Quantum skyfall puts Einstein's gravity to the test

DIVIDING a falling cloud of frozen atoms sounds like an exotic weather experiment. In fact, it's the latest way to probe whether tiny objects obey Einstein's theory of general relativity, our leading explanation for gravity.

General relativity is based on the equivalence principle, which says that in free fall, all objects fall at the same rate, whatever their mass, provided the only force at work is gravity. That has been proven for large objects: legend has it that Galileo did it first by dropping various balls from the Tower of Pisa. Whether equivalence holds at quantum scales, where gravity's effects are not well understood, isn't clear. Figuring it out could help create a quantum theory of gravity, one of the biggest goals of modern physics.

Creating a quantum equivalent of Galileo's test isn't easy. In 2010 a team led by Ernst Rasel of the University of Hannover in Germany monitored a quantum object in free fall, by tossing a Bose-Einstein condensate (BEC) – a cloud of chilled atoms that behaves as a single quantum object and so is both particle and wave – down a 110-metre tall tower. Now they have split and recombined the wave – all before the BEC, made of rubidium atoms, reached the bottom. This produces an interference pattern that records the path of the falling atoms and can be used to calculate their acceleration (Physical Review Letters, doi.org/km6). The next step is to do the same experiment on a different kind of atom, with a different mass, to see if the equivalence principle holds.

The BEC can only be split for 100 milliseconds in the tower before hitting the bottom, so to allow tiny differences between the atom types to emerge, the work must be repeated in space, where the waves can be split for longer. By showing that a matter-wave can be split and recombined while falling, Rasel's result is a "major step" towards the space version, says Charles Wang of the University of Aberdeen, UK.

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Asian markets rise on Wall St rally, ECB comments

HONG KONG: Asian markets rose Thursday after the Dow on Wall Street hit a more than five-year high, while the head of the European Central Bank soothed concerns over the eurozone.

A strong bond sale in Italy also helped the euro despite uncertainty after weekend polls, while the yen resumed its downward trend after Japan's government nominated a fan of aggressive easing as the new central bank governor.

Tokyo climbed 2.04 per cent as the yen sank on confirmation that Japan's government had put forward Haruhiko Kuroda to take over at the Bank of Japan.

Kuroda, the current Asian Development Bank chief, is known as an advocate of a looser monetary policy to overcome slow growth, in line with the views of Prime Minister Shinzo Abe.

The dollar bought 92.44 yen, compared with 92.16 yen in New York late Wednesday.

Hong Kong shares advanced 1.10 per cent, Sydney added 0.71 per cent, Seoul rose 1.02 per cent and Shanghai was up 0.39 per cent.

ECB President Mario Draghi said Wednesday the bank would preserve the integrity of the eurozone, reasserting its commitment to buy up bonds of under-pressure countries.

"We are committed to preserving the integrity of our currency, in the interests of all people of the euro area," he said.

The announcement, which came after US Federal Reserve Chairman Ben Bernanke said its own huge easing would stay in place, came as welcome relief to markets after Italy's poll deadlock raised fears of a return to Europe's debt crisis.

On forex markets the euro rebounded after being hammered in the wake of Sunday's inconclusive poll, which saw voters shun austerity policies and leave the country with a hung parliament.

The euro sat at $1.3150 and 121.56 yen in Tokyo, from $1.3136 and 121.07 yen -- and well up from the levels just above $1.30 and 119 yen seen earlier in the week.

The single currency was also given support from news that Rome had successfully sold 6.5 billion euros of treasury bonds, albeit at a higher price, providing evidence for now that it can borrow cash to pay its own bills.

On Wall Street the Dow ended at its highest level since October 2007 after reports showed US pending home sales rebounded sharply in January to the highest level in almost three years.

In other positive news, durable goods orders in January -- excluding volatile aircraft -- surged 1.9 per cent, with gains particularly strong in capital goods, suggesting business confidence in the economy in upcoming months.

The Dow jumped 1.26 per cent, while the S&P 500 rose 1.27 per cent and the Nasdaq added 1.04 per cent.

Oil prices rose, with New York's main contract, light sweet crude for delivery in April, gaining 34 cents to $93.10 a barrel and Brent North Sea crude for April delivery adding 35 cents to $112.22.

Gold was at $1,597.70 at 0220 GMT compared with $1,608.32 late Wednesday.

- AFP/ck

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Supreme Court divided on Voting Rights Act

(CBS News) WASHINGTON -- The Voting Rights Act has been the law of the land for nearly half a century, helping to ensure that minorities are not denied the right to vote. On Wednesday, Shelby County, Ala., challenged the law at the Supreme Court.

The arguments sharply divided the justices: The court's conservative majority appeared poised to strike down at least part of the act and eliminate the current federal oversight of voting in the South.

At issue is a decades-old provision in the law that requires nine states, mostly in the South, to get approval from the federal government before changing voting laws or procedures.

Justice Antonin Scalia called it a "racial entitlement."

Chief Justice John Roberts asked if the government believed "the citizens in the South are more racist than citizens in the North." Roberts said current data on voter turnout revealed more problems in Massachusetts than in Mississippi.

Congress did not rely on current data when, in 2006, it reauthorized the Voting Rights Act. It continued to rely on rates of minority voter registration and turnout in the elections of 1964, 1968 and 1972.

Will the Voting Rights Act survive the Supreme Court?
Proposed changes to Voting Rights Act stir controversy in Alabama

Alabama attorney Frank Ellis said Congress should look at the modern-day South.

Frank Ellis

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CBS News

"We ask for some recognition that we and these other converted jurisdictions have made great strides over the last 48 years," Ellis said.

The liberal justices strongly defended the law, saying Congress had thousands of pages of evidence documenting discrimination.

"Discrimination is discrimination, and what Congress said is it continues," Justice Sonia Sotomayor said.

Justice Stephen Breyer said, "The disease is still there ... it's gotten a lot better, a lot better, but it's still there."

Debo Adegbile

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CBS News

That's why civil rights attorney Debo Adegbile said the provision is as necessary today as a generation ago.

"The problems are much more serious, much more repetitive, there is a much greater continuity in certain places than others," Adegbile said.

The liberal justices -- and the Obama administration -- say the court should defer to Congress, which they say is was better situated to make judgments about discrimination in voting. But based on the arguments today, it does appear a majority of the conservative judges are ready to tell Congress it's going to have to make some changes in that law.

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Holder Says Sequester Makes America Less Safe

The looming budget sequestration will make Americans less safe, Eric Holder says—and anyone who says otherwise isn't telling the truth.

"This is something that is going to have an impact on the safety of this country," the U.S. attorney general told ABC's Pierre Thomas on Wednesday in a wide-ranging, exclusive interview.

"And anybody that says otherwise is either lying or saying something that runs contrary to the facts," Holder said.

In his interview with ABC News, Holder reiterated warnings that if automatic spending cuts are triggered on Friday, the Justice Department will be handicapped in some of its most vital missions to prevent terrorist attacks and crime.

"The Justice Department is going to lose nine percent of its budget between now and September 30th. We're going to lose $1.6 billion. There are not going to be as many FBI agents, ATF agents, DEA agents, prosecutors who are going to be able to do their jobs," Holder said. "They're going to be furloughed. They're going to spend time out of their offices, not doing their jobs."

Portions of the interview will air Wednesday, February 27 on "ABC World News"

Patrick Semansky/AP Photo

Eric Holder Says Homegrown Terror Threat Equals International: Exclusive Watch Video

Eric Holder Remembers Newtown, His Worst Day on the Job: Exclusive Watch Video

President Obama's Cabinet members have been warning for weeks that budget sequestration, which will begin Friday unless Obama and Republicans reach a deficit-reduction deal to avoid it, will leave their agencies shorthanded and could bring about disastrous consequences. Homeland Security Secretary Janet Napolitano and Transportation Secretary Ray LaHood have both appeared at the White House press briefing room to warn that furloughs for border-patrol agents, TSA agents and air-traffic controllers will mean weakened border and port security, longer waits in airport security lines, and logjammed air travel.

Holder, for his part, warned in a Feb. 1 letter to the Senate Appropriations Committee that cuts to the FBI, the ATF, the U.S. Marshals Service, and U.S. Attorneys would limit the department's capacity to investigate crimes. Cuts at the Bureau of Prisons, Holder wrote, would mean lockdowns and potential violence, with fewer staff members on hand. In a separate letter, FBI Director Robert Mueller warned that counterterrorism operations would be affected, with the possible elimination of some joint terrorism task forces with state and local police. Limited surveillance and slower response times would mean unwatched targets and the possibility that individuals on terrorism watch lists could gain entry to the U.S.

"FBI's ability to proactively penetrate and disrupt terrorist plans and groups prior to an attack would be impacted," Mueller wrote.

To Holder, the problem is simple.

"If you don't have prosecutors and agents doing what we expect them to do, and we won't if this thing actually takes place, we are going to be a nation that is going to be less safe. And that is simple fact," Holder said.

Some Republicans have claimed the Obama administration is exaggerating the sequester's purported consequences as a ploy to campaign for tax hikes. On "Fox News Sunday" this week, Sen. Tom Coburn, R-Okla., posited that federal agencies enjoy enough flexibility to avoid the worst consequences of the cuts.

On Wednesday, Holder acknowledged that the Justice Department will do what it can to avoid compromised security, while maintaining that furloughs can't be avoided.

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Newly spotted comet to buzz Mars in 2014

Lisa Grossman, physical sciences reporter

A Martian sunset, as seen by NASA's Spirit rover in 2005.
(Image: Mars Exploration Rover Mission, Texas A&M, Cornell, JPL, NASA)

There's a new comet in town, and it is making a beeline for Mars. If projections of its orbit are correct, the icy visitor will buzz the Red Planet in October 2014.

Dubbed C/2013 A1, the comet was discovered on 3 January by prolific comet hunter Robert McNaught at Siding Spring Observatory in New South Wales, Australia. Colleagues at the Catalina Sky Survey in Arizona found images of the comet in their catalogue that date back to 8 December 2012, giving additional information about its movements.

These observations allowed astronomers to trace the comet's likely path around the sun. The calculated trajectory has C/2013 A1 crossing Mars' orbit on 19 October 2014, according to Australian blogger Ian Musgrave.

That doesn't necessarily mean a collision will occur. The best estimates right now have the comet passing a safe distance of 900,000 kilometres from the Martian surface. Asteroid 2012 DA14 got much closer to Earth last week, skimming by at a distance of 34,400 kilometres. But with so little data in hand, the calculations are not precise. It's possible the comet will miss Mars by as much as 36 million kilometres - or it could smack right into the planet. "An impact can't be ruled out at this stage," Musgrave wrote.

From Earth, we should be able to see the comet and Mars sitting side by side through small telescopes. And from Mars, the comet could be as spectacular as the expected "supercomet" ISON, which will come into view this year and could outshine the full moon.

Assuming the comet's orbit brings it close enough - but not too close - to Mars, the object should be visible either by rovers on the surface or the armada of Mars-orbiting satellites, which have a history of snapping spectacular shots of the Red Planet and its neighborhood.

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Asian markets up on Fed stand, strong yen hits Tokyo

HONG KONG: Asian markets mostly rose on Wednesday after US Federal Reserve head Ben Bernanke reaffirmed the central bank's huge monetary easing scheme, but a stronger yen sent Tokyo lower.

Investors remained hesitant and the euro came under pressure after Italy's election results which left no party in overall control, raising concerns that uncertainty in Rome could see the eurozone return to the dark days of crisis.

