Van der Waals interactions between molecules are among the most important forces in biology, physics, and chemistry, as they determine the properties and physical behavior of many materials. For a long time, it was considered that these interactions between molecules are always attractive. Now, researchers have found that in many rather common situations in nature the van der Waals force between two molecules becomes repulsive.
Researchers have simulated the formation of our entire Universe with a large supercomputer. A gigantic catalogue of about 25 billion virtual galaxies has been generated from 2 trillion digital particles. This catalogue is being used to calibrate the experiments on board the Euclid satellite, that will be launched in 2020 with the objective of investigating the nature of dark matter and dark energy.
Neutron scattering has revealed in unprecedented detail new insights into the exotic magnetic behavior of a material that could pave the way for quantum calculations far beyond the limits of a computer's binary code. A research team has confirmed magnetic signatures likely related to Majorana fermions--elusive particles that could be the basis for a quantum bit, or qubit, in a two-dimensional graphene-like material, alpha-ruthenium trichloride.
Scientists reviewed three experiments that hint at a phenomenon beyond the Standard Model of particle physics, outlines a new report.
In the first moments after the Big Bang, the Universe was able to expand even billions of billions of billions of times faster than today. Such rapid expansion should be due to a primordial force field, acting with a new particle: inflaton. From the latest analysis of the decay of mesons, carried out in the LHCb experiment by physicists from Cracow and Zurich, it appears, however, that the most probable light inflaton almost certainly does not exist.
Albert Einstein predicted that whenever light from a distant star passes by a closer object, gravity acts as a kind of magnifying lens, brightening and bending distant starlight. Yet, Einstein added, 'There is no hope of observing this phenomenon directly.' Now, researchers have done just that, saying that the discovery opens a new window to understanding 'the history and evolution of galaxies such as our own.'
Mountain lions in the Santa Ana mountains have lowest genetic diversity ever reported for pumas besides the Florida panther. Of seven male pumas that crossed 1-15 in past 20 years, only one produced offspring, report researchers.
Engineers tested several advanced sensors that can collectively measure strain, temperature, movement and leakage – installed along a 40-foot section of a hazard-resilient pipeline being tested for earthquake fault-rupture performance. The results could have huge consequences for urban planners and municipal leaders.
Nanometric-sized water drops are everywhere - in the air as droplets or aerosols, in our bodies as medication, and in the earth, within rocks and oil fields. To understand the behavior of these drops, it is necessary to know how they interact with their hydrophobic environment. This interaction takes places at the curved droplet interface, a sub-nanometric region that surrounds the small pocket of water.
The study, published in the New Journal of Physics, shows that physicists pay less attention to theories that are crammed with mathematical details. This suggests there are real and widespread barriers to communicating mathematical work, and that this is not because of poor training in mathematical skills, or because there is a social stigma about doing well in mathematics.
New research has confirmed a decades-old theory describing the dynamics of continuous phase transitions. The findings provide the first clear demonstration of the Kibble-Zurek mechanism for a quantum phase transition in both space and time. Physicists observed the transition in gaseous cesium atoms at temperatures near absolute zero.
Researchers have demonstrated the existence of a tetraneutron, a subatomic structure once thought unlikely to exist.
Researchers report a new method to use lasers as optical "tweezers" to pick individual atoms out from a cloud and hold them in place. As the atoms are "trapped," the scientists use a camera to create images of the atoms and their locations. Based on these images, they then manipulate the angle of the laser beams, to move individual atoms into any number of different configurations.
An international team of physicists has developed a pioneering approach to using Ultrahigh Energy Cosmic Rays (UHECRs)—the highest energy particles in nature since the Big Bang—to study particle interactions far beyond the reach of human-made accelerators.
How do you handle nuclear waste that will be radioactive for millions of years, keeping it from harming people and the environment? It isn’t easy, but a researcher has discovered ways to immobilize such waste – the offshoot of decades of nuclear weapons production – in glass and ceramics
In 1937, US physicist Isidor Rabi introduced a simple model to describe how atoms emit and absorb particles of light. Until now, this model had still not been completely explained. In a recent article, physicists have for the first time used an exact numerical technique: the quantum Monte Carlo technique, which was designed to explain the photon absorption and emission phenomenon.
Researchers propose an approach to the experimental data generated by the Large Hadron Collider that solves the infinity problem without breaching the four dimensions of space-time.
A simple question from his wife -- Does physics really allow people to travel back in time? -- propelled a physicist on a quest to resolve a fundamental problem that had puzzled him throughout his 45-year career: Why does the arrow of time flow inexorably toward the future, constantly creating new "nows"?
Researchers have found a significant new relationship in spiral and irregular galaxies: the acceleration observed in rotation curves tightly correlates with the gravitational acceleration expected from the visible mass only. The discovery may alter the understanding of dark matter and the internal dynamics of galaxies.
The universe is expanding uniformly. Space isn't stretching in a preferred direction or spinning.
If you bottle up a gas and try to image its atoms using today's most powerful microscopes, you will see little more than a shadowy blur. Atoms zip around at lightning speeds and are difficult to pin down at ambient temperatures. If, however, these atoms are plunged to ultracold temperatures, they slow to a crawl, and scientists can start to study how they can form exotic states of matter, such as superfluids, superconductors, and quantum magnets.
A black hole destroying a star, an event astronomers call 'stellar tidal disruption,' releases an enormous amount of energy, brightening the surroundings in an event called a flare. Two new studies characterize tidal disruption flares by studying how surrounding dust absorbs and re-emits their light, like echoes. This approach allowed scientists to measure the energy of flares from stellar tidal disruption events more precisely than ever before.
Dwarf galaxies are enigmas wrapped in riddles. Although they are the smallest galaxies, they represent some of the biggest mysteries about our universe. While many dwarf galaxies surround our own Milky Way, there seem to be far too few of them compared with standard cosmological models, which raises a lot of questions about the nature of dark matter and its role in galaxy formation. New theoretical modeling work offers the most accurate predictions to date about the dwarf galaxies in the Milky Way's neighborhood.
Using colors to identify the approximate ages of more than 130,000 stars in the Milky Way's halo, astronomers have produced the clearest picture yet of how the galaxy formed more than 13.5 billion years ago.
Trying to understand a system of atoms is like herding gnats -- the individual atoms are never at rest and are constantly moving and interacting. When it comes to trying to model the properties and behavior of these kinds of systems, scientists use two fundamentally different pictures of reality, one of which is called 'statistical' and the other 'dynamical.'
The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers, only occasionally slurping small sips of hydrogen gas. But it wasn't always this way. A new study shows that 6 million years ago, when the first human ancestors known as hominins walked the Earth, our galaxy's core blazed forth furiously. The evidence for this active phase came from a search for the galaxy's missing mass.
An international team of researchers has discovered that in a very high magnetic field an electron with no mass can acquire a mass. Understanding why elementary particles have a mass is a fundamental question in physics and an area of intense debate.
ESA's Planck satellite has revealed that the first stars in the Universe started forming later than previous observations of the Cosmic Microwave Background indicated. This new analysis also shows that these stars were the only sources needed to account for reionising atoms in the cosmos, having completed half of this process when the Universe had reached an age of 700 million years.
Large Hadron Collider (LHC) performance surpasses expectations; results confirm the Higgs particle, show "bump" appears to be a statistical fluctuation, and offer insight into quark-gluon plasma at high energies complementary to those explored at the Relativistic Heavy Ion Collider (RHIC).
Scientists have announced an exciting new result that could improve our understanding of the behavior of neutrinos. Neutrinos have previously been detected in three types, called flavors -- muon, tau and electron. They also exist in three mass states, but those states don't necessarily correspond directly to the three flavors
New findings reveal why the universe is dominated by matter and why we exist and how matter and antimatter are different.
