Futurismic

We may be in a bubble:

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.

…

“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.”

One reason why this theory still isn’t widely accepted:

One problem with the void idea, though, is that it negates a principle that has reined in astronomy for more than 450 years: namely, that our place in the universe isn’t special.

When Nicholas Copernicus argued that it made much more sense for the Earth to be revolving around the sun than vice versa, it revolutionized science.

Since then, most theories have to pass the Copernican test. If they require our planet to be unique, or our position to be exalted, the ideas often seem unlikely.

This is obliquely tied to the problem of the apparent un-arbitraryness of our universe: a key scientific and philosophical problem for the 21st Century – why is it that the universe seems to be conveniently set up for life.

[via Slashdot][image from Jeff Kubina on flickr]

If this doesn’t boggle your mind, your mind is un-boggleable (Via Space.com):

Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can’t be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon “dark flow.” The stuff that’s pulling this matter must be outside the observable universe, researchers conclude.

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A theory called inflation posits that the universe we see is just a small bubble of space-time that got rapidly expanded after the Big Bang. There could be other parts of the cosmos beyond this bubble that we cannot see. In these regions, space-time might be very different, and likely doesn’t contain stars and galaxies (which only formed because of the particular density pattern of mass in our bubble). It could include giant, massive structures much larger than anything in our own observable universe. These structures are what researchers suspect are tugging on the galaxy clusters, causing the dark flow.

“The structures responsible for this motion have been pushed so far away by inflation, I would guesstimate they may be hundreds of billions of light years away, that we cannot see even with the deepest telescopes because the light emitted there could not have reached us in the age of the universe,” Kashlinsky said in a telephone interview. “Most likely to create such a coherent flow they would have to be some very strange structures, maybe some warped space time. But this is just pure speculation.”

Even though I was a teenager in the 1970s, I don’t say this very often, but…far OUT!

And I mean that literally.

(Image: Wikimedia Commons.)

[tags]cosmology, Big Bang, astronomy, outer space[/tags]

Worth a spin; has considerable charm.

(Well, I tried to embed the video, but this link will take you to it on YouTube)

Large Hadron Rap

[ATLAS particle detector experiment; Image Editor]

The June 2008 issue of Scientific American sets out to answer a very perplexing question:

Why does time only move forward?

To find the answer, according to Sci-Am and Mr. Sean M. Carroll, we have to start looking at a very unlikely place:

To account for it, we have to delve into the prehistory of the universe, to a time before the big bang. Our universe may be part of a much larger multiverse, which as a whole is time-symmetric. Time may run backward in other universes.

The article is filled with high-end physics and a bit of science jargon, but Mr. Caroll puts uses neat little analogies to explain difficult concepts:

The asymmetry of time, the arrow that points from past to future, plays an unmistakable role in our everyday lives: it accounts for why we cannot turn an omelet into an egg, why ice cubes never spontaneously unmelt in a glass of water, and why we remember the past but not the future. And the origin of the asymmetry we experience can be traced…back to the orderliness of the universe near the big bang. Every time you break an egg, you are doing observational cosmology.

All in all, it’s a very interesting article and well worth a read. Some of the concepts used in the article are highly science fictional and are prime idea fodder for stories about multiverses and time travel. In fact, for those who’ve read River of Gods, may recognize the inspiration for ideas in that novel presented in this article. [image by gadl]

Israeli scientists have sliced electrons into “quasiparticles,” each with a quarter charge of the electron.

Although electrons are indivisible, if they are confined to a two-dimensional layer inside a semiconductor, chilled down to a fraction of a degree above absolute zero and exposed to a strong magnetic field that is perpendicular to the layer, they effectively behave as independent particles, called quasiparticles, with charges smaller than that of an electron.

Quasis have been known for 20 years, but they were “odd fractionally charged” — one third of an electron, one fifth, etc. The quarter-charges behave differently and may be useful for computing.

Those of us who have trouble wrapping our heads around quantum stuff might sympathize with astronomers, who, the New York Times tells us, are finding cosmology just as puzzling.

As far as astronomers can tell, there is no relation between dark matter, the particles, and dark energy other than the name, but you never know.

Nevertheless, string theorist Brian Greene, promoting the World Science Festival, reminds us of something most readers of this site would probably find a truism, but is probably a new idea to a lot of people:

We must embark on a cultural shift that places science in its rightful place alongside music, art and literature as an indispensable part of what makes life worth living.

[Ella Delivers Her Lecture on String Theory by Phillip C]