Tokyo fell 0.78 per cent by noon but Hong Kong rose 0.44 per cent, Sydney added 0.64 per cent, Shanghai climbed 1.14 per cent and Seoul was 0.18 per cent higher.

In testimony to Congress Bernanke said the Fed's $85 billion a month bond-purchase programme aimed at holding down long-term interest rates and encouraging investment -- known as quantitative easing -- was still merited.

While warning that looming steep budget cuts could slow growth, he stressed high unemployment was a main challenge to the economy, adding that the risks of the programme -- inflation, and risky behaviour in the financial industry -- were being monitored closely.

Bernanke said the programme was "providing important support to the recovery".

His comments on Tuesday were a relief for financial markets, which stumbled last week after minutes from the Fed's latest policy meeting suggested some members wanted to curtail the policy before the economy was back in track.

"Bernanke confirmed the Fed's commitment to continue quantitative easing until unemployment falls, and US economic data are clearly improving," Martin Lakos, division director in Macquarie's Private Wealth division in Australia, told Dow Jones Newswires.

On Wall Street the Dow rose 0.84 per cent, the S&P 500 added 0.61 per cent and the Nasdaq jumped 0.43 per cent.

US investors also took comfort in surprisingly robust new home sales while the Conference Board's February consumer confidence index showed a surprise jump to 69.6 from 58.4 in January, well above the average analyst estimate of 62.0.

But the dollar fell against the yen in Asia as dealers sought the safe havens after the inconclusive Italian elections.

The dollar bought 91.70 yen in Tokyo Wednesday, from 91.93 yen in New York late Tuesday and well off the 94.77 yen high seen on Monday.

The euro slipped to $1.3043 and 119.60 yen from $1.3061 and 120.08 yen.

Eurozone fears have been reignited after the Italian polls, which left the country with a hung parliament and a protest party effectively holding the balance of power.

Investors fear the outcome will mean Italy will reverse the austerity policies put in place to pay off its debts, with implications for the wider region.

Italian leftist leader Pier Luigi Bersani, who said he had "come first but not won", warned that the huge anti-austerity protest vote should be heeded beyond Italy's borders, adding: "The bell tolls also for Europe."

Oil prices were mixed, with New York's main contract, light sweet crude for delivery in April, shedding two cents to $92.61 while Brent North Sea crude for April delivery gained three cents to $112.74.

Gold was at $1,612.40 at 0220 GMT compared with $1,597.80 late Tuesday.

- AFP/ck

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Doomed balloon riders nearly landed, then shot upward

STORY HIGHLIGHTS

• NEW: Conflicting reports emerge over company's safety record


• A British passenger and the pilot are hospitalized


• The balloon carried tourists from the UK, Hong Kong, Japan, France and Hungary


• A gas explosion caused the balloon to fall about 300 meters (almost 1,000 feet)

Were you there? Have you taken such a trip before in Egypt? Send us your experiences.

(CNN) -- The view from above southern Egypt is stunning, a contrast of beige desert valley giving way to green farmland, including fields of sugar cane. Tourists soak in the sight by hiring hot air balloons that have large baskets to carry passengers hundreds of feet above the countryside.

Tuesday morning, as one of the balloons prepared to land, an explosion pierced the air, followed by a spreading billow of smoke.

"My first thought was that it was sugar cane that was burning," said Christopher Michel, a photographer who was a passenger in another balloon at the time.

Smoke from the burning sugar cane painted the ancient city of Luxor below with an eerie haziness.

But the concern shown by the balloon pilot and the blaring sirens from emergency vehicles told Michel that something was wrong. He could not imagine the extent: One of the balloons had exploded, and its 21 passengers and operators plummeted about 1,000 feet (300 meters) to the ground.

By Tuesday afternoon, the number of dead had climbed to 19, making it the world's deadliest hot air balloon accident in at least 20 years.

