Showing posts with label History. Show all posts
Showing posts with label History. Show all posts
Primordial gravitational waves, The Inflation and The Big Bang
The detection of gravitational waves by a team of scientists involved in the BICEP 2 collaboration is a prodigious discovery similar in importance and scale
to the discovery of Higgs field and it has consequences for cosmology and our perception of the
universe. The discovery has confirmed the last untested prediction of
Einstein's Relativity.
The BICEP 2 collaboration, the theoretical physicist Alan Guth, who proposed the Inflationary cosmology in 1980, the Russian American physicist Andrei Linde, who is the father of the Theory of Inflation and Eternal Inflation, may be crowned with Nobel Prize.
The Inflation offers an explanation for some very important problems in cosmology. Inflation makes one prediction, the existence of a primordial gravitational wave background with particular properties. Such gravitational waves would leave a characteristic signature in the CMB maps, namely a slight circular polarization waves.
For detecting the circular polarization wave or the called the B mode signal, BICEP 2 was able to measure features that are 1/100000000 of the CMB signal, which is itself 1/100000000 of the ambient thermal radiation. The BICEP 2 has got to be one of the most precise measurements in the history of science.
The existence of the CMB was a prediction of the Big Bang Theory and its detection provided the best evidence for the Big Bang, the BICEP 2 is the evidence that convinces us that Inflation really happened.
The BICEP 2 collaboration, the theoretical physicist Alan Guth, who proposed the Inflationary cosmology in 1980, the Russian American physicist Andrei Linde, who is the father of the Theory of Inflation and Eternal Inflation, may be crowned with Nobel Prize.
The Inflation offers an explanation for some very important problems in cosmology. Inflation makes one prediction, the existence of a primordial gravitational wave background with particular properties. Such gravitational waves would leave a characteristic signature in the CMB maps, namely a slight circular polarization waves.
For detecting the circular polarization wave or the called the B mode signal, BICEP 2 was able to measure features that are 1/100000000 of the CMB signal, which is itself 1/100000000 of the ambient thermal radiation. The BICEP 2 has got to be one of the most precise measurements in the history of science.
The existence of the CMB was a prediction of the Big Bang Theory and its detection provided the best evidence for the Big Bang, the BICEP 2 is the evidence that convinces us that Inflation really happened.
Ancient Scientific Instruments
David Flores is an amateur scientist from Spain and he like building ancient scientific instruments. He has been building more than 100 instruments and all are working models.
Chinese Astronomy
Despite China’s enormous extent and local diversity, its literate elite, because of their classical educations, shared not only a language but values and patterns of thought. Among these values was overwhelming prestige for the civil service. One generation of talented astronomers after another sought the only employer ready to provide large, long-term investment in scientific research and development. The government supported large-scale astronomical projects, from the 2nd century BC on, because of the ideology that justified its power. It claimed that the imperial house was chosen by Heaven to shape society in its image. The monarch’s personal virtue and charisma, not his managerial skills, kept him in touch with the cosmic order and enabled him to keep the state in harmony with it. This doctrine included the notion of the Mandate of Heaven. Heaven chose an exceptionally virtuous family to rule. When eventually its descendants no longer maintained that virtue, Heaven transferred the mandate to a worthier family. The conquest that ended a dynasty and began a new one was thus not a crime—if it succeeded.
As a result, the imperial court included an amply staffed Bureau of Astronomy. Its responsibilities for ASTROLOGY and mathematical astronomy were intimately related. Its officials scrutinized the sky for omens, recorded them, determined their meaning from the Bureau’s archives and reported them so that the emperor and his officials could determine how to respond.
The emperor symbolically expressed his control over time as well as space by issuing the annual CALENDAR (actually an ephemeris or almanac that included eclipses and planetary phenomena). He expected the Bureau to incorporate in it the most accurate predictions possible, particularly those of eclipses. As a result of this ongoing state sponsorship, the published historical record offers unbroken, dated records of most important celestial phenomena, and detailed accounts of the evolving methods used to make EPHEMERIDES, for more than two millennia.
Chinese degree measurement was not derived from the Babylonian sexagesimal system. It was based on the du, originally a measure of time intervals between meridian transits, but after about AD 180 redefined as the distance of one day’s mean solar travel.
The time of observations was generally measured by water clocks, of which several examples survive from the last two centuries BC.
Since China was the predominant culture in East Asia, the institutions and methods of its official astronomy provided a foundation for counterparts (always with local character)in Korea, Japan and Vietnam. The desire for accurate prediction of solar eclipses motivated Chinese to hire experts in the geometric methods of the Greek tradition. They employed Indians from 665 on, Muslims during the Mongol occupation (1279–1367) and Jesuit missionaries in the 17th and 18th centuries. The latter, in fact, by offering the Manchu invaders their skills at casting cannon and computing the mandatory imperial ephemerides, took control of the Astronomical Bureau.
