The Peres conjecture is false!

A team of researchers has finally solved 1 of the most famous problems in quantum information physics

2014-11-05

(Press-News.org) Since 1999, the conjecture by Asher Peres, who invented quantum teleportation, has piqued the interest of many scientists in the field. According to his hypothesis, the weakest form of quantum entanglement can never result in the strongest manifestation of the phenomenon. Today, a team of researchers from the University of Geneva (UNIGE), Switzerland, and the Hungarian Academy of Sciences have proven this conjecture to be false, thus solving one of the most famous problems in quantum information physics. This news was published in Nature Communications review. The physicist Asher Peres was very interested in the phenomenon of quantum entanglement and its different manifestations. When two objects (take photons, for example) are entangled, they remain correlated regardless of the distance that separates them physically: whether they are separated by a millimetre or by several kilometres, any action done to one of them will immediately affect the other. To check whether a system is entangled, scientists test for Bell's inequality. If the experimental measurements violate Bell's inequality, this means that the two objects are entangled, and that they correspond to two manifestations, in different locations, of the same single object. This is called nonlocality. A Problematic Conjecture In 1999, Asher Peres conjectured that the weakest form of an entanglement will never result in the strongest manifestation of the phenomenon. Explanations. The violation of Bell's inequality represents the strongest form of entanglement. Two objects must indeed be strongly entangled in order for the system's experimental measurements to violate Bell's inequality. On the other hand, there also exist states with very weak entanglement. Asher Peres wondered if it would be possible to distil several wealky entangled states in order to make a strongly entangled one, as one would distil alcohol. The theory showed that this was possible, but not in every case. Certain states are in fact too weakly entangled to be distilled; this is the case of bound entanglement, which is considered the weakest form of the phenomenon. Peres therefore concluded that the weakest form of entanglement could never result in the strongest manifestation of the phenomenon, namely nonlocality. Later, a number of scientists tried to prove his conjecture. Some succeeded in a few particular cases, but none were able to demonstrate the claim in general. Peres's conjecture was therefore considered to be one of the most famous unresolved problems in the field of quantum information physics... until now. In fact, Nicolas Brunner, a physics Professor at UNIGE's Faculty of science, and Tamas Vertesi, a researcher at the Hungarian Academy of Sciences, were able to disprove Peres's conjecture. «To do so, we just had to find a counter-example,» explains Professor Brunner. «Using numerical algorithms, we showed that a bound entanglement can violate Bell's inequality, without needing to be distilled.»

INFORMATION:

ELSE PRESS RELEASES FROM THIS DATE:

Patients benefit from caregiver involvement in hospital discharge intervention

2014-11-05

Providence, RI— Results of a new study published in The American Journal of Managed Care show that the presence of a family caregiver during patient recruitment is associated with a greater rate of completion of a post hospital transitional care coaching intervention, particularly among men. Discharge is a crucial component of the hospitalization process. Patients' understanding and engagement in discharge plans greatly influence their experiences, health outcomes, such as hospital readmission, and overall costs. The study looked at discharges using the Care Transitions ...

Population boom, droughts contributed to collapse of ancient Assyrian Empire

2014-11-05

There's more to the decline of the once mighty ancient Assyrian Empire than just civil wars and political unrest. Archaeological, historical, and paleoclimatic evidence suggests that climatic factors and population growth might also have come into play. This is the opinion of Adam Schneider of the University of California-San Diego in the US, and Selim Adali of the Research Center for Anatolian Civilizations in Turkey, published in Springer's journal Climatic Change. In the 9th century BC, the Assyrian Empire of northern Iraq relentlessly started to expand into most of ...

No link found between movie, video game violence and societal violence

2014-11-05

Washington, DC (November 5, 2014) – Since the 1920s, scholars and politicians have blamed violence in movies and other media as a contributing factor to rising violence in society. Recently the responses to mass shootings in Aurora, CO and at Sandy Hook Elementary followed this theme as media consumption came into the equation. But can consumption of violent media really be a factor in real-world violence? A recent study published in the Journal of Communication by a researcher at Stetson University found that there were no associations between media violence consumption ...

