Conventional material removal of BK7 optical glass will normally result in brittle fracture at the surface, generating severe subsurface damage and poor surface finish. Subsurface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. However, through ductile mode grinding it is possible to reduce the surface and subsurface cracks. It is m...

Underground nuclear explosions trigger significant earthquake activity for at least 32 hours afterward and to distances up to at least 860 kilometers. The proposed Amchitka test may be used to study the feasibility of employing high-yield underground nuclear explosions to release stresses accumulating in the lithosphere. Periodical explosions along active fault zones may be used to prevent disa...