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Matter

Matter
Before the 20th century, the term matter included ordinary matter composed of atoms and excluded other energy phenomena such as light or sound. This concept of matter may be generalized from atoms to include any objects having mass even when at rest, but this is ill-defined because an object's mass can arise from its (possibly massless) constituents' motion and interaction energies. Thus, matter does not have a universal definition, nor is it a fundamental concept in physics today. Matter is also used loosely as a general term for the substance that makes up all observable physical objects.[1][2] All the objects from everyday life that we can bump into, touch or squeeze are composed of atoms. This atomic matter is in turn made up of interacting subatomic particles—usually a nucleus of protons and neutrons, and a cloud of orbiting electrons.[3][4] Typically, science considers these composite particles matter because they have both rest mass and volume. Definition Common definition Quarks

http://en.wikipedia.org/wiki/Matter

Related:  stoicismNew Earth SpaceMatter

Cosmopolitanism Cosmopolitanism is the ideology that all human beings belong to a single community, based on a shared morality. A person who adheres to the idea of cosmopolitanism in any of its forms is called a cosmopolitan or cosmopolite. A cosmopolitan community might be based on an inclusive morality, a shared economic relationship, or a political structure that encompasses different nations. In a cosmopolitan community individuals from different places (e.g. nation-states) form relationships of mutual respect. As an example, Kwame Anthony Appiah suggests the possibility of a cosmopolitan community in which individuals from varying locations (physical, economic, etc.) enter relationships of mutual respect despite their differing beliefs (religious, political, etc.).[1]

Here's How You Can Help Scientists Study Sex, Whales, and Distant Galaxies "There is so much we don't know!" said Dick Vane-Wright, the Keeper of Entomology at the London Museum of Natural History when author Sharman Apt Russell was asking about butterflies. "You could spend a week studying some obscure insect and you would then know more than anyone else on the planet. Wave–particle duality Origin of theory[edit] The idea of duality originated in a debate over the nature of light and matter that dates back to the 17th century, when Christiaan Huygens and Isaac Newton proposed competing theories of light: light was thought either to consist of waves (Huygens) or of particles (Newton). Through the work of Max Planck, Albert Einstein, Louis de Broglie, Arthur Compton, Niels Bohr, and many others, current scientific theory holds that all particles also have a wave nature (and vice versa).[2] This phenomenon has been verified not only for elementary particles, but also for compound particles like atoms and even molecules. For macroscopic particles, because of their extremely short wavelengths, wave properties usually cannot be detected.[3] Brief history of wave and particle viewpoints[edit] Thomas Young's sketch of two-slit diffraction of waves, 1803

Energy All of the many forms of energy are convertible to other kinds of energy, and obey the conservation of energy. Common energy forms include the kinetic energy of a moving object, the radiant energy carried by light, the potential energy stored by an object's position in a force field,(gravitational, electric or magnetic) elastic energy stored by stretching solid objects, chemical energy released when a fuel burns, and the thermal energy due to an object's temperature. According to mass–energy equivalence, any object that has mass when stationary,(called rest mass) also has an equivalent amount of energy whose form is called rest energy. Conversely, any additional energy above the rest energy will increase an object's mass. Isotope The three naturally-occurring isotopes of hydrogen. The fact that each isotope has one proton makes them all variants of hydrogen: the identity of the isotope is given by the number of neutrons. From left to right, the isotopes are protium (1H) with zero neutrons, deuterium (2H) with one neutron, and tritium (3H) with two neutrons. Isotopes are variants of a particular chemical element such that, while all isotopes of a given element have the same number of protons in each atom, they differ in neutron number. The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place". Thus, different isotopes of a single element occupy the same position on the periodic table.

Susanne Bobzien Susanne Bobzien, FBA is a German-born philosopher,[1] whose research interests focus on philosophy of logic and language, determinism and freedom, and ancient philosophy.[2] She currently is Senior Research Fellow at All Souls College, Oxford and Professor of Philosophy at the University of Oxford.[3] Education[edit] Bobzien was born in Hamburg, Germany in 1960.[1] She graduated in 1985 with an M.A. Us vs the universe: 8 ways we bend the laws of physics Cookies on the New Scientist website close Our website uses cookies, which are small text files that are widely used in order to make websites work more effectively.

Ionization Ionization (or ionisation, see American and British English spelling differences) is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons. Ionization, often, results from the interaction of an atom or a molecule with an ionizing particle, including charged particles with sufficient energies and energetic photons. A rare case of ionization in the absence of an external particle is the internal conversion process, through which an excited nucleolus transfers its energy to one of the inner-shell electrons and ejects it with high kinetic energy. The ionization process is of particular interest in fundamental science. It is also encountered in many fields of practical interest, ranging from mass spectroscopy to radiotherapy for eliminating cancer cells.

Electric charge Electric charge is a physical property of matter that causes it to experience a force when near other electrically charged matter. There exist two types of electric charges, called positive and negative . Positively charged substances are repelled from other positively charged substances, but attracted to negatively charged substances; negatively charged substances are repelled from negative and attracted to positive. An object will be negatively charged if it has an excess of electrons , and will otherwise be positively charged or uncharged. The SI unit of electric charge is the coulomb (C), although in electrical engineering it is also common to use the ampere-hour (Ah), and in chemistry it is common to use the elementary charge ( e ) as a unit. The symbol Q is often used to denote a charge.

Neutron number This diagram shows the half-life (T½) of various isotopes with Z protons and neutron number N. The neutron number, symbol N, is the number of neutrons in a nuclide. Atomic number (proton number) plus neutron number equals mass number: Z+N=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N - Z = A - 2Z.

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