All material things appear to be made of elementary particles that are held together by fundamental forces. But what are their exact properties? Questions with cosmic implications like these drive many of the scientific efforts. Three distinguished particle physicists have joined the lab over the past months to pursue research on two particularly mysterious forms of matter: neutrinos and dark matter.
Scientists performed the first accurate determination of the thermodynamic properties of dense quark matter under violent conditions that occur during neutron star mergers, and suggest a step towards distinguishing between neutron and quark matter cores in neutron stars.
Strong coupling in specific light-matter interactions, previously believed to be a quantum phenomenon, is explained with classical models and experiments.
Physicists have successfully created one-dimensional magnetic atom chains for the first time. Their breakthrough provides a model system for basic research in areas such as magnetic data storage, as well as in chemistry.
Researchers have discovered that gallium nanoparticles can form a solid core surrounded by a liquid outer layer over a temperature span of 1000 degrees Fahrenheit. The discovery marks the first time that this stable phase coexistence phenomenon at the nanoscale has ever been directly observed.
The Askaryan Radio Array team recently published a performance review of the first two stations to come online, showing great potential for the detector to push forward understanding of the cosmos once it's fully operational.
An international team of researchers has predicted the existence of several previously unknown types of quantum particles in materials. The research represents the newest avenue in the physics of 'topological materials,' an area of science that has already fundamentally changed the way researchers see and interpret states of matter.
Scientists have calculated how it is possible to look inside the atom to image individual electron orbitals.
For the first time, researchers have coupled the nuclear spins of distant atoms using just a single electron.
A team of hundreds of physicists and astronomers has announced results from the largest-ever, three-dimensional map of distant galaxies. The team constructed this map to make one of the most precise measurements yet of the dark energy currently driving the accelerated expansion of the Universe.
Neutrinos produced in the core of a supernova are highly localized compared to neutrinos from all other known sources, researchers report. With a new estimate for an entity characterizing neutrinos, they suggest that the wave packet size is irrelevant in simpler cases.
Cosmologists have begun modelling the universe for the first time using Einstein's full general theory of relativity.
Our universe came to life nearly 14 billion years ago in the Big Bang -- a tremendously energetic fireball from which the cosmos has been expanding ever since. Today, space is filled with hundreds of billions of galaxies, including our solar system's own galactic home, the Milky Way. But how exactly did the infant universe develop into its current state, and what does it tell us about our future?
Utilizing the Atacama Large Millimeter Array, one of the most powerful telescopes in the world, researchers have peered into the feeding habits of a supermassive black hole.
When an astronomical observatory detected two black holes colliding in deep space, scientists celebrated confirmation of Einstein's prediction of gravitational waves. A team of astrophysicists wondered something else: Had the experiment found the "dark matter" that makes up most of the mass of the universe?
The supermassive black holes found at the centre of every galaxy, including our own Milky Way, may, on average, be smaller than we thought, according to new work. New research suggests that the gravitational waves produced when they merge will be harder to detect than previously assumed.
New research has enhanced scientists' understanding of how free neutrons decay into other particles. The work provides the first measurement of the energy spectrum of the photons that are released in the otherwise extensively measured process known as neutron beta decay. The details of this decay process are important because they help to explain the observed amounts of hydrogen and other light atoms created just after the Big Bang.
A team of scientists using highly sensitive radio telescopes has discovered the first complex organic chiral molecule in interstellar space. The molecule, propylene oxide (CH3CHOCH2), was found near the center of our Galaxy in an enormous star-forming cloud of dust and gas known as Sagittarius B2.
A team of physicists that visualized the internal nanostructure of an intact butterfly wing has discovered two physical attributes that make those structures so bright and colorful.
In 1998 scientists Richard Bader and Carlo Gatti proposed a mathematical model, describing the distribution of delocalized electrons in molecules. Now new research is the first to confirm the accuracy of the model, using only experimental data.
Scientists have reached another milestone in developing a promising technology for accelerating particles to high energies in short distances: They created a tiny tube of hot, ionized gas, or plasma, in which the particles remain tightly focused as they fly through it.
Hubble Space Telescope astronomers have discovered that the universe is expanding 5-9% percent faster than expected. They made the discovery by refining the universe's current expansion rate to unprecedented accuracy, reducing the uncertainty to only 2.4%. The team made the refinements by developing innovative techniques that improved the precision of distance measurements to faraway galaxies. These measurements are fundamental to making more precise calculations of how fast the universe expands with time, a value called the Hubble constant.
An intriguing alternative view is that dark matter is made of black holes formed during the first second of our universe's existence, known as primordial black holes. A scientist suggests that this interpretation aligns with our knowledge of cosmic infrared and X-ray background glows and may explain the unexpectedly high masses of merging black holes detected last year.
The origin of many of the most precious elements on the periodic table, such as gold, silver and platinum, has perplexed scientists for more than six decades. Recently, however, a team of astrophysicists has provided an answer.
Astronomers have made a 3D map of 3000 galaxies 13 billion light years from Earth, and found that Einstein's general theory of relativity is still valid.
New research discusses how people will interact with technology in the future.
The microscopic world is governed by the rules of quantum mechanics, where the properties of a particle can be completely undetermined and yet strongly correlated with those of other particles. Physicists have observed these so-called Bell correlations for the first time between hundreds of atoms.
Innovative multidisciplinary research in nuclear and particle physics and cosmology has led to the development of a new, more accurate computer code to study the early universe.
On Sept. 14, waves of energy traveling for more than a billion years gently rattled space-time in the vicinity of Earth. The disturbance, produced by a pair of merging black holes, was captured by the Laser Interferometer Gravitational-Wave Observatory (LIGO) facilities in Hanford, Washington, and Livingston, Louisiana. This event marked the first-ever detection of gravitational waves and opens a new scientific window on how the universe works.
Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.
Scientists at The University of Western Australia have discovered new technology which could mean that instead of being detected a billion light years away, gravitational waves may be identified throughout 'the observable universe'.
Moving bodies can be attracted to each other, even when they're quite far apart and separated by many other objects: That, in a nutshell, is the somewhat unexpected finding by a team of researchers at MIT.
Astrophysicists have found a simple formula for the maximum mass of a rotating neutron star and hence answered a question that had been open for decades.
Astrophysicists have revealed details of how supermassive black holes formed 13 billion years ago, and it's not from normal (stellar size) black holes growing to supermassive proportions.
New results from NANOGrav -- the North American Nanohertz Observatory for Gravitational Waves -- establish astrophysically significant limits in the search for low-frequency gravitational waves. This result provides insight into how often galaxies merge and how those merging galaxies evolve over time. To obtain this result, scientists required an exquisitely precise, nine-year pulsar-monitoring campaign conducted by two of the most sensitive radio telescopes on Earth, the Green Bank Telescope in West Virginia and the Arecibo Observatory in Puerto Rico.
Simulations have revealed for the first time exactly how these black holes formed 700 million years after the Big Bang.
Researchers have found the fastest winds ever seen at ultraviolet wavelengths near a supermassive black hole. Some are reaching as fast as 200 million kilometers, equivalent to a category 77 hurricane. And there may be even faster quasar winds. As matter spirals toward a black hole, some is blown away. These are the winds that we are detecting, says an astronomer.
Researchers have adapted a technology developed for solar energy in order to selectively remove one of the trickiest and most-difficult-to-remove elements in nuclear waste pools across the country, making the storage of nuclear waste safer and nontoxic - and solving a decades-old problem.
There are indications that we might never see the universe's mysterious dark matter. Now researchers turn this somehow depressing scenario into an advantage and propose a new model for what dark matter might be -- and how to test it.
