No, but turning a balck body into a white one is no esacpe from a heart attack!
On Jun 21, 9:26 pm, socratus <[email protected]> wrote: > 1. > In physics, a black body is an idealized object that absorbs all > electromagnetic radiation that falls on it. No electromagnetic > radiation passes through it and none is reflected. Because no > light (visible electromagnetic radiation) is reflected or > transmitted, > the object appears black when it is cold. However, a black body > emits a temperature-dependent spectrum of light. This > thermal radiation from a black body is termed black-body radiation. ># > Studying the laws of the black body historically led to quantum > mechanics > # > Blackbody radiation is light in thermal equilibrium, light radiation > with > a given temperature. It is the basic thermodynamic state of light. > Because > light is the oscillation of a continuous electromagnetic field, the > study > of blackbody radiation reveals how continuous fields can have a > temperature, something which contradicts classical physics. Because > the thermal state of light was so confusing before the advent of > quantum mechanics, the 19th century arguments that light has a > thermal equilibrium state were made very carefully. > # > Today the black-body cavity may be thought of as containing a gas of > photons > # > An almost perfect black-body spectrum is exhibited by the > cosmic microwave background radiation., Hawking radiation is the > hypothetical black-body radiation emitted by black holes. > !!! > # > Super black is an example of such a material, made from a > nickel-phosphorus alloy. More recently, a team of Japanese scientists > discovered a material even closer to a black body, based on > single-walled carbon nanotubes (SWNTs), which absorbs between > 97% and 99% of the wavelengths of the light that hits it. > > http://en.wikipedia.org/wiki/Black_body > > 2. > Max Laue (who won the Nobel Prize in Physics in 1914 ) > called the model of a black body as the ‘ Kirchhoff's vacuum.’ > 3. > And I have naive question: > Can a ideal black body be model of real Vacuum T= 0K ? > ========== . --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Epistemology" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/epistemology?hl=en -~----------~----~----~----~------~----~------~--~---
