In physical cosmology, the Big Bang is the scientific theory that the universe emerged from a tremendously dense and hot state about 13.7 billion years ago. The theory is based on the observations indicating the expansion of space (in accord with the Robertson-Walker model of general relativity) as indicated by the Hubble redshift of distant galaxies taken together with the cosmological principle.
Extrapolated into the past, these observations show that the universe has expanded from a state in which all the matter and energy in the universe was at an immense temperature and density. Physicists do not widely agree on what happened before this, although general relativity predicts a gravitational singularity (for reporting on some of the more notable speculation on this issue, see cosmogony).
The term Big Bang is used both in a narrow sense to refer to a point in time when the observed expansion of the universe (Hubble's law) began — calculated to be 13.7 billion (1.37 × 1010) years ago (±2%) — and in a more general sense to refer to the prevailing cosmological paradigm explaining the origin and expansion of the universe, as well as the composition of primordial matter through nucleosynthesis as predicted by the Alpher-Bethe-Gamow theory.
Creative Students of Govt. High School, Avanavanchery, bonded with lifelong friendship decided to blog together. They gave me the opportunity to co-operate with them. I really enjoy their company. May GOD bless the fellowship.
Sunday, June 21, 2009
What Is A Fairy Tale
A fairy tale is a fictional story that may feature folkloric characters such as fairies, goblins, elves, trolls, giants, and talking animals, and usually enchantments, often involving a far-fetched sequence of events. In modern-day parlance, the term is also used to describe something blessed with princesses, as in "fairy tale ending" (a happy ending) or "fairy tale romance", though not all fairy tales end happily. Colloquially, a "fairy tale" or "fairy story" can also mean any far-fetched story. Fairy tales commonly attract young children since they easily understand the archetypal characters in the story.
In cultures where demons and witches are perceived as real, fairy tales may merge into legendary narratives, where the context is perceived by teller and hearers as having historical actuality. However, unlike legends and epics they usually do not contain more than superficial references to religion and actual places, persons, and events; they take place once upon a time rather than in actual times.
Fairy tales are found in oral folktales and in literary form. The history of the fairy tale is particularly difficult to trace, because only the literary forms can survive. Still, the evidence of literary works at least indicates that fairy tales have existed for thousands of years, although not perhaps recognized as a genre; the name "fairy tale" was first ascribed to them by Madame d'Aulnoy. Literary fairy tales are found over the centuries all over the world, and when they collected them, folklorists found fairy tales in every culture. Fairy tales, and works derived from fairy tales, are still written today
In cultures where demons and witches are perceived as real, fairy tales may merge into legendary narratives, where the context is perceived by teller and hearers as having historical actuality. However, unlike legends and epics they usually do not contain more than superficial references to religion and actual places, persons, and events; they take place once upon a time rather than in actual times.
Fairy tales are found in oral folktales and in literary form. The history of the fairy tale is particularly difficult to trace, because only the literary forms can survive. Still, the evidence of literary works at least indicates that fairy tales have existed for thousands of years, although not perhaps recognized as a genre; the name "fairy tale" was first ascribed to them by Madame d'Aulnoy. Literary fairy tales are found over the centuries all over the world, and when they collected them, folklorists found fairy tales in every culture. Fairy tales, and works derived from fairy tales, are still written today
Transhumanism
Transhumanism is an international intellectual and cultural movement supporting the use of science and technology to improve human mental and physical characteristics and capacities. The movement regards aspects of the human condition, such as disability, suffering, disease, aging, and involuntary death as unnecessary and undesirable. Transhumanists look to biotechnologies and other emerging technologies for these purposes. Dangers, as well as benefits, are also of concern to the transhumanist movement. It is often symbolized by H+ or h+.
Although the first known use of the term "transhumanism" dates from 1957, the contemporary meaning is a product of the 1980s when futurists in the United States began to organize what has since grown into the transhumanist movement. Transhumanist thinkers predict that human beings may eventually be able to transform themselves into beings with such greatly expanded abilities as to merit the label "posthuman". Transhumanism is therefore sometimes referred to as "posthumanism" or a form of transformational activism influenced by posthumanist ideals.
Transhumanist foresight of a transformed future humanity has attracted many supporters and detractors from a wide range of perspectives. Transhumanism has been described by one critic, Francis Fukuyama, as the world's most dangerous idea, while one proponent, Ronald Bailey, counters that it is the "movement that epitomizes the most daring, courageous, imaginative, and idealistic aspirations of humanity".
Although the first known use of the term "transhumanism" dates from 1957, the contemporary meaning is a product of the 1980s when futurists in the United States began to organize what has since grown into the transhumanist movement. Transhumanist thinkers predict that human beings may eventually be able to transform themselves into beings with such greatly expanded abilities as to merit the label "posthuman". Transhumanism is therefore sometimes referred to as "posthumanism" or a form of transformational activism influenced by posthumanist ideals.
