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Culture · Geography · Health · History · Mathematics · Natural sciences · Philosophy · Religion · Society · Technology
Scientists maintain that scientific investigation must adhere to the scientific method, a process for properly developing and evaluating natural explanations for observable phenomena based on empirical study and independent verification. Science, therefore, avoids supernatural explanations until all other natural possibilities have been considered, and rejects arguments from authority. Fields of science are commonly classified along two major lines: Natural sciences, which study natural phenomena; and Social sciences, which study human behavior and societies. Whether mathematics is a science is a matter of perspective. Fields of science can be further distinguished as pure science or applied science. Pure science is principally involved with the discovery of new truths with less (or no) regard to their applications. Applied science is principally involved with the application of existing knowledge in new ways.
Teflon is the brand name of the polymer polytetrafluoroethylene (PTFE) discovered by Roy J. Plunkett (1910–1994) of DuPont in 1938 and introduced as a commercial product in 1946. It is a fluoropolymer but not a thermoplastic in the true sense.
PTFE has the lowest coefficient of friction of any known solid material. It is used as a non-stick coating for pans and other cookware. PTFE is very non-reactive and is often used in containers and pipework for reactive chemicals. Its melting point is 327 °C, but its properties degrade above 260 °C. At this point gaseous fluorine compounds are released that are dangerous to humans. Other polymers with similar composition are known by the Teflon name: fluorinated ethylene-propylene (FEP) and perfluoroalkoxy polymer resin (PFA). They retain the useful properties of PTFE of low friction and non-reactivity, but are more easily formable. FEP is softer than PTFE and melts at 260 °C; it is highly transparent and resistant to sunlight. Craniometry is the technique of measuring the bones of the skull. Craniometry was once intensively practiced in anthropology and ethnology. Human skulls can be classified into three main categories based on cephalic index: dolichocephalic: long and thin; brachycephalic: short and broad; mesocephalic: intermediate length and breadth. Ayurveda the traditional medicinal science of India,had already mentioned about the different measurements of the bones and joints.This science is almost 4000 years old.This science is called as PRAMANA SHARIR i.e. science of measurements.Loads of references can be found in classical texts of Ayurveda i.e. Charak Samhita, Sushrut samhita and Ashtang hridaya.
Brian Greene (born February 9, 1963, New-York), is a physicist at Columbia University. His book The Elegant Universe: Superstrings, Dimensions, and the Quest for the Ultimate Theory was a finalist for the Pulitzer Prize in nonfiction, and winner of The Aventis Prizes for Science Books in 2000. The Elegant Universe was later made into a PBS television special with Dr. Greene as the narrator. His second book, The Fabric of the Cosmos (2004), is about space, time, and the nature of the universe. Aspects covered in this book include non-local particle entanglement as he relates to special relativity and basic explanations of string theory. It is an examination of the very nature of matter and reality, covering such topics as spacetime and cosmology, origins and unification, and including an exploration into reality and the imagination.
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