An artist's impression of a neutron star. The cosmic object's 'nuclear pasta' would be located between the crust and the outer core of the neutron star. Credit: NASA/Dana Berry

The crusts of neutron stars — cosmic cousins of black holes — possess a weird form of matter known as "nuclear pasta."

Now, scientists have found that nuclear pasta may be even stranger than previously thought, forming defects that bond pieces together into complex, disorderly shapes. This complex nuclear pasta could ultimately doom the powerful magnetic fields seen from neutron stars, researchers say.

A neutron star, like a black hole, is a remnant of a star that died in a catastrophic explosion known as a supernova. Neutron stars are typically small, with diameters of about 12 miles (19 kilometers) or so, but they are so dense that a neutron star's massmay be about the same as that of the sun. A chunk of a neutron star the size of a sugar cube can weigh as much as 100 million tons, making neutron stars the densest objects in the universe besides black holes.

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The sun sets behind BICEP2, in the foreground, and the South Pole Telescope, in the background. (Steffen Richter/VagabondPix.com)

A new analysis has dynamited a much-hyped discovery of “gravitational waves” from the dawn of time. What had seemed to be a major breakthrough in cosmology, one that incited loose talk of Nobel prizes, now appears to have been a case of scientists over-interpreting their data.

Last March, in a highly anticipated news conference at Harvard, scientists with an experiment called BICEP2 revealed that their South Pole telescope had scanned the background radiation of the universe and made a dazzling discovery: The ancient light had apparently been polarized by gravitational waves emitted in the initial moment after the Big Bang, when the tiny, dense universe expanded violently.

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 A simulation of gravitational waves produced by two orbiting black holes. Photograph: Ligo Collaboration

Here’s a date for your diary: 1 January 2017. It’s the day that physicists are predicting for a great scientific breakthrough: the first direct detection of gravitational waves.

Even if you have not yet heard about gravitational waves, you are going to in the coming years. When they are detected, it will revolutionise our investigation of the universe.

It will be the equivalent of astronomers discovering a new sense. With telescopes, they can already see the universe. By detecting gravitational waves, they will be able to ‘listen’ to it as well. We would be able to ‘hear’ stars colliding with one another, the destruction of matter falling into black holes and the catastrophic detonation of distant massive stars.

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 Black holes create and destroy galaxies, like this spiral galaxy in the constellation Dorado. (Roberto Colombari/Stocktrek Images/Corbis)

Much has been made of the mind-bending visual effects in Interstellar. But the methods created by the film’s Oscar-nominated visual effects team may have more serious applications than wowing movie audiences—they could actually be useful to scientists, too. A new paper in Classical and Quantum Gravity tells how the Interstellar team turned science fiction towards the service of scientific fact and produced a whole new picture of what it might look like to orbit around a spinning black hole.

Director Christopher Nolan and executive producer (and theoretical physicist) Kip Thorne wanted to create a visual experience that was immersive and credible. When they began to construct images of a black hole within an accretion disk, they realized that existing visual effects technology wouldn’t cut it—it created a flickering effect that would have looked bad in IMAX theaters. So the team turned to physics to create something different.

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The twin 4-kilometer arms of LIGO Livingston embrace a working forest, where logging generates vibrations that the instrument must damp out.

After decades of effort, physicists say they are on the verge of detecting ripples in spacetime called gravitational waves, whose existence Albert Einstein himself predicted nearly a century ago. Researchers working on the Laser Interferometer Gravitational-Wave Observatory (LIGO) will use enormous instruments in Livingston, Louisiana, and Hanford, Washington, to look for the gravitational waves set off when two neutron stars spiral into each other. LIGO ran from 2002 to 2010 and saw nothing, but those Initial LIGO instruments aimed only to prove that the experiment was technologically feasible, physicists say. Now, they're finishing a $205 million rebuild of the detectors, known as Advanced LIGO, which should make them 10 times more sensitive and, they say, virtually ensure a detection. Such an observation would open up a whole new type of astronomy—and likely bag a Nobel Prize.

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Modern cosmology is dominated by two fundamental theories: general relativity, which describes the structure of space and time as manifold that interacts with mass/energy (aka gravity), and quantum theory, which describes the fundamental interactions of protons, electrons, light, etc. (aka quanta). Both models are strongly supported by experimental and observational evidence. The problem is that each theory makes fundamental assumptions about the way the universe works, and they contradict each other at a basic level. This isn’t a problem if you are interested in things on a large scale, such as planets and galaxies (general relativity), or things on a small scale such as nuclear fusion (quantum theory). The contradiction arises when you want to understand objects that are both very dense and interact at high energies, such as black hole interiors, the big bang, etc. So one of the challenges of modern cosmology is to develop a unified theory of quantum gravity, which would combine the predictions of general relativity and quantum theory in a consistent way.

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