Quantum Theory cannot hurt you.
   - A guide to the universe.
   by Marcus Chown.

   Amazon review august 23rd. 2009.

   ----

   Lots of things about the universe
are not discovered yet, not explored yet, not identified yet, or not ascertained yet.
   But some things are. 
   And in this remarkable little book Marcus Chown gives us
some of the things that we do know. There are many books out there on
quantum theory and relativity, but few gives the facts in 
a popular form, without too much detail. And fewer still are also exciting, fresh, new
and precise at the same time - but somehow this book
accomplishes all these things. Thats cool.

  The subject matter is difficult though. Take an electron. It has an electric charge that
comes in two forms, positive and negative. What charge really >>is<< noone
really knows. 
  Light really is both wave and particles. It is like a coin
with two faces, where we can see either its wave like nature or its 
particle nature, but not both at the same time. So what
light really >>is<< is also an unknowable. The book goes into a lot
of the relativistic effects of based on the constant
speed of light. Travelling at speeds approaching
the speed of light is always fun. And highly confusing and thought provoking.
This book also gives us the twin paradox, where one twin on a spaceship 
ends up being younger than a stay at home twin. The faster you go, the slower you age.
  But if time almost stops if you come closer to the (the speed of) light,
then there is no time for light itself, and distances gets smaller (as speed comes
close to light speed), then for light itself there are no distances, or? 
  Also a real headbanger - and it would have been nice to seen
that explored some more in the book.  
   
  On it goes with quantum computers that uses resources of other universes
to give us a computation result? It is noted though that quantum 
computers are restricted to parallel calculations,
that output only a single answer - and it will be difficult to
state any calculation this way. So good old classical computers
will be here for some time. Still...
   Then there is quantum entanglement. Wonderful stuff. The
intermingling of two or more microscopic particles so that they lose
their individuality and in many ways behave as a single entity. But hey,
all the particles of the universe were once in the same state, together
back in the Big Bang - and are therefore to some extend 
entangled with each other. Noone knows what it means. But talk about
never being alone...
   And that Big Bang thing - as Jostein Garder (Sophies World) says,
A white rabbit being pulled out of a top, because it is
an extremely large rabbit, the trick takes billions of years....
   Not all is well in Big Bang land though, and we add
a little inflation theory plus dark matter to make it right. Kind of. 
   And then there is all the physics you know, but somehow
chose to ignore. As, we never see things as they are, but as they once
were. Distant stars and galaxies, the person standing next to us
(We see them as they were a billionth of a second earlier, 
something are brains cant pick up on, still).
   And the physics you dont know - as when approaching a singularity
in space (say a black hole). Slight irregularities in distribution
of matter in space(time)  will become ever more magnified,
and eventually chaotic. Warped spacetime will vary wildly depending on
direction, and eventually shatter, splitting into droplets,
"before" and "after" will loose all meaning, as will "distance"
and "direction" ... or ? 
   We need more answers ! :-)

   But a wonderful book to remind us where we live.


Aug 23rd. 2009

-Simon

Simon Laub

www.simonlaub.net