Geometry and Destiny

The recognition that the cosmological constant may be non-zero forces us to re-evaluate standard notions about the connection between geometry and the fate of our Universe. An open Universe can recollapse, and a closed Universe can expand forever. As a corollary, we point out that there is no set of cosmological observations we can perform that will unambiguously allow us to determine what the ultimate destiny of the Universe will be.Comment: 7 pages, Gravity Research Foundation Essa

Japan's new security agenda

New Japanese Prime Minister Shinzō Abe has only been in office since late September, but already the outlines of his administration are becoming clearer, both in expected and unexpected directions. Abe’s administration is proving to be conservative and revisionist, and even more so than that of his predecessor Junichirō Koizumi. Abe has certainly moved to improve ties with China and South Korea—Beijing and Seoul the October destinations for his first overseas visits within two weeks of taking power—and thereby to limit the damage wrought by Koizumi’s visits to Yasukuni Shrine and bilateral wrangling over Japan’s colonial history. However, the general thrust of Abe’s diplomacy is built upon much of the legacy left by Koizumi, and is attempting to shift it on to a yet more pro-active and assertive path

The Cosmological Constant is Back

A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted value for the cosmological constant corresponds to a very tiny vacuum energy density. We discuss future observational tests for a cosmological constant as well as the fundamental theoretical challenges---and opportunities---that this poses for particle physics and for extending our understanding of the evolution of the Universe back to the earliest moments.Comment: latex, 8 pages plus one ps figure available as separate compressed uuencoded fil