The Universe

[Felicatra]

powerful space explosion may herald star's death by black hole

"a huge, powerful star explosion detonated in deep space last week — an ultra-bright conflagaration that has astronomers scratching their heads over exactly how it happened.

the explosion may be the death cry of a star as it was ripped apart by a black hole, scientists said. high-energy radiation continues to brighten and fade from the march 28 blast's location, about 3.8 billion light-years from earth in the constellation draco.

astronomers say they've never witnessed an explosion so bright, long-lasting and variable before, according to nasa officials.

the explosion looks like a gamma-ray burst — the most powerful type of explosion in the universe, which usually mark the destruction of a massive star — but the flaring emissions from these dramatic events never last more than a few hours, researchers said.

"we know of objects in our own galaxy that can produce repeated bursts, but they are thousands to millions of times less powerful than the bursts we are seeing now," said andrew fruchter, of the space telescope science institute in baltimore, in a statement today (april 7). "this is truly extraordinary."

http://www.space.com/11328-strange-s...lack-hole.html

[LightEye]

dear friends,

http://www.dailymail.co.uk/sciencete...hysicists.html

be well, be love.

david

early universe may have had one dimension not three... and now we know how to prove it, say scientists

by daily mail reporter
last updated at 9:28 am on 22nd april 2011

* theory suggests fourth spatial dimension set to open up as the universe expands

did the early universe have just one spatial dimension? that's the mind-boggling question at the heart of a theory scientists say they are on the brink of solving.

the theory was first proposed by physicist dejan stojkovic and colleagues from the university of buffalo in 2010.

they suggested that the early universe - which exploded from a single point and was tiny at first - was one-dimensional (like a straight line) before expanding to include two dimensions (like a plane) and then three, which is the world in which we live today.
the next stage? 3d tvs can give the optical illusion of three dimensions to a two dimensional screen. now scientists believe a fourth dimension could open up

the next stage? 3d tvs can give the optical illusion of three dimensions to a two dimensional screen. now scientists believe a fourth dimension could open up

the theory, if valid, would address important conundrums facing particle physicists.

now, in a new paper in physical review letters, dr stojkovic and colleagues have come up with a test that could prove or disprove the 'vanishing dimensions' hypothesis.

[LightEye]

desar friends,

http://plus.maths.org/content/space-chessboard

be well, be love.

david

is space like a chessboard?
by jennifer marcus

physicists at the university of california, los angeles (ucla) set out to design a better transistor and ended up with a discovery which suggests a new explanation of electron spin and may even lead to a new understanding of the nature of space.
electron spin and graphene

an electron in graphene hops from carbon atom to carbon atom as if moving on a chessboard with triangular tiles. at low energies the individual tiles are unresolved, but the electron acquires an internal spin quantum number which reflects whether it is on the blue or the gold tiles. thus the electron's spin could arise not from rotational motion of its substructure, but rather from the discrete, chessboard-like structure of space. (image: chris regan/cnsi)

space is usually considered infinitely divisible — given any two positions, there is always a position halfway between. but in a recent study aimed at developing ultra-fast transistors using a new material called graphene, researchers from the ucla department of physics and astronomy and the california nanosystems institute show that dividing space into discrete locations, like a chessboard, may explain how point-like electrons, which have no finite radius, manage to carry their intrinsic angular momentum, or spin.

while studying graphene's electronic properties, professor chris regan and graduate student matthew mecklenburg found that a particle can acquire spin by living in a space with two types of positions — dark tiles and light tiles. the particle seems to spin if the tiles are so close together that their separation cannot be detected. "an electron's spin might arise because space at very small distances is not smooth, but rather segmented, like a chessboard," regan said. their findings are published in the march 18 edition of the journal physical review letters.