"This juxtaposition of this great beauty and this wonderful country and this horrible tragedy is just really shocking," Michel told CNN. "We all feel terrible."

It was an early, dark morning, Michel said, and uneventful for 45 minutes until they started to descend. He was overlooking mud-brick buildings and fields, with the Valley of the Kings in the distance, when the explosion shattered the quiet of the morning.

It was a gas explosion, state-run EgyNews reported.

Fatal hot air balloon crash

HIDE CAPTION

Passengers in the balloon included 19 foreign tourists: nine from Hong Kong, four from Japan, three from Britain, two from France and one from Hungary, officials said.

An Egyptian pilot and another Egyptian also were on board, Luxor province spokesman Badawi al-Masri said.

Two people -- a Briton and the pilot -- are hospitalized.

Balloon rides offering panoramic aerial views of the Nile River and the ancient temples of Karnak and Hatshepsut are a popular tourist attraction in Luxor, about a nine-hour drive southeast of Cairo.

"You can see Valley of the Kings in the background bordered by farmland," Pauline Liang of Vancouver, Canada, told CNN's iReport last year. "Below were banana farms, and behind us was the city of Luxor. There was a great contrast between desert landscape, lush farmland and urban development."

Tuesday's crash prompted Gov. Izzat Saad of Luxor province to ban all hot air balloon flights until further notice.

Conflicting reports emerged about the company that operated the doomed balloon, Sky Cruise.

The head of the country's civil aviation authority said the company was licensed and working legally, EgyNews reported.

The agency has begun an investigation of the incident, Mohammed Ibrahim Sharif said.

According to Sharif, a fire broke out in the balloon while the workers were trying to land it, just feet from the ground. The balloon then shot upwards again, he said.

The balloon's basket was divided into four parts, he said, each holding five passengers.

Meanwhile, Luxor's chamber of tourism said the company had previous violations, EgyNews reported.

Several balloon companies had terminated contracts with the local meteorological service after the Egyptian revolution, Tharwat Agami, chairman of the chamber of tourism, said.

Sky Cruise and other companies were known to violate safety and security instructions by flying out of East Luxor, instead of the recommended West Luxor, he said.

Comparing it to a previous hot air balloon experience in another country, Michel noted that there was no safety briefing before the Luxor balloons lifted off the ground, but added that he felt safe during the trip.

From what he could tell, the doomed balloon was not overloaded, he said on his Twitter account.

Luxor is among Egypt's top tourist draws. Visitors go to see ancient temples and tombs, and travel sites often recommend the hot air balloon trips.

The last hot air balloon accident in Luxor occurred in 2009, when 16 foreign tourists were injured after a balloon struck a cell phone transmission tower.

Until Tuesday's incident, the deadliest accident in recent memory took place in 1989, when 13 people were killed as two hot air balloons collided in Australia.

Egyptian government spokesman Alaa Hadidi announced that the Cabinet will form a committee from the Ministry of Civil Aviation to investigate Tuesday's accident, EgyNews said.

CNN's Housam Ahmed and Hamdi Alkhshali, along with journalist Adam Makary in Cairo, contributed to this report.

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Debate over Voting Rights Act changes in Ala.

(CBS News) -- On Wednesday, the Supreme Court will hear a challenge to the landmark Voting Rights Act of 1965. Both sides agree the south have changed in the past half-century. At issue is, has it changed enough?

In Shelby County, Alabama, the question is whether the state's racist past must forever define it.

(Watch: Voting Rights Act challengers take aim at "Section 5", below)

Fifty years ago, Alabama was the cradle of the civil rights movement, where protestors endured fire hoses, arrests and bombings in the fight for equality. One result was the Voting Rights Act.

One provision of the Act, Section 5, still requires all or part of 16 states, mostly in the south, to get approval from the Justice Department before changing voting procedures or electoral maps.

