's largest optical telescope facility can now use an "artificial star" to improve its vision. ASTRONOMY New type of star discovered Astronomers have found a new type of neutron star. The objects send out short bursts of radio waves lasting just two to 30 milliseconds followed by "dark spells" lasting minutes to hours. Conventional plusars, in contrast, emit flashes of radio waves at regular intervals. The new objects -- dubbed "rotating radio transients" or RRATs -- were discovered by a team led by Maura McLaughlin from the Jodrell Bank Observatory at the University of Manchester in the UK. She believes that the RRATs may outnumber conventional radio pulsars by a ratio of four to one (Nature 439 817). ASTRONOMY Three's company A team of astronomers in the US has confirmed the existence of two new moons orbiting around Pluto. The moons, dubbed rather prosaically P1 and P2, were initially detected by the Hubble Space Telescope last year and are the first objects to be discovered around the planet since its first moon, Charon, was found nearly 30 years ago. The moons are estimated to have diameters of between about 48 and 165 kilometres and are therefore much smaller than Charon, which is around 1200 km across. The discovery also makes Pluto the first Kuiper-belt object to have more than one satellite (Nature 439 943). COMPUTER SCIENCE Game physics starts to get real Part of the appeal of computer games is that they can take you places and show you things you would never find on Earth. COMPUTER SCIENCE Face Recognition Feature Readied For Japanese Cell Phones Vodafone's Face Sensing Engine uses a 3.2-megapixel camera to authenticate a user's facial features and eliminate the need for passwords or fingerprint verification. PHYSICS Scientists Express Skepticism Over Quantum Computer The science community takes a leery stance at D-Wave's quantum computer PHYSICS Quantum back-action has a cooling effect Researchers have developed a quantum electromechanical technique to exploit microscopic quantum effects on a macroscopic scale. The technique involves cooling a resonating beam of atoms by measuring its vibrations and could one day be used to cool nanoscale mechanical devices, say the researchers (Nature 443 193). PHYSICS Dirac medal for atomic physicist Peter Zoller of the University of Innsbruck has been awarded the 2006 Dirac medal of the International Centre for Theoretical Physics (ICTP) in Trieste, Italy. Zoller, the scientific director of the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences in Innsbruck, is honoured for his work in atomic physics, including proposing the use of trapped ions for quantum computing. The Dirac medal -- one of the world's most prestigious physics prizes -- is given each year on 8 August, the birth date of Paul Dirac. PHYSICS Mobile-phone network reveals the ties that bind If you and your best friend stop talking to each other after a massive row, you might think that would break up your entire social network. In fact, researchers studying the communication patterns of 4.6 million mobile-phone users suggest that your social circle is more likely to break into smaller clusters if you lose contact with more casual acquaintances (arXiv.org/physics/0610104). PHYSICS Physics in medicine Fundamental breakthroughs in physics are continuing to yield new medical technologies for identifying and treating a range of diseases. PHYSICS How particles can be therapeutic Until a cure for cancer is found, about one in three of us will probably have to undergo surgery, chemotherapy or radiotherapy at some point in our lives. Traditional radiotherapy uses X-rays to target cancerous tissue, but there is growing interest in using particles instead. Beams of hadrons, such as protons, neutrons and ions, offer important advantages over X-ray radiotherapy. Their clinical applications, however, are much less widespread. PHYSICS Antiprotons excel at cancer treatment A beam of antiprotons should be four times better at destroying tumours than current proton-beam therapies, claim physicists at CERN. The discovery could lead to new cancer-treatment techniques that minimize the damage done to healthy tissue surrounding tumours (Radiother. Oncol. 2006 doi:10.1016/j.radonc.2006.09.012). PHYSICS Neutrino Nobel laureate dies 30 August 2006 Melvyn Schwartz, who shared the 1988 Nobel Prize for Physics, died on Monday at the age of 73. He shared the prize with Leon Lederman and Jack Steinberger for developing a way to generate beams of neutrinos. Their work, which took place at the Brookhaven National Laboratory in the US in the early 1960s, also showed that neutrinos can exist in more than one type or "flavour". PHYSICS From the present to the past Cambridge physicist Stephen Hawking and his CERN colleague Thomas Hertog have proposed a radical new approach to understanding the universe that studies it from the "top down" rather than the "bottom up" as in traditional models. The approach acknowledges that the universe did not have just one unique beginning and history but a multitude of different beginnings and histories, and that it has experienced them all. But because most of these other alternative histories disappeared very early after the Big Bang to leave behind the universe we observe today, the best