Physicists face a philosophical quandary. Something they deeply wish to believe in does not appear to exist.What happens when your theory requires something but you can’t find it? That’s the situation with dark matter. Scientists around the world have built ultra-sensitive detectors deep in mines to look for “weakly interacting massive particles” (WIMPs) that would theoretically explain why galaxies and galaxy clusters move the way they do. Dark matter is also an essential ingredient for the leading big bang theory. But the most sensitive test ever cannot find it.Photograph of dark matter. Frame and white background provided for contrast.Experimental results from the XENON1T dark matter detector limit the effective size of dark matter particles to 4.1 x 10-47 square centimeters — one-trillionth of one-trillionth of a centimeter squared — the most stringent limit yet determined for dark matter as established by the world’s most sensitive detector.The results, presented Monday in a seminar in Italy at the Gran Sasso Underground Laboratory (LNGS), were produced using an active target volume of 1,300 kilograms of Xenon, the first search for dark matter that has monitored the equivalent of one ton of xenon for an entire year.“We now have the tightest limit for what is known as ‘the WIMP-nucleon cross section,’ which is a measure of the effective size of dark matter, or how strongly it interacts with normal matter,” said Ethan Brown, a member of the XENON Collaboration, and assistant professor of physics, applied physics, and astronomy at Rensselaer Polytechnic Institute. “With these results, we have now tested many new theoretical models of dark matter and placed the strongest constraints on these models to date.“Physicists don’t like to say that dark matter is not there. They prefer saying they have placed tighter limits on where it could be hiding. Space.com makes the same dodge. Nature is more blunt: “Dark matter detector draws a blank.”The world’s largest experiment intended to detect weakly interacting massive particles (WIMPs) has come up empty-handed after collecting data for nearly a year. XENON1T is located 1.4 kilometres underground at the Gran Sasso National Laboratory in central Italy. The experiment looks out for the tiny flashes of light that should be given off when WIMPs — a popular candidate for dark matter, which is thought to make up 85% of the Universe’s matter — collide with atoms in 1,300 kilograms of cold liquid xenon. On 28 May, researchers from the XENON1T collaboration reported at seminars held simultaneously at Gran Sasso and at CERN, Europe’s particle-physics laboratory in Geneva, Switzerland, that no such flashes were detected. The data suggest that WIMPs — if they exist — interact even more weakly with ordinary matter than previously thought.This is like saying that ‘ghosts, if they exist, are faster at escaping from our glances than previously thought.’ The hunt is in a vicious cycle:Dark matter must exist.Build a more sensitive detector.No dark matter found.Return to Step One.Any particle as small as 4.1 x 10-47 square centimeters is, for all practical purposes, non-existent. That’s almost a trillionth of a trillionth of a trillionth of a trillionth of a square centimeter! An electron (10-16 cm) is inconceivably gigantic by comparison. This doesn’t mean that the proposed particle is that small, but its “effective size” or ability to interact with normal matter makes it that small, practically speaking. WIMPs were thought to be quite large, actually (massive), but the “collisional cross section” (size of the interaction target) has now been so narrowed by this latest search that a successful collision would be like hitting a bull’s-eye on earth much smaller than an electron with a dart thrown from another galaxy. And yet these same theoretical particles are proposed to exert so much gravity that they hold galaxy clusters together and keep the big bang from disrupting the fabric of spacetime.Will physicists and cosmologists ever quit their so-far vain attempt to find the mysterious unknown stuff? Quitting would be a huge blow to modern physics. It would mean admitting that the Standard Model is incomplete or, at worst, wrong. A scientific revolution may be in the making.Update 6/02/18: Two physicists at the Harvard-Smithsonian Center for Astrophysics, one of them astronomer Avi Loeb, are assigning properties to dark matter. According to Space.com, they are speculating whether dark matter particles carry an electric charge. Perhaps they should discover the particles first. “The thought that dark matter could somehow be electrically charged seems too bizarre to be anything but science fiction,” reporter Chelsea Gohd admits. The two astronomers base their speculation on one possible interpretation from an instrument called EDGES that measured a particular absorption spectrum in the cosmic background radiation. Still, they confess, “The nature of dark matter is one of the biggest mysteries in science, and we need to use any related new data to tackle it.”We’ve been watching this hunt for years, curious to see how it turns out (e.g., 20 Jan, 2002, 23 July 2007, 9 Jan 2017; search on “dark matter” for more). We’ve used the case of the Mysterious Unknown Stuff (MUST) that must be there as a test of empiricism vs theory. So far, empiricism is winning. Don’t even ask about dark energy. That stuff is even more mysterious, and physicists don’t even have a theory of what it could possibly be. It’s like watching serious scientists in our own time trying to defend belief in ghosts (30 Aug 2016).The search recalls physicists’ vain attempts to look for phlogiston as the cause of combustion, or caloric as the carrier of heat. Those two historical non-detections of the 18th century led to scientific revolutions of their own (the oxygen theory, and the mechanical theory of heat). Some of the champions of those occult substances went to their deaths without admitting they were wrong. Are we seeing another case of it now?We cannot rule out a successful detection. Physicists did find the Higgs boson, didn’t they? Well, at these levels of constraint, any seemingly empirical results become so theory-laden, it’s difficult to ascertain whether they found a real particle or another version of the theory that they can keep believing in. Does that recall a situation in biology? 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In celebration of Mandela Day, here is an essential list of the best Madiba-inspired musical moments. Spend your 67 minutes doing something to honour the man and his life with this soundtrack of great local and international artists paying tribute to South Africa’s greatest citizen. Nelson Mandela dances on stage in October, 1995, with supporters in Johannesburg, South Africa. (Image: Reuters)• South African music• Nelson Mandela – a timeline • Watch: Salif Keita and Black Mambazo call for harmony in Africa• Remembering Mandela, one year on• Jazz trumpets the notes of freedom CD AndersonNelson Mandela called music the “great blessing”, and believed that it has the power to “unite us all to sing with one voice”, to give us all the opportunity to both dream and dance.Madiba inspired a diverse collection of musicians, from ska punkers to classical composers, world-beating rock stars and jazz greats, and they all responded with some amazing tributes.In celebration of Mandela Day, here is an essential list of the best Madiba musical moments, including some of his personal favourites, as well as songs that helped define his place in history and our hearts.While you spend 67 minutes doing something to honour the great man and his life, take a moment to listen to the songs below and join the celebration.Hugh Masekela – Bring Him Back Home One of South Africa’s jazz greats, Masekela spent much of his life in exile, and that longing to return home inspired this somber but powerful lament to both the African diaspora and Mandela himself, the guiding light for those returning home to a new South Africa. Masekela had the honour of playing the song live for Madiba on his release from prison in 1990.Simple Minds – Mandela DayA song celebrating an imprisoned African leader by a Scottish rock band makes for an interesting dichotomy, but it is an appropriate one: Simple Minds’ singer Jim Kerr was one of the more outspoken proponents of the UK’s anti-apartheid movement. This celebratory song is, naturally, the unofficial anthem of July 18th, but a more lasting legacy was its part in bringing the story of Mandela and apartheid South Africa to a global audience during the 1980s.Yvonne Chaka Chaka – Umqombothi According to Chaka Chaka, this song – an upbeat sing-along about traditional African beer – was Mandela’s favourite song of all time. With its bold African groove, catchy chorus and addictive rhythm, it is the perfect fit for our famous Dancing President.Abdullah Ibrahim – MannenbergThe quintessential sound of South Africa, instantly recognised by all its citizens by the rolling piano theme and dynamic tempo. Named after the vibrant District Six area scarred by forced removals during apartheid, the song’s uplifting coda also acts as a perfect motif for a returning hero to free his people.Brenda Fassie – Black PresidentMa Brrr was one of Madiba’s favourite singers, and she celebrated his presidency in 1994 with this impassioned pledge of allegiance to his leadership and his dream for a free South Africa. The song inspired a generation and made her one of the country’s greatest musical icons.Vusi Mahlasela – When You Come BackThe Voice of Mamelodi has enjoyed a long career as a musical storyteller at home and around the world. In 1992, he greeted Madiba and other returning heroes with the “ringing of bells and the beating of drums” in this joyful harmony that quickly become his signature song. The song, much like Mandela, calls for humanity to “give something to the world and not just take from it.”The Specials AKA – Free Nelson MandelaWithout doubt the most famous song about Madiba, this rollicking ska protest song inspired the youth-led anti-apartheid movement across the world during the 1980s. Today, the song’s lyrics still have resonance, highlighting the ideals of Nelson Mandela to overcome poverty through positive action.Johnny Clegg – Asimbonanga (We have not seen him)The live performance of this song says it all: a powerful performer with a powerful song, joined on stage by the most powerful icon in South African history. Asimbonanga is a joyous refrain to all South Africans to be inspired by the life and work of Madiba and use it every day to continue his legacy.U2 – Ordinary LoveWorld citizen Bono has always had a strong connection to Madiba and his ideals, so it was appropriate that U2 was asked to write the theme song for the “Mandela: Long Walk to Freedom” film in 2013. The song, released a week before Madiba died, is a touching final tribute to the great man and his life’s work.Some other great Madiba-inspired tracks to soundtrack your 67 minutes this Mandela Day: Zahara featuring Mzwakhe Mbuli – Mandela Youssou N’dour – Nelson MandelaSipho Hotstix Mabuse – NelsonKoos Kombuis – Madiba BayWilhelm Kaiser-Lindemann – Hommage a Nelson M for Cello and PercussionMiles Davis – Amandla
Share Facebook Twitter Google + LinkedIn Pinterest Cover crops have been promoted for their abilities to reduce erosion and retain or enhance soil nutrients. Now there is evidence that they can significantly reduce weed seeds from entering the soil seed bank.Crops such as red clover, planted after a main crop’s harvest, often are used to provide cover for insects such as ground beetles that feed on weed seed scattered along the soil surface. Beetles remove the seeds before they are tilled under and become part of the field’s long-term seed bank. Rodents are also important consumers of weed seeds and, like beetles, tend to prefer foraging under the shelter provided by cover.As a result, in fields planted with cover crops, three to four times more weed seed is eliminated from the combination of beetles and rodents, according to recent research.While that result wasn’t unexpected, Ian Kaplan, a Purdue University associate professor of entomology, and Carmen Blubaugh, who earned her doctorate at Purdue and is now a postdoctoral research associate at Washington State University, used field experiments to learn a little about how habitat and fear might cause ripples along the food chain and affect seed predation.Beyond eating weed seeds, rodents also attack seed-feeding beetles, making it a challenge to predict seed consumption rates where both mice and beetles coexist. Each face numerous threats that change their approaches to finding food. On dark nights, for example, rodents might roam open fields. But under a moonlit sky, they are vulnerable to nocturnal predators.“We know moonlight has this predictable effect on small mammal behavior,” said Blubaugh, whose findings were published in the journal Oecologia. “When the moon is full, small mammals hide under the protection of cover. It helps them avoid predators that fly at night.”Kaplan and Blubaugh assumed that increasing the amount of light would drive rodents to cover more often, increasing the number of beetles they ate. If that were the case, reducing the beetle population might increase the amount of weed seed left in a field.In field experiments, they artificially manipulated “moonlight” in fields using lanterns to simulate a full moon. They indeed found fewer beetles under the illuminated cover crops, but instead of reducing the rate of weed seed consumption, the light treatments had no effect.“This is particularly surprising and interesting since rodents had strong negative effects on beetle densities,” Kaplan said. “Theory predicts that this interaction — called intraguild predation — will disrupt biocontrol, especially when the weaker seed predator (rodents) attacks the more effective predator (beetles).”In lab tests, exposure to a rodent decreased the movement of beetles, likely their way of becoming less noticeable to the predators. But surprisingly, the beetles ate 50% more seeds, despite the risk of being eaten themselves.“Beetles reduce their movement, but it might just mean that they hunker down on a pile of seeds and use that as a resource instead of hunting around for higher quality food,” Blubaugh said.Blubaugh expects to continue studying the interactions among animals and insects to understand how they’re affected by fear and risk. She said a study of animal feces could inform how diets change in response to fluctuating risk.The National Science Foundation and the U.S. Department of Agriculture’s National Institute of Food and Agriculture funded Kaplan and Blubaugh’s research.
Get the Free eBook! Want to master cold calling? Download my free eBook! Many would have you believe that cold calling is dead, but the successful have no fear of the phone; they use it to outproduce their competitors. Download Now My friend Mike Weinberg says “No one defaults to prospecting.” What he means is that when salespeople have time between calls or meetings, they don’t automatically pick up the phone and start prospecting. And he’s right about this.When I was a young salesperson, there was only the phone. Every morning, I secluded myself in an office and made prospecting calls. I started making calls at 8:15 AM, and I stopped for lunch at Noon, when I’d usually go to a restaurant with my peers. After lunch, I’d start making calls again until it was time to go home.As I made calls to every number in the business section of the phonebook, I wrote down every “good” lead on an index card. If someone told me that they used what I sold, they were a good lead. The next day, I’d flip through all of those index cards, knowing that they were better than the numbers in the phonebook. Then I started back through the phonebook. No targets. No business intelligence. No social networks. No LinkedIn. No research.It was prospecting. All day. Every day. And then the appointments came. And after I made a sales call, it was back to prospecting. Lots of people were better salespeople than I was. No one made more calls. Prospecting was my default.As a young salesperson, no one had to tell me to prospect. I didn’t know what else I should have been doing. And there still aren’t many real choices available to you. When you need new business, you make your calls.Don’t be a sales poseur. Pick up the telephone.I made two cold calls today. Dave Brock and his team make calls every week.
Goa’s Minister for Tourism Manohar Ujgaonkar on Thursday said fish and not beef was the food preferred by tourists and the Centre’s notification banning the sale of cattle for slaughter will have no impact on the flow of tourists to the State. Over six million tourists, both domestic and foreign, visit the State every year.Mr. Ajgaonkar said, “Just as Goa is known for its sun and sand, it is also known for its fish, curry and rice. Goan fish curry is a big draw for tourists who love authentic Goan xit kodi [fish curry] and sea food. Other non-vegetarian dishes are always the second choice. Goa therefore has not really been affected by the beef notification.”Mr. Ajgaonkar said there was no beef shortage in Goa, but tourism industry stakeholders and meat traders are worried the order banning the sale of cattle for slaughter in animal markets would badly hit sale of beef. Over 30% of the State’s population compirse of people of minority communities who consume beef regularly.Francisco Braganca, hotelier and former president of the Travel and Tourism Association of Goa, said hoteliers worry that fears of beef shortage could lead traders hoarding stocks and creating articifical scarcity. He said, “I am told by many supermarket stores owners that there is no impact on the supply of beef as of now. Cattle continues to come in from Karnataka, but the beef is sold out instantly. People perceive a shortage and are hoarding beef.”He said tourists continue to flock to the State as it’s hotter in the other parts of the country.
The colorful snakelike image above is actually fluorescently labeled tissue from a section of a stomach that’s smaller than a pea. But it’s not the stomach of an extraordinarily small animal; it’s a mini human stomach grown in a dish by scientists who hope to use it to study gastrointestinal diseases. Because the digestive systems of mice, flies, and other model organisms differ from those of humans, researchers have been hard-pressed to find a way to study the development of human gut maladies such as peptic ulcer disease. So several groups have turned to pluripotent stem cells—cells derived from human embryos or reprogrammed adult cells that can turn into any cell type in the body—to try to grow digestive organs in the lab. Last week, one group of researchers announced the creation of a lab-grown small intestine from stem cells. Today, a different team reports online in Nature that they’ve perfected the recipe of molecules needed to coax both types of stem cells to grow into small spheres that, despite their size, have all the properties of a functional stomach. When the researchers exposed the ministomachs to the bacterium Helicobacter pylori, infections of which are blamed for many stomach ulcers and cancers, they saw the same molecular and cellular changes already known to occur in life-size stomachs.
Former captain Sunil Gavaskar has blamed poor technique of Indian batsmen for the team’s dismal show in the Test series in England, saying the tourists have looked like a “school boys’ team”.Team India was found wanting in all three departments of batting, bowling and fielding as they were outplayed by the English side.Down 2-nil in the series, Team India’s two losses in the series have exposed a lot of chinks in their armour and experts worry that if India does not improve immediately M.S. Dhoni’s team stand to lose their top Test ranking.Scathing in his criticism of the world number one side, Gavaskar states that the Indians have been “totally outplayed by England in the second Test so much so that it looked like a contest between a professional team and a school boys’ team”.Gavaskar elaborates, “The batting has failed to get to 300 in four innings and the bowling in both Tests has faded away after a bright beginning”.Talking specifically about the batsmen, the master criticises the batting technique of both the seniors and the youngsters in the side: Getting onto the front foot and they suddenly find that when it comes to overseas pitches and the quicker bowlers, “they just don’t know how to play off the back foot”.India just does not care about international commitments: HoldingThe poor show by Dhoni and company in England is drawing flak world wide.Legendary West Indian fast bowler Michael Holding has slammed Indian cricketers for below average performance so far, even claiming that it was the money that was on offer in the IPL that had ensured that the Indians just did not care about their international commitments. The former pacer questioned why none of the players pull out of IPL with injuries, suggesting that the money on offer ensured that international commitments take a back seat. Holding went on to accuse Team India of neither playing like world champions nor putting in extra effort.advertisement
West Indies batsman Darren Bravo has paid a rich tribute to Chris Gayle, calling the opening batsman a “hero to the young players”. Gayle will retire from one day internationals after the ICC Cricket World Cup 2019 to be held in England and Wales.”He’s definitely a hero to the young players. Not even a hero; he’s a legend. The experience of having Chris in the dressing room is priceless. He puts a smile on each and every player’s face. And, as you can see when we go out there, we really enjoy our cricket,” Bravo was quoted as saying by ICC.Gayle holds the record for most centuries by a West Indian in ODIs, with 24, as well as the highest score of 215, which he scored in the last edition of the ICC Cricket World Cup in 2015 against Zimbabwe. Gayle is also handy with the ball, picking up 165 wickets.”If you look at the stats, he’s achieved a lot at the international level. He’s a special player. We’re really happy to have him,” he added.Bravo said that Gayle is still an asset for the team and is the one who always helps the youngster with their game.”He’s getting on a bit in age, but he’s still striking the ball nicely, so that is the most important thing,” he said.”And in the dressing room, he’s always giving information, he’s helping all the youngsters. I think over the last few years he’s changed the game a little bit. He’s not going so hard as before. He understands his game pretty well,” he said.advertisement”As long as it all goes well, as far as his approach is concerned, I don’t see any reason we can’t consistently cross the 300 mark,” he added.The left-hand batsman, who made a comeback after being out of action for sometime, said that he is quite happy with the current atmosphere in the dressing room and is enjoying his style of play.”I’m happy; the guys are smiling. It’s always good to have the best of both worlds. It’s a good feeling. There’s a nice gel of experience and young guys. The fans are enjoying our style of play, which is the most important thing,” Bravo said.West Indies, who are currently playing a five-match ODI series against England at home, open their World Cup campaign against Pakistan on May 31.Also Watch:
U17 World Cup U17 World Cup 2017 – Kochi geared up for its biggest football extravaganza Goal Kochi Correspondent Last updated 2 years ago 05:01 10/5/17 FacebookTwitterRedditcopy Comments(0) Manjappada U17 World Cup Brazil U17 v Spain U17 Brazil U17 Spain U17 India U17 The most happening place in ‘God’s own country’ has opened its doors to FIFA’s U-17 football carnival… U17 WORLD CUP SPECIAL | BY NISANTH V EASWAR Follow @Niktheblue94 on Twitter The FIFA U-17 World Cup in India is all set for kick-off on October 6. A day later is when the carnival will begin at the Kaloor Jawaharlal Nehru (JLN) Stadium in Kochi. For a stadium that packs one of the most football-crazy crowds in the country. to say that Kochi has welcomed the opportunity to hosts teams from around the globe would be an understatement. The excitement levels have soared through the roof.The grand entry of Indian Super League (ISL) into the state that is already filled with passionate football fans has only helped in promoting the FIFA mega-event across all regions in Kerala. Kerala’s ISL representative, Kerala Blasters have a huge fan following and they have taken matters into their own hands as far as promotions for the World Cup are concerned.For a start, the popular Kerala Blasters fan group named ‘Manjappada’ initiated flash mobs with banners across different parts of the state. Wearing yellow jerseys that represented their club colours, the fans were at their energetic best at local towns and in cities. Article continues below Editors’ Picks Why Barcelona god Messi will never be worshipped in the same way in Argentina Lyon treble & England heartbreak: The full story behind Lucy Bronze’s dramatic 2019 Liverpool v Man City is now the league’s biggest rivalry and the bitterness is growing Megan Rapinoe: Born & brilliant in the U.S.A. Arjun Ajayan, a football-crazy 23-year-old who lives a few kilometres away from the stadium in Kochi, believes that the U-17 World Cup could prove to be a stepping stone for the country and he, like the rest of Kochi, is excited about the massive event. “To be able to witness international teams like Brazil and Spain in Kochi is a dream come true. I grew up watching Brazil and we know how Ronaldinho and Toni Kroos came through the U17 ranks. This is the proudest moment for people in Kochi,” he remarked.Palakkad, Thrissur, Kasargod and Malappuram witnessed the Yellow Brigade in full flow as they danced with joy in public, in an attempt to reach out to people and get them to the stadium for the big event.There were bike rallies in Kottayam and Ernakulam districts. In Delhi, where India U-17 will play their group games, these set of fans successfully organized a promotional campaign that encouraged people to book tickets and fill the stadium to offer support for the host nation.The district of Malappuram is especially known for its love for football and there will be a huge number of Brazil supporters coming all the way to Kochi when Brazil take the field. They have set up special buses covered with posters of the Brazil team despite the absence of star player Vinicius Junior.Malappuram is more than 160 kilometres away from Kochi but that has never been a concern for the fans. Vishnu Bose, a football-loving engineer from Malappuram, feels that the chance to watch a FIFA event at the stadium is an opportunity that should be grabbed with both hands.”I have never watched a World Cup match from a stadium. Although it is the U-17 players that are taking the field, they are the stars of tomorrow. I can’t wait to watch some of the academy graduates from the club I support in Europe.”The temptation to go to the Kaloor JLN stadium to watch Brazil, Spain, DPR Korea, Niger, Guinea and Germany is inexplicably irresistible to the people of Kerala. On October 7, when Brazil meet Spain at the Kochi stadium, the city will come to a standstill and all eyes will between the two goal posts for ninety invaluable minutes.
Marcus Rashford says that he has no issues with Paul Pogba’s penalty on Monday despite the Frenchman missing from the spot as Manchester United dropped points.The Red Devils were forced to settle for a draw with Wolves on Monday at the Molineux Stadium, with Anthony Martial and Ruben Neves scoring in either half of the teams’ second Premier League match of the season.But Manchester United could have seized the lead in the second half through Pogba, who fired his spot-kick into a diving Rui Patricio as the World Cup winner opted for power over placement. Article continues below Editors’ Picks Emery out of jail – for now – as brilliant Pepe papers over Arsenal’s cracks What is Manchester United’s ownership situation and how would Kevin Glazer’s sale of shares affect the club? Ox-rated! Dream night in Genk for Liverpool ace after injury nightmare Messi a man for all Champions League seasons – but will this really be Barcelona’s? Patricio’s save was enough to seal a tough point for Wolves while earning Pogba plenty of criticism for missing his fourth penalty of the calendar year.Following the match, Ole Gunnar Solskjaer reiterated that both Pogba and Rashford have been designated as penalty takers, and the latter says he has no problem with conceding Monday’s spot-kick to the former despite the miss.”Paul wanted to take it. It’s that simple. Everybody can miss a penalty,” Rashford told Sky Sports. “He’s scored countless penalties for us and throughout his career. It’s normal to miss one. We forget about that now.”We go again in the next game and if we play how we played today, with a bit more urgency, we’ll be fine.”He added: “It’s simple. If you want to take it, you take it. I took one last week so for me it’s no problem for him to take one this week. It’s unfortunate that he didn’t score but it’s football.”Pogba’s decision to take the penalty was criticised by former Manchester United star Gary Neville, who said that he was “fuming” when he saw the midfielder step up to the spot .But Rashford backed his team-mate and said that both he and Pogba are confident from the spot, and that whoever takes the next one will have plenty of belief when the situation arises once again.”The confidence that you’re going to score the goal is always the same. And so it should be,” he said.”We practice pretty much all week and we score the majority of the time so there’s no reason why you shouldn’t have the confidence to take the penalty.”Like I say, it’s unfortunate we didn’t score it but it’s not on him it’s as a team. We take that forward into the next game.”Next up for Manchester United is a clash with Crystal Palace at Old Trafford on Saturday. Check out Goal’s Premier League 2019-20 fantasy football podcast for game tips, debate and rivalries.