The universe is constantly expanding. But how does our universe evolve? Physicists have now developed a new code of numerical simulations that offers a glimpse of the complex process of the formation of structures in the universe. Based on Einstein's equations, they were able to integrate the rotation of space-time into their calculations and calculate the amplitude of gravitational waves.
The fundamental constants of nature—such as the speed of light, Planck's constant, and Newton's gravitational constant—are thought to be constant in time, as their name suggests. But scientists have questioned this assumption as far back as 1937, when Paul Dirac hypothesized that Newton's gravitational constant might decrease over time.
It was 1905, and Albert Einstein had just turned theoretical physics on its head by publishing a paper on what later became known as special relativity. This showed that space and time could not be considered in absolute terms: time could speed up or slow down; standard lengths could contract; and masses could increase.
(Phys.org)—In a quantum superposition, a quantum object can be in two incompatible states at the same time, which is famously illustrated by Schrödinger's dead-and-alive cat. Recent research has shown that it's possible to have a superposition not only of incompatible states, but also of incompatible orders of events. We often think of events occurring in a definite chronological order, with event A happening (and causing) event B, or vice versa. But in certain quantum processes, events don't happen in a single definite order, but instead both orders (A before B, and B before A) occur at the same time. This counterintuitive superposition-like phenomenon is called "causal nonseparability."
Researchers share the first measurements of the attractive force between antiprotons. The discovery gives physicists new ways to look at the forces that bind matter and antimatter.
When a kitchen sponge adsorbs water into its pores, it softens and expands. Now in a new study published in The Journal of Physical Chemistry Letters, scientists have discovered that, when microporous materials adsorb fluid, they initially soften but then stiffen as they adsorb more fluid. It's as if soaking your kitchen sponge in water eventually caused it to harden. "When materials have pore spaces that are really small (close to molecular dimensions), the physics is totally different than what we know from an everyday perspective," coauthor François-Xavier Coudert, a researcher at CNRS & Chimie ParisTech, told Phys.org. "We need to think differently at the nanometer scale, and not make assumptions based on our intuition."
Lithium ion batteries (LIBs) are a class of rechargeable battery types in which lithium ions move from the negative electrode to the positive electrode during discharge and back when charging.
The internal workings of fuel cells vary, but basically all types mix hydrogen and oxygen to produce a chemical reaction that delivers usable electricity and exhausts ordinary water as a by-product. One of the most efficient types is the proton exchange membrane (PEM) fuel cell, which operates at low enough temperatures to be used in homes and vehicles.
An international group of physicists has traced the origin of an electromagnetic interaction to the Dirac equation, a fundamental equation of quantum physics.
Mathematicians investigating one of science's great questions -- how to unite the physics of the very big with that of the very small -- have discovered that when the understanding of complex networks such as the brain or the Internet is applied to geometry the results match up with quantum behavior.
Why did anti-matter disappear almost completely from our universe, whereas matter did not? Scientists are attempting to solve this mystery at the European research institute at CERN. Now they published the most precise measurement of the properties of light atomic nuclei and anti-nuclei ever made.
A team of scientists have measured a bizarre effect in quantum physics, in which individual particles of light are said to have been 'squeezed' -- an achievement which at least one textbook had written off as hopeless.
A team of physicists has found new hints of particles -- leptons, to be more precise -- being treated in strange ways not predicted by the Standard Model. The discovery could prove to be a significant lead in the search for non-standard phenomena.
Physicists suggest a new way to look for dark matter: They believe that dark matter particles annihilate into so-called dark radiation when they collide. If true, then we should be able to detect the signals from this radiation.
Astronomers studying more than 200,000 galaxies have measured the energy generated within a large portion of space more precisely than ever before. This represents the most comprehensive assessment of the energy output of the nearby Universe. They confirm that the energy produced in a section of the Universe today is only about half what it was two billion years ago and find that this fading is occurring across all wavelengths from the ultraviolet to the far infrared. The Universe is slowly dying.
A nuclear physicist and an archaeologist at the University of York have joined forces to produce a unique appraisal of the cultural significance of one of the world's most important locations for scientific inquiry
Astrophysicists have developed a new method for calculating the effect of Rayleigh scattering on photons, potentially allowing researchers to better understand the formation of the Universe.
The bizarre nature of reality as laid out by quantum theory has survived another test, with scientists performing a famous experiment and proving that reality does not exist until it is measured. Physicists have conducted John Wheeler's delayed-choice thought experiment, which involves a moving object that is given the choice to act like a particle or a wave. The group reversed Wheeler's original experiment, and used helium atoms scattered by light.
Researchers at the world's biggest particle collider said they had observed an extremely rare event—the decay of the neutral B meson into a pair of muons, the heavy cousins of electrons. The results provide further support for the so-called Standard Model, the conceptual framework for the particles and forces that constitute the cosmos, they said in the journal Nature.
At first glance, there is not the slightest doubt: to us, the universe looks three dimensional. But one of the most fruitful theories of theoretical physics in the last two decades is challenging this assumption. The "holographic principle" asserts that a mathematical description of the universe actually requires one fewer dimension than it seems. What we perceive as three dimensional may just be the image of two dimensional processes on a huge cosmic horizon.
Quantum particles behave in strange ways and are often difficult to study experimentally. Using mathematical methods drawn from game theory, physicists have shown how bosons, which like to enter the same state, can form multiple groups.
A group of unusual giant black holes may be consuming excessive amounts of matter, according to a new study. This finding may help astronomers understand how the largest black holes were able to grow so rapidly in the early Universe
Surprising gravitational similarities between spiral and elliptical galaxies have been discovered by an international team, including astronomers from Swinburne University of Technology, implying the influence of hidden forces.
Imagine an instrument that can measure motions a billion times smaller than an atom that last a millionth of a second. Fermilab's Holometer is currently the only machine with the ability to take these very precise measurements of space and time, and recently collected data has improved the limits on theories about exotic objects from the early universe.
In 1941, Russian physicist Andrey Kolmogorov developed a theory of turbulence that has served as the basic foundation for our understanding of this important naturally occurring phenomenon. Turbulence occurs when fluid flow is characterized by chaotic physical changes. Kolmogorov's theory has been interpreted to imply that transitions from one state of turbulence to another must be a smooth evolution because very intense fluctuations that are part of the process itself would smooth out anything sharp. Now, however, a new experiment disproves this interpretation of Kolmogorov's theory.
Shortly following the Big Bang, the Universe was filled with a chaotic primordial soup of quarks and gluons, particles which are now trapped inside of protons and neutrons. Study of this quark-gluon plasma requires the use of the most advanced theoretical and experimental tools. Physicists have taken one crucial step towards a better understanding of the plasma and its properties.
Theoretical physicists are about to report on a controversial discovery that they say contradicts the work of researchers over the decades. The discovery concerns the conventional approach toward bosonization-debosonization. The finding could affect calculations regarding the future of quantum computers as well as your electronic devices as they become smaller, faster and more advanced.
A quantum version of General Relativity demonstrates that dark energy and dark matter are different manifestations of gravity. The theory calculates the precise value of the cosmological constant, derives the baryonic Tully-Fisher relation, gives a quantum description of Black Holes and calculates the baryonic mass content of the observable universe.
Most of the laws of nature treat particles and antiparticles equally, but stars and planets are made of particles, or matter, and not antiparticles, or antimatter. That asymmetry, which favors matter to a very small degree, has puzzled scientists for many years. Physicists offer a possible solution to the mystery of the origin of matter in the universe.
Most of the laws of nature treat particles and antiparticles equally, but stars and planets are made of particles, or matter, and not antiparticles, or antimatter. That asymmetry, which favors matter to a very small degree, has puzzled scientists for many years.
