In physics, a black body is an idealized object that absorbs all electromagnetic radiation falling on it. Blackbodies absorb and re-emit radiation in a characteristic pattern called a spectrum. They emit light incandescently, which means they radiate a continuous spectrum of light. 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. In the blackbody spectrum, the shorter the wavelength, the higher the frequency, and the higher frequency is related to the higher temperature. Thus, the color of a hotter object is closer to the blue end of the spectrum and the color of a cooler object is closer to the red.
At room temperature, black bodies emit mostly infrared wavelengths, but as the temperature increases past a few hundred degrees Celsius, black bodies start to emit visible wavelengths, appearing red, orange, yellow, white, and blue with increasing temperature. By the time an object is white, it is emitting substantial ultraviolet radiation.
The term “black body” was introduced by Gustav Kirchhoff in 1860. When used as a compound adjective, the term is typically hyphenated, as in “black-body radiation”, or combined into one word, as in “blackbody radiation”
Black-body emission gives insight into the thermal equilibrium state of a continuous field. In classical physics, each different Fourier mode in thermal equilibrium should have the same energy. This approach led to the paradox known as the ultraviolet catastrophe, that there would be an infinite amount of energy in any continuous field. Black bodies could test the properties of thermal equilibrium because they emit radiation which is distributed thermally. Studying the laws of the black body historically led to quantum mechanics.
All matter originates and exists only by virtue of a force. We must assume behind this force the existence of a conscious and intelligent Mind. This Mind is the matrix of all matter.
Max Planck
Nobel Prize in Physics in 1918 and one of the fathers of the Quantum Theory
(via apfsampaio)
(via apfsampaio)
Soren Kierkegaard.
I guess hindsight really is 20/20, right, Soren? Btw…the same is true about quantum mechanics…
