Could primordial black holes be dark matter

first_img(PhysOrg.com) — “We know that about 25% of the matter in the universe is dark matter, but we don’t know what it is,” Michael Kesden tells PhysOrg.com. “There are a number of different theories about what dark matter could be, but we think one alternative might be very small primordial black holes.” 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. Black hole, star collisions may illuminate universe’s dark side When many of us think about black holes, we think of a huge cosmic event, sucking in everything around it. However, there is also the possibility of small black holes. “Einstein’s theory of relativity allows for black holes,” Kesden, a theoretical physicist at New York University, explains, “but doesn’t stipulate a size. It’s very possible that the early universe produced very small black holes. These would gravitate like massive black holes, floating through the universe and clustering.”Kesden worked with Shravan Hanasoge, from Princeton University and the Max Planck Institute for Solar System Research, to work out method of using solar oscillations to determine whether a small, primordial black hole passed through a star. If the data can show that these small black holes formed near the beginning of the universe do exist, they might make good candidates for dark matter. Their work can be seen in Physical Review Letters: “Transient Solar Oscillations Driven by Primordial Black Holes.”“Our approach is to consider what happens if you have dark matter made of primordial black holes passing through the sun,” Kesden says. “It’s been thought of before, but no one has actually done the calculations that we have.”Kesden explains that the sun creates energy from the nuclear fusion at its center: “There is a balance between the outward pressure gradient due to the energy released by fusion and the inward force of gravity. If the sun, or any star, is perturbed it would shake a little.” “A small, primordial black hole would be the size of an atom but have the mass of an asteroid,” he points out. “Its strong gravitational field, as it cut through the sun, would squeeze it, then release, and cause the sun to oscillate before ultimately settling down.”The idea is to measure the oscillation, and determine what would cause it. “Shravan Hanasoge wrote a program to help us with a simulation to see what the sun would look like if a primordial black hole passed through. The smallest mass detectable is 10^21 grams,” Kesden continues. Now that Kesden and Hanasoge know what to look for, it is possible to measure the oscillations of different stars. Since these primordial black holes are thought to be moving through the universe, it should be observable in different stars. “By inferring the total amount of dark matter in the universe, it should be able to determine how often a primordial black hole would pass through the sun – if it’s dark matter,” Kesden says. Unfortunately, dark matter would only pass through the sun every millions of years. “That’s a long time to stare at our sun, waiting for the event.”Instead of waiting millions of years for a primordial black hole to pass through our sun, it is possible to monitor millions of stars; one of these stars would likely encounter a primordial black hole every few years. Kesden points out that current and future space missions could collect the needed data. “It is possible to look at the data collected from asteroseismic missions for these events, now that we know what to look for. Someone could even look through data collected in the past to try to spot these oscillations.”“At the Large Hadron Collider, some scientists are trying to determine if supersymmetry is dark matter,” Kesden says. “But if it isn’t found at the LHC, people will begin looking for other alternatives, and primordial black holes might be the answer to the outstanding question of what dark matter is.” Copyright 2011 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.center_img Explore further Citation: Could primordial black holes be dark matter? (2011, September 21) retrieved 18 August 2019 from https://phys.org/news/2011-09-primordial-black-holes-dark.html More information: Michael Kesden and Shravan Hanasoge, “Transient Solar Oscillations Driven by Primordial Black Holes,” Physical Review Letters (2011). Available online: link.aps.org/doi/10.1103/PhysRevLett.107.111101last_img read more

