ISSYP 2012

The world's most ambitious scientific experiment is buried 100 meters underground, straddling Switzerland and France.  A billion times every minute, the Large Hadron Collider (LHC) slams together protons, while four giant detectors watch closely.

 So how does the Large Hadron Collider work?  Why can slamming tiny particles into each other provide clues about the nature of all space and time?  What mysteries are physicists trying to solve with data from the LHC, and what is the Higgs anyway?  What might we learn next? How does the cutting edge of particle physics relate to the world around us, from the patterns of stars in the sky to the fact that they shine at all?

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 


So how
does the Large Hadron Collider work?  Why
can slamming tiny particles into each other provide clues about the nature of
all space and time?  What mysteries are
physicists trying to solve with data from the LHC, and what is the Higgs
anyway?  What might we learn next? How
does the cutting edge of particle physics relate to the world around us, from
the patterns of stars in the sky to the fact that they shine at all?

Just as there is a
difference between knowing how to *drive* a car and understanding its
functioning well enough to fix it when it breaks down, so too is there a
difference between knowing how to *use* quantum theory to make
predictions and understanding what it says about the world well enough to see
how it might fail or how it might be usefully generalized. The field of quantum
foundations seeks to achieve such a deeper understanding. In particular, it
seeks to determine the correct interpretation of quantum theory and to find the
principles underlying it, questions for which there is still no consensus among
researchers.  In this talk, I’ll discuss some of the interpretational
problems of quantum theory and several of the most prominent proposals for how
to overcome these problems.  The list includes introducing hidden
variables that we must necessarily remain uncertain of, changing the rules of
logic, and positing the existence of an infinite number of parallel worlds.

For the first time in human thought it is now
possible to observationally determine how much matter is in the Universe as a
whole. These observations strongly support the “Concordance Model” of Hot Big
Bang Cosmology, and reinforce earlier indications that ordinary matter (atoms,
nuclei and electrons) make up at present at most 4% of the total of the
Universal energy density. The big surprise was that the rest consists of *two*
kinds of unknown forms of matter: the so-called Dark Matter and Dark Energy.
This talk summarizes for non-specialists the various lines of evidence for
their existence, and some of the theoretical ideas which have been proposed to
account for their properties