background preloader

Scientists Discover a Jewel at the Heart of Quantum Physics - Wired Science

Scientists Discover a Jewel at the Heart of Quantum Physics - Wired Science
Physicists reported this week the discovery of a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality. “This is completely new and very much simpler than anything that has been done before,” said Andrew Hodges, a mathematical physicist at Oxford University who has been following the work. The revelation that particle interactions, the most basic events in nature, may be consequences of geometry significantly advances a decades-long effort to reformulate quantum field theory, the body of laws describing elementary particles and their interactions. Interactions that were previously calculated with mathematical formulas thousands of terms long can now be described by computing the volume of the corresponding jewel-like “amplituhedron,” which yields an equivalent one-term expression. The amplituhedron itself does not describe gravity. Related:  Time MachineQuantum ShenanigansScience

Photons detected without being destroyed iStock/THINKSTOCK Measuring the properties of photons usually involves absorbing them, but a new device detects their passage and lets them fly by. One of the cornerstones of quantum theory is the principle that you cannot measure any property of an object without affecting the object itself. Indeed, detecting the very existence of a photon until now has usually meant destroying it. Physicists, however, have now devised a way to detect single photons of visible light without bringing about their demise. The conventional way to detect a single particle of light is to catch it with a sensor, absorbing its energy but destroying the particle in the process. In recent years, physicists have developed methods to extract part of the information from a particle’s quantum state — for example showing that it is more likely to be in one place than in another — in a set of methods known as weak measurement.

Quantum Effects in Biology | Controlled Quantum Dynamics Group Biologists do not take a quantum physics course during their studies because so far they were able to make sense of biological phenomena without using the counterintuitive laws of physics that govern the atomic scale. However, in recent years progress in experimental technology has revealed that quantum phenomena are relevant for fundamental biological processes such as photosynthesis, magneto-reception and olfaction. We have helped to initiate the development of this research field and are now working to discover how nature is harnessing quantum dynamics to optimize biological function. S.F. Environment assisted quantum bio-dynamics: It is remarkable that quantum phenomena can play a role in warm, wet and noisy biological systems. Environment assisted quantum bio-dynamics: Biological environments are not creating white noise but do actually possess considerable structure. J.M.

Artificial gravity Proposed Nautilus-X International space station centrifuge demo Artificial gravity is the varying (increase or decrease) of apparent gravity (g-force) via artificial means, particularly in space, but also on Earth. It can be practically achieved by the use of different forces, particularly the centripetal force and linear acceleration. The creation of artificial gravity is considered desirable for long-term space travel or habitation, for ease of mobility, for in-space fluid management, and to avoid the adverse long-term health effects of weightlessness. A number of methods for generating artificial gravity have been proposed for many years, as well as an even larger number of sci-fi approaches using both real and fictitious forces. Amusement parks make frequent use of centripetal force and linear acceleration, through roller coasters and other rides. Requirement for gravity[edit] Without g-force, space adaptation syndrome occurs in some humans and animals. Rotation[edit] Mass[edit]

Hyper-priming in cannabis users: a naturalist... [Psychiatry Res. 2010 Spooky Physics Phenomenon May Link Universe's Wormholes Wormholes — shortcuts that in theory can connect distant points in the universe — might be linked with the spooky phenomenon of quantum entanglement, where the behavior of particles can be connected regardless of distance, researchers say. These findings could help scientists explain the universe from its very smallest to its biggest scales. Scientists have long sought to develop a theory that can describe how the cosmos works in its entirety. Currently, researchers have two disparate theories, quantum mechanics and general relativity, which can respectively mostly explain the universe on its tiniest scales and its largest scales. There are currently several competing theories seeking to reconcile the pair. One prediction of the theory of general relativity devised by Einstein involves wormholes, formally known as Einstein-Rosen bridges. "This is true even when the electrons are light years apart," saidKristan Jensen, a theoretical physicist at Stony Brook University in New York.

Researchers at Brown University shattered an electron wave function A team of physicists based at Brown University has succeeded in shattering a quantum wave function. That near-mythical representation of indeterminate reality, in which an unmeasured particle is able to occupy many states simultaneously, can be dissected into many parts. This dissection, which is described this week in the Journal of Low Temperature Physics, has the potential to turn how we view the quantum world on its head. When we say some element of the quantum world occupies many states at once, what’s really being referred to is the element’s wave function. If a particle could be in position (x,y,z) in three-dimensional space, there are probabilities that it could specifically be at (x1,y1,z1) or (x2,y2,z2) and so forth, and this is represented in the wave function, which is all of these possibilities added together. Visually, we might imagine a particle in its undisturbed state looking more like a cloud than a point in space. Maris is chasing a fairly old mystery with this work.

New Study on Safety of Eating Seafood During Pregnancy | BabyMed.com Q: Is it safe to eat sea food during pregnancy? A: Conflicting nutrition advice can be confusing, particularly for pregnant women, who often feel that they must become nutritional experts overnight as they start to eat for two. In the United States pregnant and nursing women, as well as those who want to conceive, are advised to avoid certain types of seafood and to limit consumption of other varieties as a way to reduce potential ill effects from mercury and other contaminants. But a new report from a huge, ongoing research project in the United Kingdom suggests that if women skimp on seafood during pregnancy it may be detrimental to their children. The latest findings, published in 2007 in the journal the Lancet, confirm that you have to eat fish because there's so much more benefit than risk. Indeed, skimping on seafood during pregnancy appears to produce the very problems that scientists feared could occur from eating too much seafood containing mercury.

Tutkimus: Ruokavalion muutos keikauttaa suoliston mikrobit päivässä - Tiede Suoliston mikrobit reagoivat ruokavalion muutokseen paljon nopeammin kuin tähän asti on oletettu. Tuoreessa tutkimuksessa pelkälle liha- tai kasvisruokavaliolle laitettujen ihmisten suolistomikrobien voimasuhteet keikahtivat yhdessä yössä. Harvardin yliopiston tutkimus sai inspiraationsa havainnoista, joiden mukaan ruokavalion muutos näkyy hiirten suolistomikrobistossa hyvin nopeasti. He halusivat testata, onko muutos ihmisillä yhtä nopea. Asiasta ei tätä ennen ole tehty luotettavia selvityksiä. Tutkijat rekrytoivat kokeeseen kymmenen vapaaehtoista, jotka jaettiin kahteen ryhmään. Eräs vapaaehtoisista oli noudattanut vegetaristista ruokavaliota useita vuosia, mutta suostui koemielessä liharyhmään. Kaikilta vapaaehtoisilta otettiin joka päivä ulostenäyte, josta määritettiin sen sisältämät mikrobit sekä niiden geeniaktiivisuus. Tulokset osoittivat, miten ruokavalion muutos järjestää mikrobien hierarkian suolistossa uudelleen. Hämmästyttävintä oli muutoksen nopeus.

In a "Rainbow" Universe Time May Have No Beginning What if the universe had no beginning, and time stretched back infinitely without a big bang to start things off? That's one possible consequence of an idea called "rainbow gravity," so-named because it posits that gravity's effects on spacetime are felt differently by different wavelengths of light, aka different colors in the rainbow. Rainbow gravity was first proposed 10 years ago as a possible step toward repairing the rifts between the theories of general relativity (covering the very big) and quantum mechanics (concerning the realm of the very small). The idea is not a complete theory for describing quantum effects on gravity, and is not widely accepted. Nevertheless, physicists have now applied the concept to the question of how the universe began, and found that if rainbow gravity is correct, spacetime may have a drastically different origin story than the widely accepted picture of the big bang. Yet the concept has its critics.

Related: