What we learned at Raiders HQ Thursday

first_imgALAMEDA — Derek Carr knows the feeling of desperation.As a surprise rookie starter at quarterback, the Raiders were 0-10 with Carr at the helm after falling 13-6 to the San Diego Chargers on Nov. 16, 2014.Dennis Allen was fired as head coach after an 0-4 start, interim coach Tony Sparano buried a football at the practice facility to represent burying the old ways, and the losing continued.So when the 0-9 Cincinnati Bengals visit the Coliseum Sunday at 1:25 p.m., Carr has a pretty good idea …last_img

Water Theories Evaporate

first_img(Visited 123 times, 1 visits today)FacebookTwitterPinterestSave分享0 After decades of telling the public comets brought Earth’s water, scientists are giving up on the idea. It was volcanoes, now they say.A geologist and mineralogist from Trinity College Dublin says that “Scientists are changing their minds about how the Earth’s water got here.” Writing on The Conversation, Balz Kamber points to evidences that go against the special-delivery theory (what we have called the “water balloon theory”, 7/23/12) for the origin of Earth’s water.The isotope of ruthenium found on Earth’s surface is the wrong type to have come from the outer solar system. Ruthenium, a siderophile (iron-loving) element, should have been dragged with iron into Earth’s core. This suggested to geophysicists in the 1970s that it was delivered by comets and asteroids in a “late veneer” after the Earth differentiated, leaving water on the surface as a by-product. But if the impactors were from the inner solar system, they would have been too dry.Zircons, thought to have been formed 4.3 billion years ago, appear to have been in contact with water some 200- to 400-million Darwin Years before the “late veneer” should have formed.The heat of impacts may have obliterated water as much as delivered it.The presence of chlorine implies that it had water to dissolve into – otherwise it would have been lost to space.If water was on Earth early on, it must have already been here at the time of formation. How could that be on a molten world rife with volcanoes? According to Kamber, volcanoes were the answer. They spewed up minerals that contained hydroxyl ions (OH–) which recombined into H2O as the minerals crystallized. Cute theory; does it work?But it is important to understand that water can also be recycled back into the mantle. This means there is a balance between the water in the oceans and that stored up in the mantle. We can only speculate how much water might still be locked up at these great depths.What we do know is that the average level of the sea surface relative to the continental land has remained relatively constant across nearly four billion years. This suggests a constant cycle of water emerging from and being absorbed back into the mantle has significantly helped life to continue throughout its history on this planet.How, though, would the current levels be established? If the rates are balanced, any water erupted would have sunk back into the mantle just as quickly. Is he sure that volatiles will collect on the surface instead of being lost to space, before an ozone layer protected the surface from ultraviolet rays? Why don’t we see oceans forming around volcanoes today? Kamber seems to invoke special pleading to come up with a 70% watery surface that has “significantly helped life” since its inception. Does this improve on luck or miracles?A bigger issue is the demise of a theory after over 40 years of propaganda. Learning that lesson, what confidence can anyone have that the inside-out theory will survive the next 40 years?Not all water is just water. It has properties, such as acidity. The deuterium ratio, not mentioned by Kamber, was another blow to the water-balloon theory. A paper in Science discusses “The geologic history of seawater pH.” Here’s the editors’ summary:The acid-base balance of the oceans has been critical in maintaining Earth’s habitability and allowing the emergence of early life. Despite this importance, systematic estimates of historical seawater pH are lacking. Halevy and Bachan developed a model of seawater chemistry and pH over time scales exceeding ∼100 million years. Their highly robust probabilistic history of seawater pH and chemistry reflects evolving properties of Earth’s atmosphere, oceans, and crust. Seawater pH increased from early Archean values of ∼6.5 to 7.0 to more recent values of ∼7.5 to 9.0 mostly as a result of solar brightening and decreasing interaction between seawater and oceanic crust.What they mean is that the model is robust within its own assumptions, not that it connects with the real world. There’s no way they could know such things. All they know is that there is a constraint that the water’s acidity be survivable over the history of life on Earth from the beginning, “allowing the emergence of early life.” Note to the authors: emergence is a miracle word (see Poof Spoof), and pH constrains life— it doesn’t “allow” it. Otherwise it’s like saying that the existence of air “allows” birds to emerge and fly.Secular materialists have been oscillating between the water-balloon theory and the volcano theory for decades, for centuries, since Laplace famously said he had no need of that [God] hypothesis. Well, are they making progress? They’re like witless gamers shuffling cups around on the table trying to figure out which one has the marble under it. They lift a cup once in awhile, find out there’s no marble, and think, “It must be under the other one.” Shuffle some more; try again. This goes on for centuries. How about the hypothesis that there is no marble – i.e., there is no secular theory that works?What’s clear from these two papers is that life requires water from the beginning. Strange; that’s what the Bible says happened.last_img read more

Urban organic agriculture in downtown Joburg

first_imgTurning upmarket bowling greens into food gardens … Volunteers at work tilling the soil to plant organic fruit and vegetables for the Bambanani Food and Herb Garden in Bertrams.Working on the food garden helps build a sense of community among the people living in Bertrams. Many of them, people who have moved to Johannesburg from rural areas, have the skills and knowledge to work the land.(Images: Bambanani Food and Herb Garden)MEDIA CONTACTS• Amon Maluleke076 873 9886• Maria Maseko082 464 9507Bambanani Food and Herb GardenRELATED ARTICLES• AgriHUB helps small-scale KwaZulu-Natal farmers• Africa can produce the food it needs• Kilimo Salama farmers’ safety • Rewarding efforts to save the planet • Farming in the heart of Joburg Discussions about the regeneration of Johannesburg’s inner city usually revolve around refurbishment of buildings and attracting business and residents into the city. But an award-winning project in downtown Johannesburg with the ambitious long-term aim of feeding poor people in the inner city is changing the conversation.Urban farming has taken root in the run-down suburb of Betrams, as part of a municipal programme to revitalise the city. The Bambanani Food and Herb Garden has reclaimed the abandoned bowling greens of the old Bertrams Bowling Club, once a recreation centre reserved for white people during the apartheid era. Now, the lawns have been turned over, furrows tilled, soil fertilised, and vegetables planted and harvested.Earlier in November 2013 the project won the Mma Tshepo Khumbane Award, from the Gauteng Department of Agriculture and Rural Development, for the best community-based natural resources management project in the province. Khumbane is a grassroots activist and the founder of the Water for Food Movement, which works in rural Gauteng. For 40 years she has tried to fight malnutrition and hunger by encouraging small-scale farming.‘No need to go hungry’The brim of Maria Maseko’s hat shades her eyes from the afternoon sun: it’s cloudless summer day with temperatures pushing into the 30s. One of the original volunteers at the Bambanani project, she takes in the familiar view of the dramatic Johannesburg skyline, with the iconic concrete tube of the Ponte Tower, and Ellis Park Stadium. “There is no need for anyone to ever go to bed hungry in Betrams, not when there is access to healthy affordable food right on their doorstep,” she says.Bambanani is just one of a number of art, sport and agriculture projects in downtown Johannesburg that are changing the way Joburgers experience their city. The garden is part of what is called Hope Village, a redevelopment project that includes a cricket oval and recreation centre for the kids of Bertrams and Hillbrow.Started with a R21 000 grant from the city in 2006 for seed and tools and the efforts of a group of 10 volunteers, the garden supplies cheap organic vegetables to the local community, and sells to street hawkers and the Bertrams Spar supermarket. The generosity of sponsors such as Talborne Organics and Jojo Tanks and the passion of people like Maseko and fellow volunteer Amon Maluleke has kept the project growing.Food and memory“We dug up the lawn and planted our first crop by hand,” says Maseko, who recently retired from Johannesburg’s Department of Social Development. “It was hard, backbreaking work but it’s a crucial part of the creation of a diverse ecosystem and an important bonding tool for the local community.”The gardeners use the companion planting method and their harvests are Participatory Guarantee Systems certified as organic. This allows the cooperative to also sell their products at local organic markets.“We grow our tomatoes next to our basil. This gives the tomatoes a rich taste, but more importantly the basil protects the plants from insects,” Maseko explains. She pulls a head of kale, known as shiyama to most Africans, out of the ground. It is a deep green and fills both her palms. It sells at the garden for R15 a head; at a supermarket it’s R30.As the suburb declined over the years, the Bertrams Bowling Club, the site of the garden, fell into disuse. The City of Johannesburg decided its two bowling greens would be better used to grow vegetables. The gardeners now produce an astonishing variety of vegetables, potatoes, sweet potatoes, cabbage, chillies, spinach, kale, onions and butternut. The once-fallow plot is now a bright green space, filled with activity and colour.“This Congolese man brought us seeds indigenous to the Congo,” Maseko says. “He wanted us to plant them so he could he have a taste of home here. Those are the memories food can evoke.”‘They know how to work the land’Bertrams, and Johannesburg, offers a collection of stunning architecture and museums but to a transplant like Amon Maluleke, from rural Limpopo, the city lacked green space that would allow people with the skills to farm vegetables. “People come to the city and want to work in a job where they wear a tie but they don’t have the skills,” he says. “Like me they know how to work the land, they can feed themselves, they can feed their neighbours if they were given the space and the opportunity.”Maluleke came upon the inner city farm in July 2007 after he had been retrenched. He is now assistant groundskeeper at the adjacent cricket oval, home to the Johannesburg Cricket Club, and is studying towards a degree in ornamental horticulture.Bambanani also serves as a gardening academy, training nursery school staff from across the city in the art of vegetable gardening. Across Bertrams school grounds that would have been planted with flowers are now being turned into fertile corners bursting with freshly grown fruit and vegetables. These are, in part, driven by need, but spurred on by the efforts of the volunteers at Bambanani.“In the beginning the idea behind Bambanani was regeneration of the neighbourhood and to improve the health of its residents by making fresh organic fruit and vegetables available to them,” says Maluleke. “It’s taken hold of people’s imaginations. They see the importance of fresh, healthy food and the need for green, working space in the city.”Garden suburb, then and nowOriginally built as a suburb for the professional classes, Bertrams abuts Old Doornfontein, the preferred neighbourhood for the city’s wealthy entrepreneurial classes in the early days of Johannesburg. Today it’s a suburb in transition with a multicultural population of South Africans and African refugees building a vibrant community of small businesses and sports clubs.Bertrams can lay claim to some famous past residents. Robert Baden Powell, the founder of the Boy Scouts, and colonial magnate Cecil John Rhodes lived on the ridge that today overlooks Ellis Park Stadium. Infamous serial poisoner Daisy de Melker did her misdeeds in the suburb. When it was incorporated into the city in 1897 Bertrams was known for its gardens and stables housing thoroughbred horses. Today it’s a part of the city most people race through with car windows closed and doors locked.What they miss as they speed through the neighbourhood is how the area is becoming a place of fecundity again. On the surface it seems to be on the brink of ecological and social collapse, but if you look closely you will see the green shoots of abundance.last_img read more

‘Amazing’ Nadal better than ever, says Wawrinka

first_imgRead Next “For sure he’s playing the best he’s ever played. That’s for sure. But not only here,” said Wawrinka, who lost for the first time in four Grand Slam finals.“I think since the beginning of the year, you can see he’s playing more aggressive, staying more close from the line.FEATURED STORIESSPORTSSEA Games: Biñan football stadium stands out in preparedness, completionSPORTSPrivate companies step in to help SEA Games hostingSPORTSMalditas save PH from shutout“But that’s clearly his best he ever play. That’s why he’s winning so much again.”Wawrinka admitted the daunting mental challenge of facing Nadal on his favorite surface contributed heavily to the crushing defeat. Lacson: SEA Games fund put in foundation like ‘Napoles case’ MOST READ TNT draws first blood Heart Evangelista admits she’s pregnant… with chicken World’s 50 Best Restaurants launches new drinking and dining guide Cayetano dares Lacson, Drilon to take lie-detector test: Wala akong kinita sa SEA Games Don’t miss out on the latest news and information. WATCH: Firefighters rescue baby seal found in parking garage But the 32-year-old, the oldest Roland Garros finalist in 44 years, had no answers as Nadal eclipsed Pete Sampras on the all-time list of major champions with 15 titles.“He’s an amazing fighter. On clay he’s just tough to play. There is always one ball coming back. He creates doubts that you cannot have if you want to beat him.“I think today, if you play Rafa, if you’re not completely free with what you think and what you’re gonna do and not completely relaxed the way you’re gonna play, you have no chance.”Nadal won for the 16th time in 19 meetings with Wawrinka, who insisted there was plenty to be positive about following his recent performances.“In three weeks I won Geneva and made final of a Grand Slam, so that’s big for me,” said Wawrinka, who will rise a spot to third in the rankings.“But I will need few days to really see that, because it’s tough to describe the feeling of losing a Grand Slam final.” CBBSports Related Videospowered by AdSparc Switzerland’s Stan Wawrinka (left) bows to Rafael Nadal (right) in the final of the 10th French Open on June 11, 2017, conceding that the Frenchman  is back at his peak form. APPARIS, France — Stan Wawrinka said Rafael Nadal was back at the peak of his powers after storming to an incredible 10th French Open title on Sunday.Swiss third seed Wawrinka was trying to win his second Roland Garros title in three years but was blown away by Nadal 6-2, 6-3, 6-1.ADVERTISEMENT What ‘missteps’? “He’s playing his best level on clay. Five-set match, you know, it’s going to be a really tough challenge when you play against him,” said the Swiss.“I didn’t play my best tennis for sure, I was a little bit hesitant with my selection of shots.“When you play against Rafa, if you hesitate, it’s no good. If you hesitate for half a second, it’s too late. You will be late.“Physically I felt good, but mentally it was tough.”Wawrinka arrived in Paris fresh off winning a clay court title in Geneva and knocked out world number one Andy Murray in a five-set thriller in the semi-finals.ADVERTISEMENT 1 dead in Cavite blast, fire Heart Evangelista admits she’s pregnant… with chicken Robredo: True leaders perform well despite having ‘uninspiring’ boss PLAY LIST 02:49Robredo: True leaders perform well despite having ‘uninspiring’ boss02:42PH underwater hockey team aims to make waves in SEA Games01:44Philippines marks anniversary of massacre with calls for justice01:19Fire erupts in Barangay Tatalon in Quezon City01:07Trump talks impeachment while meeting NCAA athletes02:49World-class track facilities installed at NCC for SEA Games LATEST STORIES View commentslast_img read more

Emancipation Day 2017 Message by Leader of the Opposition, Dr. Peter Phillips

first_img Let me wish for you all a restful, happy and safe Emancipation Day. May God continue to bless you and bless our country – Jamaica, land we love. My fellow Jamaicans:I greet you in the spirit of the freedom that we now celebrate annually on Emancipation Day.This celebration is a timely reminder of the struggles waged by our forebears against plantation slavery for over two centuries.Freedom is a fundamental right of human existence and is also the essential first step in the march of any people to nationhood.Two of the greatest leaders in the struggles of our people to free themselves from the shackles of plantation slavery were Nanny of the Maroons and Sam Sharpe.It was in recognition of their roles as both architects and symbols “of our transformation from slavery to freedom” that both were made National Heroes.Jamaica’s long march to nationhood began with Emancipation which laid the basis for our national identity and taught us to appreciate our rich cultural heritage.It is on the foundation of Emancipation that Jamaicans built the national movement and claimed their right to the freedoms we enjoy today to live in dignity, work in harmony, and to secure a better economic future for ourselves and our families.The celebration of Emancipation Day shouldbe recognized as the bedrock on which ordinary Jamaicans with extra-ordinary bravery and vision forced the refashioning of our nation’s cultural, social, economic and political arrangements.Today, the examples of our freedom fighters must inspire us to assert our rights to live in a Jamaica that provides social justice and equality of opportunity, to Housing, security, good healthcare, quality education, training, and a chance for personal progress and fulfillment.It is unfortunate that 183 years after so-called “full Free” some 700,000 Jamaicans have no legal ownership of the land on which they and their families have lived and worked for successive generations.It is for this reason that I recently established a Land Commission to prepare a policy framework that will establish a legal pathway to a Land title for those Jamaicans who are still squatters in the land of their birth. This is the commitment of the Opposition when next we form the government.Unfortunately, while we have achieved legal freedom, there still persists a slavery of the mind.It was this condition that led National Hero Marcus Garvey to recognize the need for “emancipation from mental slavery”. As Bob Marley said “none but ourselves can free our minds”.We must never forget the sacrifices and the efforts of those who gave their all in order to build a Jamaica that offers opportunity for all the people, and where families and communities live in harmony with each other free from crime, corruption and oppression.As we celebrate Emancipation Day let us recommit ourselves tothe vision of our ancestors, who wanted to build a country, nurture our children, care for the elderly and infirm, and give every Jamaican the opportunity to develop materially and spiritually.As we pursue this mission, let me wish for you all a restful, happy and safe Emancipation Day. May God continue to bless you and bless our country – Jamaica, land we love. I greet you in the spirit of the freedom that we now celebrate annually on Emancipation Day. Story Highlights The celebration of Emancipation Day shouldbe recognized as the bedrock on which ordinary Jamaicans with extra-ordinary bravery and vision forced the refashioning of our nation’s cultural, social, economic and political arrangements.last_img read more

Of Einstein and entanglement Quantum erasure deconstructs waveparticle duality

first_img Explore further Another challenge was employing hybrid path-polarization entangled photon pairs distributed over the optical fiber and free-space links. “In order to implement the quantum eraser,” Ma continues, “we maintained the entanglement between the path and the polarization of two photons and kept the phase and polarization stable over the measurement duration.” More information: Quantum erasure with causally disconnected choice, PNAS January 22, 2013 vol. 110 no. 4 1221-1226, doi:10.1073/pnas.1213201110 Related: 1The Present Situation in Quantum Mechanics: A Translation of Schrodinger’s ”Cat Paradox” Paper, translated by John D. Trimmer, originally published in Proceedings of the American Philosophical Society, 124, 323-38 (1980) Citation: Of Einstein and entanglement: Quantum erasure deconstructs wave-particle duality (2013, January 29) retrieved 18 August 2019 from https://phys.org/news/2013-01-einstein-entanglement-quantum-erasure-deconstructs.html Specifically, for the polarization states, they had to compensate the polarization rotation and depolarization caused by optical fibers via various tubing and frequently monitoring the polarization transmission fidelity. “For the path states,” Ma illustrates, “we had to isolate the system photon from phase noises, which reduce interference visibility.” In order to achieve that, they used home-made acoustic-isolation surroundings to protect the interferometer. In future experiments, notes Ma, the scientists are planning to develop a brighter photon-pair source, low-noise single-photon detectors, faster optical modulators with higher duty cycles, and more precise clock synchronization. “In our experiment, another practical challenge is limited signal-to-noise ratio” says Ma. “This is because most quantum phenomena are very fragile to noise and can be easily washed away.” To overcome this problem and demonstrate the counterintuitive features of quantum mechanics, the researchers have to increase the signal and/or reduce the noise. “To increase the signal,” Ma continues, “we have to generate more photons. Therefore, a brighter photon-pair source will be certainly helpful. Additionally, more precise clock synchronization will also improve our results: It will allow us to use a much smaller coincidence window and hence reject the false coincidence stemming from noise. This is possible because time-energy entanglement allows the intrinsic uncertainty of the generation time of photon pairs to be much smaller than the timing jitter of the present remote clock synchronization techniques – for example, the GPS system used in their current study. Finally, Ma points out that noise is mainly from the dark counts of single-photon detectors. Therefore, it is very crucial to reduce these dark counts, which is possible by using some advanced cooling techniques. “All these improvements can be evaluated by using photon counting and entanglement verification.”Ma also says that quantum communication and quantum information processing may benefit from their findings. “Our experiment is important for foundations of quantum mechanics as well as quantum information processing, especially quantum communication. The architecture of our experiment could be used for a satellite-to-ground station quantum communication prototype and hence provide the basis for a worldwide information network, in which quantum mechanical effects enable the exchange of messages with greater security and the ability to perform certain calculations more efficiently than is possible with conventional technologies.” Copyright 2013 Phys.org All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of Phys.org. A non-causal quantum eraser Concept of our quantum eraser under Einstein locality conditions. Hybrid entangled photon-pair source, labeled as S, emits path-polarization entangled photon pairs. System photons are propagating through an interferometer (Right) and the environment photons are subject to polarization measurements (Left). Choices to acquire welcher-weg (which-path) information or to obtain interference of the system photons are made under Einstein locality so that there are no causal influences between the system photons and the environment photons. Copyright © PNAS, doi:10.1073/pnas.1213201110 Addressing these challenges meant doing things differently than all quantum eraser experiments performed to date, in particular by establishing strict Einstein locality between the relevant events. “We achieved this by implementing independent active choices that were space-like separated from the interference,” Ma explains. “These choices were made by a quantum random number generator and then implemented by an electro-optical modulator.”When two events are separated by a space-like interval, not enough time passes between their occurrences for there to exist a causal relationship crossing the spatial distance between the two events at or below the speed of light. While the two events can be observed to occur at the same time, there is no reference frame in which the two events can occur in the same spatial location or where they can occur in each other’s future or past.To maintain entanglement between the path and the polarization of photon pairs, Ma points out that the researchers first produced bright highly-entangled polarization pairs using a spontaneous parametric down-conversion process. “We converted the polarization states of the system photon into its path states in an interferometer via a polarizing beam splitter and polarization controllers, while maintaining the polarization state of the environment photon. By carefully adjusting these components, we eliminated the polarization distinguishablity of the path states of the system photon and generated hybrid entangled photon pairs. In order to maintain this hybrid entanglement, we paid exceptional attention in keeping these photons away from decoherence.” (Phys.org)—Quantum physics presents several counterintuitive features, including entanglement, tunneling and – as demonstrated in double-slit experiments – wave-particle duality. When studying wave-particle duality, however, so-called interferometric quantum eraser experiments – in which wave-like behavior can be restored by erasing path information – allow researchers to perform differential measurements on each of two entangled quantum systems. (Double-slit experiments not involving quantum erasure utilize superposition of single particles, while in quantum eraser experiments two particles are entangled.) Specifically, the particle feature’s welcher-weg (which-path) information is erased (or not) from one system, and interference-based measurements in the other system are used to observe (or not, as the case may be) its wave feature. While previous quantum eraser experiments made the erasure choice before or (in delayed-choice experiments) after the interference – thereby allowing communications between erasure and interference in the two systems, respectively – scientists in Prof. Anton Zeilinger’s group at the Austrian Academy of Sciences and the University of Vienna recently reported a quantum eraser experiment in which they prevented this communications possibility by enforcing Einstein locality. They accomplished this using hybrid path-polarization entangled photon pairs distributed over an optical fiber link of 55 meters in one experiment and over a free-space link of 144 kilometers in another. Choosing the polarization measurement for one photon decided whether its entangled partner followed a definite path as a particle, or whether this path-information information was erased and wave-like interference appeared. They concluded that since the two entangled systems are causally disconnected in terms of the erasure choice, wave-particle duality is an irreducible feature of quantum systems with no naïve realistic explanation. The world view that a photon always behaves either definitely as a wave or definitely as a particle would require faster-than-light communication, and should therefore be abandoned as a description of quantum behavior. What does this mean for scientists describing a quantum state without relying purely on mathematics? One way, says Dr. Xiao-Song Ma, lead author of the paper, is that the quantum state can be viewed, as Erwin Schrödinger wrote1, as an expectation-catalogue or sum of knowledge – that is, a probability list for all possible measurement outcomes. Whether the outcome of each individual measurement is wave, particle or their superposition depends on the state and measurement context.Ma also discussed the challenges he, Prof. Anton Zeilinger and their colleagues faced in conducting their research with Phys.org. “The main challenge of our quantum eraser experiment is the arrangement of the individual events such that various space-time configurations, including Einstein’s locality condition, were fulfilled,” Ma says. Achieving that required separate labs, a quantum random number generator, a very fast electro-optical modulator, precise optical and electrical delays, and other sophisticated techniques. (A) Scheme of the Vienna experiment: In Lab 1, the source (S) emits polarization entangled photon pairs, each consisting of a system and an environment photon, via type-II spontaneous parametric down-conversion. Good spectral and spatial mode overlap is achieved by using interference filters with1-nm bandwidth and by collecting the photons into single-mode fibers. The polarization entangled state is subsequently converted into a hybrid entangled state with a polarizing beam splitter (PBS1) and two fiber polarization controllers (FPC). Interferometric measurement of the system photon is performed with a single-mode fiber beam splitter (BS) with a path length of 2 m, where the relative phase between path a and path b is adjusted by moving PBS1’s position with a piezo-nanopositioner. The polarization projection setup of the environment photon consists of an electro-optic modulator (EOM) and another PBS (PBS2). Both photons are detected by silicon avalanche photodiodes (DET 1–4). The choice is made with a QRNG (44). (B) Space–time diagram. The choice-related events Ce and the polarization projection of the environment photon Pe are space-like separated from all events of the interferometric measurement of the system photon Is. Additionally, the events Ce are also space-like separated from the emission of the entangled photon pair from the source Ese. Shaded areas are the past and the future light cones of events Is. This ensures that Einstein locality is fulfilled. BS, beam splitter; FPCs, fiber polarization controllers; PBS, polarized beam splitter. Copyright © PNAS, doi:10.1073/pnas.1213201110 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. Satellite image of the Canary Islands of Tenerife and La Palma and overview of the experimental setup (Google Earth). The two laboratories are spatially separated by about 144 km. In La Palma, the source (S) emits polarization entangled photon pairs, which subsequently are converted to a hybrid entangled state with a PBS (PBS1) and a half-wave plate oriented at 45°. The interferometric measurement of the system photon is done with a free-space BS, where the relative phase between path a and path b is adjusted by moving PBS1’s position with a piezo-nanopositioner. The total path length of this interferometer is about 0.5 m. The projection setup consists of a quarter-wave plate (QWP), an EOM, and a PBS (PBS2), which together project the environment photon into either the H/V or +/− basis. Both the system photon and the environment photon are detected by silicon avalanche photodiodes (DET 1–4). A QRNG defines the choice for the experimental configuration fast and randomly. A delay card is used to adjust the relative time between the choice event and the other events. Independent data registration is performed by individual time-tagging units on both the system and environment photon sides. The time bases on both sides are established by global positioning system (GPS) receivers. Copyright © PNAS, doi:10.1073/pnas.1213201110 Journal information: Proceedings of the National Academy of Scienceslast_img read more