Not all quantum properties are lost through interaction with the environment

first_img Explore further (PhysOrg.com) — One of the most well-known “rules” of quantum physics is that all quantum properties are lost due to environmental interaction. This rule, though, may not hold true in all situations. “We have discovered the first counter to this common rule,” Sabrina Maniscalco tells PhysOrg.com. Maniscalco is a researcher at the Turku Centre for Quantum Physics, University of Turku in Finland. Along with fellow researcher (and husband) Jyrki Piilo, and Ph.D. student Laura Mazzola, Maniscalco has identified evidence that some quantum correlations can remain intact. Copyright 2010 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. The results of their work are published in Physical Review Letters: “Sudden Transition between Classical and Quantum Decoherence.”“Laura really did most of the work,” Maniscalco says. “She was studying different interactions between quantum properties and the environment, and looking for different correlations in noisy quantum systems. No one expected her to find strange behavior. When she first called Jyrki and me with the result, we thought it must be a mistake.”Maniscalco and Piilo went over the data and realized that it wasn’t a mistake. “We checked the calculations again, and found that the time evolution of quantum correlations in this case remains constant for a long time. It represented a transition between classical and quantum decoherence, and the quantum property was not lost.”This particular correlation can be found, for example, in quantum systems comprising of two qubits. “These qubits, each with different properties, such as different polarizations, have to interact with a type of noise that doesn’t change the energy of the qubits,” Maniscalco explains. “Instead of changing the energy, the noise just changes the phase, such as flipping polarizations. The type of noise that we have considered is one that contains all frequencies in a way that is very similar to white noise.”While this discovery is theoretical, Maniscalco says that it has an experimental basis as well. “A very recent experiment has confirmed a type of quantum correlation that is not affected by the environment. And this is not a weird type of environment; it’s a natural environment that we could work in right now.” (For more on this experiment, see Jin-Shi Xu, et. al., “Experimental investigation of classical and quantum correlations under decoherence,” Nature Communications (April 2010). Doi:10.1038/ncomms1005.)In the last 20 years, Maniscalco points out, technology has advanced to the point where it is possible to use single atoms or photons to build quantum logic gates for future quantum computers, or perform communication, measurement and cryptography tasks. “We’ve learned that it is possible to exploit the quantumness of the microscopic state, but in order for us to succeed, the quantum properties have to remain intact for a long time. That is a challenge, since once the properties are lost through interaction with the environment, a device can’t exploit quantumness.”This discovery that certain quantum correlations are not lost in presence of the environment could lead an increased ability to exploit the quantum world for use in technological devices. Maniscalco points out that the idea that all quantum properties need not be lost through interaction with the environment presents more than interesting fundamental implications. “While this work has a surprising fundamental aspect,” she says, “it opens up a whole range of possibilities with applications in quantum technology, including computing, communications, metrology and cryptography.”Next, Maniscalco says that her group, and Piilo’s group, at the University of Turku will need to study this effect. “We need to learn the most general conditions for this behavior, and see if it holds for other environments. We are also working toward deigning a quantum protocol that uses this state, so that we can demonstrate an application of this effect in practice.”For more information, you can visit the Open Quantum Systems and Entanglement group and the Non-Markovian Processes and Complex Systems group web pages. Citation: Not all quantum properties are lost through interaction with the environment (2010, June 1) retrieved 18 August 2019 from https://phys.org/news/2010-06-quantum-properties-lost-interaction-environment.htmlcenter_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Laura Mazzola, Jyrki Piilo, and Sabrina Maniscalco, “Sudden Transition between Classical and Quantum Decoherence, Physical Review Letters (May 2010). Available online: link.aps.org/doi/10.1103/PhysRevLett.104.200401 Quantum cryptography: No Signaling and quantum key distributionlast_img read more