The Planck collaboration has released data from four years of observation by the European Space Agency's Planck spacecraft. The aim of the Planck mission is to study the Cosmic Microwave Background, the light left over from the Big Bang. The measurements, taken in nine frequency bands, were used to map not only the temperature of the radiation but also its polarization, which provides additional information about both the very early Universe (when it was 380,000 years old) and our Galaxy's magnetic field.
New research has uncovered additional second laws of thermodynamics which complement the ordinary second law of thermodynamics, one of the most fundamental laws of nature. These new second laws are generally not noticeable except on very small scales, at which point, they become increasingly important.
A new study is providing evidence for the presence of dark matter in the innermost part of the Milky Way, including in our own cosmic neighborhood and the Earth's location. The study demonstrates that large amounts of dark matter exist around us, and also between us and the Galactic center. The result constitutes a fundamental step forward in the quest for the nature of dark matter.
Can a penalty kick simultaneously score a goal and miss? For very small objects, at least, this is possible: according to the predictions of quantum mechanics, microscopic objects can take different paths at the same time. The world of macroscopic objects follows other rules: the football always moves in a definite direction. But is this always correct? Physicists of the University of Bonn have constructed an experiment designed to possibly falsify this thesis. Their first experiment shows that Caesium atoms can indeed take two paths at the same time.
Ultracold atomic gases have been widely considered as ideal platforms for quantum simulation. Thanks to the clean environment and the highly tunable parameters in these systems, many interesting physical models can be simulated using cold atomic gases, and various novel many-body states have been prepared and probed experimentally. The recent experimental realization of synthetic gauge field in ultracold atomic gases has significantly extended the horizon of quantum simulation with cold atoms. As a special form of synthetic gauge field, synthetic spin-orbit coupling has attracted much attention recently.
In a new paper accepted by the journal Astroparticle Physics, Robert Ehrlich, a recently retired physicist from George Mason University, claims that the neutrino is very likely a tachyon or faster-than-light particle. There have been many such claims, the last being in 2011 when the "OPERA" experiment measured the speed of neutrinos and claimed they travelled a tiny amount faster than light. However, when their speed was measured again the original result was found to be in error – the result of a loose cable no less.
Electrons split into electrical charge and magnetic moment in a two-dimensional model, a study has shown for the first time. The discovery marks a new understanding in the discovery of exotic materials such as high-temperature superconductors.
Electron states in solids are responsible for many material properties, such as color and electrical conductivity. However, because of their confinement within the crystal, it is very difficult to study the quantum physical properties of the electrons in detail. Konstantin Bliokh and Franco Nori from the RIKEN Center for Emergent Matter Science, in collaboration with researchers in Austria, have now successfully measured free electron properties equivalent to those in solids for the first time using vortex electron beams formed by a transmission electron microscope.
A new theory of quantum mechanics was developed by Bill Poirier, a chemical physicist. The theory discusses parallel worlds' existence and the quantum effects observed in nature.
Physicists have discovered two never-before-seen baryonic particles. The finding is expected to have a major impact on the study of quark dynamics
Physicists may now be able to explain why the universe did not collapse immediately after the Big Bang. Studies of the Higgs particle -- discovered at CERN in 2012 and responsible for giving mass to all particles -- have suggested that the production of Higgs particles during the accelerating expansion of the very early universe (inflation) should have led to instability and collapse.
Are the fundamental constants really constant? Recent investigations have shown that one essential fundamental constant -- namely the mass ratio of protons to electrons -- can have changed only by a maximum of one part in a million over the age of our solar system (i.e. extrapolated over approx. 5 billion years). Previously, scientists deemed the possible changes to be twice as high. To obtain this result, physicists from PTB compared caesium and ytterbium atomic clocks with each other for 7 years.
For years physicists have been looking for the universe's elusive dark matter, but so far no one has seen any trace of it. Maybe we are looking in the wrong place? Now physicists propose a new technique to detect dark matter.
Physicists have discovered two never-before-seen baryonic particles. The finding is expected to have a major impact on the study of quark dynamics.
A trio of researches with Université Paris Diderot has found that viscoelastic fluids spontaneously form wings which in turn cause the formation of geometric shapes when the fluid is shot out of a jet at high speed. In their paper published in the journal Physical Review Letters, Henri Lhuissier, Baptiste Néel and Laurent Limat describe the attributes of the fluids as they were tested and observed in their lab.
Applying a thin film of metallic oxide significantly boosts the performance of solar panel cells—as recently demonstrated by Professor Federico Rosei and his team at the Énergie Matériaux Télécommunications Research Centre at Institut national de la recherche scientifique (INRS). The researchers have developed a new class of materials comprising elements such as bismuth, iron, chromium, and oxygen. These "multiferroic" materials absorb solar radiation and possess unique electrical and magnetic properties. This makes them highly promising for solar technology, and also potentially useful in devices like electronic sensors and flash memory drives. The results of this research are discussed in an article published in Nature Photonics by researcher and lead author Riad Nechache
The characterization of individual components in an unknown crystalline powder mixture is a challenge that has eluded scientists for many years. Now, A*STAR researchers have for the first time invented a methodology to accurately determine the crystal structures present in such mixtures.
Instead of WIMPS or axions, dark matter may be made of macroscopic objects as small as a few ounces up to the size of a good asteroid, and probably as dense as a neutron star or the nucleus of an atom, researchers suggest.
The seemingly simple process of phase changes -- those transitions between states of matter -- is more complex than previously known. New work reveals the need to rethink one of science's building blocks and, with it, how some of the basic principles underlying the behavior of matter are taught in our classrooms.
Last year CERN announced the finding of a new elementary particle, the Higgs particle. But maybe it wasn't the Higgs particle, maybe it just looks like it. And maybe it is not alone.
Electrons are elementary particles -- indivisible, unbreakable. But new research suggests the electron's quantum state -- the electron wave function -- can be separated into many parts. That has some strange implications for the theory of quantum mechanics.
Physicists have made important discoveries regarding Bs meson particles -- something that may explain why the Universe contains more matter than antimatter.
The first potential indication of direct detection of dark matter -- something that has been a mystery in physics for over 30 years -- has been attained. Astronomers found what appears to be a signature of 'axions', predicted 'dark matter' particle candidates.
How can two clumps of matter pass through each other without sharing space? Physicists have documented a strange disappearing act by colliding Bose Einstein condensates that appear to keep their distance even as they pass through one another.
For almost 400 years, mercury gauges have prevailed as the most accurate way to measure pressure. Now, within weeks of seeing "first light," a novel pressure-sensing device has surpassed the performance of the best mercury-based techniques in resolution, speed, and range at a fraction of the size. The new instrument, called a fixed-length optical cavity (FLOC), works by detecting subtle changes in the wavelength of light passing through a cavity filled with nitrogen gas.
Researchers led by Dr. Sebastian Slama of Tübingen University's Institute of Physics have succeeded in directing the fluorescence of ultracold atoms into surface plasmons – light waves oscillating across a metal surface. Quantum physicists aim to create tiny systems in which things such as the interplay of light and matter may be observed at the level of individual photons. Such controlled systems hold the promise of applications such as transistors and switches depending on a single photon. The results have been published online in Nature Physics.
A unique magnet developed by the Florida State University-headquartered National High Magnetic Field Laboratory (MagLab) and Germany's Helmholtz Centre Berlin (HZB) has reached a new world record for a neutron scattering magnet.
Electrons are elementary particles -- indivisible, unbreakable. But new research suggests the electron's quantum state -- the electron wave function -- can be separated into many parts. That has some strange implications for the theory of quantum mechanics.
For magnetic fusion energy to fuel future power plants, scientists must find ways to control the interactions that take place between the volatile edge of the plasma and the walls that surround it in fusion facilities. Such interactions can profoundly affect conditions at the superhot core of the plasma in ways that include kicking up impurities that cool down the core and halt fusion reactions.
