Electron's shapeliness throws a curve at supersymmetry. A small band of particle-seeking scientists at Yale and Harvard has established a new benchmark for the electron's almost perfect roundness, raising doubts about certain theories that predict what lies beyond physics' reigning model of fundamental forces and particles, the Standard Model. "We know the Standard Model does not encompass everything," said Yale physicist David DeMille, who with John Doyle and Gerald Gabrielse of Harvard leads the ACME collaboration, a team using a strikingly different method to detect some of the same types of particles sought by huge experiments at the Large Hadron Collider (LHC) in Europe. "Like our LHC colleagues, we're trying to see something in the lab that's different from what the Standard Model predicts. " ACME is looking for new particles of matter by measuring their effects on the shape of the electron, the negatively charged subatomic particle orbiting within every atom.
Dark Matter ; the Undetectable Mass (FULL VIDEO) Is Dark Matter Made of Tiny Black Holes? A planet-hunting NASA spacecraft has detected no sign of moon-size black holes yet in the Milky Way galaxy, limiting the chances that such objects could make up most of the "dark matter" that has mystified scientists for decades. Dark matter is one of the greatest scientific mysteries known — an invisible substance thought to constitute up five-sixths of all matter in the universe.
It remains so mysterious that scientists are still uncertain as to whether dark matter is made of microscopic particles or far larger objects. The consensus right now is that dark matter consists of a new type of particle, one that interacts very weakly at best with all the known forces of the universe except gravity.
As such, dark matter is invisible and mostly intangible, with its presence only detectable via the gravitational pull it exerts. [Images: Black Holes of the Universe] But the new study finds no evidence to support this theory. Black Hole Quiz: How Well Do You Know Nature's Weir... More on black holes and quantum information. The article “Black holes, quantum information, and the foundations of physics,” by Steve Giddings ( Physics Today, April 2013, page 30), reviews the challenges that black holes present to the foundational principles of unitarity and causality in quantum theory.
The problems and paradoxes of black holes were inherent in the earliest discussions of the Hawking effect, and were brought to the attention of many physicists by Stephen Hawking himself. In reviewing the imaginative attempts, some of them quite radical, to reconcile black holes with quantum mechanics, Giddings ignores the simplest possibility of all: that because of quantum effects, a classical event horizon never forms. The widespread belief that gravitational collapse leads inevitably to an event horizon is based on an essentially classical view of the collapsing matter and its equation of state, a view that rests, in turn, upon the assumption that quantum effects are negligible on macroscopic scales.
Ask Ethan #6: The Center of the Universe. “If you look for truth, you may find comfort in the end; if you look for comfort you will not get either comfort or truth only soft soap and wishful thinking to begin, and in the end, despair.” -C. S. Lewis And yet, when you search for the truth, you often find answers that butt up against your sensibilities, your preconceptions, and even your very notions of common sense. Such is the case in this week’s Ask Ethan, where longtime reader and commenter MandoZink asks: I have a question that has perplexed me for most of my life. So let’s get to it: what’s the deal with the geometry of the Universe, and whether (or not) there’s a center?
Image credit: Tim Phelan of First off, it’s important to draw a distinction between what we know as “our Universe” — or what I’ll call the observable Universe — and “the Universe”, which includes everything that’s ever been connected to us since the Big Bang and a lot more. Image credit: NASA, ESA and A. Image credit: V. Physics won’t be the same again. Hunting quantum gravity in the big bang's echoes - space - 30 September 2013. Uniting gravity with its quantum nemesis might take a detector the size of the universe. So say two physicists who think they have found a way to resolve one of the biggest conflicts in modern physics using high-resolution maps of the infant cosmos.
The universe is currently described using two distinct frameworks: gravity for larger objects such as planets and black holes, and quantum mechanics for the tiny world of bosons and quarks. Even though almost everyone expects these realms to be linked, no one has been able to build a bridge between the two. Previous work focused on trying to finding the graviton – the quantum unit of gravity – the sheer existence of which would unite the two theories. "It's actually very hard to construct a consistent theory in which gravity is not quantised but the rest of the world is," says Steven Carlip at the University of California, Davis.
