Einstein: His Life and Universe

18

. More specifically, Schrodinger’s equation shows the rate of change over time of the mathematical formulation of the probabilities for the outcome of possible measurements made on a particle or system.

19

. Einstein to Erwin Schrodinger, June 19, 1935, AEA 22-47.

20

. I am grateful to Craig Copi and Douglas Stone for helping to compose this section.

21

. Einstein to Erwin Schrodinger, Aug. 8, 1935, AEA 22-49; Arthur Fine, “The Einstein-Podolsky-Rosen Argument in Quantum Theory,”

Stanford Encyclopedia of Philosophy

, plato.stanford.edu/entries/qt-epr/. Note that Arthur Fine uncovered some of the Einstein-Schrodinger correspondence. Fine, chapter 3.

22

. Erwin Schrodinger to Einstein, Aug. 19, 1935, AEA 22-51.

23

. Erwin Schrodinger, “The Present Situation in Quantum Mechanics,” Nov. 29, 1935, www.tu- harburg.de/rzt/rzt/it/QM/cat.html.

24

. Einstein to Erwin Schrodinger, Sept. 4, 1935, AEA 22-53. Schrodinger’s paper had not been published, but Schrodinger included its argument in his Aug. 19, 1935, letter to Einstein.

25

. en.wikipedia.org/wiki/Schrodinger’s_cat.

26

. Einstein to Erwin Schrodinger, Dec. 22, 1950, AEA 22-174.

27

. David Bohm and Basil Huey, “Einstein and Non-locality in the Quantum Theory,” in Goldsmith et al., 47.

28

. John Stewart Bell, “On the Einstein-Podolsky-Rosen Paradox,”

Physic

1, no. 1 (1964).

29

. Bernstein 1991, 20.

30

. For an explanation of how Bohm and Bell set up their analysis, see Greene 2004, 99–115; Bernstein 1991, 76.

31

. Bernstein 1991, 76, 84.

32

.

New York Times

, Dec. 27, 2005.

33

.

New Scientist

, Jan. 11, 2006.

34

. Greene 2004, 117.

35

. In the decoherent-histories formulation of quantum mechanics, the coarse graining is such that the histories don’t interfere with one another: if A and B are mutually exclusive histories, then the probability of A or B is the sum of the probabilities of A and of B as it should be. These “decoherent” histories form a tree-like structure, with each of the alternatives at one time branching out into alternatives at the next time, and so forth. In this theory, there is much less emphasis

on measurement than in the Copenhagen version. Consider a piece of mica in which there are radioactive