Earth may be crashing through dark matter walls

Earth is constantly crashing through huge walls of dark matter, and we already have the tools to detect them. That's the conclusion of physicists who say the universe may be filled with a patchwork quilt of force fields created shortly after the big bang.

Observations of how mass clumps in space suggest that about 86 per cent of all matter is invisible dark matter, which interacts with ordinary matter mainly through gravity. The most popular theory is that dark matter is made of weakly interacting massive particles.

WIMPs should also interact with ordinary matter via the weak nuclear force, and their presence should have slight but measurable effects. However, years of searches for WIMPs have been coming up empty.

"So far nothing is found, and I feel like it's time to broaden the scope of our search," says Maxim Pospelov of the University of Victoria in Canada. "What we propose is to look for some other signatures."

Bubbly cosmos

Pospelov and colleagues have been examining a theory that at least some of the universe's dark matter is tied up in structures called domain walls, akin to the boundaries between tightly packed bubbles. The idea is that the hot early universe was full of an exotic force field that varied randomly. As the universe expanded and cooled, the field froze, leaving a patchwork of domains, each with its own distinct value for the field.

Having different fields sit next to each other requires energy to be stored within the domain walls. Mass and energy are interchangeable, so on a large scale a network of domain walls can look like concentrations of mass – that is, like dark matter, says Pospelov.

If the grid of domain walls is packed tightly enough – say, if the width of the domains is several hundred times the distance between Earth and the sun – Earth should pass through a domain wall once every few years. "As a human, you wouldn't feel a thing," says Pospelov. "You will go through the wall without noticing." But magnetometers – devices that, as the name suggests, measure magnetic fields – could detect the walls, say Pospelov and colleagues in a new study. Although the field inside a domain would not affect a magnetometer, the device would sense the change when Earth passes through a domain wall.

Dark matter walls have not been detected yet because anyone using a single magnetometer would find the readings swamped by noise, Pospelov says. "You'd never be able to say if it's because the Earth went through a bizarre magnetic field or if a grad student dropped their iPhone or something," he says.

Network needed

Finding the walls will require a network of at least five detectors spread around the world, Pospelov suggests. Colleagues in Poland and California have already built one magnetometer each and have shown that they are sensitive enough for the scheme to work.

Domain walls wouldn't account for all the dark matter in the universe, but they could explain why finding particles of the stuff has been such a challenge, says Pospelov.

If domain walls are found, the news might come as a relief to physicists still waiting for WIMPs to show up. Earlier this month, for instance, a team working with a detector in Russia that has been running for more than 24 years announced that they have yet to see any sign of these dark matter candidates.

Douglas Finkbeiner of the Harvard-Smithsonian Center for Astrophysics, who was not involved in Pospelov's study, isn't yet convinced that dark matter walls exist. But he is glad that physicists are keeping an open mind about alternatives to WIMPs.

"We've looked for WIMP dark matter in so many ways," he says. "At some point you have to ask, are we totally on the wrong track?"

Journal reference: Physical Review Letters, DOI: 10.1103/PhysRevLett.110.021803

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.

If you are having a technical problem posting a comment, please contact technical support.

Read More..

Scope to expand health screening programmes for elderly: Koh Poh Koon

SINGAPORE: The People's Action Party (PAP) candidate for the Punggol East by-election Dr Koh Poh Koon said he plans to set up a wellness centre for the elderly to help senior residents age actively.

He said there is scope to expand health screening and preventive programmes for the elderly in the ward.

Dr Koh told reporters that plans are still in early stages but the centre will be built as part of the new Community Centre, to be located near Rivervale Plaza.

He said fundraising for the new centre has reached 50 per cent.

Dr Koh added that he will push forward on this effort if and when he is elected MP for the area.

- CNA/ck

Read More..

Memorial service honors Swartz as activist, individual

Perhaps not surprisingly, one of the main threads running through today's memorial service in New York City for tech activist Aaron Swartz was a call to action.

That call arose again and again from varied speakers, and was sounded as one of the final notes of the observance when master of ceremonies Ben Wikler, a political campaigner and friend of Swartz's, announced that the service had come to an end but added, "I hope it's clear this is just the beginning of everything we have to do."

Prior to Wikler's closing remarks, Taren Stinebrickner-Kauffman -- founder of SumOfUs.org, an organization devoted to corporate accountability, and Swartz's partner at the time of his suicide, spelled out what some of that "everything" should be.

A fitting tribute to Swartz, she said, would be for "all of us to go out today and fight to make the world a better place." Specifically, Stinebrickner-Kauffman said, the U.S. Attorney's office in Massachusetts -- which at the time of Swartz's death was prosecuting him for his alleged theft of millions of documents from the Jstor database of academic articles -- must be "held accountable" for what critics have said was its persecution of Swartz.

She said the Massachusetts Institute of Technology, where Swartz accessed the database, "must be sure that it's never again complicit" in the sort of pressure put on Swartz by the government. She said the Computer Fraud and Abuse Act, a mid-1980s antihacking law, must be reformed so "this kind of power" over accused hackers could never again be handed to prosecutors. And she said the entire criminal justice system in the U.S. must be reformed in order to make it truly just.

Stinebrickner-Kauffman also said, in a remark that inspired a roar of approval from the hundreds gathered to remember Swartz -- a champion of open access to information -- that all academic research must be made freely available to everyone, everywhere.

Quinn Norton said she'd come to speak not about the "incredibly accomplished activist" or the "Internet saint," but about "a person who almost never did any of the damn dishes" and who sang to her daughter in the car.

(Credit:
Screenshot by Edward Moyer/CNET)

'Hack the whole world'
More than one appeal for action was aimed at the tech community. Doc Searls -- a fellow at the Center for Information Technology and Society at the University of California, Santa Barbara, and an alumnus fellow of the Berkman Center for Internet and Society at Harvard University -- spoke of how Swartz, a figurehead of the anti-SOPA movement, fought the system. Most geeks, he said, "tend to avoid the legal stuff.... There are so few geeks that go that extra step to protect us.... We need to do the work he started."

Roy Singham, chair of IT consultancy Thoughtworks and a major proponent of open-source software, spoke of Swartz's fear that the "wonderful world of technology" would be "usurped" and end up not being a tool of democracy. He contrasted Swartz with the heads of well-known and moneymaking tech companies, whom he called the "self-aggrandizing ego maniacs" who use technology for the benefit "of the 1 percent."

And Stinebrickner-Kauffman recalled a scene in which Swartz spoke before a group of programmers, wielding a picture of Harry Potter, snapping his fingers, and telling them that they could "do magic," that they could "make the world a better place with programming."

David Segal -- a politician, and executive director of the online organizing group Demand Progress -- said Swartz wanted to change everything: "He was trying to hack the whole world -- in the best possible way."

'Another human being'
But there was room too, among the cries for action, for reflection on Swartz's everyday humanity. Writer and photographer Quinn Norton, a former partner of Swartz's, noted that with his death, Swartz had "left us and entered the realm of mythmaking." She wanted to be sure he was remembered in a multidimensional way, as someone who neglected to do the dishes, who sang to her daughter in the
car, who "was another human being with all the flaws and glories that we all have."

At the same time, however, there seemed to be little doubt on the part of Quinn and the other speakers that the world had lost someone special. As Edward Tufte, the famous writer on information design, put it, Swartz was "marvelously and vigorously different" and there's a scarcity of that in today's world. Perhaps, Tufte said, "we can all be a little more different too."

A video of the service can be viewed on the "Remember Aaron Swartz" Web site. (As of this writing, the audio is garbled during the first few seconds of the archived video, but it quickly rights itself. At this point, too, only the first 40 minutes or so of the service are available for viewing.)

Read More..

Attack at Algeria Gas Plant Heralds New Risks for Energy Development

The siege by Islamic militants at a remote Sahara desert natural gas plant in Algeria this week signaled heightened dangers in the region for international oil companies, at a time when they have been expanding operations in Africa as one of the world's last energy frontiers. (See related story: "Pictures: Four New Offshore Drilling Frontiers.")

As BP, Norway's Statoil, Italy's Eni, and other companies evacuated personnel from Algeria, it was not immediately clear how widely the peril would spread in the wake of the hostage-taking at the sprawling In Amenas gas complex near the Libyan border.

Map by National Geographic

Algeria, the fourth-largest crude oil producer on the continent and a major exporter of natural gas and refined fuels, may not have been viewed as the most hospitable climate for foreign energy companies, but that was due to unfavorable financial terms, bureaucracy, and corruption. The energy facilities themselves appeared to be safe, with multiple layers of security provided both by the companies and by government forces, several experts said. (See related photos: "Oil States: Are They Stable? Why It Matters.")

"It is particularly striking not only because it hasn't happened before, but because it happened in Algeria, one of the stronger states in the region," says Hanan Amin-Salem, a senior manager at the industry consulting firm PFC Energy, who specializes in country risk. She noted that in the long civil war that gripped the country throughout the 1990s, there had never been an attack on Algeria's energy complex. But now, hazard has spread from weak surrounding states, as the assault on In Amenas was carried out in an apparent retaliation for a move by French forces against the Islamists who had taken over Timbuktu and other towns in neighboring Mali. (See related story: "Timbuktu Falls.")

"What you're really seeing is an intensification of the fundamental problem of weak states, and empowerment of heavily armed groups that are really well motivated and want to pursue a set of aims," said Amin-Salem. In PFC Energy's view, she says, risk has increased in Mauritania, Chad, and Niger—indeed, throughout Sahel, the belt that bisects North Africa, separating the Sahara in the north from the tropical forests further south.

On Thursday, the London-based corporate consulting firm Exclusive Analysis, which was recently acquired by the global consultancy IHS, sent an alert to clients warning that oil and gas facilities near the Libyan and Mauritanian borders and in Mauritania's Hodh Ech Chargui province were at "high risk" of attack by jihadis.

"A Hot Place to Drill"

The attack at In Amenas comes at a time of unprecedented growth for the oil industry in Africa. (See related gallery: "Pictures: The Year's Most Overlooked Energy Stories.") Forecasters expect that oil output throughout Africa will double by 2025, says Amy Myers Jaffe, executive director of the energy and sustainability program at the University of California, Davis, who has counted 20 rounds of bidding for new exploration at sites in Africa's six largest oil-producing states.

Oil and natural gas are a large part of the Algerian economy, accounting for 60 percent of government budget revenues, more than a third of GDP and more than 97 percent of its export earnings. But the nation's resources are seen as largely undeveloped, and Algeria has tried to attract new investment. Over the past year, the government has sought to reform the law to boost foreign companies' interests in their investments, although those efforts have foundered.

Technology has been one of the factors driving the opening up of Africa to deeper energy exploration. Offshore and deepwater drilling success in the Gulf of Mexico and Brazil led to prospecting now under way offshore in Ghana, Mozambique, and elsewhere. (See related story: "New Oil—And a Huge Challenge—for Ghana.") Jaffe says the Houston-based company Anadarko Petroleum has sought to transfer its success in "subsalt seismic" exploration technology, surveying reserves hidden beneath the hard salt layer at the bottom of the sea, to the equally challenging seismic exploration beneath the sands of the Sahara in Algeria, where it now has three oil and gas operations.

Africa also is seen as one of the few remaining oil-rich regions of the world where foreign oil companies can obtain production-sharing agreements with governments, contracts that allow them a share of the revenue from the barrels they produce, instead of more limited service contracts for work performed.

"You now have the technology to tap the resources more effectively, and the fiscal terms are going to be more attractive than elsewhere—you put these things together and it's been a hot place to drill," says Jaffe, who doesn't see the energy industry's interest in Africa waning, despite the increased terrorism risk. "What I think will happen in some of these countries is that the companies are going to reveal new securities systems and procedures they have to keep workers safe," she says. "I don't think they will abandon these countries."

This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

Read More..

Algeria Hostage Crisis Over, One American Dead

After the Algerian military's final assault on terrorists holding hostages at a gas complex, the four-day hostage crisis is over, but apparently with additional loss of life among the foreign hostages.

One American, Fred Buttaccio of Texas, has been confirmed dead by the U.S. State Department. Two more U.S. hostages remain unaccounted for, with growing concern among U.S. officials that they did not survive.

But another American, Mark Cobb of Corpus Christi, Texas is now confirmed as safe. Sources close to his family say Cobb, who is a senior manager of the facility, is safe and reportedly sent a text message " I'm alive."

Inside Algerian Hostage Crisis, One American Dead Watch Video

American Hostages Escape From Algeria Terrorists Watch Video

In a statement, President Obama said, "Today, the thoughts and prayers of the American people are with the families of all those who were killed and injured in the terrorist attack in Algeria. The blame for this tragedy rests with the terrorists who carried it out, and the United States condemns their actions in the strongest possible terms. ... This attack is another reminder of the threat posed by al Qaeda and other violent extremist groups in North Africa."

According to Algerian state media, 32 militants are dead and a total of 23 hostages perished during the four-day siege of the In Amenas facility in the Sahara. The Algerian Interior Ministry also says 107 foreign nationals who worked at the facility for BP and other firms were rescued or escaped from the al Qaeda-linked terrorists who took over the BP joint venture facility on Wednesday.

The Japanese government says it fears "very grave" news, with multiple casualties among the 10 Japanese citizens working at the In Amenas gas plant.

Five British nationals and one U.K. resident are either deceased or unaccounted for in the country, according to British Foreign Minister William Hague. Hague also said that the Algerians have reported that they are still trying to clear boobytraps from the site.

Read More..

NASA planet-hunter is injured and resting

Lisa Grossman, physical sciences reporter

(Image: NASA/Kepler mission/Wendy Stenzel)

NASA's planet-hunting Kepler telescope has put its search for alien Earths on hold while it rests a stressed reaction wheel.

The injured wheel normally helps to control the telescope's orientation, keeping it pointed continuously at the same patch of sky. Kepler stares at the thousands of stars in its field of view to watch for the telltale blinks that occur when a planet crosses in front of its star. It has found nearly 3000 potential planets outside our solar system since its launch in 2009, transforming the field of exoplanet research and raising hopes of someday finding alien life.

When it launched, Kepler had four reaction wheels: three to control its motion along each axis, and one spare. But last July, one wheel stopped turning. If the spacecraft loses a second wheel, the mission is over.

So when another wheel started showing signs of elevated friction on 7 January, the team decided to play it safe. After rotating the spacecraft failed to fix the problem, NASA announced yesterday that they're placing Kepler in safe mode for 10 days to give the wheel a chance to recover.

The hope is that the lubricating oil that helps the wheel's ball bearings run smoothly around a track will redistribute itself during the rest period.

The telescope can't take any science data while in safe mode. But if the wheel recovers on its own, Kepler's extended mission will run until 2016, leaving it plenty of time to make up for the lost days.

"Kepler is a statistical mission," says Charlie Sobeck, Kepler's deputy project manager at NASA's Ames Research Centre in Mountain View, California. "In the long run, as long as we make the observations, it doesn't matter a lot when we make the observations."

Despite the high stakes, the team doesn't seem too worried.

"Each wheel has its own personality, and this particular wheel has been something of a free spirit," Sobeck says. "It's had elevated torques throughout the mission. This one is typical to what we've seen in the past, and if we had four good wheels we probably wouldn't have taken any action."

"I prefer to picture the spacecraft lounging at the shore of the cosmic ocean sipping a Mai Tai so that she'll be refreshed and rejuvenated for more discoveries," wrote Kepler co-investigator Natalie Batalha in an email.

The team will check up on the wheel on 27 January and return to doing science as soon as possible.

There are two exoplanet missions currently being considered for after Kepler is finished, says Doug Hudgins at NASA Headquarters in Washington, DC. One, TESS (Terrestrial Exoplanet Survey Satellite), would scan the entire sky for planets transiting the stars nearest to the sun. The other, FINESSE (Fast Infrared Exoplanet Spectroscopy Survey Explorer), would take spectra of planets as they passed in front of their stars as a way to probe their atmospheres.

The missions are being evaluated now, and NASA will probably select one this spring, Hudgins says. The winner will launch in 2017.

If Kepler goes down with its reaction wheel, that won't affect which mission wins, he adds. "That's a straight-up competition based on the merits of the two concept study reports."

Read More..

SDA will "make use of new technology" to reach out to residents

SINGAPORE: The Singapore Democratic Alliance (SDA) will not be holding an on site rally for the Punggol East by-election on Sunday.

The Party's candidate Desmond Lim said the party will "make use of new technology" to reach out to residents.

This will likely to be in the form an online rally which will be streamed.

Mr Lim was speaking to the media on the sidelines of a visit to the Arulmigu Velmurugan Gnanamuneeswarar Temple at Rivervale Crescent.

He said cost was an important factor in the decision, made unanimously by party members.

He said running an election is costly, and the party is small, with limited resources.

Mr Lim said using new media will also reach out to Punggol East residents, many of whom are younger and are more tech-savvy.

He added the party would release details of this arrangement "very soon".

Mr Lim added that the decision was not because the party could not get their rally application approved.

- CNA/ck

Read More..

Crave Ep. 105: How to clip your nails in space

This week on Crave, we're back with a look at all the Cravey stuff we spotted at CES 2013. Plus, Canadian astronaut Christopher Hadfield teaches us the safest way to clip our nails in outer space, and the Hal 9000 computer replica from Think Geek refuses to cooperate.

January 18, 2013 8:05 PM PST

Read More..

Attack at Algeria Gas Plant Heralds New Risks for Energy Development

The siege by Islamic militants at a remote Sahara desert natural gas plant in Algeria this week signaled heightened dangers in the region for international oil companies, at a time when they have been expanding operations in Africa as one of the world's last energy frontiers. (See related story: "Pictures: Four New Offshore Drilling Frontiers.")

As BP, Norway's Statoil, Italy's Eni, and other companies evacuated personnel from Algeria, it was not immediately clear how widely the peril would spread in the wake of the hostage-taking at the sprawling In Amenas gas complex near the Libyan border.

Map by National Geographic

Algeria, the fourth-largest crude oil producer on the continent and a major exporter of natural gas and refined fuels, may not have been viewed as the most hospitable climate for foreign energy companies, but that was due to unfavorable financial terms, bureaucracy, and corruption. The energy facilities themselves appeared to be safe, with multiple layers of security provided both by the companies and by government forces, several experts said. (See related photos: "Oil States: Are They Stable? Why It Matters.")

"It is particularly striking not only because it hasn't happened before, but because it happened in Algeria, one of the stronger states in the region," says Hanan Amin-Salem, a senior manager at the industry consulting firm PFC Energy, who specializes in country risk. She noted that in the long civil war that gripped the country throughout the 1990s, there had never been an attack on Algeria's energy complex. But now, hazard has spread from weak surrounding states, as the assault on In Amenas was carried out in an apparent retaliation for a move by French forces against the Islamists who had taken over Timbuktu and other towns in neighboring Mali. (See related story: "Timbuktu Falls.")

"What you're really seeing is an intensification of the fundamental problem of weak states, and empowerment of heavily armed groups that are really well motivated and want to pursue a set of aims," said Amin-Salem. In PFC Energy's view, she says, risk has increased in Mauritania, Chad, and Niger—indeed, throughout Sahel, the belt that bisects North Africa, separating the Sahara in the north from the tropical forests further south.

On Thursday, the London-based corporate consulting firm Exclusive Analysis, which was recently acquired by the global consultancy IHS, sent an alert to clients warning that oil and gas facilities near the Libyan and Mauritanian borders and in Mauritania's Hodh Ech Chargui province were at "high risk" of attack by jihadis.

"A Hot Place to Drill"

The attack at In Amenas comes at a time of unprecedented growth for the oil industry in Africa. (See related gallery: "Pictures: The Year's Most Overlooked Energy Stories.") Forecasters expect that oil output throughout Africa will double by 2025, says Amy Myers Jaffe, executive director of the energy and sustainability program at the University of California, Davis, who has counted 20 rounds of bidding for new exploration at sites in Africa's six largest oil-producing states.

Oil and natural gas are a large part of the Algerian economy, accounting for 60 percent of government budget revenues, more than a third of GDP and more than 97 percent of its export earnings. But the nation's resources are seen as largely undeveloped, and Algeria has tried to attract new investment. Over the past year, the government has sought to reform the law to boost foreign companies' interests in their investments, although those efforts have foundered.

Technology has been one of the factors driving the opening up of Africa to deeper energy exploration. Offshore and deepwater drilling success in the Gulf of Mexico and Brazil led to prospecting now under way offshore in Ghana, Mozambique, and elsewhere. (See related story: "New Oil—And a Huge Challenge—for Ghana.") Jaffe says the Houston-based company Anadarko Petroleum has sought to transfer its success in "subsalt seismic" exploration technology, surveying reserves hidden beneath the hard salt layer at the bottom of the sea, to the equally challenging seismic exploration beneath the sands of the Sahara in Algeria, where it now has three oil and gas operations.

Africa also is seen as one of the few remaining oil-rich regions of the world where foreign oil companies can obtain production-sharing agreements with governments, contracts that allow them a share of the revenue from the barrels they produce, instead of more limited service contracts for work performed.

"You now have the technology to tap the resources more effectively, and the fiscal terms are going to be more attractive than elsewhere—you put these things together and it's been a hot place to drill," says Jaffe, who doesn't see the energy industry's interest in Africa waning, despite the increased terrorism risk. "What I think will happen in some of these countries is that the companies are going to reveal new securities systems and procedures they have to keep workers safe," she says. "I don't think they will abandon these countries."

This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

Read More..

Armstrong Tearful Over Telling Kids Truth

Lance Armstrong, 41, began to cry today as he described finding out his son Luke, 13, was publicly defending him from accusations that he doped during his cycling career.

Armstrong said that he knew, at that moment, that he would have to publicly admit to taking performance-enhancing drugs and having oxygen-boosting blood transfusions when competing in the Tour de France. He made those admissions to Oprah Winfrey in a two-part interview airing Thursday and tonight.

"When this all really started, I saw my son defending me, and saying, 'That's not true. What you're saying about my dad? That's not true,'" Armstrong said, tearing up during the second installment of his interview tonight. "And it almost goes to this question of, 'Why now?'

"That's when I knew I had to talk," Armstrong said. "He never asked me. He never said, 'Dad, is this true?' He trusted me."

He told Winfrey that he sat down with his children over the holidays to come clean about his drug use.

"I said, 'Listen, there's been a lot of questions about your dad, about my career and whether I doped or did not dope,'" he said he told them. "'I always denied that. I've always been ruthless and defiant about that, which is why you defended me, which makes it even sicker' I said, 'I want you to know that it's true.'"

He added that his mother was "a wreck" over the scandal.

Armstrong said that the lowest point in his fall from grace and the top of the cycling world came when his cancer charity, Livestrong, asked him to consider stepping down.

George Burns/Harpo Studios, Inc.

Lance Armstrong-Winfrey Interview: How Honest Was He? Watch Video

Lance Armstrong-Winfrey Interview: Doping Confession Watch Video

After the U.S. Anti-Doping Agency alleged in October that Armstrong doped throughout his reign as Tour de France champion, Armstrong said, his major sponsors -- including Nike, Anheuser Busch and Trek -- called one by one to end their endorsement contracts with him.

"Everybody out," he said. "Still not the most humbling moment."

Then came the call from Livestrong, the charity he founded at age 25 when he was diagnosed with testicular cancer.

"The story was getting out of control, which was my worst nightmare," he said. "I had this place in my mind that they would all leave. The one I didn't think would leave was the foundation.

"That was most humbling moment," he said.

Armstrong first stepped down as chairman of the board for the charity before being asked to end his association with the charity entirely. Livestrong is now run independently of Armstrong.

"I don't think it was 'We need you to step down,' but, 'We need you to consider stepping down for yourself,'" he said, recounting the call. "I had to think about that a lot. None of my kids, none of my friends have said, 'You're out,' and the foundation was like my sixth child. To make that decision, to step aside, that was big."

In Thursday's interview installment, the seven-time winner of the Tour de France admitted publicly for the first time that he doped throughout his career, confirming after months of angry denials the findings of the U.S. Anti-Doping Agency, which stripped him of his titles in October.

He told Winfrey that he was taking the opportunity to confess to everything he had done wrong, including for years angrily denying claims that he had doped.

READ MORE: Armstrong Admits to Doping

WATCH: Armstrong's Many Denials Caught on Tape

READ MORE: 10 Scandalous Public Confessions

Read More..