Force particles Quantum-mechanical activity Journal reference: arxiv.org/abs/1309.5343 More From New Scientist. Hunting quantum gravity in the big bang's echoes - space - 30 September 2013. Uniting gravity with its quantum nemesis might take a detector the size of the universe. So say two physicists who think they have found a way to resolve one of the biggest conflicts in modern physics using high-resolution maps of the infant cosmos.
The universe is currently described using two distinct frameworks: gravity for larger objects such as planets and black holes, and quantum mechanics for the tiny world of bosons and quarks. Even though almost everyone expects these realms to be linked, no one has been able to build a bridge between the two. Previous work focused on trying to finding the graviton – the quantum unit of gravity – the sheer existence of which would unite the two theories. "It's actually very hard to construct a consistent theory in which gravity is not quantised but the rest of the world is," says Steven Carlip at the University of California, Davis. Force particles Quantum-mechanical activity Journal reference: arxiv.org/abs/1309.5343 More From New Scientist.
A True Description of the Universe? – Page 3.14. Ethan wrote a very interesting post about parallel universes. That got me thinking, and thinking some more. In fact I’ve been thinking about this for nine years. So forgive me as it starts to make some sense to me, and read the following with a pinch of salt. Time is not the 4th dimension. Time, while a dimensional experience, is purely a product of consciousness. The physical universe incorporates both past and future; the universe, in essence, is a singularity.
Within a 10-dimensional orbit of the singularity is the potential for all matter and energy. In fact, every galaxy in the observable universe is as near the edge of the universe as we are (although they appear, through telescopes, where they were in aeons past). At the “beginning” of “time,” the universe is 10-dimensional. If there is a multiverse in the sense of quantum potential, it is possible that only living consciousness collapses it and makes it solid. Symmetry in the universe: Physics says you shouldn’t exist. Illustration by Alex Eben Meyer You’re almost unfathomably lucky to exist, in almost every conceivable way. Don’t take it the wrong way. You, me, and even the most calming manatee are nothing but impurities in an otherwise beautifully simple universe.
We're lucky life began on Earth at all, of course, and that something as complex as humans evolved. But even so, I have news for you: It's worse than you think. Your existence wasn’t just predicated on amorousness and luck of your ancestors, but on an almost absurdly finely tuned universe. Worse still, the laws of physics themselves seem to be working against us. My physicist colleagues and I like to pretend that the laws of physics are orderly and elegant. The history of physics, in fact, is a marvel of using simple symmetry principles to construct complicated laws of the universe.
The long-overlooked 20th-century mathematician Emmy Noether proved the centrality of symmetry as a physical principle. Everything is kinda the same? Very. Patricia Burchat: Shedding light on dark matter. Why we think there’s a Multiverse, not just our Universe. “Every true, eternal problem is an equally true, eternal fault; every answer an atonement, every realisation an improvement.” -Otto Weininger The best measurements of the distant Universe — out beyond our galaxy — have led us to the current picture of exactly what our Universe is doing: expanding and cooling, with its galaxies progressively getting farther and farther apart.
Image credit: Molly Read for the University of Wisconsin-Madison. But what does that mean for our past? If we’re expanding and cooling, that means our past was less expanded and less cooled, or as we like to think of it, denser and hotter. Now, if you’re thinking like a scientist, you don’t just want to know what it’s doing. And the answer is actually straightforward: if general relativity is your theory of gravity, the Universe’s expansion rate is determined by what type of energy dominates your Universe. Image credit: NASA, ESA, and J. And when you have a Universe dominated by matter, here’s how it expands. Are Parallel Universes Real? Farnsworth: “There is it. The edge of the Universe!”
Fry: “Far out. So there’s an infinite number of parallel Universes?” Farnsworth: “No, just the two.” Our existence here in this Universe is something that we know is rare, special, beautiful, and full of wonder. Image credit: Kelly Montgomery. Some things happen with amazing regularity and predictability: the occurrence of days-and-nights, the tides, the seasons, the motion of the heavenly bodies, and so much more. And yet, it’s not an entirely predictive system! But then quantum physics came along. Image credit: © Copyright CSIRO Australia 2004, via And it turns out that knowing the positions and momenta of particles — even of every particle in the Universe — isn’t enough to determine the properties of that particle in the future. Image credit: Robert Austin and Lyman Page / Princeton University.
