Physical science

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Physical science describes any of the scientific disciplines which involve the systematic study of the inorganic world, as distinct from the study of the organic world, which is the province of biological science. Physical science is ordinarily thought of as consisting of four broad areas: astronomy, physics, chemistry, and the earth sciences. Each of these is in turn divided into fields and subfields. This article discusses the historical development—with due attention to the scope, principal concerns, and methods—of the first three of these areas. The Earth sciences are discussed in a separate article.

[edit] Basic principles of the physical sciences

The foundations of the physical sciences rests upon key concepts and theories, each of which explains and/or many science is with models a particular aspect of the behavior of nature. As in other sciences, these key concepts and theories came to discovery using the scientific method, which must be found using scientific evidence:

[edit] Basic principles of astronomy

Astronomy is the science of the entire universe beyond the Earth; it includes the Earth's gross physical properties, such as its mass and rotation, insofar as they interact with other bodies in the solar system. Until the 18th century, astronomers were concerned primarily with the Sun, Moon, planets, and comets. During the last two centuries, however, the study of stars, galaxies, nebulas, and the interstellar medium has become increasingly important. Celestial mechanics, the science of the motion of planets and other solid objects within the solar system, was the first testing ground for Newton's laws of motion and thereby helped to establish the fundamental principles of classical (that is, pre-20th-century) physics. Astrophysics, the study of the physical properties of celestial bodies, arose during the 19th century and is closely connected with the determination of the chemical composition of those bodies. In the 20th century physics and astronomy have become more intimately linked through cosmological theories, especially those based on the theory of relativity.

Astronomy includes the following:

• The life and characteristics of stars and galaxies
• Origins of the universe. Physical science uses the Big Bang theory as the commonly accepted scientific theory of the origin of the universe
• A heliocentric solar system. Ancient and primitive cultures saw the earth as the center of the solar system or universe (geocentrism). In the 16th century, Nicolaus Copernicus advanced the ideas of heliocentrism, recognizing the sun as the center of the solar system.
• The structure of the solar system, planets, comets, asteroids, and meteors
• The shape and structure of Earth (roughly spherical, see also Spherical Earth)
• Earth in the Solar System
• Time measurement
• The composition and features of the Moon
• Interactions of the Earth and Moon

(Note: Astronomy should not be confused with astrology, which assumes that people's destiny and human affairs in general are correlated to the apparent positions of astronomical objects in the sky -- although the two fields share a common origin, they are quite different; astronomers embrace the scientific method, while astrologers do not.)

[edit] Basic principles of chemistry

Chemistry is the science of matter mainly at the micro-level. The boundary between physics and chemistry is somewhat arbitrary. As it has developed in the 20th century, physics is concerned with the structure and behaviour of individual atoms and their components, while chemistry deals with the properties and reactions of molecules. These latter depend on energy, especially heat, as well as on atoms; hence, there is a strong link between physics and chemistry. Chemists tend to be more interested in the specific properties of different elements and compounds, whereas physicists are concerned with general properties shared by all matter.

Chemistry includes the following:

• Atomic theory
  • Principles of quantum mechanics
  • The discovery and classification of pure elements
  • Dmitri Mendeleev's creation of The Periodic Table of Chemical Elements showing the relationship of chemical elements
  • Properties of groups, especially metals, and nonmetals
• Water and its properties
  • Structure of the water molecule
  • Properties of water solutions, such as acids, bases, acid-base reaction theories, and salts
• Chemical elements, chemical reactions, and chemical energy
  • Chemical bonds
  • Chemical formula based on chemical notation developed by Jöns Jakob Berzelius's
  • Chemical compounds
  • Chemical equations
• Nuclear chemistry
  • The nature of the atomic nucleus
  • Characterization of radioactive decay, originally discovered by Henri Becquerel
• Organic chemistry, considered to have started in 1828 with the synthesis of urea by Friedrich Woehler
  • Hydrocarbons, (see also Gallery Hydrocarbons)
  • Hydrocarbon derivatives
  • Organic chemistry functional groups

[edit] Basic principles of earth science

Earth science is the science of the planet Earth, the only known life-bearing planet. Its studies include the following:

