Universe on a T-Shirt: The Quest for the Theory of Everything by Dan Falk

Author:Dan Falk
Language: eng
Format: mobi, epub
ISBN: 9781611454604
Publisher: Arcade Publishing
Published: 2011-12-15T05:00:00+00:00

Niels Bohr, pictured here with Einstein, applied the principles of quantum theory to the hydrogen atom. Einstein, though skeptical of the new theory, also contributed to the quantum revolution with his discovery of the photoelectric effect.

The next step in the quantum revolution came with the work of the Danish physicist Niels Bohr (1885-1962). In 1913, Bohr, still a newcomer to the world of theoretical physics, applied the new quantum theory to the hydrogen atom. Hydrogen is the most abundant element in the universe and also the simplest; it consists of a single proton with a single electron circling around it. Bohr showed that the electron could only occupy orbits that had specific, discrete energy levels. (One might compare the electrons to people attending a concert in an auditorium, who may find themselves, say, in row 12 or row 13, but never row 12.5.) In this picture of the hydrogen atom, radiation is emitted only when the electron “jumps” from one energy level to another. The bigger the electron’s jump, the greater the energy of the photon released.

Bohr’s proposal was radical. It completely contradicted the ideas of Newton and Maxwell—but, as physicists were discovering, the classical framework needed to be overhauled in order to explain the workings of the atom. The new theory immediately showed its strength. First, it solved the problem of atomic stability; second, it described the spectrum of hydrogen with incredible precision. Indeed, the theory’s prediction of the locations of the various “peaks” in the hydrogen spectrum agreed with those seen in the laboratory to about one hundredth of one per cent. Later, the quantum hypothesis was applied to other elements with equal success—even allowing scientists to predict the properties of exotic chemicals not yet discovered. Awarded the Nobel Prize in 1922, Bohr is recognized alongside Planck and Einstein as one of the key players in the early development of quantum theory.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.