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Do We Live In a Giant Cosmic Bubble?
Khemisty writes "Earth may be trapped in an abnormal bubble of space-time that is particularly void of matter. Scientists say this condition could account for the apparent acceleration of the universe's expansion, for which dark energy currently is the leading explanation.
Until now, there has been no good way to choose between dark energy or the void explanation, but a new study outlines a potential test of the bubble scenario.
If we were in an unusually sparse area of the universe, then things could look farther away than they really are and there would be no need to rely on dark energy as an explanation for certain astronomical observations.
'If we lived in a very large under-density, then the space-time itself wouldn't be accelerating,' said researcher Timothy Clifton of Oxford University in England. 'It would just be that the observations, if interpreted in the usual way, would look like they were.'"
No. The gravitational forces required for time dilation to be that strong are many orders of magnitude stronger than what you'll find on the galactic scale.
At least as far as gas and dust are concerned. The Standard Model explanation is that a 'nearby' star (the pulsar Geminga) went supernova a good long time ago, and blasted a large bubble (300 ly across) of relatively gas and dust free space, called 'the Local Bubble', and our solar system is well within this bubble. The relationship between that and what is being discussed I do not know, for details haven't been provided even on such things as scale. Do a search on 'Local Bubble' and you will find a great deal of information about this.
There's an unexplained anisotropy in the cosmic microwave background. Hot and cold spots don't appear to be quite randomly distributed. Nobody's come up with a good explanation, and it might be an instrumentation error or due to some local gravitational anomaly - say, lensing around the next supercluster over - but at the moment it's very unclear.
Real Daleks don't climb stairs - they level the building.
There would definitely be significant time dilation in close proximity to said black holes, but beyond even a fraction of a light year it would become negligible due to the rate at which gravitational force weakens.
* Q
P.S. If you don't get this note, let me know and I'll write you another.
This is no harder than believing in dark matter and dark energy, and it's before breakfast
"Time is an illusion, lunchtime doubly so". -The Hitchhiker's Guide to the Galaxy
Free Martian Whores!
I thought it was for deciding between two or more competing theories. I didn't think it could be used to reject all theories. If you have two theories, one makes two assumptions, one makes just one, it's more likely to be the one that just makes one. While both may be wrong, you can't use Occam's razor to throw BOTH of them out.
Furthermore, you don't use it at all, or if you did, you forgot to tell us the outcome. You actually just say both sound like deus ex machina, are both silly, and we're not right yet. Didn't even mention any underlying assumptions. That's not Occam's razor, or even rational argumentation. You just have a gut instinct that they're both wrong.
that would slow down time in the area.
The point is, no, it would not, not to the degree you are thinking of. Look, we do know what a galaxy is! We know there's a lot of mass in there! And it's easy to calculate the time dilation it causes, and it is negligable.
The observable universe is actually more like 96billion light years across, its a common mis-conception that because its 13.7 billions years old, its 27billion light years wide. This would b true if space was flat, but on cosmological scales, its highly curved.
The lower bound on the size of the universe, based on the CMBR is 78billion light years, any smaller, and then light would have circumnavigated it since the big bang, and we would see multiple images in the CMBR
http://en.wikipedia.org/wiki/Observable_universe
"The space elevator will be built about 50 years after everyone stops laughing." - Arthur C. Clarke ~1980