Class 9:  Niels Bohr

Readings - Articles

• • "Bohr and Einstein": From Chapter 11 of "Niels Bohr’s Times, in Physics, Philosophy and Polity" by Abraham Pais; Clarendon Press, Oxford, 1991 (4+ pages); to view or download, click here.  

  • Physics Today, October 1985. "Niels Bohr, the man" by John Archibald Wheeler (6 pages); to view or download, click here.    

  • Physics Today, October 1985. "Niels Bohr, the quantum and the world" by Victor Weisskopf (2 pages); to view or download, click here. 

Readings - Biographical

• • Niels Bohr 1885 - 1962;  PBS - a brief biography of Bohr; to view, click here. 

  • Niels Bohr;  University of Copenhagen - Niels Bohr Institute: biography from childhood to the final years; to view, click here. 

Points to Ponder

• Quantum mechanics deals with phenomena on a much, much smaller scale than our everyday macroscopic world.  The tools we have for constructing a quantum-mechanical model are based on our macroscopic world. Can we expect that to give an accurate picture (think of the story of the blind men describing an elephant)?  

• An atom appears to be mostly empty space, its nucleus being 100,000 times smaller in diameter than the atom. Does it make sense to you that you’re sitting and standing on materials composed of atoms like that?

• Does it help you to try to understand an atom by visualizing it as a sun-and-planets system?

• “Theoretical constructions of science have no value unless they are supported by facts”. Agree or disagree? What are “facts” and how would they be arrived at? Can you think of any theories not based on facts? 

• Einstein is quoted as saying: “it is quite wrong to try founding a theory on observable magnitudes alone. In reality, the very opposite happens. It is the theory that decides what we can observe.” Do you agree or disagree? Why? Can you think of any example to support your viewpoint?

Optional Reading and Viewing

For other reading and viewing, click on Of Further Interest - Bohr.