• Rocks and minerals
• The water cycle and the process of transpiration
• Freshwater, surface water, groundwater
• Oceanography
• Geology
  • Weathering
  • Rocks
• Soil science
• Earth's tectonic structure
• Geomorphology and geophysics
  • Seismology: Stress, strain, and earthquakes
  • Characteristics of mountains and volcanoes
• Characteristics and formation of fossils
• Atmosphere of earth
  • Atmospheric pressure and winds
  • Evaporation, condensation, and humidity
  • Fog and clouds
• Meteorology, weather, climatology, and climate
  • Hydrology, clouds and precipitation
  • Air masses and weather fronts
  • Major storms: thunderstorms, tornadoes, and hurricanes
  • Weather forecasting
  • Major climate groups

[edit] Basic principles of physics

Physics, in its modern sense, was founded in the mid-19th century as a synthesis of several older sciences—namely, those of mechanics, optics, acoustics, electricity, magnetism, heat, and the physical properties of matter. The synthesis was based in large part on the recognition that the different forces of nature are related and are, in fact, interconvertible because they are forms of energy.

[edit] Notable physical scientists

• Aristotle - the last of the three great influential ancient Greek philosophers, although not considered to be a scientist by today's standards, nevertheless, he laid the foundations for today's scientific method by espousing the view that knowledge should be based on empirical observations instead of intuition or faith.
• Archimedes - is considered to be the first mathematical physicist on record, and the best prior to Galileo and Newton. He established the laws of statics, buoyancy, and center of gravity.
• Boyle, Robert - an Irish natural philosopher, is regarded as the "father of modern chemistry" due to his distinction between chemistry and alchemy. His namesake is Boyle's Law of an ideal gas, which he discovered, but his contributions to physical science include the definition of a chemical element, the propagation of sound, among others.
• Copernicus, Nicolaus - a Polish mathematician and economist, is considered by many to be the "father of modern astronomy" due to his detailed explanation of the heliocentric (Sun-centered]] solar system.
• Curie, Marie (maiden name: Sklodowska) - a Polish-born French chemist, was the first female Nobel laureate, the first two-time Nobel laureate, and one of only two individuals to receive the Nobel prize in two different fields. She and her husband, Pierre Curie discovered the two elements Polonium and Radium.
• Einstein, Albert - a theoretical physicist, is widely regarded as the greatest scientist of the 20th century. He proposed the theory of relativity and was awarded the 1921 Nobel Prize for Physics, among other accomplishments.
• Euler, Leonhard - Swiss mathematician and physicist, considered to be one of the greatest mathematicians of all times. His contributions to science includes the Euler-Bournoulli beam equation and Euler equations.
• Galilei, Galileo - an astronomer and physicist, is considered the "father of modern physics," due, in large part, to his conflict with the Roman Catholic Church over the authority of science. However, he has equally impressive scientific contributions to the fields of mechanics, astronomy, and mathematical physics.
• Bacon, Francis - an Elizabethan philosopher, is credited with the philosophical advocation for the Baconian method, the early forerunner of the scientific method.
• Hutton, James - a Scottish geologist, is considered to be the "father of modern geology," for his formulation of uniformitarianism, that the same geological processes operating today operated in the distant past. Based upon that assumption, he maintained that the age of the earth must be much older than a few thousand years.
• Newton, Sir Isaac - a scientist and mathematician, is most renowned for his description of the laws of motion and law of universal gravitation.
• Linus Pauling - an American quantum chemist and biochemist, widely regarded as the premier chemist of the twentieth century. A pioneer in the application of quantum mechanics to chemistry, and one of the founders of molecular biology.
• Thales of Miletus - a pre-Socratic Greek philosopher, is considered to be the father of science becaused he first encouraged naturalistic explanations of the world, without the supernatural.

For a more comprehensive list of scientists, see the list of scientists, especially the following:

• List of astronomers
• List of chemists
• List of geologists
• List of meteorologists
• List of physicists

[edit] See also

• Science
  • Fields of science
    • Behavioral sciences
    • Natural sciences
      • Physical science
    • Social sciences
  • History of science

[edit] External links

• PSI gate - Physical Sciences Information Gateway.
• Physical Sciences Resource Center, for education
• Astronomy: Sky and Telescope magazine
• Chemistry: General Chemistry Online
• Earth science: Earth Science World
• Physics: Physics Centralv

[edit] References

Tillery, B.W. (2005), Physical Science, 6/e, New York: McGraw-Hill. ISBN 0-07-250978-3 (Hardcover) ISBN 0-07-292207-9 (Paperback)