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el final de la materia?




        Uhh... vaya, asi que no hay evidencia de que los quarks 
esten formados por particulas mas elementales. Seria curioso averiguar
como empezaron estos rumores. Aunque a lo mejor nunca empezaron; la
idea de que los quarks estan formados por sub-quarks, formados por
sub-sub-quarks, etc, parece existir desde hace mucho.
	Sacado de sci.space.news :

QUARKS ARE POINTLIKE AT THE 10**-19 METER LEVEL.  
Quarks, along with leptons, are the most elementary
things in the universe, as far as experiments can tell.  If quarks,
which are the constituents of protons and neutrons, had
constituents themselves, how would we know?  One way is to
smash quarks together and see what flies out.  Physicists at
Fermilab smash protons (which can be thought of as delivery
vehicles for quarks) and antiprotons with one another and look at
the outgoing jets of debris particles. Previously (Update 258) an
excess of events with high-energy jets shooting away from the
interaction at large angles was interpreted by some (although not
by the experimentalists themselves) as possible evidence for
subquarks.  The latest word on the situation, as reported now by
the CDF collaboration, is that quarks do not have any apparent
structure.  One way of expressing this is to say that if objects are
hiding inside quarks, their energy would have to be greater than
about 1.6 TeV. A still more dramatic way of registering this null
result is to say that having trained their microscope on quarks,
the Fermilab scientists see no objects at the 10**-19--meter level,
the smallest distance scale inside quarks ever explored.  (F. Abe
et al., upcoming article on dijet angular distribution in Physical
Review Letters; contact Robert Harris at Fermilab,
rharris en cdfsga.fnal.gov; 630-840-4932.) A few other
experiments, such as those that search for proton decay, have in
effect probed even finer distance scales without finding any tiny
lurking things.