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Scientists propose a new type of dark matter and how we can

first_imgA simulation of dark matter filaments across the universe.  Zarija Lukic/Lawrence Berkeley National Laboratory Dark matter is an enigmatic beast. We can’t see it, yet we know it makes up most of our universe. Finding the mysterious particle (or particles) the exotic matter is composed of has puzzled and intrigued scientists for decades. On June 6 at the Planck 2019 conference, an international meeting highlighting frontier physics research, John Terning and Christopher Verhaaren, theoretical physicists at the University of California, Davis, presented a new theory for what makes up dark matter and how we might detect it. A preprint paper of their study was uploaded to the arXiv directory on May 31. Dark matter and dark energy, two theoretical forms of matter, are thought to make up more than 85% of the known universe. When we look out into space, the evidence for the existence of dark matter is plentiful — we can see the effect it has on gravity and the expansion of the universe. We know something, an invisible particle perhaps, is lurking out of sight and responsible for the way our universe works. Scientists have long struggled to find the elusive, exotic particle that makes up dark matter, and more theories abound every year. In December, an Oxford scientist proposed that the universe was made up of a dark fluid. Others have suggested hunting for dark matter in cutting-edge new ways. Still, we have failed to detect it.Which brings us to Terning and Verhaaren’s idea. They argue for a new “type” of dark matter and a way to detect it, a one-two punch of theory and experimental validation. However, the authors of the study caution that verifying it could take quite some time. The new type of dark matter is different from previous theories, which suggest the exotic, invisible particles may be made up of weakling interacting massive particles, or WIMPs. No experiments have been able to find these particles, though scientists have built large, shielded laboratories that hope to reveal them. “We still don’t know what dark matter is,” said Terning in a press release. “The primary candidate for a long time was the WIMP, but it looks like that’s almost completely ruled out.”   The private rocket company trying to send Australia to… See SLAC, a two-mile particle accelerator next to Stanford 2 3:17 Share your voice Commentscenter_img The researchers looked at an opposing theory for dark matter with an equally fantastical name: “dark electromagnetism.” It says there’s a subatomic particle known as a dark photon which sometimes interacts with regular photons that we can already detect. The duo added their own spin to the idea by showing dark matter might be caused by “dark monopoles,” which are based on quantum theory.It all gets very tangled here, especially for us mere mortals struggling with everyday physics. The bottom line? We’ve got a new theory which proposes the “dark monopole” could be detected in an experiment thanks to its interactions with regular photons and the Aharonov-Bohm effect, which has been proven experimentally. However, the observable effect would be incredibly small — even smaller than gravitational waves — and we don’t yet have the technology to detect such minute signals right now. Alan Duffy, a dark matter researcher at Swinburne University in Australia, notes how the first detection of gravitational waves (itself only a theory until recently) took “a century of heroic scientific and engineering effort” suggesting that might be “a worry for the testability of the [new] prediction.”Where does that leave Terning and Verhaaren’s theory? Well, as a theory, of course. But that’s where all good science starts. Tags 33 Photos Now playing: Watch this: Sci-Techlast_img read more

Smart card distribution in Rangpur from 7 Oct

first_imgSmart card. File photoThe distribution of machine-readable smart national identity (NID) cards will begin in Rangpur City Corporation (RCC) area on 7 October.Election Commissioner (EC) Mahbub Talukdar will inaugurate the distribution at Rangpur district council community centre at 11:00am, Communication Officer of the EC secretariat, NID Wing Ashiqur Rahman told BSS on Tuesday.Acting secretary of the EC secretariat Helaluddin Ahmed and RCC mayor Sarfuddin Ahmad will take part in the function, said Rahman.To facilitate the voters with any information related to NID, the NID wing of the EC has launched a help desk, he said, adding that voters can know update of their NID by calling to 105 from any telecom operator.Voters can also know about the date and place of their smart card distribution through sending SMS from any mobile operator. One needs to text-SCNID17-digit national ID> — to 105 to know about his or her date and place.last_img read more

Robbers hack policeman in Habiganj

first_imgMap of HabiganjA sub-inspector of police sustained stab injury in an attack of robbers on Chatiain-Ratanpur road in Madhabpur upazila of Habiganj on Monday night, reports news agency UNB.The injured is Zia Uddin, sub-inspector of Chatiain police outpost.S M Raju Ahmed, senior assistant superintendent of police, said a gang of robber attacked Zia around 10:00 pm while he was returning to police outpost from his workplace and stabbed him, leaving critically injured.Later, the injured SI was admitted to Habiganj Sadar Hospital.last_img

Smart Tools for Listing Products

first_img 5 min read This hands-on workshop will give you the tools to authentically connect with an increasingly skeptical online audience. Opinions expressed by Entrepreneur contributors are their own. After collecting ’60s music and memorabilia for threedecades, René Klaassen is using eBay to turn all thosememories into money. Key to his efforts are market research toolsthat help him determine what’s likely to sell and for how much,what the best dates and times are to list certain items, and othervaluable information.Case in point: a Pink Floyd 45 rpm record he recently decided topart with. “I didn’t know what to expect,” saysKlaassen of Los Angeles. “I was hoping for something in thehundred-dollar range.” Typing “Pink Floyd” into amarket analysis tool from Terapeak revealed to Klaassen that Sundaylistings did better than Tuesday listings, listing an item at 10a.m. beat listing it at 5 p.m., and 10-day auction-style listingsfared better than those lasting only seven days.Klaassen (eBay User ID: heineken) fine-tuned his listingaccordingly. The result: He sold the record for $285.”It’s quite nifty,” Klaassen says of hismarket-research capabilities. “Rather than just grabbing an LPor 45 off the shelf [to sell], I immediately go to Terapeak andlook for sales history.”Similar market research tools, both from eBay itself and fromthird parties that license data on sales closed on eBay, can helpmany businesses on eBay outperform expectations. Victoria, BritishColumbia-based Terapeak starts with data licensed from eBay andallows sellers and buyers to conduct research such as looking backat completed items over extended periods of time to find pricetrends for specific products. “If you sell Nike Air Jordans oneBay, you can go to www.terapeak.com, type in ‘Nike Air Jordans,’and find out how they have been doing [over] the past 30days,” says Dave Popowich, Terapeak’s marketingcoordinator. The online subscription service costs $16.95 per monthand provides trend data going back as far as a year in somecases.HammerTap’s DeepAnalysis market research software runs on auser’s own PC. For $17.95 monthly or a $179.95 annual licensefee, HammerTap can do a number of powerful analyses, suchas studying how starting prices relate to bids and determiningwhich category is best for an item based on the number of bids orselling prices in different categories, says Jen Cano, director ofPR at the Orem, Utah, company.Other popular research tools come from ándale, a MountainView, California, company whose products help eBay sellers identifywhat’s been hot in the past six weeks, determine prevailingselling prices, count the number of sellers of specific items andmore. ándale’s $7.95 per month Research tool even givesusers recommendations on such crucial criteria as the price,category, day and time for a given listing.The new kid on the block is eBayMarketplace Research. John Bodine, eBay product marketingmanager, says, “Marketplace Research can help you understandsales and price trends within categories, as well as provideinsight into new products you may wish to source andsell.”Specifically, Marketplace Research provides consolidated metricson up to 90 days of completed listings. That’s a considerableimprovement over the previously available eBay completed listingsinformation, which only showed 15 days’ worth of data.Marketplace Research allows for more sophisticated analyses oflong-term data. Users can, for instance, see how completed listingsof collectibles related to the Chicago White Sox Major LeagueBaseball team rose steadily until the end of the 2005 World Series,then, following the White Sox victory, fell sharply. Those kinds ofinsights can help a seller decide whether to sell White Sox-relatedproducts now.Marketplace Research is priced in three tiers. Fast Pass isdesigned for the casual user, who will pay $2.99 for two days’worth of unlimited access to the subscription services. Fast Passusers can tap into 60 days of historical data and see an item’saverage sold price, sold price range, average Buy It Now price, BuyIt Now price range, last sold price, number of completed items andother metrics. Basic level, at $9.99 monthly, offers additionalmetrics, such as information on an item’s start price range,number of successful sales and average shipping costs. Both theFast Pass and Basic packages allow users to save up to 10 searches.At $24.99 a month, Pro level allows users to search 90 days ofhistorical data, save up to 100 searches and research internationaldata. It also includes more charting options and advanced filters.All three provide information on the top searches performed bybuyers on the site.The world of market research on eBay has come a long way in ashort time, and it’s still evolving. One significant limitationis time. For example, eBay Marketplace Research is initiallylimiting its data to 90 days, Bodine says, in part because of themassive computing power required to analyze millions of dailylistings over a long period. However, given the annual cycles onwhich many businesses live and die, year-long market trends are ofvital interest.Even with their limitations, market research tools are wellworth the cost to most sellers, who find that using them oftenresults in faster sales at higher prices. “Prior to Terapeak,I didn’t have a way of seeing what the market could bear,”says Klaassen.That cuts both ways, Bodine notes: Market research makes eBaymore useful for both vendors and purchasers. “Research beforeyou buy,” he says, “and research before yousell.”Mark Henricks writes on business andtechnology for leading publications and is author of Not Just a Living. Enroll Now for Free March 24, 2006 Free Workshop | August 28: Get Better Engagement and Build Trust With Customers Nowlast_img read more