Technical p r o g r e s s is l a rge ly determined by the creat ion of new ma te r i a l s with special physical p ro pe r t i e s sui table for se rv ice under ex t reme conditions. Such requi rements have led to the acce le ra ted development of h igh -p re s su re technology, the use of which in physical r e s e a r c h has, in turn, had an important effect on theoret ica l questions of the s t ruc ture of mat ter .