Deputy Defense Secretary Ash Carter listens to a brief from professor Seth Teller at the Massachusetts Institute of Technology's Lincoln Laboratory in Lexington, Mass., July 15, 2013. Deputy Defense Secretary Ash Carter listens to a brief from professor Seth Teller at the Massachusetts Institute of Technology's Lincoln Laboratory in Lexington, Mass., July 15, 2013. SHARE IMAGE: Download Image: Full Size (0.31 MB) Tags: Photo Essays Photo By: VIRIN: 365403-C-IPT99-355.jpg Photo Gallery