Physicists use quantum memory to demonstrate quantum secure direct communication

first_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. Experimental set-up of quantum secure direct communication with quantum memory. Credit: Zhang et al. ©2017 American Physical Society The researchers, Wei Zhang et al., from the University of Science and Technology of China and Nanjing University of Posts and Telecommunications, have published a paper on their experimental demonstration in a recent issue of Physical Review Letters.QSDC is one of several different types of quantum communication methods, and has the ability to directly transmit secret messages over a quantum channel. Unlike most other quantum communication methods, QSDC does not require that the two parties communicating share a private key in advance. Similar to other kinds of quantum communication, the security of the method relies on some of the basic principles of quantum mechanics, such as the uncertainty principle and the no-cloning theorem.As the physicists explain, a quantum memory is necessary for QSDC protocols in order to effectively control the transfer of information in future quantum networks. However, experimentally realizing quantum memory with QSDC is challenging because it requires storing entangled single photons and establishing the entanglement between separated memories.In their experiments, the researchers demonstrated most of the essential steps of the protocol, including entanglement generation; channel security; and the distribution, storage, and encoding of entangled photons. Due to the difficulty of decoding entangled photons in the optimal way (which requires distinguishing between four quantum states), the researchers used an alternative decoding method that is easier to implement.In the future, the researchers expect that it will be possible to demonstrate QSDC across distances of 100 km or more in free space, similar to the recent demonstrations of quantum key distribution, quantum teleportation and entanglement distribution over these distances. Achieving this goal will mark an important step in realizing satellite-based long-distance and global-scale QSDC in the future. Explore further Physicists add amplifier to quantum communication toolbox More information: Wei Zhang et al. “Quantum Secure Direct Communication with Quantum Memory.” Physical Review Letters. DOI: 10.1103/PhysRevLett.118.220501Also at arXiv:1609.09184 [quant-ph]center_img © 2017 Phys.org For the first time, physicists have experimentally demonstrated a quantum secure direct communication (QSDC) protocol combined with quantum memory, which is essential for storing and controlling the transfer of information. Until now, QSDC protocols have used fiber delay lines as a substitute for quantum memory, but the use of quantum memory is necessary for future applications, such as long-distance communication over secure quantum networks. Citation: Physicists use quantum memory to demonstrate quantum secure direct communication (2017, June 12) retrieved 18 August 2019 from https://phys.org/news/2017-06-physicists-quantum-memory.html Journal information: Physical Review Letterslast_img read more

New study suggests some ancient bite marks from crocs not stone tools

first_img © 2017 Phys.org In recent years, several teams of archaeologists have made claims regarding the earliest use of tools by hominids, some going back as far as 4 million years. These new studies have used evidence of marks on animal bones as proof of tool use, rather than actually finding stone tool artifacts. In this new effort, the research trio suggests that marks on bones do not appear to offer strong enough evidence of tool use.For many years, scientists in the field have believed that when animals make marks on bones, the results are U-shaped, whereas those made by stone tools are V-shaped. But that, the researchers point out, was based on studies of hyenas. In running their own tests, they compared crocodile bite marks to stone tool marks and found them very nearly identical. More information: Yonatan Sahle et al. Hominid butchers and biting crocodiles in the African Plio–Pleistocene, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1716317114AbstractZooarchaeologists have long relied on linear traces and pits found on the surfaces of ancient bones to infer ancient hominid behaviors such as slicing, chopping, and percussive actions during butchery of mammal carcasses. However, such claims about Plio–Pleistocene hominids rely mostly on very small assemblages of bony remains. Furthermore, recent experiments on trampling animals and biting crocodiles have shown each to be capable of producing mimics of such marks. This equifinality—the creation of similar products by different processes—makes deciphering early archaeological bone assemblages difficult. Bone modifications among Ethiopian Plio–Pleistocene hominid and faunal remains at Asa Issie, Maka, Hadar, and Bouri were reassessed in light of these findings. The results show that crocodiles were important modifiers of these bone assemblages. The relative roles of hominids, mammalian carnivores, and crocodiles in the formation of Oldowan zooarchaeological assemblages will only be accurately revealed by better bounding equifinality. Critical analysis within a consilience-based approach is identified as the pathway forward. More experimental studies and increased archaeological fieldwork aimed at generating adequate samples are now required. Linear marks and pits on a 2.5 million-year-old ungulate leg bone from Bouri, Ethiopia. Credit: PNAS To learn more about stone tool markings, the researchers used actual stone tools to butcher some sheep. To learn more about crocodile markings, they studied work done by Jackson Njau, who, in 2006, documented bite marks made on animal bones by crocodiles living on an animal farm. When they compared the marks they had made on the bones with those shown by Njau, they found them to be virtually indistinguishable, even at the microscopic level. This, the trio suggests, indicates that using bite marks found on ancient bones as evidence of stone tool use is premature. They believe the marks could just as easily come from crocodiles, which, they note, lived in the areas where the ancient bones were found. Citation: New study suggests some ancient bite marks from crocs not stone tools (2017, November 7) retrieved 18 August 2019 from https://phys.org/news/2017-11-ancient-crocs-stone-tools.html Explore further Analytical standards needed for ‘reading’ Pliocene bones Linear marks and pits on a 2.5 million-year-old ungulate leg bone from Bouri, Ethiopia. Credit: PNAS 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. Journal information: Proceedings of the National Academy of Sciences (Phys.org)—A trio of researchers, two with the University of Tübingen in Germany, the other the University of California has found evidence that suggests it is not possible to tell if marks on some ancient artifacts were made by ancient hominids using stone tools or by crocodiles. In their paper published in Proceedings of the National Academy of Sciences, Yonatan Sahle, Sireen El Zaatari and Tim White describe their study comparing bite marks made by stone tools and crocodiles, what they found by doing so, and what it might mean for research results made by other teams. Linear marks and pits on a 2.5 million-year-old ungulate leg bone from Bouri, Ethiopia. Credit: PNASlast_img read more

Nanogenerators 2500 stretchability sets new record

first_img Journal information: Nature Communications Stretchable nanogenerator. Credit: Parida et al. Published in Nature Communications © 2019 Science X Network More information: Kaushik Parida et al. “Extremely stretchable and self-healing conductor based on thermoplastic elastomer for all-three-dimensional printed triboelectric nanogenerator.” Nature Communications, volume 10, Article number: 2158 (2019) 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. Explore furthercenter_img Chinese team develops skin-like triboelectric nanogenerator The researchers, including Kaushik Parida, Gurunathan Thangavel, and Pooi See Lee at Nanyang Technology University and the Singapore-HUJ Alliance for Research and Enterprise (SHARE), have published their results on the highly stretchable, all-3D-printed triboelectric nanogenerator in a recent issue of Nature Communications. Triboelectric nanogenerators (TENGs) harvest energy from ambient mechanical movements, such as finger tapping, and have potential applications as wearable electronic devices. Making TENGs stretchable is difficult because the two main layers—the triboelectric layer and the conductor—usually have different elastic properties, so they tend to come apart after repeated stretching. To address this issue, in the new study the researchers used the same elastic material (polyurethane acrylate, or PUA) as the basis for both the triboelectric layer and the polymer matrix for the conductor. To increase the conductivity, the researchers also added liquid metal particles and silver flakes to the conductor. When the nanogenerator undergoes extreme stretching, the hydrogen bonds in the PUA reversibly break and reform to support the desired stretchability. At the same time, the liquid metal particle shells break and release conductive liquid metal to provide a connection between the separated silver flakes in the PUA matrix, allowing the device to maintain a high conductivity.The researchers also demonstrated that the nanogenerator can be cut apart into separate pieces, and yet still almost completely regain its original performance after a healing process consisting of 24 hours of heating. The nanogenerator is also the first in which all components were printed using a 3D printer. Previously, only the triboelectric layer has been 3D-printed, since most elastomeric materials have limited stretchability when fabricated with 3D printing. With its high stretchability and conductivity, as well as the ease of fabrication with 3D printing, the nanogenerator has potential applications as an energy harvester for small portable self-powered electronics, including LEDs and sensors. Citation: Nanogenerator’s 2500% stretchability sets new record (2019, June 24) retrieved 18 August 2019 from https://phys.org/news/2019-06-nanogenerator-stretchability.html By stretching like a rubber band to more than 25 times its original length, a new nanogenerator has set a new stretchability record. The triboelectric nanogenerator’s 2500% stretchability represents a significant increase over the previous best values of approximately 1000%. In addition, the device is the first triboelectric nanogenerator that is completely fabricated with 3D printing.last_img read more

The legend of Krishna

first_imgThe play Krishna staged at Kamani Auditorium during Shriram Bharatiya Kala Kendra’s annual cultural performances leaves the audience spell bound and inspired.Lord Krishna, the one with many avatars, sometimes he is looked upon as the mischevious son of Yashoda, at times love of Radha, lord of Meera and usually as the lord of wisdom imparting knowledge to Arjun on the battlefields of Kurukshetra.His legend has enthralled humanity for over three thousand years and carries with it pearls of wisdom, that enjoy as much ancient, traditional relevance as a contemporary context and in that sense retain a timeless appeal for as long as humans and their emotions exist. All these avatars of Krishna came alive on stage on stage at the Kamani Auditorium during Shriram Bharatiya Kala Kendra’s 36 edition of annual cultural performances, Krishna. Also Read – ‘Playing Jojo was emotionally exhausting’The thoroughly researched production presents the adorable maakhan chor and beloved of Radha on one hand and on the other, the invincible omnipotent Krishna, who commands with wisdom, dignity and infallible strength the flow of events in history. This drama narration directed by Shobha Singh beautifully depicts the journey of Krishna from early childhood’s youthful antics, to the centre stage of human reverence.On one side, the part of the narration where Krishna is portrayed as the notorious son made the audience dwell on the image while later when he enunciates the wisdom of the revered Bhagwad Gita, delivering practical solutions rather than pursuing blind faith dictating right and wrong inspires the audience.All facets of Krishna’s persona are treated with creative sensitivity, lending a mesmeric dynamism to the production. The showcase of violence and eventual emergence of harmony, despite all odds emerges hope for eventual peace, despite apparent chaos in the present.last_img read more

Time to turn devotional

first_imgA three- day Bhakti Sangeet festival is being organised by Delhi Government to renew the message of unconditional love. The festival that opened yesterday (9 May) will be featuring 14 devotional singers of different genres. For people who love devotional music, this festival serves as a platform to look up to. The festival brings together a wide range of devotional singers who perform bhakti music in their own different cultural forms – be it through bhajans, vedic chanting, baul singing, or qawwali and sufiana kalams. Among the singers who will be participating in the festival are Hans Raj Hans, Shubha Mudgal, Mohammad Irshad and Aslam Sabri. Also Read – ‘Playing Jojo was emotionally exhausting’The opening day of the festival was attended by S K Srivastava, Chief Secretary, Government of Delhi as Chief Guest along with Rinku Dugga, Secretary, Department of Art, Culture and Languages, Govt of Delhi.Starting with a session of Rigveda chanting by K Vasedevan Namboothiri, A M Kesavan and K Madhavan Namboothiri, the event features the baul singing of Bengal by Parvathi Baul, Punjabi Sufi kalam by Hans Raj Hans, Sagun and Abhang bhakti traditions by Sanjeev Abhayankar, and the kalam of Bulle Shah by Mohammad Irshad over three days. Also Read – Leslie doing new comedy special with Netflix’Music is an eternal natural component of human life. Even a baby who doesn’t speak responds to music beats. When you use this medium to express your unconditional love to your creator, the result can easily stir any soul. We are a nation of spirituality and we have multifarious ways of professing our love to God. Bhakti Sangeet is unique as it brings together all different genres of devotional music prevalent in India on one stage,’ says Prahlad Singh Tipania, folk singer from Madhya Pradesh who performs Kabir bhajans in the state’s Malwi folk style. On 10 May the festival will feature Buddhist Chanting (Bhutan), krishna bhakti by  O. S. Arun and Kalaam Bulle Shah by Mohammad Irshad. The closing day (11 May) will feature Shubha Mudgal singing Nirgun bhakti, Prahlad Singh Tipania with his Kabir bhakti in Malwi folf traditions and Agnihotri Bandhu rendering Ram and Hanuman bhakti.In different regions and different cultures, people develop and nurture their own bhakti and sufi traditions. The festival brings together many such different genres of bhakti from different parts of the country. It was our bhakti and sufi saints who originally laid the foundation of our composite culture and this festival is an ode to them. Where: Nehru Park, Chankya Puri, When: On till 11 MayTiming: 6.30 pm onwardslast_img read more

Cultural heritage Oh right up our alley

first_imgWhen it comes to conserving historical sites and heritage and making sure culture is preserved, India is right up there in the list of countries who knows what to do and how to do it! And United Nations acknowledges it as well and that too a second time in a row!India has been elected for the next four years to the UN body for safeguarding of the intangible cultural heritage of nations, groups and individuals.In a vote this morning at UNESCO headquarters by the General Assembly of the States Party to the Convention for the Safeguarding of the Intangible Cultural Heritage, India won the election by a resounding 135 votes out a total of 142 votes cast by member states who were present and voting, said an external affairs ministry statement recently.  Also Read – ‘Playing Jojo was emotionally exhausting’The Intergovernmental Committee for the Safeguarding of the Intangible Cultural Heritage has 24 members who are elected for a term of four years.The core functions of the committee are to safeguard the intangible cultural heritage (ICH), ensure respect for the intangible cultural heritage of nations, groups and individuals, as also to raise awareness at the local, national and international levels of the importance of the intangible cultural heritage.This is the second time that India has been elected to the Intergovernmental Committee for the Safeguarding of the Intangible Cultural Heritage, the earlier term being from 2006-2010 and as the news goes, big plans are on the cards.last_img read more

Turkish delight

first_imgThe Turkish Embassy celebrated the Turkish National day with great splendor at the Embassy of the Republic of Turkey Residence on Prithviraj Road in the Capital. Navtej Singh Sarna, Secretary (West), Ministry of External Affairs was the distinguished Chief Guest for the evening. Several diplomats and dignitaries and social influencers attended the  event. A vibrant folk dance performance by the Giresun University Turkish Folk Dance Troupe from Turkey commenced the evening. The dance troupe, presented a very colorful and pulsating show of Turkish folk dances, with authentic costumes and traditional instruments like Kemanche and Tulum and portrayed the nature of the Black Sea region while depicting a love story. However, the showstopper of the evening was a solo performance titled ‘Zeybek Dance’ by Mr. Gökhan Barutçu, the leader of the troupe and the traditional dance show named ‘Horon’, characterized by tense and quick movements which represent the cheerful and dynamic people of the Black Sea Region. Also Read – ‘Playing Jojo was emotionally exhausting’Famous Turkish model Gulcin Karakus was also spotted at the celebrations. Karakus was crowned Miss Galaxy 2010 in Germany and Miss Turkey Tourism Queen of the Year International 2010 in  China, followed by the title of  Miss Freedom Of The World in 2011. To celebrate the Republic Day of Turkey, a master chef and a chef from the State Guest House of Turkey in Ankara were especially flown down and they dished out delicious Turkish delicacies. The event was a huge success with everyone taking back a little part of Turkey. The event took place on 29 October.last_img read more

One held for smuggling banned substances into correctional home

first_imgKolkata: The Alipore police station on Saturday night arrested a person on charges of smuggling mobile phones, narcotics, alcohol and razor blades into Alipore Central Correctional Home.The person named Mohammad Mosharaf was arrested on the basis of a tip off from Baruipur in South 24-Parganas.The name of Mosharaf had cropped up during the interrogation of Amitava Chowdhary – a medical professional attached to the prison, who was caught red-handed on the night of June 8. The sleuths had recovered four kg of marijuana, huge amount of alcohol, 35 cellphones, chargers and Rs 1.46 lakh in cash from his possession. “We have learnt that it was Mosharaf, who used to supply majority of these items to Chowdhary,” a senior police officer said. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedState Correctional Administration minister Ujjal Biswas said: “We are keeping a close watch to curb the practice of smuggling things into correctional homes. There are more people involved and we will unearth the entire racket.”Four mobile phones were also recovered from the prison premises on Sunday morning. “We are trying to find out how these phones were sneaked in inspite of tight vigil,” a senior official said.The state Correctional Administration department has decided to impose fines on the inmates if they are found using cell phones inside the prison premises. The decision of the department comes in the wake of allegations regarding the use of cell phones by prisoners in a number of correctional homes across the state. Also Read – Naihati: 10 councillors return to TMC from BJP”We have prepared a draft suggesting amendment in the West Bengal Correctional Services Act 1992 with the inclusion of this aspect of fine. It has already been sent to the Law department. We hope to pass the amendment in this regard in the monsoon session of the state Assembly,” a senior official said.It is learnt that the department has recommended to impose a fine of Rs 10,000 on inmates caught using cell phones inside the prison.last_img read more

Tourism dept looks to boost Durga Puja carnivals appeal

first_imgKolkata: The state Tourism department has decided to give a boost to the Durga Puja carnival at Red Road this year, by taking the foreign tourists to visit different places in Bengal, before or after the day of the carnival.”Last year, we found that a good number of foreign tourists had come to Bengal to witness the Durga Puja carnival at Red Road. We want to showcase the beauty of Bengal to these tourists by taking them to explore different places before or after the event. So, we will be coming up with some attractive packages to woo the foreigners,” said Atri Bhattacharya, state Principal Secretary, Tourism, at the inauguration of the three-day Travel and Tourism Fair (TTF) at Netaji Indoor stadium on Friday. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe state government is also trying its best to boost home stay tourism in the state. A number of homestays across the state have already been linked with the website of West Bengal Tourism Development Corporation and online bookings can be made through the website.Bangladesh Tourism minister Shahjahan Kamal, whowas also present at the inaugural programme, said bothIndia and his country have taken steps to ensure easy and hurdle-free travel for the tourists. Also Read – Naihati: 10 councillors return to TMC from BJP”The two countries have taken measures to increase connectivity through roads, rail and air, facilitating tourists from India to visit Bangladesh easily,” he said.According to the minister, Bangladesh is not only a “culturally rich” country and a land of natural beauty, but also boasts of the world’s largest unbroken beach at Coxbazar.There are nine daily flights that operate between the two countries daily, apart from train services connecting Kolkata with Dhaka and Khulna. Nepal Consul General in Kolkata Ek Narayan Aryal said the three neighbours can sew up a tourist circuit.”India, Nepal and Bangladesh are very close neighbours. We can create a tourist circuit to reach out to people of the three countries,” Aryal maintained.Altogether 13 countries and 28 Indian states are participating in the tourism fair, which is in its 30th year, said Sanjiv Agarwal, the CEO of Fairfest – the organiser of the event.last_img read more

TMC practices syndicate of the people says Abhishek

first_imgKolkata: Abhishek Banerjee, Trinamool Congress MP and president of the party’s youth wing, has urged people to help Trinamool Congress candidates win all the 42 Lok Sabha seats in Bengal and ensure that the BJP does not get a single seat.Addressing a counter-rally at Midnapore College Grounds where Prime Minister Narendra Modi had addressed a meeting on July 16, Banerjee said: “Our supremo Mamata Banerjee had set a target for the party to defeat the BJP in 2019 Lok Sabha election at the Martyr’s Day programme held on July 21. She had said we have to win all the 42 seats in the state and oust the saffron party from the Centre in 2019.” Also Read – Rain batters Kolkata, cripples normal life”They (BJP) had claimed that they would win 22 seats. We have to ensure that they do not even win that much seats in the state. Let us take a pledge to oust the BJP from Delhi in 2019 and establish a government that will ensure communal harmony, benefit of the farmers and advancement of health and education,” he added.Taking a dig at the Prime Minister, who had alleged that the ruling Trinamool Congress runs a syndicate raj in the state, Banerjee stated: “I admit that the Trinamool Congress is running a syndicate. It has been practicing the “syndicate of the people” that ended 34 years of Left Front Rule in the state in 2011, established peace in Maoist-affected Junglemahal and restored tranquility in Darjeeling hills by breaking the unholy nexus of Bimal Gurung and Roshan Giri. We are forming a new people’s syndicate in the days to come to topple the BJP government Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedfrom power”.Banerjee also reiterated that Modi had done very little for the Hindus in the country. Accusing the BJP of creating a rift between the Hindus and the Muslims, he said: “We will not let that happen”.He also mentioned that the PM had taken up a project of cleaning River Ganga (Namami Gange) and allocated a budget of Rs 3,000 crore but not even a pond was cleaned.He further alleged that the BJP had brought people from four neighbouring states and 10 neighbouring districts for the Prime Minister’s rally. “There were vehicles from states like Jharkhand, Bihar, Uttar Pradesh and Odisha, while it was difficult to spot even a single farmer, despite calling it as a farmer’s welfare meeting,” he maintained. He dared the Prime Minister to organise a similar programme in states like Maharashtra and Madhya Pradesh that had witnessed a number of farmer suicides.Apart from Banerjee, senior TMC leaders like Partha Chatterjee, Suvendu Adhikari, Firhad Hakim, Subrata Bakshi also claimed that the TMC would win all the 42 seats in the state and the BJP would not be able to win a single seat.last_img read more