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Submission + - Existence of cosmic neutrino background confirmed->

StartsWithABang writes: The hot Big Bang — proposed seventy years ago — is a tremendous success story. Predicated on the assumption that the Universe was hotter, denser, more uniform and expanding faster in the past, it’s allowed us to predict the rate of cosmic expansion over distance and time, the primeval abundances of the light elements, the formation and evolution of large-scale-structure, and the existence and properties of the cosmic microwave background: the leftover photon glow from the Big Bang. All these predictions have been borne out, but there’s one more prediction that has yet to be tested: the existence and properties of a cosmic neutrino background. A just detected the cosmic neutrino background definitively and in a new way, with the subsequent polarization spectra — set to be released by the Planck team — ready to confirm the greatest prediction of all: the cosmic neutrino background’s temperature!
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Submission + - How do we know the Universe's fabric is expanding?

StartsWithABang writes: When it comes to the Universe, physicists say things like: it originated in a Big Bang, it's isotropic (or the same in all directions), and it's homogeneous (the same everywhere), save for the effects of cosmic evolution. In every direction we look, we see galaxies expanding away from us, with the expansion rate increasing the farther away we look. But an expansion inherent to the fabric of space itself isn't the only explanation; it's conceivable that we see what we see because everything else in the Universe is speeding away from us, and that spacetime itself is static. Here's what the Universe itself has to say about those two possibilities.

Submission + - Mystery of why Saturn gets planet-encircling storms every 20 years solved

StartsWithABang writes: Every twenty years or so, Saturn develops a tremendous storm, streaking white across its surface and eventually encircling the entire globe, lapping itself. The 2010-2011 storm outdid itself, lasting more than eight months and becoming the largest storm since telescope technology advanced to the point where we could view them. Four years after it ended, we finally figured out the secret to what causes them, and why they only emerge every 20-to-30 years.

Submission + - Hubble catches a star cluster lying about its age

StartsWithABang writes: When you look at a globular cluster, you’re seeing a relic from the ancient Universe, where its stars formed back when the Universe was just a few percent of its present age. At least, that’s what you see in general, but a few globulars are much, much younger than that. Hubble has recently photographed a cosmic impostor, NGC 1783, which is only 10% the age of most globulars. Here's the secret of how it got to be that way, and how to catch lying globulars in general.

Submission + - How close are we, really, to nuclear fusion?

StartsWithABang writes: The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion. The same process that powers the core of the Sun could also power everything on Earth millions of times over, if only we could figure out how to reach that breakeven point. Right now, we have three different candidates for doing so: inertial confinement, magnetic confinement, and magnetized target fusion. Recent advances have all three looking promising in various ways, making one wonder why we don't spend more resources towards achieving the holy grail of energy.

Submission + - Stephen Hawking's proposal to solve the information paradox is no solution

StartsWithABang writes: Stephen Hawking is claiming that the black hole information paradox has now been resolved, with the information encoded on the event horizon and then onto the outgoing radiation via a new mechanism that he’ll detail in a paper due out next month, along with collaborators Malcom Perry and Andrew Strominger. Only, that’s not really what’s happening here. While he does have a new idea and there is a paper coming out, its contents do not solve the information paradox, but merely provide a hypothesis as to how it may be solved in the future.

Submission + - Do you really love science enough to recognize hype in headlines?

StartsWithABang writes: When you first venture out into the world, you're armed, as a human being, with an incredible intelligence, but with no experience. All sorts of basic things must be learned, often the hard way: hot things will burn you, hot things that don't look hot will also burn you, and that even very cold things will burn you, too. Figuring those things out — and the process by which you learn them — is science, in and of itself. But to move forward requires that we understand why, and that's where scientific theories, leaps and even revolutions come into play.

Submission + - Has Stephen Hawking solved the black hole information paradox?

StartsWithABang writes: Earlier this week, Stephen Hawking shook up the world when he announced that he had uncovered the solution to the black hole information paradox at a conference in Stockholm. When particles fall into (or create) a black hole, information is encoded on the black hole’s surface, but when the black hole decays into radiation, that information appears to be lost, as the radiation is thermal. But perhaps the information is stored on the event horizon, and can be encoded into the outgoing radiation thanks to the interplay of gravitation and matter. Details should be forthcoming in a paper to be released next month by Hawking, Malcom Perry and Andrew Strominger.