—Schrödinger's famous thought experiment in which a cat hidden in a box can be both dead and alive at the same time demonstrates the concept of superposition on the macroscopic scale. However, the existence of such "cat states" (or simply "Cats") would be problematic in reality, as cat states not only go against common sense, but also pose problems for understanding gravity and spacetime.
Researchers have succeeded in simultaneously observing the reorganizations of atomic positions and electron distribution during the transformation of the “smart material” vanadium dioxide from a semiconductor into a metal – in a timeframe a trillion times faster than the blink of an eye
Physicists have made important discoveries regarding Bs meson particles -- something that may explain why the Universe contains more matter than antimatter.
Thermodiffusion, also called the Soret effect, is a mechanism by which an imposed temperature difference establishes a concentration difference within a mixture. Two studies now provide a better understanding of such effects.
An international team of scientists have become the first ever researchers to successfully reach temperatures below minus 272.15 degrees Celsius – only just above absolute zero – using magnetic molecules. The physicists and chemists are presenting their new investigation today in the scientific journal Nature Communications. It was developed by six scientists from Bielefeld University, the University of Manchester, and the Universidad de Zaragoza.
The American Physical Society (APS) and the American Institute of Physics (AIP) announced today, on behalf of the Heineman Foundation for Research, Educational, Charitable, and Scientific Purposes, that theoretical physicist Pierre Ramond, director of the Institute for Fundamental Theory at the University of Florida, has won the 2015 Dannie Heineman Prize for Mathematical Physics—one of the highest honors for scientific investigators in that field.
Nature has developed a wide variety of methods for guiding particular cells, enzymes, and molecules to specific structures inside the body: White blood cells can find their way to the site of an infection, while scar-forming cells migrate to the site of a wound. But finding ways of guiding artificial materials within the body has proven more difficult.
Standard quantum theory places no limit on particle size and current experiments use larger and larger particles, which exhibit wave-like behaviour. However, at these masses experiments begin to probe extensions to standard quantum mechanics, which describe the apparent quantum-to-classical transition.
How did life originate? And can scientists create life? These questions not only occupy the minds of scientists interested in the origin of life, but also researchers working with technology of the future. If we can create artificial living systems, we may not only understand the origin of life - we can also revolutionize the future of technology.
The Holy Grail of quantum cryptography – beyond delivering security that cannot be classically achieved – is guaranteeing unconditional security when the untrusted quantum devices are involved. While this goal has been studied since the early 1990s, a robust solution has proven elusive. Although Jonathan Barrett and his co-authors published2,3 a strong Device-Independent Quantum Key Distribution (DIQKD) security guarantee in 2005, it focused on a weaker set of constraints than those imposed by quantum mechanics – specifically, the no-signaling property dictated by special relativity – which thereby yielded stronger results
Like dancers swirling on the dance floor with bystanders looking on, protons and neutrons that have briefly paired up in the nucleus have higher-average momentum, leaving less for non-paired nucleons. Using data from nuclear physics experiments carried out at the Department of Energy's Thomas Jefferson National Accelerator Facility, researchers have now shown for the first time that this phenomenon exists in nuclei heavier than carbon, including aluminum, iron and lead.
Astrophysical jets are counted among our Universe's most spectacular phenomena: From the centers of black holes, quasars, or protostars, these rays of matter sometimes protrude several light years into space. Now, for the first time ever, an international team of researchers has successfully tested a new model that explains how magnetic fields form these emissions in young stars. Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) were part of this research. Their findings have been published in the journal Science. The insights gleaned from this research may even apply to cancer therapy.
Energy loss in optical systems, such as lasers, is a chief hindrance to their performance and efficiency, and it occurs on an ongoing, frustrating basis.
Particle physicists have a hard time identifying all the elementary particles created in their particle accelerators. But now researchers at Chalmers University of Technology have designed a material that makes it much easier to distinguish the particles.
Cutting-edge paper by Professor George Fraser – who tragically died in March this year – and colleagues at the University of Leicester provides first potential indication of direct detection of Dark Matter – something that has been a mystery in physics for over 30 years.
The central mystery of quantum mechanics is that small chunks of matter sometimes seem to behave like particles, sometimes like waves. For most of the past century, the prevailing explanation of this conundrum has been what's called the "Copenhagen interpretation" -- which holds that, in some sense, a single particle really is a wave, smeared out across the universe, that collapses into a determinate location only when observed. But some founders of quantum physics -- notably Louis de Broglie -- championed an alternative interpretation, known as "pilot-wave theory," which posits that quantum particles are borne along on some type of wave. According to pilot-wave theory, the particles have definite trajectories, but because of the pilot wave's influence, they still exhibit wavelike statistics. Now a professor of applied mathematics believes that pilot-wave theory deserves a second look.
Although the concept of "steering" in quantum mechanics was proposed back in 1935, it is still not completely understood today. Steering refers to the ability of one system to nonlocally affect, or steer, another system's states through local measurements
Observing the quantum behavior of light is a big part of Alan Migdall's research at the Joint Quantum Institute. Many of his experiments depend on observing light in the form of photons—-the particle complement of light waves—-and sometimes only one photon at a time, using "smart" detectors that can count the number of individual photons in a pulse. Furthermore, to observe quantum effects, it is normally necessary to use a beam of coherent light, light for which knowing the phase or intensity for one part of the beam allows you to know things about distant parts of the same beam.
Finding the Higgs boson at CERN involved an exciting chain of events and sharing it with the wider public through the media was also a journey of discovery, Prof. Jon Butterworth told an audience at the IOP's London centre on 2 October.
In his lecture, "Smashing physics: inside the world's biggest experiment", Prof. Butterworth explained why a facility the size of CERN was needed to find the Higgs, what the Higgs is and how it was detected, as well as the implications of the results for further research.
The stability of an atomic nucleus strongly depends on the number of protons and neutrons it contains. Some nuclei can, in principle, live forever, whereas others last only a fraction of a second before decaying into different nuclei. Hiroshi Watanabe from the RIKEN Nishina Center for Accelerator-Based Science and a long list of co-workers from Japan and around the world have now identified a long-lived metastable state in a neutron-rich nucleus that helps build a better picture of the forces that hold matter together
Yesterday I talked about the weirdness of neutrinos, specifically that there three types of neutrinos (known as flavors), and they can oscillate between different flavors due to the quantum fuzziness of their masses. If you go back and read that post, you'll find its a pretty bizarre model that seems to assume a great deal just to solve what is known as the solar neutrino problem. So how could we possibly know that such a model is correct?
The special theory of relativity of Albert Einstein and quantum electrodynamics, which was formulated by, among others, Richard Feynman, are two important fundaments of modern physics. In cooperation with colleagues from several international universities and institutes, the research group of Professor Wilfried Nörtershäuser (Institute for Nuclear Physics, TU Darmstadt) re-examined these theories in experiments at the GSI Helmholtz Center for Heavy Ion Research.
Scientists of the Planck collaboration, and in particular the Trieste team, have conducted a series of in-depth checks on the discovery recently publicized by the Antarctic Observatory, which announced last spring that it had detected some direct effects of gravitational waves on cosmic microwave background radiation, a potentially groundbreaking discovery in the field of cosmology. Analysis of the Planck satellite data demonstrates that the effect of contaminating sources, such as gases from our galaxy, cannot be ruled out. Read more at: http://phys.org/news/2014-09-gravitational-planck.html#jCp
Atoms are made of electrons, protons and neutrons. Protons and neutrons are in turn made up of quarks. These are just some of the elementary particles that make up the foundation of modern particle physics. But how do we know about these particles when we can't see atoms directly, much less their constituents? One of the early methods was through a device known as a cloud chamber, and it is quite a clever invention.
