October 11, 2003


Tantalising evidence hints Universe is finite (New Scientist, 08 October 03)

Perplexing observations beamed back by a NASA spacecraft are fuelling debates about a mystery of biblical proportions - is our Universe infinite? Scientists have announced tantalising hints that the Universe is actually relatively small, with a hall-of-mirrors illusion tricking us into thinking that space stretches on forever.

However, work by a second team seems to contradict this, and scientists are now busy trying to resolve the conundrum. "Whether space is finite is something people have been asking since ancient times, and probably before that," says mathematician Jeffrey Weeks from Canton, New York. "If we resolved this and confirmed that space is finite, this would be an enormous step forward in our understanding of nature."

At the centre of the debate are observations by NASA's Wilkinson Microwave Anisotropy Probe (WMAP), which was launched in 2001. The probe measures temperature ripples in the "cosmic microwave background", the afterglow radiation from the big bang fireball.

Astronomers are interested in how strong different sizes of ripples are, as this reveals vital information about the early Universe, and might tell us how big the Universe is today. Many astronomers suspect that the Universe is infinite.

In that case, the microwave background ripples should have an unlimited range of sizes. But while WMAP's observations of small-scale ripples have matched predictions for an infinite Universe almost perfectly, the large-scale measurements have not. On the largest scales, WMAP has shown that the ripples almost disappear.

The only thing in the Universe that is certainly infinite is our ignorance.

Universe is Finite, "Soccer Ball"-Shaped, Study Hints (Sean Markey, October 8, 2003, National Geographic News)

"What makes it exciting now is it's not a matter of idle speculation," said Jeffrey Weeks, a freelance mathematician in Canton, New York, and study co-author. "There's real data to look at and the possibility of getting a definite answer."

Weeks, recipient of a MacArthur Fellowship or so-called "genius award," arrived at the model with a team of French cosmologists while studying cosmic background radiation observed by NASA's Wilkinson Microwave Anisotropy Probe (WMAP).

It would be the French who came up with this.

Posted by Orrin Judd at October 11, 2003 7:22 AM

The French and the MacArthur Foundation. What a combo!

I thought everyone knew the universe is shaped like a hockey puck.

Posted by: Peter B at October 11, 2003 3:22 PM

We would know for sure the French came up with it if it were called the Wilkonson Infinity-testing Microwave Probe (WIMP).

Posted by: Jeff Guinn at October 12, 2003 7:43 AM

This would support OJ's theory that there could be a bunch of gods, each of whom got their own little Universe for XMass.

Posted by: David Cohen at October 12, 2003 7:25 PM

They have proposed that the universe is a dodecahedron. The shape is 12 sided and each side is a regular pentagon. The dodecahedron was used in antiquity to represent the entire universe, and Kepler used it also, both between the orbits of earth and Mars and also as the entire universe.

Posted by: Robert Schwartz at October 12, 2003 11:03 PM

Not quite infinite ignorance.

It is a mere trope of Orrin's that we don't know anything. He does not live his beliefs.

Posted by: Harry Eagar at October 13, 2003 6:38 PM

I do live mine--I believe faith is sufficient. I don't live yours--the belief that only reason can guide us. No one lives yours, in point of fact, everyone takes their own existence on nothing but faith.

Posted by: OJ at October 13, 2003 7:19 PM

Nothing but faith?

My wife placed a lot of importance in some other things when I got laid off last year.

Posted by: Jeff Guinn at October 13, 2003 9:51 PM