[U.S. Stock Market's Three Major Indexes Open Lower, Optical Communication Sector Leads Decline] According to Golden Finance, on October 8, the three major U.S. stock indexes opened lower, with the Dow Jones down 0.36%, the Nasdaq down 0.51%, and the S&P 500 down 0.37%. The optical communication sector led the decline, with Coherent dropping over 4%, and Corning, Lumentum, and Marvell Technology all falling over 3%.