The idea that the laws of physics and its fundamental constants do not depend on local circumstances is called the equivalence principle. This principle is a cornerstone to Einstein's theory of general relativity. To put the principle to the test, FOM physicists working at the LaserLaB at VU University Amsterdam determined whether one fundamental constant, the mass ratio between protons and electrons , depends on the strength of the gravitational field that the particles are in. Read more at: http://phys.org/news/2014-09-physical-constant-strong-gravitational-fields.html#jCp
The work took nearly four years to complete and it opens a fundamentally new direction in photonics – with far-reaching potential consequences for the control of photons in optical fiber channels. Read more at: http://phys.org/news/2014-09-physicists-ghz-photon.html#jCp
Within physics there are certain physical quantities that play a central role. These are things such as the mass of an electron, or the speed of light, or the universal constant of gravity. We aren't sure why these constants have the values they do, but their values uniquely determine the way our universe works. For example, if the mass of electrons were smaller, atoms would be smaller. If the gravitational constant were larger, you'd need less mass to create a black hole, and neutron stars might not exis Read more at: http://phys.org/news/2014-09-variables-nature.html#jCp
Astrophysicists believe that about 80 percent of the substance of our universe is made up of mysterious "dark matter" that can't be perceived by human senses or scientific instruments.
The physical behavior of materials is strongly governed by the many electrons which can interact and move inside any solid. While an individual electron is a very simple object, carrying only mass, electric charge, and an internal rotation known as "spin", the collective behavior of many interacting electrons can be very complex, and understanding it is the key to understanding the properties of the material. Read more at: http://phys.org/news/2014-09-ultracold-atoms-exceptional-symmetry.html#jCp
A unique experiment at the U.S. Department of Energy's Fermi National Accelerator Laboratory called the Holometer has started collecting data that will answer some mind-bending questions about our universe -- including whether we live in a hologram. Read more at: http://archaeologynewsnetwork.blogspot.fr/2014/08/new-fermilab-experiment-will-test.html#.U_9BYWMrOpM Follow us: @ArchaeoNewsNet on Twitter | groups/thearchaeologynewsnetwork/ on Facebook
The field of astrophysics has a stubborn problem and it's called lithium. The quantities of lithium predicted to have resulted from the Big Bang are not actually present in stars. But the calculations are correct – a fact which has now been confirmed for the first time in experiments conducted at the underground laboratory in the Gran Sasso mountain in Italy. As part of an international team, researchers from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) studied how much lithium forms under Big Bang conditions. The results were published in Physical Review Letters. Read more at: http://phys.org/news/2014-08-big-conditions-lithium-problem.html#jCp
Researchers from the FOM Foundation and University of Groningen have found a way to preserve spin information for much longer than previously possible. They isolated the spin information from the influence of the outside world in a nanoscale graphene device, in which they can easily manipulate the information with electric fields Read more at: http://phys.org/news/2014-08-physicists-graphene.html#jCp
New University of Adelaide Future Fellow Dr Martin White is starting a research project that has the potential to redirect the experiments of thousands of physicists around the world who are trying to identify the nature of dark matter. Read more at: http://phys.org/news/2014-08-dark_1.html#jCp
New measurements of atomic-scale magnetic behavior in iron-based superconductors by researchers at the Department of Energy's Oak Ridge National Laboratory and Vanderbilt University are challenging conventional wisdom about superconductivity and magnetism. Read more at: http://phys.org/news/2014-08-scientists-uncover-clues-role-magnetism.html#jCp
The tiny titans in question are bits of strontium monofluoride, dropped to 2.5 thousandths of a degree above absolute zero through a laser cooling and isolating process called magneto-optical trapping (MOT). Read more at: http://phys.org/news/2014-08-world-coolest-molecules.html#jCp
Physicists have observed the first direct evidence of symmetry in the magnetic properties -- or nuclear 'spins' -- of atoms. The advance could spin off practical benefits such as the ability to simulate and better understand exotic materials such as superconductors.
New supercomputing calculations provide the first evidence that particles predicted by the theory of quark-gluon interactions but never before observed are being produced in heavy-ion collisions at the Relativistic Heavy Ion Collider.
The influence of the Higgs boson and its field (inset) on cosmological inflation could manifest in the observation of gravitational waves by the BICEP2 telescope (background). Credit: the BICEP2 Collaboration (background); © 2014 Fedor Bezrukov, RIKEN–BNL Research Center (inset) Read more at: http://phys.org/news/2014-08-higgs-boson-earliest-expansion-universe.html#jCp
Researchers have made the first direct observations of free-electron Landau states -— a form of quantized states that electrons adopt when moving through a magnetic field- — and found that the internal rotational dynamics of quantum electrons, or how they move through the field, is surprisingly different from the classical model, and in line with recent quantum-mechanical predictions.
The Planck Telescope allowed physicists to draw the most detailed map of the first light emitted after the Big Bang. Some of its features do not entirely fit the standard cosmological theory, but scientists have discovered that these anomalies could be explained by how the data was processed.
Neutrinos, also known as ‘ghost particles’ because they barely interact with other particles or their surroundings, are massless particles according to the standard model of particle physics. However, there is a lot of evidence that their mass is in fact non-zero, but it remains unmeasured. In cosmology, neutrinos are suspected to make up a fraction —- small but important -— of the mysterious dark matter, which represents 90% of the mass of the galaxy. Modifying the standard cosmological model in order to include fairly massive neutrinos does not explain all the physical observations simultaneously.
When a two-body relation becomes a three-body relation, the behavior of the system changes and typically becomes more complex. While the basic physics of two interacting particles is well understood, the mathematical description of a three- or many-body system becomes increasingly difficult, such that calculating the dynamics can blast the capacities of even modern supercomputers. However, under certain conditions, the quantum mechanical three-body problem may have a universal scaling solution. The predictions of such a model have now been confirmed experimentally.
Protons and neutrons are the basic constituents of atomic nuclei. Are they distributed homogeneously, or perhaps in quartets consisting of two protons and two neutrons? Physicists have recently presented an idea how this issue may be investigated in future experiments.
The discovery of a split-second burst of radio waves by scientists using the Arecibo radio telescope in Puerto Rico provides important new evidence of mysterious pulses that appear to come from deep in outer space. Exactly what may be causing such radio bursts represents a major new enigma for astrophysicists.
In quantum physics, momentum and position are an example of conjugate variables. This means they are connected by Heisenberg's Uncertainty Principle, which says that both quantities cannot be simultaneously measured precisely. Recently, researchers have been developing novel techniques, such as 'weak measurement,' to measure both at the same time. Now physicists have shown that a technique called compressive sensing offers a way to measure both variables at the same time, without violating the Uncertainty Principle.
Nearly 100 years since Albert Einstein developed General Relativity, the theory has passed its toughest test yet in explaining the properties of observable Universe. The most precise measurements to date of the strength of gravitational interactions between distant galaxies show perfect consistency with General Relativity’s predictions.
If evidence of the Higgs boson revealed two years ago was the smoking gun, particle physicists have now found a few of the bullets. The European Organization for Nuclear Research (CERN) has just published research that details evidence of the direct decay of the Higgs boson to fermions, among the particles anticipated by the Standard Model of physics. The finding fits what researchers expected to see amid the massive amount of data provided by the Large Hadron Collider (LHC).
For the first time, scientists from the CMS experiment on the Large Hadron Collider (LHC) at CERN have succeeded in finding evidence for the direct decay of the Higgs boson into fermions. Previously, the Higgs particle could only be detected through its decay into bosons. As a group of elementary particles, fermions form the matter while bosons act as force carriers between fermions.