[LightEye]

dear friends,

http://www.wired.com/wiredscience/20...no-cmb-circles

be well, be love.

david

theory of recycled universe called into question
by lisa grossman may 13, 2011 | 1:52 pm

in november, cosmologists claimed to see echoes of violent collisions that happened before the big bang in the form of circular patterns in the early universe’s relic radiation. but two new analyses of the same data, which are the first papers on the subject to be published in peer-reviewed journals, assert that those circles are nothing special.

“we found there was nothing strange in the [cosmic microwave background] data at all,” said astrophysicist ingunn wehus of the university of oslo, coauthor of a paper published online in the astrophysical journal letters may 9. the difference in their analyses, she says, is “we do it correctly, and they do not.”

the original claim, made in research published on arxiv.org by theoretical physicist roger penrose of the university of oxford in england and vahe gurzadyan of the yerevan physics institute and yerevan state university in armenia, made a small media splash (and was one of wired science’s top scientific breakthroughs of 2010).

penrose had previously championed the idea that the universe got its start well before the big bang, and has been cycling through an endless series of bangs for eons. as evidence for this strange claim, he and gurzadyan pointed out funny concentric circles in the universe’s baby photos, the cosmic microwave background. the cmb shows a universe that looks more or less the same in every direction, with a nearly uniform temperature of about 3 degrees kelvin.

[LightEye]

dear friends,

http://www.technologyreview.com/blog/arxiv/26763/

be well, be love.

david

milky way is warped, like a beer bottle cap

the discovery of a new arm in the milky way suggests that our galaxy is warped, say astronomers
kfc 05/16/2011

in 1852, stephen alexander, an astronomer at the college of new jersey, put forward the radical suggestion that the milky way galaxy is a spiral.

but while today's astronomers agree on this general shape, they disagree over the precise structure of the spiral and in particular on the number of arms.

astronomers have named at least 6 arms and in the 1990s, evidence emerged that the galaxy had a central bar. the uncertainty is easy to understand. our view of the galaxy shows the nearer stars superimposed on the ones that are further away. and much of the opposite side of the milky way galaxy is obscured entirely by the central mass of stars at the centre.

recently, however, a clearer picture has begun to emerge. the growing consensus is that the milky way has a central bar with two main arms, called the perseus arm, which passes with a few kiloparsecs of the sun, and the scutum-centaurus arm. (the other arms are now thought to be minor structures made up largely of gas.)

[Jeia Ra Manuk]

something big is going on at the center of the galaxy, and astronomers are happy to say they don’t know what it is.

http://www.nytimes.com/2010/11/10/sc...ml?ref=science


love
et

[weboy78]

http://www.physorg.com/news/2011-07-...ry-cosmos.html
physicists and astronomers have long believed that the universe has mirror symmetry, like a basketball. but recent findings from the university of michigan suggest that the shape of the big bang might be more complicated than previously thought, and that the early universe spun on an axis.

[weboy78]

http://www.newscientist.com/article/...-theories.html
sylos labini has made such a map using a subset of sloan data. it reveals clumpiness on unexpectedly large scales – though not as vast as these. he believes that the universe may have a fractal structure, looking similar at all scales.

[LightEye]

dear friends,

there you go the mobius ring... ;-)

http://www.dailymail.co.uk/sciencete...milky-way.html

be well, be love.

david

ribbon in the dust: the strange twisted ring of gas at the centre of the milky way
by daily mail reporter
last updated at 4:23 pm on 20th july 2011


a bizarre, twisted ring of dense gas at the centre of our milky way galaxy has been observed by the herschel space observatory.

only a few portions of the ring, which stretches across more than 600 light-years, were known before.

but herschel's view reveals the entire ring for the first time - and a strange kink that resembles a ribbon has astronomers scratching their heads.
new horizons: this bizarre, twisted ring of dense gas at the centre of our milky way galaxy was observed by the herschel space observatory

new horizons: this bizarre, twisted ring of dense gas at the centre of our milky way galaxy was observed by the herschel space observatory

nasa researcher alberto noriega-crespo, of the california institute of technology in pasadena, said: 'we have looked at this region at the centre of the milky way many times before in the infrared.