way to understand the past, they say, is to trace our knowledge back from the present (Phys. Rev. D 73 123527). PHYSICS Physics goes to the movies The popularity of a particular film largely depends on word-of-mouth recommendations according to a new study by statistical physicists in the US and Chile. César Hidalgo of the University of Notre Dame and colleagues have also developed a quantitative indicator of a film's quality, which they say could be used by film producers and studios to estimate the commercial value of a movie (New J. Phys. 8 52). PHYSICS Hottest topic in physics revealed Carbon nanotubes are the hottest topic in physics, according to a new way of ranking the popularity of different scientific fields. Nanowires are second, followed by quantum dots, fullerenes, giant magnetoresistance, M-theory and quantum computation. The new ranking has been developed by Michael Banks, a PhD student at the Max Planck Institute for Solid-State Physics in Stuttgart, Germany. He thinks the new index could be a quick and simple way of determining the most important subject areas in physics and could even help graduate students choose which field to do their PhD in (physics/0604216). PHYSICS World's most creative physicist revealed The Nobel prize-winner Philip Anderson is the most creative physicist in the world, according to a new analysis of scientific research papers. Steven Weinberg -- another Nobel laureate -- is the second most creative physicist, followed by Ed Witten in third. The study has been carried out by José Soler, a statistical physicist at the University of Madrid, who says that his "creativity index" could help universities to recruit and promote the best staff (physics/0608006). PHYSICS Instituto de Física da UFRGS receberá R$ 3. 240. 865,00 para pesquisas em Nanotecnologia O Ministério da Ciência e tecnologia, por meio da FINEP (Financiadora de Estudos e Projetos) irá liberar verba para a implantação no Instituto de Física da UFRGS dos núcleos de produção, processamento e caracterização de materiais nanoscópicos e de simulação e tratamento de imagem. PHYSICS Tehran to Talk With EU Before IAEA Meeting Iran Negotiator Says Tehran Will Hold Talks With EU Before U.N. Nuclear Watchdog Meeting PHYSICS US seals nuclear cooperation pact with India President George W. Bush on Thursday pledged to end India's pariah status in the global nuclear order after more than three decades of isolation by offering it access to the international market for nuclear fuel and technology. PHYSICS Quantum computer solves problem, without running Paul Kwiat, right, a John Bardeen Professor of Electrical and Computer Enginering and Physics, and graduate student Onur Hosten have found an exotic way of determining an answer to an algorithm – without ever running the algorithm. PHYSICS 'Physics for poets' takes CMC stage Judging from her short history as a playwright, it's hard to tell if Kristin Carlson is obsessed with William Blake, the 18th-century English poet and artist, or Catherine Blake, his wife of 40 years. Or neither of the two. PHYSICS Photon physics used to foil hackers A University of Toronto scientist says he is using photon physics to prevent hackers from obtaining sensitive government and business data. PHYSICS Seventh annual Physics Circus Thousand of students, parents and teachers are heading to Baylor University this week for the seventh annual Physics Circus. PHYSICS Iran nuclear talks 'not going easily': Putin LONDON, February 22 (IranMania) - Talks with Iran on a Russian plan to resolve international tensions over Tehran's nuclear programme are making little progress, Russian President Vladimir Putin said Wednesday, AFP reported. PHYSICS Iran's N-Physics Conference opens in Mashhad LONDON, February 23 (IranMania) -The inaugural ceremony of Iran's Nuclear Physics Conference, which opened in the provincial capital of Mashhad on Wednesday, was attended by more than 400 university instructors and students from across the country, IRNA reported. PHYSICS Lab boss makes surprise exit Praveen Chaudhari is to step down as director of the Brookhaven National Laboratory near New York at the end of April, a post he has held for three years. Chaudhari cited personal reasons for his unexpected decision, which was announced less than two weeks after US President George Bush put forward significant new funding for Brookhaven and other nuclear physics laboratories next year. |
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”...O que tenho para dizer à Universidade [..] ? Tenho que dizer que se pinte de negro,
que se pinte de mulato, não só entre os alunos, mas também entre os professores, que se
pinte de operários e de camponeses, que se pinte de povo, porque a Universidade não é
patrimônio de ninguém e pertence ao povo...”
Dr. Ernesto Che Guevara
Les vraies conquêtes, les seules qui ne donnent aucun regret, sont celles que l'on fait sur l'ignorance.
Napoléon Bonaparte (1769 - 1821)
Conta-se que Napoleão, após haver folheado a obra Mecânica Celestial, teria observado não haver menção de Deus. Laplace teria respondido:
“Não necessito dessa hipótese.”
Quando ouviu a história, Lagrange afirmou:
“Mas é uma hipótese maravilhosa. Ela explica tantas coisas."
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