Complexity at large

✍ Scribed by Leigh Tesfatsion; Dan Ashlock

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 97 KB
• Volume: 4
• Category: Article
• ISSN: 1076-2787
• DOI: 10.1002/(sici)1099-0526(199901/02)4:3<3::aid-cplx1>3.0.co;2-l

✦ Synopsis

Weeks (freelance geometer, Canton, N.Y.) explain why this is not so and go on to outline a plan for directly measuring the shape of the universe. The intent is to use the cosmic microwave background to directly measure the topological type of the universe. The article outlines some very strange possible shapes for the universe.

The Cosmic Background Explorer (COBE), orbited in the early 1990s, detected minute variations in the cosmic microwave background, an echo of the big bang. These variations represent density ripples that seeded the formation of the current universe of stars and galaxies. However, the detected variations were not detailed enough to permit mathematical deduction of the shape of the universe.

Cornish and Weeks propose to perform such a deduction by using better data, to be gathered by NASA's Microwave Anisotropy Probe (MAP) and by the ESA's Planck Explorer early in the twenty-first century. By looking for patterns of variation in microwave anisotropy along circles in the sky that repeat from one circle to another, it is possible to pin down the topological type of the universe. Some patterns of identical circles correspond to an infinite universe. Others imply a universe that wraps back on itself in one or another curious fashion. This attempt to directly measure the shape of the universe is a beautiful application of basic topological principles.

For more information on the various cosmic background measuring tools, try: