August, 2019 Archive
A Broadband Light Amplifier on a Photonic Chip Citation: Time Lens Speeds Up Optical Data Transmission (2009, September 28) retrieved 18 August 2019 from https://phys.org/news/2009-09-lens-optical-transmission.html 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 further Current methods for speeding up optical data transmission require bulky and expensive optical equipment and consume a lot of energy. This new device is both energy efficient and is incorporated on a silicon chip. This makes it ideal to move large quantities of data, at speeds up to 270 gigabits per second over telecommunication facilities and other optical devices.Alexander Gaeta, Cornell University Professor of Applied and Engineering Physics, explains: “As you get to very high data rates, there are no easy ways of encoding the data.” Alexander Gaeta has been one of the foremost developers of the new silicon time lens, alongside with his colleague Michael Lipson, who is a Cornell University associate professor of electrical and computer engineering. Their accomplishment can be found in the latest issue of the renowned scientific journal, Nature Photonics. Keren Bergman, Columbia University Professor of Electrical Engineering, explains: “Power consumption is becoming a more constraining issue, especially at the chip level. You can’t have your laptop run faster without it getting hotter.” Optical chips can make computers run much faster without generating the un-necessary heat. Using an ultrafast modulator, it can compress data encoded with standard equipment to very high speeds. The “time lens” uses a signal encoded on laser light using a conventional modulator. The modulated light signal is then attached to the silicon chip through an optical-fiber coil that sends it to a nanoscale-patterned silicon waveguide. On the chip, the signal interacts from a laser, which causes it to split up into different frequencies. The light travels through another strand of fiber cable and sends it to another nanoscale-patterned silicon waveguide, where it interacts with light from the same laser. In the process the signal is re-assembled but with its phase changed. The signal leaves the silicon chip via another fiber cable at 270 gigabits per second. The physics behind the process is very complex but the outcome is accomplished by taking a stream of bits that are traveling slow and making them travel much faster, says Keren Bergman. By staying with silicon, “you can leverage all the technologies that have been developed for electronics to make optical devices,” says Alexander Gaeta of Cornell University. Via: Technology Review© 2009 PhysOrg.com This silicon chip is patterned with waveguides that split optical signals and combine them with laser light to speed data rates.Credit: Alexander Gaeta (PhysOrg.com) — Researchers at Cornell University have developed a device called a “time lens” which is a silicon device for speeding up optical data. The basic components of this device are an optical-fiber coil, laser, and nanoscale-patterned silicon waveguide.
It’s good to have a shady side: Sun and shade leaves play different roles in tree canopies (PhysOrg.com) — Aidan Dwyer, a 13 year old Junior High School student from New York state, noticed that the phyllotaxy of the leaves on trees he was observing while hiking through the Catskill Mountains, did so in the form of a Fibonacci sequence. Wondering if there was a reason for it, he deduced that it might be because such an arrangement provides the most efficient means of solar power collection for the trees. To find out if this was the case, he built a small solar tree from PVC pipe and small solar panels, then built another in a normal flat panel array, attached voltage readers to both, and lo and behold, discovered the tree model array was indeed more efficient, at least during times of low or indirect sunlight. Dwyer won a Young Naturist Award for his efforts after writing and submitting his essay, The Secret of the Fibonacci Sequence in Trees. Explore further Aidan measuring the spiral pattern After analyzing his data, he found that the tree design appeared to be far more efficient than the traditional flat-panel structure during so-called off peak times, such as when the sun was low, and that the model appeared to be close to 50% more efficient overall during the winter. Not bad for someone who’s still a kid.Dwyer theorizes that tree branches have evolved such an arrangement because it’s likely the most efficient pattern available, i.e. the one that best takes into account the shading created by branches or leaves hiding one another from direct sunlight. Citation: 13 year old researcher finds tree inspired solar collection more efficient (2011, August 22) retrieved 18 August 2019 from https://phys.org/news/2011-08-year-tree-solar-efficient.html The spiral on trees showing the Fibonacci Sequence The two models collecting sunlight © 2011 PhysOrg.com 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. With trees, The Fibonacci pattern shows up in the way that limbs spiral around the trunk, specifically in the fraction that arises when computing the number of limbs it takes to complete a run all the way around the tree. Dwyer gives the example of the Oak tree which takes five branches to spiral two times around the trunk, giving the fraction 2/5. This is important because it was the basis of the model he built to replicate the tree structure. Interestingly, to find this fraction, and those of other types of trees, he fashioned his own measuring device out of a clear plastic tube with circle protractors on it. Branch angles were measured by inserting them into the tube.Next, he built a small model tree (mimicking the Oak’s Fibonacci series as closely as possible) out of various sizes of PVC pipe to which he affixed small solar panels. After that, he put together a traditional flat panel solar array comprised of the same size solar panels. Then, after hooking up both to a data logger connected to a voltage meter, he then let them sit. The Young Naturist Awards are given (by the American Museum of Natural History) to two students from each grade, K-12, every year for young scientists who have investigated questions they have in the areas of biology, Earth science, ecology, and astronomy. Dwyer’s entry, took the known, that tree leaves grow in a Fibonacci sequence (where each number is the sum of the previous two) and applied it in a novel way that advanced the study of solar energy.
Gravitational waves were predicted by Einstein’s general theory of relativity. They are distortions in the fabric of space-time and are believed to occur in measurable amounts when massive objects such as neutron stars merge. They’ve yet to be seen, but the consensus among physicists is that they are real. Still, they can’t be labeled a certainty until they are proven to exist by measuring them. That’s what a team of physicists and astronomers the world over plan to do over the next half decade.The idea is to deploy ultra-sensitive interferometers at various points around the globe. They are very large L shaped devices and work by measuring the time it takes for a photon delivered from a laser to move from one end of the device to the other. If a gravitational wave strikes, it should cause the length of the device to change, increasing or decreasing the time it takes for a photon to traverse the distance.Most astrophysics believe that detecting gravitational waves is a matter of course, thus the purpose of deploying interferometers across the globe serves another purpose—discerning where they originated. The hope is that by collecting data at many locations at once, researchers will be able to work together to ascertain the direction from which the waves have traveled, and perhaps figure out what caused them to come about in the first place.Kasliwal reports that the new highly sensitive interferometers will come online sometime in 2017, noting that some of them exist already, though they are not yet sensitive enough to detect gravitational waves. He adds that the project will be a hugely collaborative effort, especially if the interferometers begin detecting a lot of waves. Researchers will have to scramble and work together to get information from the detectors to operators of telescopes quickly enough to figure out where the waves might be coming from. More information: Seeing Gravitational Waves, Science 3 May 2013: Vol. 340 no. 6132 pp. 555-556 DOI: 10.1126/science.1235956AbstractGravity is responsible for the long-range order of the universe. Using Einstein’s general relativity, we now think of gravity as the geometrical curvature of the four-dimensional fabric of space-time (1). Extreme cosmological events such as the merging of neutron stars or black holes induce ripples in the fabric of space-time (see the figure). However, these ripples, or gravitational waves, are extremely weak, and their detection has remained elusive. To measure the small signal, an interferometric detector is required that can detect strain to one part in 1021 (that is, a billionth of a nanometer for a kilometer-length interferometer). Such extreme gravity events are also rare, occurring only once every 10,000 years per galaxy (2). An advanced version of such a detector is designed to find gravitational waves on a regular basis (roughly tens of events annually) beginning in 2017 (3). This heroic experiment alone will be somewhat unsatisfying—gravitational wave interferometers will only be able to hear the wave and detect when something happens (literally “hear” as the operational frequency of tens to thousands of Hertz overlaps with the human auditory range). The interferometers will be blind to exactly where the merger occurs. To locate the source of the gravitational waves, collaboration between the physics and the astronomy communities together with extensive simulations are under way (4). Pulsar survey could help find gravitational waves Explore further Illustration of spacetime curvature. Credit: Wikipedia. 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. Citation: New experiments set to detect gravitational waves (2013, May 3) retrieved 18 August 2019 from https://phys.org/news/2013-05-gravitational.html Journal information: Science © 2013 Phys.org (Phys.org) —Over the next five years, Mansi Kasliwal writes in an astrophysics perspective in the journal Science, researchers will begin setting up experiments designed to detect gravitational waves. Kasliwal, an astronomer with the Observatories of the Carnegie Institution for Science located in Pasadena, California, says momentum is building in the physics community to find proof of the existence of gravitational waves. Thus, far, they are still considered theoretical.
, Astrophysical Journal Earth-like planets have Earth-like interiors The team took a logical approach in creating their model, first inputting data that described as much as is known about the early universe—then next adding data about known exoplanets and also information describing the laws of physics and the way they would work on the elements that made up the universe, and how they would grow or change over approximately 13.8 billion years. They then took a virtual census and found the model had “created” approximately 700 million trillion exoplanets—but, to the surprise of the researchers, the vast majority of them were far older than planet Earth.If correct, the models suggest that Earth is much more unique than other models have been showing in the past few years. This is because it is assumed that if life began on other planets far earlier than on Earth, because it would be much older, it should have matured beyond what we have here on Earth to the point that it would be not only noticeable to us, but likely dominant. But because we have not seen any sign of other life, it appears likely that none is there, or is close enough to spot, which suggests that Earth actually is much more unique than other recent models have been suggesting. The model also suggested that most exoplanets likely exist in galaxies that are a lot bigger than the Milky Way, and orbit stars that are quite different from our sun. To date, space scientists have identified approximately 2,000 exoplanets, clearly a very small proportion of the total amount if the new model is to be viewed as accurate.The researchers acknowledge that their model is based on data that is still only partly understood, and that much of what we have observed to date is still somewhat hazy, thus, it is not clear just how accurate their model really is. (Phys.org)—A small team of researchers, three with Swedish Institutions and one from the U.S. has created a computer model of the known universe and in using it to estimate the number of likely other exoplanets able to hold life, has found that there might be fewer Earth-like planets than has been thought. In their paper they have uploaded to the preprint server, arXiv (soon to be published in The Astrophysical Journal), the team describes how they went about creating their model and what it showed. © 2016 Phys.org Explore further Journal information: arXiv More information: Terrestrial planets across space and time, arXiv:1602.00690 [astro-ph.GA] arxiv.org/abs/1602.00690v1AbstractThe study of cosmology, galaxy formation and exoplanetary systems has now advanced to a stage where a cosmic inventory of terrestrial planets may be attempted. By coupling semi-analytic models of galaxy formation to a recipe that relates the occurrence of planets to the mass and metallicity of their host stars, we trace the population of terrestrial planets around both solar-mass (FGK type) and lower-mass (M dwarf) stars throughout all of cosmic history. We find that the mean age of terrestrial planets in the local Universe is 8±1 Gyr and that the typical planet of this type is located in a spheroid-dominated galaxy with total stellar mass about twice that of the Milky Way. We estimate that hot Jupiters have depleted the population of terrestrial planets around FGK stars at redshift z=0 by no more than ≈10%, and predict that ≈1/3 of the terrestrial planets in the local Universe are orbiting stars in a metallicity range for which such planets have yet to be been detected. When looking at the inventory of planets throughout the whole observable Universe (i.e. in all galaxies on our past light cone) we argue for a total of ≈2×1019 and ≈7×1020 terrestrial planets around FGK and M stars, respectively. Due to the hierarchical formation of galaxies and lookback-time effects, the average terrestrial planet on our past light cone has an age of just 1.7±0.2 Gyr and is sitting in a galaxy with a stellar mass a factor of ≈2 lower than that of the Milky Way. These results are discussed in the context of cosmic habitability, the Copernican principle and the prospects of searches for extraterrestrial intelligence at cosmological distances.via ScientificAmerican 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. Citation: Researchers conclude the universe contains fewer Earth-like planets than previously thought (2016, February 24) retrieved 18 August 2019 from https://phys.org/news/2016-02-earth-unique-thought.html This is the “South Pillar” region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope “busted open” this murky cloud to reveal star embryos tucked inside finger-like pillars of thick dust. Credit: NASA
Information Processing Under Reward Versus Under PunishmentTimothy Ballard, David K. Sewell, Daniel Cosgrove, and Andrew Neal What effects do rewards and punishments have on how individuals process information while making a decision? In this study, participants saw successive frames with clouds of moving dots and had to quickly judge whether the dots were moving toward the left or toward the right of the screen. They were given a specific accuracy and quickness goal and they could (a) be rewarded with $2.50 if they achieved the goal (expected reward), (b) be punished by losing $2.50 if they did not achieve the goal (expected punishment), or (c) be neither punished nor rewarded (no incentive). The results pointed to worse performance when punishment was expected. Participants were slower and less accurate when they expected punishment than when they expected a reward or no incentive. Under expected punishment, easy stimuli (i.e., with a larger proportion of moving dots) elicited similar accuracy and response time as did medium-difficulty stimuli under expected-reward or no-incentive conditions, and medium-difficulty stimuli elicited similar accuracy and response time as did high-difficulty stimuli under expected-reward or no-incentive conditions. Using a computational model, the authors found that, compared with expected reward or no-incentive conditions, expected punishment lowered the average quality and quantity of information processed and lowered the amount of information used to make a decision, causing less cautious decision making. Thus, the information individuals extract from the environment and their decision processes seem to be determined not only by the stimuli but also by the task incentives. National Gross Domestic Product, Science Interest, and Science Achievement: A Direct Replication and Extension of the Tucker-Drob, Cheung, and Briley (2014) StudyAnqing Zheng, Elliot M. Tucker-Drob, and Daniel A. Briley Read about the latest research published in Psychological Science: Aggression Toward Sexualized Women Is Mediated by Decreased Perceptions of HumannessSteven Arnocky, Valentina Proietti, Erika L. Ruddick, Taylor-Rae Côté, Triana L. Ortiz, Gordon Hodson, and Justin M. Carré Differentiate to Regulate: Low Negative Emotion Differentiation Is Associated With Ineffective Use but Not Selection of Emotion-Regulation StrategiesElise K. Kalokerinos, Yasemin Erbas, Eva Ceulemans, and Peter Kuppens As the demand for science graduates increases, identifying the key predictors of high performance in science disciplines can help researchers create interventions aimed at increasing science knowledge. In 2014, Tucker-Drob and colleagues examined data from the 2006 Programme for International Student Assessment (PISA) and concluded that across 57 countries, 15-year-old students’ high interest in science was associated with higher science achievement, but this association was stronger for students from advantaged backgrounds (i.e., from families and schools with higher socioeconomic status and from countries with higher national gross domestic product). Zheng and colleagues analyzed data from the 2015 PISA and found similar results across 72 countries. They also found that between 2006 and 2015, the disparities between students from advantaged and disadvantaged backgrounds decreased, and the association between science interest and achievement increased for students from more disadvantaged backgrounds. This increase was more pronounced in less prosperous countries than in rich countries and was accompanied by increases in access to the Internet, education, and higher education expenditures. These findings suggest that increasing the availability of educational resources and removing barriers to learning might allow more students to transform interest in science into knowledge and achievement. Knowing whether you are sad, angry, or anxious when you feel awful (rather than not being able to identify a particular feeling) is known as emotion differentiation, and this ability has been associated with well-being. This may be because low emotion differentiation decreases the successful use of emotion-regulation strategies (e.g., social sharing, expression suppression), this research suggests. Participants sampled their emotions and regulation strategies 10 times a day for 7 days. They received prompts on a smartphone to rate their levels of stress, anger, sadness, anxiety, depression, and loneliness and their use of rumination, distraction from the emotion, reappraisal of the emotion, suppression of the expression of the emotion, and social sharing of the emotion (i.e., talking to other people about it). Emotion differentiation was not related to the specific use of any strategy; that is, it did not increase the use of more adaptive strategies such as emotional reappraisal or sharing. But in lower differentiators, the use of any strategy was more strongly associated with negative emotion than in higher differentiators, which suggests that the strategies were not attenuating negative emotions for low differentiators. These effects were replicated when emotions were sampled around an emotional event: receiving first-semester grades. Differentiation deficits thus seem to impair the successful use of emotion-regulation strategies but not the selection of strategies. Given that differentiation seems to support effective emotional regulation, differentiation training may facilitate regulation in clinical populations. Women with a sexualized appearance (described as an outward physical appearance that signals greater sexual receptivity and promotes greater attractiveness to men) may be victims of aggressive behaviors from other women. In this study, female college students completed a measure of how competitive they are with other women (intrasexual competition) and then viewed a video depicting a female partner who was, in reality, a confederate. The confederate was dressed either conventionally, in a blue long-sleeved shirt with her hair up and no makeup, or in a sexualized way, in a strapless red top with her hair down and face made up. Participants rated the partner’s personality traits and were told they would play a game against the partner. In the game, participants received points by repeatedly pressing a key on the keyboard, but those points could be stolen by the partner. When points were stolen, participants could respond by stealing points back from the partner, but they could not keep the stolen points — choosing to steal points was considered an indicator of aggression toward the partner. Participants who scored higher on intrasexual competition rated the sexualized partner lower in the uniquely human traits of openness to experience and conscientiousness, and those lower ratings were associated with more aggressive behaviors during the game. This effect appeared not to be due to how typical or atypical the partner’s appearance was but solely to how sexualized it was. These findings suggest that dehumanization may be a mechanism through which interacting with a sexualized woman fuels aggression from competitive females.
Festival season is around the corner as is the wedding season. And everyone likes making their homes look good, not just now, all year around! Here are some brilliant tips from Retesh Sharma, Managing Director, Zynna on how to best light up your home in the party season. Whether inside or outside, lights are key to making a house a home.You wouldn’t want a bright overhead light shining down on an intimate dinner party or a single lamp lighting a space where you’re trying to do a project. The main goal of lighting design is to introduce varying degrees of light into a room, which are called layers. Also Read – ‘Playing Jojo was emotionally exhausting’If you only have direct light sources, it will make a space feel dark and gloomy. And if you light the room evenly with no contrast, the room will appear flat and uninviting. Lighting is all about creating interest and visual drama, and these layers of light are parts of the whole that create the ultimate ambiance.Some party occasions call for bright light, but a party isn’t one of them. Your guests will feel relaxed and comfortable if the lights are a bit dimmer than usual. Consider keeping overhead lights turned off, relying instead on lamps, sconces and other light sources. This creates an intimate atmosphere, encouraging everyone to open up and socialize. Also Read – Leslie doing new comedy special with NetflixYour home is already full of light fixtures – pendants, sconces, lamps, and chandeliers. Dress them up for the party. Hang ornaments from ceiling fixtures so they catch the light. Wind greenery and berry branches around a pendant light’s cord or around the branches of a chandelier.Candles add personal touch to the evening. The natural radiance coming from candles sets up the mood as soon as one enters the party. Besides adding light and sparkle, candles come in beautiful varieties of perfumes. These also add up and create mood lighting.
The recommendations of the Standing Committee of Parliament on Urban Development and suggestions of various stakeholders (consumer organisations, industry associations, academia, experts etc.) have also been included after extensive consultations.The Real Estate (Regulation and Development) Bill is a pioneering initiative to protect the interest of consumers, to promote fair play in real estate transactions and to ensure timely execution of projects. Also Read – Need to understand why law graduate’s natural choice is not legal profession: CJIThe Bill provides for a uniform regulatory environment, to protect consumer interests, help speedy adjudication of disputes and ensure orderly growth of the real estate sector. The Bill contains provisions of registration of real estate projects and registration of real estate agents with the Real Estate Regulatory Authority; functions and duties of promoters and allottees; establishment of Real Estate Regulatory Authority; establishment of fast track dispute resolution mechanism through adjudication; establishment of a Real Estate Appellate Tribunal; offences and penalties etc.
With a wedding date set and trousseau shopping on full swing, you need all the time you can get to make a lasting impression on the big day. The first place to start? Your skin, says an expert. Madhu Arora,
At the age of 14, he started his career with sketches further perfecting the art of oil paintings. He has made seven paintings on the eternal divine lovers Radha Krishna. Sometimes, it takes him an hour to paint a beautiful painting while at times even a month seems less.India, known for its art and culture around the globe, does not treat the creators of art the way the artists deserve to be treated. They fail to get the much-needed recognition and the meagre pay cheques make things even more difficult for them. Also Read – ‘Playing Jojo was emotionally exhausting’ Accepting this harsh reality, he started giving art classes to children. Alongside he made many beautiful paintings. From the line of teaching, he was appointed as the President of Lalit Kala Academy in 1984. He brought forth many country’s artists and painted on many social issues such as the plight of women, nature, diversity between men and women. He had inaugurated five Regional Art Centres in Delhi, Lucknow, Calcutta, Orissa and Chennai. He had to leave Lalit Kala Academy due to excessive political, such difficult situations in life had taught him a lot, he said. Also Read – Leslie doing new comedy special with NetflixA man, who believes in simple living and high thinking, is very fond of children. Every Sunday, he guides children to paint and motivates them to pursue their dreams. He makes his students understand that it is good to dream and gives them sincere advice. However, in order to live the dream one must have the courage and perseverance. By donating the money that he earns to poor, he feels content.On March 31 when Bharat Ratna was conferred on educationist Madan Mohan Malaviya, the Srijan Artist Group organised an exhibition where Anand Dev’s painting was sold for Rs 1Lakh. On receiving the money, he sponsored a trip to South Africa for his students.
A multilingual storyteller born in India, Laila Wadia now lives in Italy where she teaches English at the University of Triest. A translator, interpreter, journalist, poet, playwright and screenplay writer, Wadia has won several awards and has published numerous novels and short story collections in Italian on intercultural issues, migration, food and women’s issues including ‘Il testimone di Pirano’ (Infinito Edizioni), and ‘Kitchensutra’.When asked what inspired her to start writing, Wadia said, “I decided to become a writer as a challenge. I had moved to Italy and someone told me I’d never be able to master the language.” Also Read – Add new books to your shelfWadia, who has published books like ‘Pecore Nere’ (Laterza), ‘Mondopentola’ (Cosmo Iannone), ‘Amiche per la pelle’ and ‘Se tutte le donne’ (Barbera 2012), feels that engaging in the act of discovery while writing is just as important as having a fine plot. “I work out a loose plot and then allow my characters to take over”, says Wadia, who feels that it is a writer’s job to create. “The hardest thing about writing any book is deciding when to stop”, she added.Talking about her latest book ‘Kitchensutra’ she said, “‘Kitchensutra’ is a translingual book of erotic food poetry. It’s haikus on love, passion, language and with a two tiered reading: earthly love and divine love. My inspiration was drawn from Rumi and Pablo Neruda.” Also Read – Over 2 hours screen time daily will make your kids impulsive ‘Babylon Sisters’ is an adaptation of Wadia’s novel ‘Amiche per la pelle’ will be released as a movie later this year for which she has also written the screenplay. The movie is about four immigrants of Indian origin, Croatian, Turkish and Kurdish Chinese who live with their families on the outskirts of Trieste. ‘Babylon Sisters’ will be directed by Gigi Roccati who won the award for the best documentary for his direction in The Road to Kabul.Writing characters of the opposite sex is one of the most difficult things a writer has to deal with, while writing. Speaking on this topic, Wadia said, “I am a very feminine writer but I also wrote a fictional biography of a man. Writing means living the character’s life so once I got into the life of the protagonist, it was okay.”Wadia admits that while she herself has not faced the much dreaded writer’s block, she constantly asks herself if people would want to read what she writes.“Success is not a goal for me” says Wadia. “Conversations and bridging cultures is what I strive for. I am a story teller not a writer. A writer writes, a storyteller listens and converses.”