Astronomers Find Huge Hole in Universe

realwx writes "Astronomers are surprised by a recent discovery of a space hole that is nearly a billion light years across. "Not only has no one ever found a void this big, but we never even expected to find one this size," said researcher Lawrence Rudnick of the University of Minnesota. Rudnick's colleague Liliya R. Williams also had not anticipated this finding. "What we've found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the universe," said Williams, also of the University of Minnesota.""

Comments

More info here

[Mr Europe]

Now this is *big* news ! The scientific world is waiting for good explanations.

More info here (with pictures..)
http://www.nrao.edu/pr/2007/coldspot/index.shtml

Re:More info here

[Randomly]

Here's a link to the original paper:

http://xxx.lanl.gov/PS_cache/arxiv/pdf/0704/0704.0 908v2.pdf

Re:More info here

[mikael]

I'm confused on one point. (This is not a flame). Why would photons going through a void lose energy?

The energy of a photon is directly proportional to the frequency and inversely proportional to the wavelength.

Photoelectric effect

Shorter wavelengths of a photon (ultra-violet, X-rays, Gamma rays) have more energy than longer wavelengths (visible light, infra-red).

Photons that we see from distant parts of the universe become affected by red-shift - anything moving away from us ends up with a longer wavelength that we would have seen if it were stationary. But this can also be caused by gravititional effects (time dialation causes by massive objects).

If the object is moving towards us, then the photos become affects by blue shift.

When a spiral galaxy is observed, the side moving towards the observer will have a slight blue shift, because the photon wavelength has been decreased.

The photons in the void must be getting a longer wavelength somehow - perhaps the spacetime continuum is expanding more there than it is where there is ordinary matter.

Re:its the center of the big bang

[Jugalator]

Yep, and if that gives one a big "huh!" look, the idea is that space expands by increasing the distance between matter, "stretching" spacetime itself, and doesn't expand inside something. There is no "something" on the outside, not even vacuum, because vacuum is a lack of matter, not a lack of spacetime. So it's a bit like a surface of a balloon expanding if you blow it up (= big bang), and wherever you go on that surface, you are always at the "center" from your point of view.

Re:Maybe

[osu-neko]

No, it's completely wrong.

Every point in the universe today is where the Big Bang occurred. You can see it right now. Just look around you.

Understand that space itself expanded from the starting point. All points of space in the universe today where infinitely closer together 13.7 billion years ago. The Big Bang did not expand outward into a mostly empty universe. The Big Bang occurred in a universe that was entirely full of extremely dense matter. As space expanded, the matter became less packed. You get the idea...

Re:Repeat after me ...

[shawn(at)fsu]

Actually the article said it was devoid of "dark matter", they freely admit they have no idea what this void is.

Re:Big Bang Start Point ???

[eddy the lip]

Yes, but you are also sitting at the start point of the big bang. Every spot in the universe can make the same claim. "Big bang" is a cool name for it, but it's a bit of a misnomer, as there wasn't anywhere for an actual explosion to occur when it happened. Thinking of the big bang as having a point of origin is a bit like asking "what's outside the universe?" Just as with Oakland, there's no there there. I'd recommend Brian Green's The Elegeant Universe. It's focus is string theory, but to get there you have to go through relativity, the big bang theory and quantum mechanics, as they're all related. He's a gifted science writer and ties it all together in a very accessible way.