Universe 250x Bigger Than Visible Universe

[C1ay]

Cosmos At Least 250x Bigger Than Visible Universe, Say Cosmologists

The universe is much bigger than it looks, according to a study of the latest observations.

 

When we look out into the Universe, the stuff we can see must be close enough for light to have reached us since the Universe began. The universe is about 14 billion years old, so at first glance it's easy to think that we cannot see things more than 14 billion light years away.

 

That's not quite right, however. Because the Universe is expanding, the most distant visible things are much further away than that. In fact, the photons in the cosmic microwave background have travelled a cool 45 billion light years to get here. That makes the visible universe some 90 billion light years across.

 

That's big but the universe is almost certainly much bigger. The question than many cosmologists have pondered is how much bigger. Today we have an answer thanks to some interesting statistical analysis by Mihran Vardanyan at the University of Oxford and a couple of buddies...

 

More at http://www.technologyreview.com/blog/arxiv/26333/

[LaurieAG]

Hi C1ay,

 

That's not quite right, however. Bcause the Universe is expanding, the most distant visible things are much further away than that. In fact, the photons in the cosmic microwave background have travelled a cool 45 billion light years to get here. That makes the visible universe some 90 billion light years across.

 

There seems to be a great divide developing between cosmologists and astronomers.

 

http://www.google.com.au/search?q=%22Scientists+claim+earliest+galaxy+so+far,+480+million+years+after+Big+Bang%22&hl=en&lr=&prmd=ivns&ei=JBtJTcyXC4OGvgO1kK3sDw&start=20&sa=N

 

WASHINGTON - An international team of astronomers say they have glimpsed the earliest galaxy yet, a smudge of light from nearly 13.2 billion years ago — a time when the cosmos was a far lonelier place.

 

The research has not been confirmed, and some astronomers are skeptical. The new findings are based on an image from the Hubble Space Telescope and are published in Thursday's issue of the journal Nature. The scientists calculate the new-found galaxy dates to just 480 million years after the Big Bang.

 

That would trump last year's announcement by a French team who said they found a galaxy from about 600 million years after the Big Bang. That discovery also is not universally accepted and one of the skeptics is the co-author of the latest paper.

 

Even more interesting than the advanced age of the newly discovered galaxy is the absence of other similarly aged bright galaxies. That indicates that star formation during that point in the universe's early childhood was happening at a rate 10 times slower than it was millions of years later, said study co-author Garth Illingworth of the University of California Santa Cruz.

 

Illingworth described what the cosmos might look like at that time period when the universe was smaller and the stars bluer and dimmer.

 

"It wouldn't be nearly as interesting — a blob here, a blob there," he said in a phone interview.

 

But other astronomers have their doubts about this discovery.

 

Richard Ellis at the California Institute of Technology is troubled because Illingworth's team originally found three 13.2 billion-year-old galaxies and then withdrew their original study. The authors then came up with an entirely different galaxy, so all that switching "makes it difficult to believe," he said.

 

Illingworth said originally he and colleagues confused what may have been real light from billions of years ago and background "noise" from the process of looking so far away, so they re-did the study. He said they then found the new galaxy and saw that it was more likely to be real than the previous ones.