Notes to Book: Curt Suplee: Physics in the 20th Century (1999)

Laser = light amplification by stimulated emission of radiation
Precursor: Maser = microwave amplication by stimulated emission of radiation

Microwaves have longer wavelengths and therfore less energy than visible light

Einstein: Atoms can emit photons in two different ways: spontaneous (e.g., sun, light bulbs) and stimulated (maser, laser).

When an atom is excited by a quantum energy that exactly corresponds to one of its specific allowed energy states (postulated by Niels Bohr), it absorbs the energy, but then almost immediately sheds it by emitting a photon. Variation of effect: If an electron is already in an excited state and then struck be a photon of excactly the right energy, it emits two photons. The new photon is identical to the first; each quantum of radiation is perfectly matched, meaning the new photon is exacty in phase with the one that stimulated its emission: 'coherent'.

Snippets:
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Video: "Cassatt" (Portrait of an Artist Volume 2: May Cassatt. Impressionist from Philadelphia. Produced by WNET/Thirteen for 'Women in Art' (1977), 30 min. Cassatt was, after Whistler, the most important American Impressionist Painter; she spent much time painting in Paris; she was a close friend of Degas; they thoroughly critiqued each others work; especially known for her mother-child portraits.
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Video: Big. w/ Tom Hanks. A 13-year old boy makes a wish at a fair and slips into the body of a grown-up. Funny; childish at times; Hanks plays the role real well.
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Brain-Teaser: The Flash Mind Reader. Can you find out how it works?
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Design: Ritzenhoff (in German). Lots of pictures.
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Designer: Michal Shalev, b. 1958 in Tel-Aviv, Israel; carpet and textile designs, also curtains, paper products, porcelain and shower curtains; has been working closely with such German firms as Ritzenhoff, Karstadt, Rosenthal, Design House since 1994.
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Metric System Prefixes: Exta = 10^18, Peta = 10^15, Tera = 10^12, Giga = 10^9, Mega = 10^6, Kilo = 10^3
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