On Fri, 16 Mar 2012 06:48:23 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
:

The last I read they were
theorizing about inter molecular adhesion and wondering about how to
prove it :-)



The last I heard, they had solved it.

According to what I read, it functions by the same method Gecko feet do --
by having structures so small or close together that atomic binding forces
come into play.

The last I read - years ago - was the attraction theory seemed to be
about all that was left after the other ideas had been proved wrong,
but at the time no one had demonstrated any definitive proof of the
theory..... but they were still working on it :-)

Here is an abstract of the modern theory:

A method is presented for calcg. van der Waals forces in systems with
nonlocal cond. The fluctuating fields in the electromagnetic stress
tensor are obtained by applying the fluctuation-dissipation theorem to
the response of the system to an external polarization. As an example,
the method is used to calc. the contribution of conduction electrons
to the interaction of 2 blocks of metal. When the electrons are
described in a simple hydrodynamic approxn. keeping only the lowest
order nonlocal terms, the interaction force is the same as that
obtained by Lif****z assuming local cond. At sepns. large compared to
the London penetration depth c/wp the interaction is due to
electromagnetic waveguide, modes, while at distances small compared to
c/wp, the force is due to surface plasmons. As a 2nd example, the
method is applied to the interaction of 2 graphitelike blocks. With a
quantum mech. derived description of the electron motion, the
resulting force differs from Lif****z expression both because of the
anisotropy of the system and because of the nonlocal cond.



By the way, machining all those tiny gecko feet is going to be a
bitch.
--
Cheers,

John B.