Hard spheres are widely used as model particles in the statistical mechanical theory of fluids and solids.

Lipscomb's group developed calculation methods, both empirical and from quantum mechanical theory.

This is sometimes called the second "Einstein coefficient", and can be deduced from quantum mechanical theory.

Divers who understood mechanical theory were few and far between.

Investigators, however, say they are waiting to examine the airplane before ruling in or out any theories - mechanical or criminal.

A manuscript "Heat", tentatively dated between 1783 and 1790, describes a "mechanical theory of heat".

He developed a statistical mechanical theory for polymer mixtures there.

I just hate it when people try to reduce the spiritual world with purely mechanical theories -those behaviorists, for example.

His most important paper, On the mechanical theory of heat, published in 1850, first stated the basic ideas of the second law of thermodynamics.

However, Pascal went even further to test the mechanical theory.