Mathematicians settle 30yearold resonance controversy

first_img More information: Sabine Bögli, et al. “Guaranteed resonance enclosures and exclosures for atoms and molecules.” Proceedings of The Royal Society A. DOI: 10.1098/rspa.2014.0488 © 2014 Phys.org Explore further In the early ’80s, several researchers were working to determine the location of atomic and molecular resonances, which are the frequencies at which atoms and molecules prefer to oscillate. Two groups of researchers (Rittby, et al., and Korsch, et al.), each using a different method, came up with different locations for these resonances. Settling the dispute proved to be extremely difficult due to the fact that neither method could predict the actual resonances, but instead simply gave approximations. In fact, at the time there was no way to locate resonances with absolute certainty. Journal information: Proceedings of the Royal Society A Citation: Mathematicians settle 30-year-old resonance controversy (2014, November 3) retrieved 18 August 2019 from https://phys.org/news/2014-11-mathematicians-year-old-resonance-controversy.htmlcenter_img The controversy remained unsettled for the last 30 years. But now in a new study, mathematicians have presented a method that, for the first time, can locate resonances with absolute certainty and high accuracy. The method can also tell when approximations fail to lie near true resonances. Using this method, the researchers could show which approximations from the two groups in the ’80s were accurate, and which were not, finally settling the controversy.The mathematicians, Sabine Bögli, et al., from the University of Bern in Switzerland, Cardiff University in the UK, Stockholm University in Sweden, and Regensburg, Germany, have published their paper on the new method for determining resonances in a recent issue of the Proceedings of The Royal Society A.A key ingredient in the new method is interval arithmetic. By operating on intervals rather than numbers, interval arithmetic allows every computational step to be carried out with absolute certainty. Interestingly, interval arithmetic has recently been used in a variety of areas, including navigation of an autonomous robotic sailboat, optimization of a spacecraft traveling between planets, and improvement of stability in particle accelerators.In this study, the researchers used interval arithmetic to prove with absolute certainty that the approximations of resonances in Rittby, et al., do lie near true resonances, whereas the approximations of higher resonances in Korsch, et al., do not. The new method also reveals additional information, in particular the existence of two new pairs of resonances that were originally suggested in a previous paper (Abramov, et al.), but not predicted by either Rittby, et al., or Korsch, et al. The researchers explained that this part was the most challenging because these pairs are so close to the imaginary axis, and the resonances in each pair are so close to each other. The results could have implications for a wide variety of areas.”Resonances are ubiquitous in physics, e.g., in mechanics, acoustics, and electrical circuits,” coauthor Marco Marletta, Professor at Cardiff University in the UK, told Phys.org. “In atomic physics, resonances are associated with metastable states of a system having a sufficiently long lifetime to be well-characterized and to render them significant experimentally and theoretically. The imaginary part of a resonance is related to the decay rate or inverse lifetime of the system.”The researchers explained that the work could be applied to some very computationally challenging problems.”For problems with complex eigenvalues (such as resonances in complex scaling), numerical computations are prone to be unreliable because small errors in input data may result in large errors in the results and/or because spurious eigenvalues may occur (spectral pollution),” explained coauthor Christiane Tretter, Professor at the University of Bern in Switzerland, and from Stockholm University in Sweden. “Therefore methods guaranteeing absolute certainty such as interval arithmetic may prove to be highly useful.” Credit: Wikipedia / CC BY-SA 3.0 Ground-breaking insights into quantum chaos in ultracold gas 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.last_img read more

Get touched by RajasthanIII

first_imgFor another peek into the marvels of the open art gallery of Rajasthan: pack your bags and hit the road for the town that lies in the heart of Shekhawati region- Dunlod. A blend of Mughal and Rajput architecture awaits you at the Dunlod fort founded in 1750, merely 250 km away from Delhi. While you are at it, why not have a taste of the royal times and travel around riding the finely bred horses or hop onto a camel safari; see the town where the fort has been converted into a heritage property offering a cosy and royal stay to the travelers. It features Diwan-e-khas (Hall of Private Audience) that has stained glass windows, fine antiques and an impressive library; along with the first floor marked as ‘zenana’ quarters that has an exquisite décor and furniture. Also Read – ‘Playing Jojo was emotionally exhausting’Its magnificence continues in the Goenka haveli, built in the year 1875 AD in the kingdom of raja of Dunlod. Explore its beautiful frescoes, fine mirror work above the windows and features of florets, and birds in the courtyard. The splendid haveli now hosts a newly established museum- Seth Arjun Das Goenka Haveli museum that curates the relics of Goenka household. The haveli symbolizes the vision of Arjun das:  functional efficiency with panoramically aesthetic views from wherever you choose to stand. The wooden doors of the museum are adorned with eye catching carving that is reminiscent of the old traditional woodwork of Shekhawati.last_img read more

All in an another way

first_imgAll art enthusiasts can head on to Kumar Gallery as it brings to us the show Confluence of Consciousness, the recent paintings of Shampa Sircar Das. Das uses philosophy and aesthetics, encompassing a layers of consciousness and realised awareness through individual and shared journeys. The work is based upon imagination, fuelled and inspired by mythology rich and complex in Buddhist and Vedic pantheons. As in sacred or spiritually based art, the image assists a viewer, creator, and participant, to shed his/her separateness and join in a broader cosmic dance of realisation. Also Read – ‘Playing Jojo was emotionally exhausting’Th canvases are over-laid with adapted Himalayan imagery which although resonant and in parts quite beautiful lacked a cohesion and sense of wholeness which appear in these paintings. Das creates layers of paint with brushes and rollers upon her canvas. Abstract particles and symbols of the belief she refers to as many hidden things as in life. In her words, form later emerges and blocks of colour assume shape, to reveal a fluid, tangeld work of intricate dimension. Of plural existence, such has become fused, these worlds retain shared essence, as in the Vedic maxim, Aham Brahmasmi (I am Brahman), base of the principle of adavaita (nonduality), and the fundamental belief in the inherent residence of Buddhahood in every living being. Transience and a sense of movement in these paintings touch the viewer with the play between form and emptiness. The patterned textures resemble delicate sutras on silk, with glimmers of concrete reference and beneficent beings. Also Read – Leslie doing new comedy special with NetflixParts of world both known and perceived, such manifestations question what is equal in this embrace of immanence and naturalism. Her work of vajras, golden deer, mudras and mandalas, ephemeral beings and textile-like patterns like continuous energy, reflect the limitations of conceptual reality. One work in this exhibition bears accord with a Chinese Tang dynasty Buddha has been documented over the last three years by the most highly developed 3D technology to depict the intricate carvings across the body of the life of Buddha.  As a distinct voice, Das visions are replete with shunya, purusha, and the five elements (tattva), denoting the natural powers which surround one, and the myriad levels which guide one to higher climes.When: 30 April – 15 MayWhere: Kumar Gallery, 56 Sundernagar Timing: 7-9 pmlast_img read more

Leap of faith

first_imgA  fun filled story telling session was held at the launch of part ll in Hanuman Trilogy Amma, Tell Me How Hanuman Crossed the Ocean!’.The story-telling session was attended by Delhi’s mommies along with their kids. Spotted at the event were famous author Sreemoyee Piu Kundu, choreographer Aparna Behl , Simran Sawhney, photographer Sumiko Murgai Nanda along with their kids who had a gala time at the interactive session.As author Bhakti Mathur read out the characters from the book, Hanuman, bear, snake and Lankini came alive when the children donned the costumes of the characters from the book and engaged in role plays.  Also Read – ‘Playing Jojo was emotionally exhausting’The fun and joy of exploring the mythological world left the children thoroughly entertained. Face painting and tattoo sessions was another crowd pleaser at the event. Speaking at the launch at Caffe Tonino, Mathur said, “I’m excited to launch my second book on Hanuman triology and thrilled to see that the kids in India enjoy mythology in today’s technology driven environment”. “Hanuman is a great teacher as he teaches us the value of life and the mantra to live by —with great power comes with great responsibility”, she further added.  In this new and epic story, Hanuman leaps across a mighty ocean, with his forgotten powers regained, and with his strength, wit and devotion.It is a story of how he charmed a mountain, defeated a dragon and crushed a snake. The story talks about the mighty Hanuman who fought the powerful guard of Lanka, on his great mission for Rama’s sake.last_img read more

Govt may push for vote on GST Bill

first_imgLast days of the ongoing Monsoon session have turned into a nerve- wracking battle between the treasury Benches and the principal Opposition Congress. Spurred by criticism of the Congress strategy to stall the functioning of both the Houses, first by the Samajwadi Party and on Tuesday by the Biju Janata Dal (BJD), the government may push for a vote on the GST Bill on Wednesday. According to government sources, the Bill would be passed and it would provide an opportunity to the treasury Benches to further isolate the principal Opposition and strengthen the charge that they were anti-development. “We have the option of going for special session for the passage of the Bill, if it doesn’t happen during the current session,” said a BJP leader.  Also Read – Need to understand why law graduate’s natural choice is not legal profession: CJIIn what could be music to the ears of ruling NDA, the Opposition BJD on Tuesday attacked the Congress in Parliament over disruptions, saying “manifestation of fascism” was being witnessed inside the House. BJD members voiced displeasure both in Lok Sabha and Rajya Sabha over disruptions, becoming the second Opposition party after Samajwadi Party to target Congress for stalling Parliament.Meanwhile, the government on Tuesday moved the goods and services tax (GST) bill in Rajya Sabha for consideration, but a debate on it was blocked by a vociferous Congress which raised procedural issues.    Also Read – Health remains key challenge in India’s development: KovindFinance Minister Arun Jaitley, who moved the much-delayed bill, slammed the Congress, saying the party was raising various issues just to stall the country’s economic growth.Amid slogan-shouting by Congress members, he said the Congress was using Lalit Modi issue against External Affairs Minister Sushma Swaraj as a “pretext” to stall the important tax legislation. Deputy Chairman PJ Kurien said since it was a Constitutional Amendment Bill, the House had to be in order for its passage and adjourned the proceedings till Wednesday. “This being a Constitution Amendment Bill, I cannot take up the Bill in pandemonium,” said Kurien, as he adjourned the House. Jaitley said disruptionist politics were dangerous both for the Congress and the country and he appealed to the principal Opposition party to “see reason and come on the path of cooperation particularly in relation to policies they themselves had at one stage proclaimed”.“We on behalf of the government, along with the support of all parties who are supporting the GST, are determined to pursue this and will take all correct measures politically and constitutionally to achieve this goal,” he said, indicating that the government was preparing to push the major tax reforms Bill before the session ends on Thursday.last_img read more

Nagerbazar blast CID officers take statements of injured victims

first_imgKolkata: Officers of the Criminal Investigation Department (CID) took the statement of fruit seller Ajit Halder, who was injured in the blast at Nagerbazar.Sources said that the CID officers went to RG Kar Medical College and Hospital on Friday and took statements of the people who were injured in the blast.The investigating officers had attempted to record the statement of Halder earlier, but it became impossible due to his health condition. So the CID officers went to the spot on Friday again and recorded his statement. Also Read – Rain batters Kolkata, cripples normal lifeIt may be mentioned that a blast at Nagerbazar had killed an eight-year-old boy on Tuesday. Initially, the Barrackpore Commissionerate had initiated a probe in this connection. Later, the case was handed over to CID. The blast was suspected to have taken place due to a socket bomb.Chief Minister Mamata Banerjee on Friday said in a Press conference that the probe has been handed over to CID. The investigating agency is probing the incident and they will unearth the truth. She further said that the people involved will be arrested and law will take its course. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedThe incident led to panic among local people and shops in the area remained closed for the past two days. However, normalcy is gradually getting restored at Nagerbazar as some of the shops in the area were found open on Friday.Trinamool Congress MP Sougata Roy visited the spot on Friday. He said: “CID is probing the incident and they will find out the facts behind it. We are always with the local people. I would like to assure that there is nothing more to panic about.”He was accompanied by chairman of South Dum Dum Municipality Panchu Roy. He claimed that the bombs were kept there targetting them.last_img read more

Willpower matters love cures

first_imgCansurvive, a literary adaptation of the book ‘CANSURvive: Subah Ka Pata’ written by Asif Ali which deals with the life of cancer patients, their struggles and thereby creating awareness on the disease.Seasoned director and former National School of Drama (NSD)alumna , Vandana Vashisht, beautifully depicts how cancer survivors grapple with the disease and their inner turmoil.   Rajni and Kamal, the two main protagonists both potray cancer survivors and play revolves around how they finally conquer the dreaded disease. Also Read – ‘Playing Jojo was emotionally exhausting’Both the pivotal characters are a study in contrast. While, Rajni is full of life, chirpy and optimistic refusing  to give in, Kamal on the other hand is brooding and gripped in melancholy and always mourning. Showing two sides of the coin, the play provides insight on how the presence of a support system helps a cancer patient win the battle for life.Rajni has her doting husband supporting her on every step of her fight whereas Kamal is ploughing a lonely furrow. Also Read – Leslie doing new comedy special with NetflixThe director succeeded in showing how the desire to live can defeat death itself. Vashisht shows how affection from loved ones can alleviate one’s suffering. Some humour was also weaved in which provided much needed break to the audience. The lighting was very well taken care off and was in sync with the theme.The cast included the likes of Sonal Jha ( Balika Vadhu), Bhupesh Kumar Pandya (who  featured in Vicky donor), Sajida and Vivek (NSD alumni). All the actors did full justice to their characters.The music was given by eminent music director Kajal Ghosh. The contemporary dance to express the emotions of the patients during their treatment added glint to the play. From hand movements to expressions, the choreography too was graceful.The play concluded on the note that apart from one’s willpower, love from family can prove to be a catalyst in recuperation.last_img read more

Adenovirushit children vulnerable to bronchiolitis say doctors

first_imgKolkata: Children affected with adenovirus are a cause of concern for the city doctors as the affected patients often develop respiratory problems even after they are released from the hospitals.According to the doctors, the children, who are once affected with adenovirus, are later developing serious lung infection which the doctors termed as ‘bronchiolitis obliterans (BO). Otherwise known as popcorn lung and constrictive bronchiolitis, the disease causes obstruction to the smallest airways of the lungs (bronchioles) due to inflammation. Symptoms include a dry cough, shortness of breath and feeling tired. Also Read – Rs 13,000 crore investment to provide 2 lakh jobs: MamataThe affected children are developing lung infection, which eventually leads to pneumonia. Children are more susceptible to the virus due to their low immunity. The infection can spread fast among the children who tend to be in close contact with the affected ones. Earlier, it was difficult to identify the virus. Respiratory problem, sore throat, fever, persisting cough and cold are the signs of the virus. It has also been learnt that some children and a few elderly patients have been under Also Read – Lightning kills 8, injures 16 in statemedication at various hospitals in the city with similar symptoms. More than 100 children have been affected with adenovirus in past couple of months. What is worrying for the doctors is that many of the children who return home after being cured, again complaining respiratory distress. As there is no specific medicines for the disease the situation is further complicated. It may be mentioned here that more than 20 babies were admitted at the Institute of Child Health with adenovirus most of them have been released from the hospital after treatment. Many other private hospitals in the city also admitted patients with the same disease. The babies who have been admitted to the hospital are aged between four months and one year. Adenovirus can be a serious cause when it comes to morbidity and mortality. According to a senior official of a private hospital in Park Circus, there is also a crisis of influenza vaccine due to the rising number of viral infection patients in the past three months. There is no proper vaccine for adenovirus and hence the doctors are administering other medicines to the patients. If fever keeps recurring despite medication, the patient should be taken to the hospital and also if they complain of irritation in eyes or muscle pain. Adenovirus appears to be like a common respiratory tract infection. Antibiotics do not properly work when the patient is affected with this virus. If the symptoms persist for more than two to three days, the cause should get investigated without further delay, a senior official of the private hospital said.last_img read more

Massive security arrangements in place 6000 cops deployed for mega rally

first_imgKolkata: The Kolkata Police will have stringent security arrangements and at the same time a comprehensive traffic management plan for the Trinamool Congress (TMC) Martyrs’ Day rally on Sunday.A senior official of the Kolkata Police said on Saturday that there will be 6,000 police personnel deployed. There will also be three Quick Response Teams (QRT), Heavy Radio Flying Squads (HRFS), four teams of the Kolkata Police’s Reserve Police Force in action. Also Read – Rs 13,000 crore investment to provide 2 lakh jobs: MamataThe city police have already come up with five watch towers and roads leading to the venue of the rally have been divided into 10 zones. 100 CCTVs have been installed in and around the rally area to keep a close watch on the movement of party supporters who will be holding processions from different parts of the city including Howrah and Sealdah stations and converge at the site of the rally. There will be four Deputy Commissioners supervising the arrangement. 40 police pickets have been set up at different locations in and around the city. Also Read – Lightning kills 8, injures 16 in state”We are ready to make traffic diversions as and when necessary to ensure that the traffic movement is normal,” a senior official of the Traffic department said. A sub-control room has also been set up on the terrace of the Victoria House (CESC Building), beside the venue to keep a close watch on the movement of the masses. There will be bomb squad personnel and dog squads to prevent any untoward incident. The Kolkata Police have arranged for 18 trauma care ambulances at different locations in and around the city with eight giant screens being erected at different corners of the city. No goods carriage including trucks, matadors will be allowed to enter the city from 4 am on Sunday till 8 pm. TMC observes the Martyrs’ Day every year on July 21 in its bid to pay homage to 13 Youth Congress workers, allegedly killed in police firing in 1993 during the Left Front regime in Bengal. Banerjee will be the main speaker at the event and other senior party leaders will also address the rally.last_img read more