Submission + - How fast we're moving relative to the Universe known for certain

StartsWithABang writes: If you wanted to know how fast you were moving through space, you’d need to measure it all: the Earth’s rotation, our motion around the Sun, the Sun’s motion through the galaxy, the Milky Way’s speed within the local group, and finally how the local group moved relative to the Universe. All in all, it’s a daunting, virtually impossible task without literally measuring everything in the entire Universe itself. Or, you could take advantage of an amazing fact: the leftover glow from the Big Bang exhibits a redshift in one direction and a blueshift in the other. In other words, the cosmic microwave background has a dipole, and that dipole tells us our motion relative to the Universe!

Submission + - Some observers perceive the Universe to be much younger than we do

StartsWithABang writes: It’s been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we’re seeing it as it was in the past. Its age — as it appears — is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old. But it is actually possible for an observer living on another planet, star or galaxy to perceive that significantly less time has passed since the Big Bang, so long as they were moving close to the speed of light relative to the CMB. Paradoxically, if they slowed their speed, they’d find that they themselves were very young, but living in a 13.8 billion year-old Universe.

Submission + - It takes 26 fundamental constants to describe our Universe

StartsWithABang writes: The standard model, gravity, and all the known particles and interactions can be semi-elegantly explained with only 26 parameters, including dark energy and neutrino masses. And yet with these 26 constants, we still don’t get everything: dark matter, the matter-antimatter asymmetry and cosmic inflation may yet dictate that more parameters are required to give us everything our Universe requires. Is there a more fundamental theory out there to describe it all more simply? Or is this simply a messy, inelegant Universe we’re stuck with?

Submission + - It may be impossible to know the origin of our Universe

StartsWithABang writes: If we trace the evolution of our Universe back in time, we can arrive at a time before there were organic molecules, rocky planets, heavy elements, galaxies, stars, or even neutral atoms. The farther back we go, the hotter the Universe gets, the higher in density and temperature, and more uniform. But at some point, this hot, dense, expanding state ceases to describe our Universe. Because preceding it was a period of cosmic inflation: a period of indeterminate duration. It must have lasted at least some 10^-35 seconds, but it could have lasted much, much longer, including the possibility that it was around for an infinite amount of time. But we may never know, because the nature of inflation wipes that information out from our Universe altogether.

Submission + - The most impossible idea from Star Trek is the transporter

StartsWithABang writes: Today would have been the 95th birthday of Gene Roddenberry, the mind that brought us the Universe of Star Trek. In addition to a utopia where maladies like hunger, disease and poverty were eradicated, Star Trek promised a future where technology was widely available and sufficiently advanced to the benefit of all of humanity. While many of these imagined advances in technology have been met or even exceeded already, such as in the field of medical diagnostics and communication, others like warp drive and the Star Trek transporter may never come to fruition. No matter how much your technology advances, you still can’t circumvent the laws of nature.

Submission + - Gravity doesn't always add up

StartsWithABang writes: Every time you follow the motion of a spacecraft, moon, planet or other object through the Solar System, you’re putting the theory of gravity to the test. On one hand, there’s a robust set of predictions for what the behavioral motion of these bodies ought to be, while on the other there’s what we actually observe. Sometimes, a mismatch indicates the need for something new, like a new planet or a new law of gravity. But other times, there are mundane explanations that account for these “apparent” discrepancies, such as radioactive decay, heating from the Sun or the fact that the Earth rotates on its axis. Not all the phenomena of our Solar System have been explained, however, including the flyby anomalies and the changing perigee/apogee difference of the Moon, with compelling indications that new physics may be right around the corner.

Submission + - The Death Star could become a reality with asteroid-sized antimatter chunks

StartsWithABang writes: The ability to destroy an Alderaan-like (or, ahem, Earth-like) planet has long been the dream of slashdotters everywhere. But generating the power necessary to unbind a planet — some 2.24 x 10^32 Joules — is simply impossible on board an object only the size of a small moon. But if, instead, you could house a 1-2 trillion ton asteroid (about 5-7 km across) made of antimatter and deliver it to the planet's core, Einstein's E=mc^2 ensures that the planet will be destroyed in seconds. And now, you will witness the power of this fully armed and operational battle station!

As long as we're going to reinvent the wheel again, we might as well try making it round this time. - Mike Dennison

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