'but when we looked at the high-resolution images using herschel's sub-millimetre wavelengths, the presence of a ring is quite clear.'

the herschel space observatory is a european space agency-led mission with important nasa contributions.

it sees infrared and sub-millimetre light, which can readily penetrate through the dust hovering between the bustling centre of our galaxy and us. herschel's detectors are also suited to see the coldest stuff in our galaxy.


when astronomers turned the giant telescope to look at the centre of the milky way, it captured unprecedented views of its inner ring - a dense tube of cold gas mixed with dust, where new stars are forming.

astronomers were shocked by what they saw - the ring, which is in the plane of our galaxy, looked more like an infinity symbol with two lobes pointing to the side.

in fact, they later determined the ring was torqued in the middle, so it only appears to have two lobes. to picture the structure, imagine holding a stiff, elliptical band and twisting the ends in opposite directions, so that one side comes up a bit.

'this is what is so exciting about launching a new space telescope like herschel,' said lead researcher sergio molinari of the institute of space physics in rome, italy.

'we have a new and exciting mystery on our hands, right at the centre of our own galaxy.'

[LightEye]

dear friends,

http://www.scientificamerican.com/ar...allel-universe

be well, be love.

david

the case for parallel universes

why the multiverse, crazy as it sounds, is a solid scientific idea
by alexander vilenkin and max tegmark | july 19, 2011
image: chad hagen

ditor's note: in the august issue of scientific american, cosmologist george ellis describes why he's skeptical about the concept of parallel universes. here, multiverse proponents alexander vilenkin and max tegmark offer counterpoints, explaining why the multiverse would account for so many features of our universe—and how it might be tested.

welcome to the multiverse
by alexander vilenkin

the universe as we know it originated in a great explosion that we call the big bang. for nearly a century cosmologists have been studying the aftermath of this explosion: how the universe expanded and cooled down, and how galaxies were gradually pulled together by gravity. the nature of the bang itself has come into focus only relatively recently. it is the subject of the theory of inflation, which was developed in the early 1980s by alan guth, andrei linde and others, and has led to a radically new global view of the universe.

inflation is a period of super-fast, accelerated expansion in early cosmic history. it is so fast that in a fraction of a second a tiny subatomic speck of space is blown to dimensions much greater than the entire currently observable region. at the end of inflation, the energy that drove the expansion ignites a hot fireball of particles and radiation. this is what we call the big bang.

the end of inflation is triggered by quantum, probabilistic processes and does not occur everywhere at once. in our cosmic neighborhood, inflation ended 13.7 billion years ago, but it still continues in remote parts of the universe, and other “normal” regions like ours are constantly being formed. the new regions appear as tiny, microscopic bubbles and immediately start to grow. the bubbles keep growing without bound; in the meantime they are driven apart by the inflationary expansion, making room for more bubbles to form. this never-ending process is called eternal inflation. we live in one of the bubbles and can observe only a small part of it. no matter how fast we travel, we cannot catch up with the expanding boundaries of our bubble, so for all practical purposes we live in a self-contained bubble universe.

the theory of inflation explained some otherwise mysterious features of the big bang, which simply had to be postulated before. it also made a number of testable predictions, which were then spectacularly confirmed by observations. by now inflation has become the leading cosmological paradigm.

another key aspect of the new worldview derives from string theory, which is at present our best candidate for the fundamental theory of nature. string theory admits an immense number of solutions describing bubble universes with diverse physical properties. the quantities we call constants of nature, such as the masses of elementary particles, newton’s gravitational constant, and so on, take different values in different bubble types. now combine this with the theory of inflation. each bubble type has a certain probability to form in the inflating space. so inevitably, an unlimited number of bubbles of all possible types will be formed in the course of eternal inflation