Following a thorough peer-review process, the researchers who previously announced the detection of B-mode polarization in a patch of the microwave sky have published their findings. Their research provides some evidence that the signals they have found may be the result of gravitational waves from the earliest moments of the universe's existence and thus might constitute the first observation of phenomena from the rapid expansion of the universe known as the inflationary period.
Einstein's theory of relativity envisions time as a spatial dimension, like height, width, and depth. But unlike those other dimensions, time seems to permit motion in only one direction: forward. This directional asymmetry -- the "arrow of time" -- is something of a conundrum for theoretical physics.
A change of models demystifies anomalous particle behavior at very low temperatures, supporting that the third law of thermodynamics cannot be violated. In theory, the laws of physics are absolute. However, when it comes to the laws of thermodynamics —- the science that studies how heat and temperature relate to energy -— there are times where they no longer seem to apply.
Today, we can measure the position of an object with unprecedented accuracy, but the uncertainty principle places fundamental limits on our ability to measure. Noise that results from of the quantum nature of the fields used to make measurements imposes what is called the 'standard quantum limit.' This background noise keeps us from knowing an object's exact location, but a recent study provides a solution for rerouting some of that noise away from the measurement.
Astrophysicists have measured the minute gravitational distortions in polarized radiation from the early universe and discovered that these ancient microwaves can provide an important cosmological test of Einstein's theory of general relativity.
Scientists have shown for the first time the maximum theoretical limit of energy needed to control the magnetization of a single atom. The fundamental work can have great implications for the future of magnetic research and technology.
Move over, Matrix - astronomers have done you one better. They have created the first realistic virtual universe using a computer simulation called 'Illustris.' Illustris can recreate 13 billion years of cosmic evolution in a cube 350 million light-years on a side with unprecedented resolution.
Scientists have discovered an indicator of when re-ionization of the primordial Universe began. The team used the Faint Object Camera and Spectrograph (FOCAS) mounted on the Subaru Telescope to thoroughly study the visible wavelength spectrum of the afterglow of a gamma-ray burst, which is a violent explosion of a massive star. Direct measurement of the absorption features in the spectrum of the afterglow toward GRB 130606A, located at a great distance, revealed the proportion of neutral hydrogen gas absorbing the light in its vicinity. This finding provides the best estimate of the amount of such neutral gas in the early universe. The team's research means that scientists can now narrow down the time when the universe was beginning to re-ionize after its dark age.
The universe we can see is made up of thousands of millions of galaxies, each containing anywhere from hundreds of thousands to hundreds of billions of stars. Large numbers of galaxies are elliptical in shape, red and mostly made up of old stars. Another (more familiar) type is the spiral, where arms wind out in a blue thin disk from a central red bulge. On average stars in spiral galaxies tend to be much younger than those in ellipticals. Now a group of astronomers has found a (relatively) simple relationship between the color of a galaxy and the size of its bulge: the more massive the bulge, the redder the galaxy.
The recent discovery of the Higgs boson has confirmed theories about the origin of mass and, with it, offered the potential to explain other scientific mysteries. But, scientists are continually studying other, less-understood forces that may also shed light on matters not yet uncovered. Among these is quantum turbulence.
Scientists have made novel measurements of the structure of the universe when it was only about 3 billion years old, using quasars collected by the Baryon Oscillation Spectroscopic Survey (BOSS). Results include the most precise measurement of expansion since galaxies formed. BOSS, the largest component of the third Sloan Digital Sky Survey, pioneered the use of quasars to chart universal expansion and the role of dark energy.
A new study of gamma-ray light from the center of our galaxy makes the strongest case to date that some of this emission may arise from dark matter, an unknown substance making up most of the material universe. Using publicly available data from NASA's Fermi Gamma-ray Space Telescope, independent scientists at the Fermi National Accelerator Laboratory (Fermilab), the Harvard-Smithsonian Center for Astrophysics (CfA), the Massachusetts Institute of Technology (MIT) and the University of Chicago have developed new maps showing that the galactic center produces more high-energy gamma rays than can be explained by known sources and that this excess emission is consistent with some forms of dark matter.
Quintessence and phantom fields, two hypotheses formulated using data from satellites are among the many theories that try to explain the nature of dark energy. Now researchers suggest that both possibilities are only a mirage in the observations and it is the quantum vacuum which could be behind this energy that moves our universe. Cosmologists believe that some three quarters of the universe are made up of a mysterious dark energy which would explain its accelerated expansion. The truth is that they do not know what it could be, therefore they put forward possible solutions.
How do you grow a supermassive black hole that is a million to a billion times the mass of our sun? Astronomers do not know the answer, but a new study using data from NASA's Wide-field Infrared Survey Explorer, or WISE, has turned up what might be the cosmic seeds from which a black hole will sprout. The results are helping scientists piece together the evolution of supermassive black holes -- powerful objects that dominate the hearts of all galaxies.
For astrophysicists neutron stars are extremely complex astronomical objects. Research has demonstrated that in certain respects these stars can instead be described very simply and that they show similarities with black holes.
Australian astronomers have combined all observations of supernovae ever made to determine that the strength of gravity has remained unchanged over the last nine billion years. Newton's gravitational constant, known as G, describes the attractive force between two objects, together with the separation between them and their masses. It has been previously suggested that G could have been slowly changing over the 13.8 billion years since the Big Bang. But researchers have now analyzed the light given off by 580 supernova explosions in the nearby and far Universe and have shown that the strength of gravity has not changed.
Nobody has seen them yet; particles that are smaller than the Higgs particle. However theories predict their existence, and now the most important of these theories have been critically tested. The result: The existence of the yet unseen particles is now more likely than ever.
Scientists working on the world's leading particle collider experiments have joined forces, combined their data and produced the first joint result from Fermilab's Tevatron and CERN's Large Hadron Collider (LHC), past and current holders of the record for most powerful particle collider on Earth. Scientists from the four experiments involved -- ATLAS, CDF, CMS and DZero -- announced their joint findings on the mass of the top quark today at the Rencontres de Moriond international physics conference in Italy.
Almost 14 billion years ago, the universe we inhabit burst into existence in an extraordinary event that initiated the Big Bang. In the first fleeting fraction of a second, the universe expanded exponentially, stretching far beyond the view of our best telescopes. All this, of course, was just theory. Researchers now announce the first direct evidence for this cosmic inflation. Their data also represent the first images of gravitational waves, or ripples in space-time. These waves have been described as the "first tremors of the Big Bang." Finally, the data confirm a deep connection between quantum mechanics and general relativity.
Sixty years after Alan Turing's death, researchers have provided the first experimental evidence that validates Turing's theory of chemical morphogenesis in cell-like structures. This research could impact not only the study of biological development, and how similar patterns form in nature, but materials science as well. Turing's model could help grow soft robots with certain patterns and shapes.
Dark matter, the mysterious substance estimated to make up approximately more than one-quarter of the mass of the universe, is crucial to the formation of galaxies, stars and even life but has so far eluded direct observation. At a recent UCLA symposium attended by 190 scientists from around the world, physicists presented several analyses that participants interpreted to imply the existence of a dark matter particle. The likely mass would be approximately 30 billion electron-volts, said the symposium's organizer.
A new study examines the nature of exchange interactions between identical particles, which only occur at the quantum level. Two-particle interference has been the focus of many studies, specifically in quantum optics with photons. However, interference between two massive, identical particles is not so well understood. Scientists have now uncovered a counterintuitive result whereby particles called bosons do not behave as expected-they are overlapping, and not interfering-due to the combination of interference and so-called exchange interaction. The latter is a quantum mechanical effect that alters their symmetry when identical particles are exchanged.