Sure, if you fire enough photons, you can be confident in the pattern that will emerge, statistically. The Strangest Black Holes in the Universe. Credit: Alain R. | Wikimedia CommonsBlack holes are gigantic cosmic monsters, exotic objects whose gravity is so strong that not even light can escape their clutches. Black holes come in a wide variety of forms, from small stellar-mass bodies to the supermassive beasts that reside at the hearts of galaxies. Here are 10 of the most extreme black holes, from the smallest to the largest and from cannibals to rogues. FIRST UP: The biggest and baddest. Novikov self-consistency principle. The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity (solutions containing what are known as closed timelike curves).
The principle asserts that if an event exists that would give rise to a paradox, or to any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes. History of the principle[edit] Physicists have long been aware that there are solutions to the theory of general relativity which contain closed timelike curves, or CTCs—see for example the Gödel metric.
Novikov discussed the possibility of CTCs in books written in 1975 and 1983, offering the opinion that only self-consistent trips back in time would be permitted. Time loop logic[edit] What does the Universe look like as seen from its most distant galaxy? “One sees qualities at a distance and defects at close range.” -Victor Hugo A couple of weeks ago we took a look at the most distant galaxy (so far) in the known Universe, a galaxy so far away that it takes exclusively infrared observations from our most power space telescopes (Hubble and Spitzer) in order to detect it. What’s perhaps even more remarkable is that the light we do detect from it — the light we detected in the infrared — was actually emitted in the Ultraviolet part of the spectrum!
Image credit: NASA, ESA, Garth Illingworth (University of California, Santa Cruz) and Rychard Bouwens (University of California, Santa Cruz and Leiden University) and the HUDF09 Team. It’s only the vast expansion-and-redshift of the Universe that has taken place, along with the fact that the light has been traveling for some 13.4 billion years, that allow us to observe it as we do. Image credit: Dave Morrow, ©2013 OneBigPhoto.com.
Image credit: Richard Powell of. Goodbye Big Bang, Hello Black Hole? A New Theory Of The Universe’s Creation. Want to stay on top of all the space news? Follow @universetoday on Twitter Artist’s conception of the event horizon of a black hole. Credit: Victor de Schwanberg/Science Photo Library Could the famed “Big Bang” theory need a revision? Before getting into their findings, let’s just preface this by saying nobody knows anything for sure. “For all physicists know, dragons could have come flying out of the singularity,” stated Niayesh Afshordi, an astrophysicist with the Perimeter Institute for Theoretical Physics in Canada who co-authored the new study. So what are the limitations of the Big Bang theory?
Most cosmologists say the universe must have been expanding faster than the speed of light for this to happen, but Ashford says even that theory has problems: “The Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on.” This is what the physicists propose: The long and the short of it? Source: Nature About Elizabeth Howell. Is it time to rewrite the laws of physics? 'Time is an illusion. Lunchtime doubly so,” said Ford Prefect in Douglas Adams’s The Hitchhiker’s Guide to the Galaxy. For the past century, mainstream physics has agreed with him. To most of us, it seems obvious that the world is moving steadily forward through time, from a known past, through an active present, into a mysterious future. But, as Einstein said, “physicists believe the separation between past, present, and future is only an illusion, although a convincing one”.
“Mainstream physics basically eliminates time as a fundamental aspect of nature,” explains Prof Lee Smolin, a physicist at the Perimeter Institute for Theoretical Physics, in Ontario, Canada. Under this system, what is actually real is not our passage through time, but the whole of reality at once. He thinks that it is high time – so to speak – this view was overturned. The question of what time is, and whether it is real or illusory, is an ancient one. Sir Isaac Newton, a thousand years later, disagreed.
Theoretical physics: The origins of space and time.