Carbon nanotube film restores light sensitivity to blind retinas

first_img Journal information: Nano Letters The development of artificial retinas still faces many challenges: the implants should provide long-term light sensitivity, should have high spatial resolution, should not contain wires, and should be made of materials that are biocompatible and mechanically flexible. Candidate materials include conducting polymers and quantum dot films, with each having its own advantages and disadvantages in these areas.Another approach to restoring light sensitivity involves optogenetics, in which light-sensitive proteins (bacterial opsins) are introduced into neurons in the retina. However, this method still requires an electrode to assist in light-induced stimulation of these neurons. In a new paper published in Nano Letters, researchers at Tel Aviv University, The Hebrew University of Jerusalem, and Newcastle University have found that a film containing carbon nanotubes and nanorods is particularly effective for wire-free retinal photostimulation. “The greatest significance of our work is in demonstrating how new materials (quantum rods combined with carbon nanotubes) can yield a new system suitable for efficient stimulation of a neuronal system,” coauthor Yael Hanein, Professor at Tel Aviv University, told Phys.org.The researchers showed that, when the film is attached to a chick retina at 14 days of development (at a time when the retinas are not yet light-sensitive, and so completely blind), the retinas produce a photogenerated current—a neuronal signal that can then be interpreted by the brain. In the new film structure, the nanorods are interspersed throughout a 3D porous carbon nanotube matrix, and the resulting film is then patterned onto a flexible substrate for implantation. The researchers explain that the 3D structure of the new film provides several advantages, which include high light absorbance, strong binding to neurons, and efficient charge transfer. While other candidate materials for artificial retinas, such as silicon, are rigid, nontransparent, and require an external power source, the new material does not have these problems.With these advantages, the new films look very promising for use in future artificial retina applications. The researchers also expect that the films could be improved even more with further research.”At the present, we study the new implants in vivo, attempting to demonstrate their performances over long-term implantation,” Hanein said. “We teamed up with a retina surgeon to develop an implantation and testing procedures compatible with conventional surgical practices towards attempting human trials in the future.” Carbon nanotubes combined with nanorods are used to create a light-sensitive film, potentially replacing damaged photoreceptors in the retina. Charge separation at the nanorod-nanotube interface elicits a neuronal response, which could then be interpretted by the brain. Credit: Bareket, et al. ©2014 American Chemical Society Photoelectric dye-coupled thin film as a novel type of retinal prosthesis This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. © 2014 Phys.orgcenter_img (Phys.org) —Light striking the retina in the back of the eye is the first major step in the vision process. But when the photoreceptors in the retina degenerate, as occurs in macular degeneration, the retina no longer responds to light, and the person loses some or all of their sight. However, if the retina can be made sensitive to light with the help of some type of optoelectronic implant, then vision may be restored. Citation: Carbon nanotube film restores light sensitivity to blind retinas (2014, November 11) retrieved 18 August 2019 from https://phys.org/news/2014-11-carbon-nanotube-sensitivity-retinas.html More information: Lilach Bareket, et al. “Semiconductor Nanorod-Carbon Nanotube Biomimetic Films for Wire-Free Photostimulation of Blind Retinas.” Nano Letters. DOI: 10.1021/nl5034304 Explore furtherlast_img read more


Women bag top 3 places in Smart India Hackathon at IITKGP

first_imgKolkata: Three all-woman teams have emerged as the winner and two runners-up at the Grand Finale of Smart India Hackathon 2018Hardware Edition at the IIT Kharagpur, a statement from the institute said today. The teams devised innovative prototypes in Agriculture/Agro-electronics sector which was the theme of the Hackathon at the IIT-KGP. The institute was one of the 10 nodal centres across the country for the Hackathon, each having different themes for the contending teams and would have their own winners. Also Read – Heavy rain hits traffic, flights While ‘Whistling Cookers’ team of the Avinashilingam Deemed University for Women, Coimbatore, was declared the winner at the IIT-KGP, first runner-up, Team Buddies, was from the same institution, an IIT KGP statement said today. The second runner-up was ‘Team Askurvara’ from the Silicon Institute of Technology, Bhubaneswar. The winning team designed a prototype for ‘non-destructive estimation of sugar content of fruits using visible-light imaging’, the statement said. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killed The top three winning teams won cash prizes of Rs 100,000, Rs 75,000 and Rs 50,000 respectively, it said. At the IIT-KGP, nine teams from all over the country brainstormed over the theme ‘Agriculture/Agro-Electronics’ to build their hardware solutions as a working prototype. The event at IIT-KGP saw innovations in smart drip irrigation, technology-powered mechanical harvesters and soil testing and cost-effective detection of the status of fruits and vegetables. They were among the total 150 short-listed teams in final round as the rest 141 competed at other nodal centres. The Smart India Hackathon 2018 Hardware edition was initiated by the Ministry of HRD to provide a national platform to young technical minds to showcase their innovations in devising products which can bring about significant changes in sectors like agriculture, health, clean water, waste management, automotive, smart communication and education. The event was inaugurated on June 18 by Union HRD minister, Prakash Javadekar through video-conferencing.last_img read more


22member team to scale Mt Kang Yatse in Alpinestyle expedition

first_imgDarjeeling: A team from Himalayan Mountaineering Institute (HMI), Darjeeling is all set to embark on its first ever Alpine-style expedition from August 1.A 22-member team will be climbing the Mount Kang Yatse-1 (6400 m) in Ladakh. The expedition will be formally flagged off from Darjeeling on Saturday.An Alpine-style expedition is one where no porter is used beyond the Base Camp. The expedition members carry out all activities such as load ferry, route opening and cooking among other necessary things. Also Read – Rain batters Kolkata, cripples normal life”Such expeditions are faster and are less expensive than traditional expeditions. Though it is tougher than regular expeditions, Alpine-style climbs help boost confidence,” stated Devidutta Panda, vice-principal, HMI, who is also the leader of the expedition.The expedition will be flagged off by SA Baba, Principal Secretary, Youth Service Department, Government of Bengal on Saturday.Kang Yatse — (elevation 6,400 metre) is a mountain located at the end of the Markha Valley in Ladakh. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedTwo teams will depart from Darjeeling on July 25 and August 1. The expedition will take a month from August 1. Apart from members, the 22-member team also includes instructors, 2 cooks, the Curator of HMI museum and a representative of D(HMI), MoD.”For this expedition, we are not taking help from any agency. During advance course at the HMI, we teach the students expedition planning and execution. In this expedition, the instructors will get a first hand experience of planning and executing an expedition on ground zero. There will definitely be some shortcomings from which we can learn. Many instructors have not done Alpine-style expeditions in the past,” stated the vice-principal, who is a two time Everester himself. The expedition members will be going to Delhi, Manali, Leh and then onwards to the base camp of the mountain.The successful ascent of Mount Everest on May 29, 1953, by Tenzing Norgay and Sir Edmund Hillary was a major boost to mountaineering in India.One year after this historical event, the Himalayan Mountaineering Institute was established on November 4, 1954 — a result of personal initiative of Pundit Jawaharlal Nehru, the first Prime Minister of India and Dr BC Roy, the then Chief Minister of West Bengal to promote mountaineering in India.The HMI in its sixty fourth years of existence has trained approximately 40,000 personnel including 2,000 overseas trainees. Since 1954 the Institute has organised 13 mountaineering expeditions in the Himalayan regions and overseas including the Alps under the leadership of the Institute heads.last_img read more


Flu vaccinations protect the elderly too

first_imgContrary to claims that the youth benefit more from flu vaccines, a t10-year study has found that annual influenza vaccinations can also reduce the hospitalisation rate and delay mortality among the elderly.“This study evidences protection for an elderly population for whom vaccine efficacy has been questioned,” said study co-author Stefan Gravenstein, adjunct professor of medicine and health services, policy and practice at Brown University in Rhode Island, US.  Also Read – ‘Playing Jojo was emotionally exhausting’“Annual vaccination is the only way to maximise the benefit of vaccine, no matter what the age,” Gravenstein noted. The researchers found that between 2000 and 2009, the better matched the vaccine was for the influenza strain going around, the fewer residents in US nursing home died or were hospitalised.For the study, the researchers analysed records of millions of nursing home residents. Year-to-year the ability of the vaccine to fight the flu can vary widely. Sometimes vaccine makers produce a great match that is highly protective. In other years the prevailing flu strain does not match the vaccine well. The researchers took advantage of this natural variation over the decade 2000-09 to see whether nursing home residents were better off when the match was good compared to when the match was bad.  If vaccines do not help the elderly, as some critics suggest, then nursing home residents should not fare any better when the vaccine is a good match than when it is a bad match. The results showed that vaccinations help keep some  nursing home residents alive and out of the hospital. The study was published in the Journal of the American Geriatrics Society.last_img read more