Astronauts floating weightlessly in the International Space Station may appear carefree, but years of research have shown that microgravity causes changes to the human body. Spaceflight also means exposure to more radiation. Together, microgravity and radiation exposure add up to pose serious health risks. But research is not only making space safer for astronauts, it's helping to improve health care for the Earth-bound as well.
Researchers on the two main Tevatron experiments, CDF and DZero, have discovered the final predicted way of producing top quarks. Scientists have observed one of the rarest methods of producing the elementary particle -- creating a single top quark through the weak nuclear force, in what is called the "s-channel."
Researchers have provided the first English translation and an analysis of one of Albert Einstein's little-known papers, "On the cosmological problem of the general theory of relativity." Published in 1931, it features a forgotten model of the universe, while refuting Einstein's own earlier static model of 1917. In this paper, Einstein introduces a cosmic model in which the universe undergoes an expansion followed by a contraction. This interpretation contrasts with the monotonically expanding universe of the widely known Einstein-de Sitter model of 1932.
Albert Einstein accepted the modern cosmological view that the universe is expanding long after many of his contemporaries. Until 1931, physicist Albert Einstein believed that the universe was static. An urban legend attributes this change of perspective to when American astronomer Edwin Hubble showed Einstein his observations of redshift in the light emitted by far away nebulae -- today known as galaxies. But the reality is more complex. The change in Einstein’s viewpoint, in fact, resulted from a tortuous thought process. Now researchers explain how Einstein changed his mind following many encounters with some of the most influential astrophysicists of his generation.
Scientists report that recent, independent measurements have validated one of the IBEX mission's signature findings -- a mysterious "ribbon" of energy and particles at the edge of our solar system that appears to be a directional "roadmap in the sky" of the local interstellar magnetic field.
Scientists have solved a major problem with the current standard model of cosmology identified by combining results from the Planck spacecraft and measurements of gravitational lensing in order to deduce the mass of ghostly sub-atomic particles called neutrinos.
Research on first data release from Gaia-ESO project suggests the Milky Way formed by expanding out from the center, and reveals new insights into the way our Galaxy was assembled.
By observing a high-speed component of a massive galaxy cluster, Caltech/JPL scientists and collaborators have detected for the first time in an individual object the kinetic Sunyaev-Zel'dovich effect, a change in the cosmic microwave background caused by its interaction with massive moving objects.
Today the Baryon Oscillation Spectroscopic Survey (BOSS) Collaboration announced that BOSS has measured the scale of the universe to an accuracy of one percent. This and future measures at this precision are the key to determining the nature of dark energy.
Using the new capabilities of the upgraded Karl G. Jansky Very Large Array (VLA), scientists have discovered previously-unseen binary companions to a pair of very young protostars. The discovery gives strong support for one of the competing explanations for how double-star systems form.
A recent paper by Stefano Liberati from SISSA is a systematic review of the methods devised by scientists since the 90s to test Einstein's laws of Special Relativity, up to the highest observable energies. These types of tests are important: deviations from Special Relativity could in fact indicate that space-time is not continuous but grainy.
South Pole Telescope scientists have detected for the first time a subtle distortion in the oldest light in the universe, which may help reveal secrets about the earliest moments in the universe's formation.
Maybe it happens tomorrow. Maybe in a billion years. Physicists have long predicted that the universe may one day collapse, and that everything in it will be compressed to a small hard ball. New calculations from physicists at the University of Southern Denmark now confirm this prediction -- and they also conclude that the risk of a collapse is even greater than previously thought.
A colloquium paper published in The European Physical Journal D looks into the alleged issues associated with quantum theory. Berthold-Georg Englert from the National University of Singapore reviews a selection of the potential problems of the theory.
World-leading scientists will push the boundaries of studies on how to deflect asteroids and manipulate space debris, as the University of Strathclyde gets set to transform international space research.
Researchers have identified some of the underlying physics that may explain how insects can so quickly recover from a stall in midflight -- unlike conventional fixed wing aircraft, where a stalled state often leads to a crash landing.
An international team of high-energy physicists says the discovery of an electrically charged subatomic particle called Zc(4020) is a sign that they have begun to unveil a whole new family of four-quark objects.
In a new study, Dartmouth researchers rule out a controversial theory that the accelerating expansion of the universe is an illusion.
Imagine you order a delivery of several glass vases in different colors. Each vase is sent as a separate parcel. What would you think of the courier if the parcels arrive apparently undamaged, yet when you open them, it turns out that all the red vases are intact and all the green ones are smashed to pieces? Physicists from the University of Warsaw and the Gdansk University of Technology have demonstrated that when quantum information is transmitted, nature can be as whimsical as this crazy delivery man.
Potential asteroid impact on Earth can have disastrous consequences. In order to prevent such collisions, earthbound space objects must be deflected. This can be accomplished using a space probe to impact the asteroid.
An international team of scientists has provided proof of a key feature of quantum physics -- Heisenberg's error-disturbance relation -- more than 80 years after it was first suggested.
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2013 to François Englert of Université Libre de Bruxelles, Brussels, Belgium, and Peter W. Higgs of the University of Edinburgh, UK, "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider."
Two million years ago a supermassive black hole at the heart of our galaxy erupted in an explosion so immensely powerful that it lit up a cloud 200,000 light years away, a team of researchers led by the University of Sydney has revealed. The finding is an exciting confirmation that black holes can 'flicker', moving from maximum power to switching off over, in cosmic terms, short periods of time.
Two researchers at UCL Computer Science and the University of Gdansk present a new method for determining the amount of entanglement -- a quantum phenomenon connecting two remote partners, and crucial for quantum technology -- within part of a one-dimensional quantum system.
The existence of the "Hubble Bubble" may explain, at least in part, the differing measurements for the expansion and therefore the age of the universe. That is the assumption of a team of physicists headed by Prof. Dr. Luca Amendola from the Institute for Theoretical Physics at Heidelberg University. In collaboration with colleagues from the Netherlands, the Heidelberg physicists developed a theoretical model that places the Milky Way inside of this type of cosmic bubble. The researchers believe the bubble can explain some of the deviations between previous measurements and the latest ones from the Planck satellite of the European Space Agency (ESA).
No one knows for sure, but it is not at all unlikely that the universe is constructed in a very different way than the usual theories and models of today predict. The most widely used model today cannot explain everything in the universe, and therefore there is a need to explore the parts of nature which the model cannot explain. This research field is called new physics, and it turns our understanding of the universe upside down. New research now makes the search for new physics easier.
An international team of researchers, led by physicists from Lund University, has confirmed the existence of what is considered a new element with atomic number 115. The experiment was conducted at the GSI research facility in Germany. The results confirm earlier measurements performed by research groups in Russia.
The international Daya Bay Collaboration has announced new results about the transformations of neutrinos -- elusive, ghostlike particles that carry invaluable clues about the makeup of the early universe. The latest findings include the collaboration's first data on how neutrino oscillation -- in which neutrinos mix and change into other "flavors," or types, as they travel -- varies with neutrino energy, allowing the measurement of a key difference in neutrino masses known as "mass splitting."
Just how stars and black holes in the Universe are able to form from rotating matter is one of the big questions of astrophysics. What we do know is that magnetic fields figure prominently into the picture.
Astronomers have explored cold dark matter in depth and proposes new answers about the formation of galaxies and the structure of the Universe. These predictions are being contrasted with fresh data provided by the Hubble space telescope. It is estimated that only a minute fraction of the matter in the Universe is baryonic matter, which forms stars, planets and living organisms. The rest, comprising over 80%, is dark matter and energy.
Scientists propose a link between string field theory and quantum mechanics that could open the door to using string field theory as the basis of all physics. Their calculations "could solve the mystery of where quantum mechanics comes from," said a co-author.