Re: Is it possible to shrink an elastic band? If so, how can it be done?

Hello!

"Elastic band" is something of a vague term.  If you mean what's commonly 
called a rubber band, I don't know of any particular way to shrink one. 
However, if you stretch your boundaries of  what you mean by "elastic 
band" a bit wider, you do find candidates.

Many plastics have elasticity in the scientific sense (i.e. the material 
can be deformed somewhat, not suffer permanent physical change, and return 
to its original shape).  Partially-reacted polymer formations are used to 
create what's called "shrink tubing" and "shrink wrap".  These can be used 
for electrical insulation or for attaching labels to things like ropes 
(shrink tubing), and for sealing just about anything into plastic (shrink 
wrap). Heating the material (with something like a hair dryer or...not too 
close...a candle flame) causes its polymerization to be completed. As this 
happens, the polymer units lock on to each other more tightly and thus the 
material shrinks in volume. At least some of these materials, when shrunk 
(the shrink tubing used on rope, e.g.) have enough flexibility
in them that they the general public might accept them as "elastic". Your 
Mad Scientist has used shrink tubing to attach identification labels to 
rescue ropes, and the rope still bends after the tubing is put on it.

I expect I've "cheated" on what you meant by "elastic band", but there it 
is. Never can trust these Mad Scientists...they're Mad, after all :-)

ADMIN NOTE:
So the answer to your question is "maybe" - I'd suggest trying a quick
experiment with a hair dryer and a rubber band.