The Big Bang glow suggests that the universe is funnel-shaped

Is the shape of the universe like an ancient horn? This may sound like a surreal dream, but Frank Steiner of Ulm University in Germany claims that observations suggest that the shape of the universe is like a long mouthpiece, with one end narrow and the other end widening. Also this means that space is finite

Is the shape of the universe like an ancient horn? This may sound like a surreal dream, but Frank Steiner of Ulm University in Germany claims that observations suggest that the shape of the universe is like a long mouthpiece, with one end narrow and the other end widening. Also this means that space is finite.

This strange model may explain two pieces of observational evidence that confound cosmologists. The first is the pattern of hot and cold regions in the cosmic background radiation, which gives us a glimpse into the universe just 380,000 years after the Big Bang.

This pattern was accurately mapped in 2003 by NASA's WMAP (Wilkinson Microwave Anisotropy Probe) satellite. The WMAP found that the pattern has disappeared at the largest scale: there are no clear patches of hot and cold areas.

Steiner and his group claim, a final funnel-shaped reconstruction is consistent with the observations. It just doesn't have enough space to accommodate large areas.

According to their model, the volume of the universe today is about ten to the power of 23 cubic light years. When the universe was only 380,000 years old, it was a fraction smaller than it is today, too small to allow for large fluctuations in temperature.

In this model, called Picard Topology, the universe curves in a strange way. One end is infinitely long, but it is so narrow that its volume is finite. At the other end, the funnel expands, but not forever - if you could fly towards the expanding end in a spaceship, at some point you would find yourself flying back in on the other side of the beam (see diagram).

Funnel-like models have long been proposed in the 1990s to resolve a similar divergence, observed by the CubeSat (COBE) satellite. Steiner's group is the first to show that this idea fits the information from the WMAP. In 2003 another group claimed that the universe is finite.

In this group's model, space has the shape of a football, but this model ran into difficulties. It should have left a clear signal in the microwave radiation - an array of circles, which mirror each other's speckle pattern - but apparently, these circles do not exist.

The funnel model is harder to dismiss that way. He too would have left corresponding circles, but their pattern depends on the part of the horn where we are. "The research we published on the matching circuits apparently does not rule out the Picard topology," says Neil Cornish of the University of Montana in Bozeman.

The Picard topology model has another advantage. Assuming that space is flat, as conventional cosmology says, the smallest spots in the microwave radiation must be round. But they are not round. "If you look at the smallest structures, they look like little ovals," Steiner says. The curvature of the universe in the shape of a funnel can explain this. If you look at any small part of the funnel, it is saddle-shaped, like a Pringles chip bar - curving down in one direction and curving up in the direction perpendicular to it. The universe with this negative curvature will act as a wrapped lens and make us see the primordial round spots as ovals. Mathematicians can construct an infinite number of different types of space with negative curvature, most of which have one or more rays, and many of these models will match the observations. The Picard topology, on the other hand, is the simplest form.

The model would force scientists to abandon the "cosmological principle", which holds that all parts of the universe are roughly the same. "If someone happens to find himself at the narrow end of the funnel, everything will seem very strange to him, since there are only two tiny dimensions," says Holger Tan, a member of Tsot.

At a far enough point, you will be able to see the back of your head. It would be an interesting place to explore - but apparently, we are too far from the narrow end of the funnel to explore it with our telescopes.

However, the two most important observations are still inconclusive, and may just be statistical aberrations. Over the next year, the WMAP and other experiments will test whether large disturbances are really not found and whether the small ones are really elliptical.

If they do exist, the curvature of our universe is like that of Pringles, its shape is like a funnel and it is named after a character in "Star Trek". Reality surpasses all imagination.
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