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Gary Prezeau of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., describes the results of his theoretical model that goes some way to explain how streams of dark matter particles may interact with our planet's gravitational field. "A (dark matter) stream can be much larger than the solar system itself, and there are many different streams crisscrossing our galactic neighborhood," said Prézeau in a JPL press release. "When gravity interacts with the cold dark matter gas during galaxy formation, all particles within a stream continue traveling at the same velocity." As these streams begin to interact with a planet, according to...

Where do we come from? There are many right answers to this question, and the one you get depends on who you ask. For example, an astrophysicist might say that the chemical components of our bodies were first forged in the nuclear fires of stars. On the other hand, an evolutionary biologist might look at the similarities between our DNA and that of other primates' and conclude we evolved from apes. Lisa Randall, a theoretical physicist at Harvard University, has a different, and novel answer, which she describes in her latest book, "Dark Matter and the Dinosaurs." Randall has written...

CalTech astronomer Fritz Zwicky was the first to conceive of dark matter, supernovas and neutron stars. He also had a theory about colonizing the solar system using nuclear bombs. We could terraform other planets, he argued, by pulverizing them and then moving them closer or further from the sun. ...

White Hole. Credit: universe-review.ca =================================================================================================================== Black holes are created when stars die catastrophically in a supernova. So what in the universe is a white hole? It's imagination day, and we're going to talk about fantasy creatures. Like unicorns, but even rarer. Like leprechauns, but even more fantastical! Today, we're going to talk about white holes. Before we talk about white holes, let's talk about black holes. And before we talk about Black Holes, what's is this thing you have with holes exactly? Black holes are places in the universe where matter and energy are compacted so densely together that their...

Sometimes you have to think outside the box. Faced with some of the universe’s most stubborn mysteries, such as the identity of dark matter, physicists are turning to a technique that employs the weird laws of quantum mechanics: atom interferometry. Atom interferometers allow the study of various physical phenomena by splitting atom waves using a nanograting, such as this one. Composed of silicon nitride, this grating, imaged with a scanning electron microscope, has a period of 100 nm. Image courtesy of Alex Cronin (University of Arizona, Tucson, AZ). This method, which takes advantage of the fact that quantum particles behave...

Could the famed “Big Bang” theory need a revision? A group of theoretical physicists suppose the birth of the universe could have happened after a four-dimensional star collapsed into a black hole and ejected debris. Before getting into their findings, let’s just preface this by saying nobody knows anything for sure. Humans obviously weren’t around at the time the universe began. The standard theory is that the universe grew from an infinitely dense point or singularity, but who knows what was there before? “For all physicists know, dragons could have come flying out of the singularity,” stated Niayesh Afshordi, an...

The Case for Complex Dark Matter The physicist James Bullock explains how a complicated “dark sector” of interacting particles may illuminate some puzzling observations of the centers of galaxies. Jonathan Alcorn for Quanta MagazineJames Bullock, a physicist at the University of California, Irvine, imagines what the universe would look like if dark matter interacted with itself. By: Liz KruesiAugust 20, 2015 Dark matter — the unseen 80 percent of the universe’s mass — doesn’t emit, absorb or reflect light. Astronomers know it exists only because it interacts with our slice of the ordinary universe through gravity. Hence the hunt for this...

In the center of most galaxies (ours included) there is a supermassive black hole that holds everything together. However, one galaxy 10.5 billion light years away looks like it might have two black holes, and just like in Highlander, there can be only one. Scientists believe the pair are going to crash into each other in just 21 years. This could provide an unprecedented opportunity to observe the mind-boggling physics of such an event. The galaxy in question doesn’t have a snazzy name — it’s known only as PSO J334.2028+01.4075. It’s what is known as a quasar, or an “active...

The research and maps, which span a large area of the sky, are the product of a massive effort of an international team from the US, UK, Spain, Germany, Switzerland, and Brazil. They announced their new results at the American Physical Society (APS) meeting in Baltimore, Maryland. According to cosmologists, dark matter particles stream and clump together over time in particular regions of the cosmos, often in the same places where galaxies form and cluster. Over time, a “cosmic web” develops across the universe. Though dark matter is invisible, it expands with the universe and feels the pull of gravity....

A new out-of-this-world theory links mass extinctions with exotic astrophysics and galactic architecture Every once in a great while, something almost unspeakable happens to Earth. Some terrible force reaches out and tears the tree of life limb from limb. In a geological instant, countless creatures perish and entire lineages simply cease to exist. The most famous of these mass extinctions happened about 66 million years ago, when the dinosaurs died out in the planet-wide environmental disruption that followed a mountain-sized space rock walloping Earth. We can still see the scar from the impact today as a nearly 200-kilometer-wide crater in...

