European physicists say some stars could contain wormholes, tunnel-like passages connecting distant points in space-time, a concept sparking much debate.

Physicist Vladimir Folomeev in the Kyrgyz Republic and his colleagues suggest pairs of stars could be joined by wormholes full of an exotic material known as "phantom matter," ScienceNews.org reported Friday.

Strictly hypothetical, phantom matter has been put forward as a possible explanation for the accelerating expansion of the universe, and its exotic properties -- if it even exists -- could also enable a wormhole to be kept propped open, Folomeev and his colleagues say.

They have come up with a preliminary mathematical model suggesting the possible existence of such a phenomenon but acknowledge their analysis isn't complete.

Other scientists aren't quite ready to buy the idea.

"It's a nice piece of speculative work, but it is speculation," says theoretical physicist Matt Visser of Victoria University of Wellington in New Zealand.

"I am pretty sure that once you admit exotic matter of some suitable kind, you can mathematically construct a star with a wormhole inside," says relativity theorist Dieter Brill of the University of Maryland in College Park.

For now, this is just an idea that still must be refined by further calculations, Folomeev says.

earlier related report
Satellite completes gravity 'map' of Earth
Paris (UPI) Mar 4, 2011 - The European Space Agency says a satellite has completed the ambitious goal of a complete mapping of Earth's gravity with unprecedented precision.

The Gravity field and steady-state Ocean Circulation Explorer satellite, launched in March 2009, has collected the measurements needed to record the "geoid" reference shape of our planet, an ESA release said Friday.

The geoid is the shape of an imaginary global ocean dictated by gravity in the absence of tides and currents and is a crucial reference for accurately measuring ocean circulation, sea-level change and ice dynamics -- all affected by climate change, researchers say.

"The satellite has recorded the measurements necessary to enable us to produce a high-resolution map of the 'geoid' that is far more accurate and has a much higher spatial resolution than any other dataset of this kind," Volker Liebig, director of ESA's Earth Observation Programs, said.

In the coming weeks the data will be calibrated and processed for scientists to create a unique model of the geoid.

"Once the gravity models are completed, they will be made available to all users, free of charge in line with ESA's data policy," GOCE Mission Manager Rune Floberghagen said.