Murder accused arrested after snatching incident

first_imgKolkata: One Utpal Sarkar was arrested from Konnagar, Hooghly, on Friday night and a firearm along with one round of ammunition and 25 kg ganja was recovered from him. He has been remanded to judicial custody till Monday following his production before the local court on Saturday.According to locals, on Friday night at around 10 pm, Sarkar and his associate suddenly started snatching valuables at Kotrung area. When a good number of locals gathered and retaliated, both the accused forced a scooty rider, identified as Rahim, to take them to a safe place by showing him a one-shot gun. While fleeing the spot, Sarkar fired one round of bullet in the air to create panic.While trying to flee, the scooty ran out of petrol near the Olympic maath in Konnagar. Eventually, Rahim managed to escape as they were trying to intercept another motorcycle rider. A patrolling van, after being informed, from the Uttarpara police station arrived within a few minutes. Sarkar’s associate managed to escape on a bicycle and he tried to hide behind a nearby bush but was later forced to surrender. Following his arrest, it was found that he was carrying a one-shot gun loaded with one round of bullet and 25 kg ganja. Police sources informed that he was in the prison for the past four years as is an accused in a murder case.last_img read more


Tanning can contribute to skin ageing

first_imgWhile some people believe tanning makes them more beautiful, this habit can actually damage their skin in the long run, leading to wrinkles and sagging skin, says a study.”Ultraviolet radiation from the sun and indoor tanning beds not only can increase your risk of skin cancer but also can contribute to skin ageing,” said Arianne Shadi Kourosh from the Massachusetts General Hospital, Boston, US.”Moreover, other forms of radiation, such as heat and visible light, can negatively impact the skin, as can pollution, so protecting your skin from the environment can benefit both your health and appearance,” Kourosh said. Also Read – Add new books to your shelf”Since both types of UV rays – long wave ultraviolet A (UVA) and short wave ultraviolet B (UVB) can damage the skin, it is important to use a broad-spectrum sunscreen that provides both UVA and UVB protection, with an SPF (Sun Protection Factor) of 30 or higher.””Environmental factors can damage the skin in multiple ways, from UVB rays causing sunburns and uneven pigmentation to UVA and infrared radiation penetrating more deeply into the skin to damage existing collagen and reduce collagen production, resulting in wrinkles and sagging skin, added Kourosh.Habitual UV exposure can cause blood vessels to become more prominent, causing skin redness, while visible light and pollution can cause uneven skin tone, especially in darker skin types, researchers said.last_img read more


A colourful story for your home

first_imgSimple, yet creative use of colours can add a fresh vibe to your home, say experts. Here are some tips to consider:Colourful abode: Our home decor can imbibe the cool characters of colours to bring respite from the heat outside. Simple, yet creative use of colours can make your home ready for the summer. Select hues such as pastel green, bright yellow of the Sun or the soft yellows of the freshly blossoming flowers and ripe fruits bringing the brightness of summer – all the natural hues will transform your home into a peaceful sanctuary. The season will be ruled by colours which help lend a natural and refreshing feeling to the home. Adorn your walls or your tapestry with it. Also Read – Add new books to your shelfLet nature do its work: With a wholesome respect for nature, you can bring the outdoors into your home. As nature changes its colours, so can your home. A soft pastel green tone works well. The appealing shades of lavish forests and profound seas offer a rich palette that you can undoubtedly adjust in your home. It is perfect for any nature-lover as it radiates a soothing and peaceful vibe. You can add gold accents in your bedding and pillows to provide a luxurious touch. Also Read – Over 2 hours screen time daily will make your kids impulsiveHues can help you relax: Create the right balance amongst the colours used on the walls. You can use multi-coloured furniture to create that striking contrast with the neutral or pastel shades. For instance, white and beige always rule when it comes to summers given the very cool and calming effect these colours have on the surroundings. Upscale organic: Muted neutrals, from vanilla to browns, a forest green pop, and metallics as an accent, is a combination that translates equally well to a bedroom as it does to the living room. Look out for: Yellow, purple heather, clearly aqua, pink lady and pastel blues are what you might want to look out for. The biggest advantage with delectable ice-cream colours is that it balances out the interiors without making it feel too heavy. Many people are opting for white walls and introducing pastel colours in their room through accent furniture, or artwork.last_img read more


School students visit Traffic Control Room learn nuances

first_imgKolkata: A group of students from Saint Xavier’s Collegiate School, along with few of their teachers, were shown the Traffic Control Room (TCR) at Lalbazar on Saturday and were sensitised about the traffic norms on Saturday.According to sources, on Saturday afternoon, 40 students and few teachers of Saint Xavier’s Collegiate School were taken to the TCR as part of their educational tour. During their visit, they were told about the functions of the Traffic Control Room. A police official was in-charge of briefing the students and teachers. Also Read – Rs 13,000 crore investment to provide 2 lakh jobs: MamataFollowing this, the students learnt about the use of modern technology involved in the management of traffic. They were briefed about how the equipment, such as speed laser gun, speed camera, breath analyzer and others, functioned. Also, they were shown how the traffic signals turned red to green and vice versa. They also interacted with Deputy Commissioner, Traffic, Pandey Santosh. During the interaction, several questions were put across to Santosh. A few of them were about driving licenses and traffic congestion in the city. “Few of the students asked how congestion occurs and how we manage to tackle the situation. They also asked about how a driving license can be obtained and other related questions. They were also shown how our Red Light Violation Detector (RLVD), speed camera and other equipment work. We also had a brief discussion with the teachers about traffic congestion during the rush hours,” said Santosh.last_img read more


