Understanding Quantum Physics: An Advanced Guide for the Perplexed

 
    Acknowledgements
    The idea of random
discontinuous motion of particles came to my mind when I was a postgraduate at
the Institute of Electronics, Chinese Academy of Sciences in 1993. I am happy
that finally it has a more logical and satisfying formulation in this book.
During the past twenty or so years, I have benefited from discussions with many
physicists and philosophers of physics who care about the way the world really
is. They are: Stephen Adler, Jacob Bekenstein, Samuel Braunstein, Jeremy
Butterfield, Tian Yu Cao, Zexian Cao, Philippe Eberhard, Bernard d' Espagnat,
Shelly Goldstein, Basil Hiley, Gerard 't Hooft, Sabine Hossenfelder, Chris
Isham, Frederick M. Kronz, Gui-Lu Long, Alwyn van der Merwe, David Miller,
Philip Pearle, Roger Penrose, Huw Price, Alastair Rae, Erasmo Recami, Dean
Rickles, Abner Shimony, Henry P. Stapp, George Svetlichny, Antoine Suarez,
Antony Valentini, Hans Westman, Christian Wüthrich, Heinz-Dieter Zeh, and Anton
Zeilinger, among others. I thank them all deeply.
    My deepest
gratitude goes to my parents, QingFeng Gao and LiHua Zhao, who spared no effort
to provide the best possible environment for me to grow up in and their
constant support during my extended studies. They have always allowed me to
have the freedom of choice, and for that I am truly grateful. Finally, I am
deeply indebted to my wife, HuiXia, and my daughter, Vicky, for their
unflagging love and support throughout my study and writing; this book would
have been impossible without them. Moreover, they have never let me forget the
true values of life.
    This book was
support by a University of Sydney International Scholarship and a Postgraduate
Scholarship in Quantum Foundations provided by the Unit for History and
Philosophy of Science and Centre for Time of the University of Sydney, as well
as by two Lucy Firth Scholarships in Philosophy provided by the Department of
Philosophy of the University of Sydney. I would like to thank them for their
kind support.
    Shan Gao Sydney
November 2011
     

 
    A True Story
of Quantum Exploration
    —An Excerpt from God Does Play Dice With the
Universe
    During
my childhood, it had been a wonder for me that the twinkling stars strewed in
the night sky don't fall to the Earth. I had a strong desire to know the whys
and wherefores. Later I found the answer in textbooks. It changed my picture of
the universe. When I was an undergraduate, I began to be entranced by the deep
mysteries of the atomic world. I was especially stunned by the fact that the
commonsense planetary picture of atoms turns out to be utterly false; the
electron in an atom cannot rotate round the atomic nucleus as the Earth rotates
round the sun, or else it would soon radiate its energy and fall into the
nucleus, and as a result, my body composed of atoms would collapse in a blink.
How does the electron move then? It must exist in the atom. It must move in
some way there. But more surprisingly, textbooks provided no picture of the
motion of the electron. On 22 August 1987, I wrote in my diary: "Is it
really true that we have no way to describe the atomic processes as processes
happening in space and time?" I could only search for the answer by
myself. Then I started on a lonely journey to "trace" the elusive
electron at the age of 16.
    In order to find
how the electron moves in an atom, I went to the Institute of Electronics,
Chinese Academy of Sciences to pursue my graduate study. But it was according
to expectation that nobody there could give me any tips either. I then spent
nearly every day in musing on the seemingly indescribable motion of electrons.
If a ball indeed moves in a continuous way, then it seems that an electron or
an atom should also move in the same way. The ball is composed of atoms after
all. But, on the other hand, if an electron moves continuously in an atom, it
will soon fall into the nucleus, while the tragedy does not happen in reality.
This is a great dilemma. I found some possible solutions, but they shortly
proved to be wrong.
    The puzzle had
been plaguing me. Day after day, I gradually doubted the reality of continuous
motion. But I still felt in my bones that the particles must move in some way.
Finally, in the early morning of 12 October 1993, I experienced a sudden
enlightenment. At that moment, I felt that my body permeated the whole universe
and I was united with it. I "disappeared". A clear picture then
appeared: a particle is jumping in a random and discontinuous way. It is