All of the great historical civilizations have exchanged ideas and artifacts since the New Stone Age. China was so isolated from Europe, the Middle East and India that
outside scientific influence remained controllable until the mid-19th century. It remained a centrally ruled empire larger than all of Europe for more than 2000 yr. Even in brief periods of division, the continuity of its high culture, unlike that of Europe for much of the Middle Ages, was never interrupted.
As a result, the imperial court included an amply staffed Bureau of Astronomy. Its responsibilities for ASTROLOGY and mathematical astronomy were intimately related. Its officials scrutinized the sky for omens, recorded them, determined their meaning from the Bureau’s archives and reported them so that the emperor and his officials could determine how to respond.
The emperor symbolically expressed his control over time as well as space by issuing the annual CALENDAR (actually an ephemeris or almanac that included eclipses and planetary phenomena). He expected the Bureau to incorporate in it the most accurate predictions possible, particularly those of eclipses. As a result of this ongoing state sponsorship, the published historical record offers unbroken, dated records of most important celestial phenomena, and detailed accounts of the evolving methods used to make EPHEMERIDES, for more than two millennia.
Chinese degree measurement was not derived from the Babylonian sexagesimal system. It was based on the du, originally a measure of time intervals between meridian transits, but after about AD 180 redefined as the distance of one day’s mean solar travel.
The time of observations was generally measured by water clocks, of which several examples survive from the last two centuries BC.
Since China was the predominant culture in East Asia, the institutions and methods of its official astronomy provided a foundation for counterparts (always with local character)in Korea, Japan and Vietnam. The desire for accurate prediction of solar eclipses motivated Chinese to hire experts in the geometric methods of the Greek tradition. They employed Indians from 665 on, Muslims during the Mongol occupation (1279–1367) and Jesuit missionaries in the 17th and 18th centuries. The latter, in fact, by offering the Manchu invaders their skills at casting cannon and computing the mandatory imperial ephemerides, took control of the Astronomical Bureau.
All of the great historical civilizations have exchanged ideas and artifacts since the New Stone Age. China was so isolated from Europe, the Middle East and India that
outside scientific influence remained controllable until the mid-19th century. It remained a centrally ruled empire larger than all of Europe for more than 2000 yr. Even in brief periods of division, the continuity of its high culture, unlike that of Europe for much of the Middle Ages, was never interrupted.
Mass and energy are both but different manifestations of the same thing
It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing -- a somewhat unfamiliar conception for the average mind. Furthermore, the equation E is equal to m c-squared, in which energy is put equal to mass, multiplied by the square of the velocity of light, showed that very small amounts of mass may be converted into a very large amount of energy and vice versa. The mass and energy were in fact equivalent, according to the formula mentioned before. This was demonstrated by Cockcroft and Walton in 1932, experimentally.
Galileo: 400 years
When Galileo heard about a spyglass invented in Holland that made distant objects seem near, he immediately grasped its potentialities for the furtherance of his own career. How much about its mode of construction he learnt from others and how much he worked out for himself is not quite clear. What is clear, however, is that his tested skill in instrument-making gave him an advantage over his competitors and a lead in telescope-making that he maintained over the crucial two-year period (1609–11) within which all the major astronomical discoveries within the reach of a telescope of this type were made by him. By August 1609 he could present the Doge of Venice with a roughly 9x telescope. Impressed by the military and commercial potential of the ‘perspicillum’, a grateful Venetian Senate promised to double his salary.
However, Galileo saw even greater potential for himself elsewhere. By January 1610 he had constructed a 20x instrument and had discovered Earth-like irregularities on the Moon, four satellites orbiting Jupiter, and stars beyond numbering that were invisible to the naked eye. Later in 1610 came moving sunspots, the phases of Venus and the oddly changing shape of Saturn. Galileo rushed his first discoveries into print, dedicating the Sidereal Messenger to his former pupil, now Cosimo II, Grand Duke of Tuscany, and dubbing Jupiter’s moons the ‘Medicean’ planets. These shrewd gestures gained him the position he had long coveted as Mathematician and Philosopher to the Grand Duke. His little book caused an instant sensation and made him Europe’s most famous astronomer.
His lunar observations, vividly chronicled in the Sidereus Nuncius, made the greatest impact, perhaps, on the general public. Patches of light and shadow could now be plausibly identified as Earth-like features. Prominent among them were what seemed to be lunar mountains, whose peaks could be seen as spots of light at lunar dawn while the lowlands below them remained in shadow. And the mountains’ own shadows shortened as the lunar noon approached, just as one would expect.
The discovery that four satellites circled Jupiter showed that, contrary to Aristotle’s doctrine of natural motion, there is more than one center of rotation in the planetary system. It also eliminated an objection to the Copernican claim that the Earth carried its Moon along as it circled the Sun.
The phases of Venus from crescent to full and back again became Galileo’s most potent argument against the older cosmology. If Venus and the Sun both orbit the
Earth, with Venus below the Sun, Venus should always show a crescent shape to Earth, if illuminated by the Sun. If, however, Venus and Earth both orbit the Sun, Venus
should run through the same sequence of phases as does our own moon.
Galileo’s contributions to astronomy were of two very different kinds. First were the stunning observational discoveries of 1609–11. These did not involve the calculational feats of his great predecessors, Ptolemy, Copernicus and Kepler. Galileo was fortunate to be the first to be enabled to see in the heavens what no one before him had seen; what made him a great astronomer was his ability to grasp the significance for cosmology of what he saw. Second was his furtherance of the case for the Copernican system. He did more than any other single person to bring about the displacement of the Earth from its privileged place at the cosmic center with the vast shift in world view that followed.
However, Galileo saw even greater potential for himself elsewhere. By January 1610 he had constructed a 20x instrument and had discovered Earth-like irregularities on the Moon, four satellites orbiting Jupiter, and stars beyond numbering that were invisible to the naked eye. Later in 1610 came moving sunspots, the phases of Venus and the oddly changing shape of Saturn. Galileo rushed his first discoveries into print, dedicating the Sidereal Messenger to his former pupil, now Cosimo II, Grand Duke of Tuscany, and dubbing Jupiter’s moons the ‘Medicean’ planets. These shrewd gestures gained him the position he had long coveted as Mathematician and Philosopher to the Grand Duke. His little book caused an instant sensation and made him Europe’s most famous astronomer.
His lunar observations, vividly chronicled in the Sidereus Nuncius, made the greatest impact, perhaps, on the general public. Patches of light and shadow could now be plausibly identified as Earth-like features. Prominent among them were what seemed to be lunar mountains, whose peaks could be seen as spots of light at lunar dawn while the lowlands below them remained in shadow. And the mountains’ own shadows shortened as the lunar noon approached, just as one would expect.
The discovery that four satellites circled Jupiter showed that, contrary to Aristotle’s doctrine of natural motion, there is more than one center of rotation in the planetary system. It also eliminated an objection to the Copernican claim that the Earth carried its Moon along as it circled the Sun.
The phases of Venus from crescent to full and back again became Galileo’s most potent argument against the older cosmology. If Venus and the Sun both orbit the
Earth, with Venus below the Sun, Venus should always show a crescent shape to Earth, if illuminated by the Sun. If, however, Venus and Earth both orbit the Sun, Venus
should run through the same sequence of phases as does our own moon.
Galileo’s contributions to astronomy were of two very different kinds. First were the stunning observational discoveries of 1609–11. These did not involve the calculational feats of his great predecessors, Ptolemy, Copernicus and Kepler. Galileo was fortunate to be the first to be enabled to see in the heavens what no one before him had seen; what made him a great astronomer was his ability to grasp the significance for cosmology of what he saw. Second was his furtherance of the case for the Copernican system. He did more than any other single person to bring about the displacement of the Earth from its privileged place at the cosmic center with the vast shift in world view that followed.
Bill Gates and Richard Feynman
Bill Gates has a dream of taking some classic physics lectures and making them available free over the Web. The lectures, done in 1964 by Richard Feynman, take notions such as gravity and explains how it work. Gates is making the collection available free from the Microsoft Research Web site.
History of Physicists in Industry
This is the first systematic study of the organizational structure, communications patterns, and archival records of industrial physicists in the U.S., and it provides general guidelines for understanding and documenting their work. The study confirms that the organization and management of industrial research and development is volatile, changing in response to economic cycles, new managers and management philosophies, and a variety of other factors. It also confirms that historically valuable records that document R&D are at risk and, in fact, are often scattered and lost.
The final report is online at http://www.aip.org/history/pubs/HOPI_Final_report.pdf.
The final report is online at http://www.aip.org/history/pubs/HOPI_Final_report.pdf.
OPEN MILTON LAUNCHED FOR MILTON'S 400TH BIRTHDAY
The 9th of December 2008 was John Milton's 400th birthday. To celebrate this 'Open Milton' – an open set of Milton's works, together with ancillary information and tools, in a form designed for reuse. In addition to the works themselves there is a chronology, statistics, a concordance and search facilities.
Open Milton
http://www.openmilton.org/
Open Milton
http://www.openmilton.org/
Development of Inventions and Creative Ideas
OCW: Development of Inventions and Creative Ideas
Spring 2008
Spring 2008
This course examines the role of the engineer as patent expert and as technical witness in court and patent interference and related proceedings. It discusses the rights and obligations of engineers in connection with educational institutions, government, and large and small businesses.
The Technological Revolution
The Technological Revolution
by Maury Klein
The Newsletter of FPRI’s Wachman Center for International Education
Vol. 13, No 18
July 2008
by Maury Klein
The Newsletter of FPRI’s Wachman Center for International Education
Vol. 13, No 18
July 2008
Most high schools and even colleges and universities do not offer courses on technology in America, which is extraordinary because technology plays such a dominant role in our life.
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