A new study published Thursday in Science suggests that dark matter might be able to zip through the universe without slowing or dragging because particles of it don't even interact with each other. Based on what we can observe about the universe, galaxies should be tearing themselves apart. That's where so-called dark matter comes in: It's a term for the as-of-yet unobserved matter that must be bulking up cosmos, giving galaxies the gravity they need to spin at the rates they do without falling to pieces. But even though we haven't caught dark matter (so named because it doesn't interact...

Now, you might be saying, if we don’t know what this thing is, and we can’t detect it. How do we know it’s actually there? Isn’t it probably not there, like dragons? How do we know dark matter actually exists, when we have no idea what it actually is? Oh, it’s there. In fact, pretty much all we know is that it does exist. Dark matter was first theorized back in the 1930s by Fritz Zwicky to account for the movement of galaxy clusters, but the modern calculations were made by Vera Rubin in the 1960s and 70s. She calculated...

Dark matter has long remained one of the greatest unsolved mysteries of the universe. While its presence can be inferred from the gravitational pull it exerts on visible matter, the fact that it does not emit or absorb any radiation makes it next to impossible to detect. ... The new model put forward by a team headed by Christoffer Petersson, a theoretical particle physicist from Chalmers University of Technology in Sweden, suggests that the Higgs boson, discovered by the LHC in 2012, might be responsible for the birth of dark matter particles. According to this model, if supersymmetry is real,...

Scientists name new ‘object’ SDSS J0100+2802 and say it is 12.8bn light years from Earth and was formed just 900m years after the Big Bang *************************************************************A monster black hole powering “the brightest lighthouse in the distant universe” has been discovered that is 12bn times more massive than the sun, scientists have revealed.The extraordinary object is at the centre of a quasar - an intensely powerful galactic radiation source - with a million billion times the sun’s energy output.For years the nature of quasars, discovered in 1963, remained a mystery. Today scientists believe they are generated by matter heating up as...

Astronomers have discovered the largest and most luminous black hole ever seen — an ancient monster with a mass about 12 billion times that of the sun — that dates back to when the universe was less than 1 billion years old. It remains a mystery how black holes could have grown so huge in such a relatively brief time after the dawn of the universe, researchers say.

Is it a message from far beyond out own galaxy? A brief mysterious pulse detected by Arecibo telescope has baffled boffins. The discovery of a split-second burst of radio waves by scientists using the Arecibo radio telescope in Puerto Rico raises major new questions over what caused it. The finding by an international team of astronomers, published July 10 in The Astrophysical Journal, marks the first time that a so-called 'fast radio burst' has been detected using an instrument other than the Parkes radio telescope in Australia.

~snip~ In 1967 British astronomer Jocelyn Bell Burnell was left stunned by mysterious pulsing signals she detected coming from outside the solar system. For months she suggested the signals could be of an extraterrestrial intelligent origin, but they were later proven to be rapidly spinning stars known as pulsars. However, a new series of mysterious signals, known as Fast Radio Bursts (FRBs), has again got astronomers scratching their heads and wondering if, maybe, we’re picking up alien messages...

Based on the latest evidence and theories our galaxy could be a huge wormhole (or space-time tunnel, have you seen the movie "Interstellar?") and, if that were true, it would be "stable and navigable." This is the hypothesis put forward in a study published in Annals of Physics and conducted with the participation of SISSA in Trieste. The paper, the result of a collaboration between Indian, Italian and North American researchers, prompts scientists to re-think dark matter. "If we combine the map of the dark matter in the Milky Way with the most recent Big Bang model to explain the...

The test rig for the Dark Energy Camera (DECam) at Fermilab. I picked this image today because it kinda sorta looks like the wormhole-making machine from the film version of Contact. [Credit: moi]A lot of science fiction plot devices are devoted to getting around the speed of light. In the real Universe, nothing with mass can travel faster than light, which means we can’t travel to distant stars without taking decades, centuries, or longer in transit. So, sci-fi draws from teleportation, hyperdrive, warp drive, and the ultimate cosmic short-cut: wormholes.[1] In some cases, the source of a science fiction...

Some simple observations about the universe seem to contradict basic physics. Solving these paradoxes could change the way we think about the cosmos Revolutions in science often come from the study of seemingly unresolvable paradoxes. An intense focus on these paradoxes, and their eventual resolution, is a process that has leads to many important breakthroughs. So an interesting exercise is to list the paradoxes associated with current ideas in science. It’s just possible that these paradoxes will lead to the next generation of ideas about the universe. Today, Yurij Baryshev at St Petersburg State University in Russia does just this...