Transhumanist foresight of a transformed future humanity has attracted many supporters and detractors from a wide range of perspectives. Transhumanism has been described by one critic, Francis Fukuyama, as the world's most dangerous idea, while one proponent, Ronald Bailey, counters that it is the "movement that epitomizes the most daring, courageous, imaginative, and idealistic aspirations of humanity".
Iridium
Iridium is the chemical element with atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum family, iridium is the second densest element and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can even be flammable. Iridium was discovered in 1803 by Smithson Tennant among insoluble impurities in natural platinum from South America. It is one of the rarest elements in the Earth's crust, with annual production and consumption of only three tonnes. However, iridium does find a number of specialized industrial and scientific applications. Iridium is employed when high corrosion resistance and high temperatures are needed, as in spark plugs, crucibles for recrystallization of semiconductors at high temperatures, electrodes for the production of chlorine in the chloralkali process, and radioisotope thermoelectric generators used in unmanned spacecraft. Iridium is found in meteorites with an abundance much higher than its average abundance in the Earth's crust. It is thought that due to the high density and siderophilic ("iron-loving") character of iridium, most of the iridium on Earth is found in the inner core of the planet.
Iridium
Iridium is the chemical element with atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum family, iridium is the second densest element and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can even be flammable. Iridium was discovered in 1803 by Smithson Tennant among insoluble impurities in natural platinum from South America. It is one of the rarest elements in the Earth's crust, with annual production and consumption of only three tonnes. However, iridium does find a number of specialized industrial and scientific applications. Iridium is employed when high corrosion resistance and high temperatures are needed, as in spark plugs, crucibles for recrystallization of semiconductors at high temperatures, electrodes for the production of chlorine in the chloralkali process, and radioisotope thermoelectric generators used in unmanned spacecraft. Iridium is found in meteorites with an abundance much higher than its average abundance in the Earth's crust. It is thought that due to the high density and siderophilic ("iron-loving") character of iridium, most of the iridium on Earth is found in the inner core of the planet.
Tuesday, April 21, 2009
Did You Know.........??????
* ...that in the Large Hadron Collider (LHC) (pictured) protons, accelerated to the energy of 7 TeV, move at 99.999999% of light speed and become 7,500 times heavier than at rest?
* ...that, at a speed of 299,792,458 m/s, light can travel to the Moon in 1.2 seconds?
* ...that the submarine telescope ANTARES, intended to detect neutrinos, may also be used to observe bioluminescent plankton and fish?
* ...that lasers can be used to separate two isotopes very efficiently?
* ...that neutron stars are so dense that a teaspoonful (5 mL) would have ten times the mass of all human world population?
* ...that every year, the Moon moves 3.82 cm away from Earth?
* ...that gold leaf is about 500 atoms thick?
* ...that in the Large Hadron Collider (LHC) (pictured) protons, accelerated to the energy of 7 TeV, move at 99.999999% of light speed and become 7,500 times heavier than at rest?
* ...that, at a speed of 299,792,458 m/s, light can travel to the Moon in 1.2 seconds?
* ...that the submarine telescope ANTARES, intended to detect neutrinos, may also be used to observe bioluminescent plankton and fish?
* ...that lasers can be used to separate two isotopes very efficiently?
* ...that neutron stars are so dense that a teaspoonful (5 mL) would have ten times the mass of all human world population?
* ...that every year, the Moon moves 3.82 cm away from Earth?
* ...that gold leaf is about 500 atoms thick?
Quantum Computing
Alanine, as used in NMR implementation of error correction. Qubits are dictated by spin states of carbon atoms.
A quantum computer is any device for computation that makes direct use of distinctively quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data. In a classical (or conventional) computer, the amount of data is measured by bits; in a quantum computer, it is measured by qubits. The basic principle of quantum computation is that the quantum properties of particles can be used to represent and structure data, and that devised quantum mechanisms can be used to perform operations with this data. For a generally accessible overview of quantum computing, see Quantum Computing with Molecules, an article in Scientific American by Neil Gershenfeld and Isaac L. Chuang.
Experiments have already been carried out in which quantum computational operations were executed on a very small number of qubits. Research in practical areas continues at a frantic pace; see Quantum Information Science and Technology Roadmapfor a sense of where the research is heading. Many national government and military funding agencies support quantum computing research, to develop quantum computers for both civilian and national security purposes, such as cryptanalysis.
A quantum computer is any device for computation that makes direct use of distinctively quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data. In a classical (or conventional) computer, the amount of data is measured by bits; in a quantum computer, it is measured by qubits. The basic principle of quantum computation is that the quantum properties of particles can be used to represent and structure data, and that devised quantum mechanisms can be used to perform operations with this data. For a generally accessible overview of quantum computing, see Quantum Computing with Molecules, an article in Scientific American by Neil Gershenfeld and Isaac L. Chuang.
Experiments have already been carried out in which quantum computational operations were executed on a very small number of qubits. Research in practical areas continues at a frantic pace; see Quantum Information Science and Technology Roadmapfor a sense of where the research is heading. Many national government and military funding agencies support quantum computing research, to develop quantum computers for both civilian and national security purposes, such as cryptanalysis.
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