Getting to the heart of the heart

2014-11-05

For years, a multidisciplinary team of Johns Hopkins researchers has tracked an elusive creature, a complex of proteins thought to be at fault in some cases of sudden cardiac death. As they report Nov. 5 in the online edition of Nature Communications, they have finally captured images of the complex. Those images reveal the connection between some genetic mutations and electrical abnormalities of the heart and provide a starting point for designing therapies. Sudden cardiac death is often caused by conditions that affect electrical signaling in the heart. Genetic studies ...

Taking a deeper look at 'ancient wing'

2014-11-05

Berlin, Germany (November, 2014) – Reconstructing ancient life has long required a certain degree of imagination. This is especially true when considering the coloration of long-extinct organisms. However, new methods of investigation are being incorporated into paleontology that may shed light (and color) on fossils. Research presented at the recent Society of Vertebrate Paleontology meeting shows the importance of using new imaging technologies in reconstructing the color of Archaeopteryx, one of the most famous and important fossils species. Ryan Carney of Brown ...

African diamond mine reveals dinosaur and large mammal tracks

2014-11-05

Berlin, Germany (November, 2014) – Unexpectedly one of the largest diamond mines in Africa, Catoca in Angola, holds 118 million year old dinosaur, crocodile and large mammal tracks. The mammal tracks show a raccoon-sized animal, during a time when most were no larger than a rat. Nearly 70 distinct tracks were recovered in the Catoca mine in Angola. All the tracks were found in a small sedimentary basin, formed about 118 Ma, during the Early Cretaceous, in the crater of a kimberlite pipe. The most important of these finds are those whose morphology is attributable ...

Jet-fueled electricity at room temperature

2014-11-05

SALT LAKE CITY, Nov. 5, 2014 – University of Utah engineers developed the first room-temperature fuel cell that uses enzymes to help jet fuel produce electricity without needing to ignite the fuel. These new fuel cells can be used to power portable electronics, off-grid power and sensors. A study of the new cells appears online today in the American Chemical Society journal ACS Catalysis. Fuel cells convert energy into electricity through a chemical reaction between a fuel and an oxygen-rich source such as air. If a continuous flow of fuel is provided, a fuel ...

Turning pretty penstemon flowers from blue to red

2014-11-05

While roses are red, and violets are blue, how exactly do flower colors change? In the case of penstemons, with over 200 species to choose from, scientists Carolyn Wessinger and Mark Rausher have now shown that turning their flowers from blue to red involves knocking out the activity of just a single enzyme involved in the production of blue floral pigments. A genetically conserved biochemical pathway produces the vivid blue pigments that they found to mutate over time to produce red. To shift into red pigment production, the enzyme flavonoid 3', 5' –hydroxylase ...

Patients with emergency-diagnosed lung cancer report barriers to seeing their GP

2014-11-05

MANY patients whose lung cancer is diagnosed as an emergency in hospital reported difficulties in previously seeing their GP, according to research presented at the National Cancer Research Institute (NCRI) Cancer Conference in Liverpool today (Tuesday). The study, carried out by researchers from the London Cancer Alliance (LCA) and King's College London, investigated around 130 patients who were diagnosed with lung cancer after attending as an emergency at one of seven hospitals in south and west London. Overall, nearly half of the patients reported that something ...

Scientists uncover potential drug to tackle 'undruggable' fault in third of cancers

2014-11-05

SCIENTISTS have found a possible way to halt one of the most common faults in many types of cancer, according to research presented at the National Cancer Research Institute (NCRI) Cancer Conference in Liverpool today (Wednesday). A team of scientists at the Max Planck Institute of Molecular Physiology in Germany has uncovered a new strategy and new potential drug to target an important signalling protein in cells called Ras, which is faulty in a third of cancers. When the Ras protein travels from the centre of a cell to the cell membrane, it becomes 'switched on' ...

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

The Peres conjecture is false!

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: