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Dark matter caused the demise of the dinosaurs? by John G. Hartnett Published: 13 December 2016 (GMT+10) Harvard University LisaRandallHarvardEdu American theoretical physicist and cosmologist Dr Lisa Randall is another scientist grasping at dark matter for answers. Dark matter has been invoked to solve many vexing problems in astrophysics and cosmology.1 Now it seems it has been invoked to solve the evolutionists’ problem of extinction of the dinosaurs.2 American theoretical physicist and cosmologist Dr Lisa Randall has developed a breakthrough five dimensional warped geometry theory. About two years ago she proposed a new hypothesis on dark matter which suggests the...

On this, the day after the election of Donald J. Trump as the 45th president (yes, he has already updated his Twitter profile), President Barack Obama’s 2016 Federal Register page count stands at a record-level 78,898.The Federal Register, so emblematic of Washington excess, is where the hundreds of Washington bureaucracies post their proposed and final rules and regulations each day.Obama will break his own all-time record of 81,405 pages even before December gets here. Of the ten highest-ever Federal Register page counts, the incumbent president will own seven of them.Within those pages, several thousand rules get issued annually, no matter...

Scientists are ecstatic over the fact that they may have just discovered the fifth fundamental force of nature. The possible discovery of a previously-unknown subatomic particle looks set to finally bring the elusive dark matter into the mix. The discovery centers on a new type of boson that possesses characteristics previously unseen in particles. Furthermore, its existence casts doubt upon whether the known ‘sector’ of matter and particles exists alongside a ‘dark’ sector – both interacting with each other via another, unseen force.“If true, it's revolutionary,” said Jonathan Feng, professor of physics & astronomy at the University of California, Irvine,...

How do you build a real-world machine to test the most abstract of theories? Janna Levin talks with Rai Weiss, one of the original designers of LIGO, the four-kilometer-long instrument that has now twice detected the distant reverberations of two black holes crashing into one another. Janna Levin is a theoretical physicist — she works with pen and paper to turn the elegant rules of the universe into theory. Rainer Weiss, or Rai, as he’s known, is an experimental physicist — he thinks about how to find and measure something that may or may not exist outside of theory. Weiss...

The idea that our Universe is filled with dark matter has been around for nearly a century. When astronomers noticed that orbital speeds towards the edges of spiral galaxies remain the same or even increase slightly, rather than decrease, they surmised that either there must be some huge unseen mass driving the rotation, or that the laws of gravity given by Einstein's General Relativity need to be changed. They elected the first option. Over that time, cosmologists have accumulated boatloads of evidence in favor of the notion that this invisible, "dark" matter -- which neither interacts with nor emits light...

Explanation: Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of...

Bursts of gamma rays from the center of our galaxy are not likely to be signals of dark matter but rather other astrophysical phenomena such as fast-rotating stars called millisecond pulsars, according to two new studies, one from a team based at Princeton University and the Massachusetts Institute of Technology and another based in the Netherlands. Previous studies suggested that gamma rays coming from the dense region of space in the inner Milky Way galaxy could be caused when invisible dark matter particles collide. But using new statistical analysis methods, the two research teams independently found that the gamma ray...

Black holes can only grow if they have a gas disc to feed on NASA Goddard Space Flight Center/Flickr ======================================================================================================== Black holes can only grow to 50 billion times the mass of the Sun, before they lose their only source of 'food' and stop growing. Scientists discovered that black holes have a size limit, as when it gets so big, the gas which feeds the great void loses its energy, and falls into the unknown. A researcher from the University of Leicester analysed the disc of gas which surrounds supermassive black holes at the centre of galaxies. He found that...

In what amounts to stunning acknowledgement of its very existence, and a reversal of existing policy, Congress yesterday passed legislation by a wide margin granting sweeping federal regulatory authority over dark matter. Obama has already promised to sign the legislation which he termed “a small step in the right direction.” The vote culminated months of secret negotiations and political horse-trading. Up till now, each state has been free to regulate dark matter in its own way and of its choosing. The law now prohibits independent state action on dark matter, making it the exclusive province of the federal government. Tenth...

TORONTO — Dark matter inspires many strange theories, but until now few have involved giant lizards and the origins of humanity. If physicist Lisa Randall’s theory is correct, however, there is a clear link between dark matter, the great unknown majority of universal stuff and the extinction of the dinosaurs, which cleared the path for the rise of mammals, including that special species, homo sapiens. Roughly, her idea is that the rotation of a vast disc of dark matter through our solar system dislodged an asteroid from a weak and distant orbit, and sent it hurtling toward Earth, where it...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 September 17 A Force from Empty Space: The Casimir Effect Credit & Copyright: Umar Mohideen (U. California at Riverside) Explanation: This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for...

Explanation: This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for its discoverer, who, 55 years ago, was trying to understand why fluids like mayonnaise move so slowly. Today, evidence indicates that most of the energy density in the universe is in an unknown form dubbed dark energy. The form and genesis of dark energy is almost completely unknown, but postulated as related...

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...