Theda Bara – Creator of The Vamp Look and Persona and Early

first_imgTheda Bara can rightfully be called the Godmother of Goth. Starting in the nineteenth century, vampires assailed our imaginations through popular fiction and over the years they became part of our pop culture. Out of the many novels written on the subject, Bram Stoker’s Dracula, published in 1897, is undoubtedly the one that provided the basis for the modern vampire as we all recognize today in films, TV series, and novels. Over the years, Count Dracula has become one of the few fictional characters to appear in over 100 movies. While we all gladly remember legendary actors such as Max Schreck, Bela Lugosi, and of course, Christopher Lee, who masterfully portrayed the famous Count Dracula, the silver-screen “vamp” was created much earlier. To the surprise of many, the epitomé of the “vamp” persona in Hollywood movies was not a caped actor but actually an actress who went by the name of Theda Bara.Cover of “Dracula’s Guest and Other Weird Stories,” a collection of short stories authored by Bram StokerAlthough nowadays Theda Bara is far from a household name, she was actually one of Hollywood’s most popular actresses in the early years of cinema. Her acting career was brief but notable, as she appeared in more than 40 silent movies in a period of just 12 years. Sadly, most of her films were lost, but the 1915 silent film A Fool There Was, in which Theda Bara portrays the Vampire, still exists, and two years ago it was selected for preservation by the United States Library of Congress.Actress Theda Bara in a promotional photoBorn Theodosia Goodman on July 29, 1890, into a family of Jewish immigrants in Cincinnati, Theda Bara dreamed of becoming an actress, and at the age of 18, she went to New York City, hoping to make her dream a reality.Theda Bara, in a scene from “Salomé.”She struggled at the beginning with little success, but her luck changed in 1915, when director Frank Powell cast her for the role of the seductive Vampire in A Fool There Was. The film would turn her world upside-down, making her an overnight sensation and the first Hollywood “vamp,” as it was this nickname for Bara’s character that coined the term.Movie PosterFans loved the new exotic–and erotic–actress; in fact, they loved her so much that she allegedly received over 1,000 marriage proposals. Countless songs have been written about her and many children were named Theda in her honor. As written by the Guardian‘s Kira Cochrane, there was also “a perfume and even a sandwich (minced ham, mayonnaise, sliced pimento and sweet pickles on toast served warm) created in her honor.” Theda Bara in “A Fool There Was”Part of her success story is the incredible marketing strategy created by the Fox studio, which includes her fabricated screen name, Theda Bara, rather mysterious origins, and vampirish personality. According to the studio, she wasn’t born in Cincinnati, Ohio, nor into a family of Jewish immigrants, but to a French actress and an Italian sculptor. The public apparently bought the story and success was inevitable for the then 29-year-old actress.“Cleopatra” (1917)During the next few years, she went on to star in more than 40 movies, adding details to her vamp image. She became far more than just Hollywood’s first “vamp” and is now considered by many to be the first true sex symbol in the history of Hollywood.“The Soul of Buddha” (1918)However, her reign as queen of the vamps was sadly short-lived as her contract was dropped by Fox in 1919, meaning that her acting career was virtually over. Vamps were no longer in vogue, and Hollywood was now hunting innocent faces such as Mary Pickford and Marguerite Clark, which meant that Theda Bara was out of the game.“A Woman There Was” (1919)She made several attempts to resurrect her Hollywood career but ended up parodying the vamp image she worked so hard to create. In 1921, Bara married director-writer Charles Brabin, with whom she spent the rest of her life.Read another story from us: The first Hollywood male sex symbol was Japanese actor Sessue HayakawaAfter 1926, she no longer made attempts to regain her star status, and she never appeared in a sound film. The queen of the vamps left this world on April 7, 1955, dying in Los Angeles at the age of 69.last_img read more