"Section five, which is what we are attacking, was never intended by congress to be permanent," said Frank Ellis, a Shelby County lawyer who is at the center of the battle to eliminate Section 5, and force the federal government to treat Alabama and other covered states like the rest of the country.

"They are still using the same criteria to determine whether these 16 states that are covered, they are still using the same test that they used in 1965," Ellis said.

"Things have changed in the South," he said. "This is a dynamic society."

But Ernest Montgomery says things have not changed enough. He was on the city council in Calera, Alabama when city officials, facing a population boom, redrew his district map. He lost the election to a white candidate. Under Section 5, the Justice Department ordered a new election and Montgomery won.

The minority representation in his district under the old map was about 67% African American, according to Montgomery. With the new map, that number dropped to about 28%.

Voting Rights Act faces Supreme Court challenge

Voting Rights Act Section 5 "not the only tool" to protect voting rights, Obama says

VIDEO: SCOTUS to hear challenge to Voting Rights Act

Shelby County Pastor Harry Jones calls it discrimination.

"I think it was designed to dilute the power of the minority community," Jones said. "It did just that."

Opponents like Ellis say they are not attacking the entire Voting Rights Act. If there's intentional discrimination, people can sue, just like they do in Michigan, Ohio and other states that aren't by Section Five.

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Senate Votes to Confirm Hagel as Defense Secretary

After a tough two-month battle characterized by tough interrogation and a partisan divide, the Senate voted 58-41 to confirm Chuck Hagel -- President Obama's nominee -- as secretary of defense this afternoon.

Only four Republicans broke party lines to vote in Hagel's favor. They included Sens. Thad Cochran of Mississippi, Richard Shelby of Alabama, Mike Johanns of Nebraska and Rand Paul of Kentucky, though Paul had voted against moving forward with the vote earlier today.

Before that cloture vote to close the debate and bring Hagel's nomination to a vote, Senate Majority Leader Harry Reid, D-Nev., warned Republicans against continuing their partisan fight against the nominee.

"Senate Republicans have delayed for the better part of two weeks for one reason: partisanship," Reid said. "Politically motivated delays send a terrible signal to allies around the world, and they send a terrible signal to tens of thousands of Americans serving in Afghanistan, other parts of world and those valiant people who are serving here in the United States. For the sake of national security, it's time to set aside this partisanship."

The measure to move forward passed by a vote of 71-27. It needed at least 60 votes to pass.

Some Republican senators took the time before the vote to take a last stab at Hagel.

John Cornyn, R-Texas, who was one of 15 senators who sent a letter to Obama last week calling for him to withdraw his nomination of Hagel, said Hagel had proved that he's ill-prepared to assume the defense secretary post.

Chuck Hagel as Secretary of Defense: Confirmation Process Watch Video

Obama Taps Sen. Chuck Hagel for Defense Secretary Watch Video

"There's simply no way to sugar coat it," Cornyn said. "Sen. Hagel's performance before the Senate Armed Services Committee was remarkably inept, and we should not be installing a defense secretary who is obviously not qualified for the job and who holds dangerously misguided views on some of the most important issues facing national security policy for our country. Sen. Hagel is clearly the wrong man for the job."

The Senate returned today after a week off from debating Hagel's pros and cons.

Today's was not the first attempt to bring Hagel's nomination to the floor.

Republicans blocked a cloture vote to confirm Hagel on Valentine's Day, pushing the decision back until after their President's Day recess.

Democrats framed that rejection as a filibuster, while Republicans said they needed another week to discuss the candidate's record.

"This is a very controversial nominee. There is a desire to not end debate now," Sen. Lindsey Graham, R-S.C., said that Thursday. "We feel like come back next week, after the break, unless there is some bombshell I'd be ready to move on to vote."

Ten days later, GOP Sens. Tom Coburn of Oklahoma and John McCain of Arizona predicted the Senate would go through with a vote today.

A group of 15 Republicans sent a letter to Obama last week asking him to withdraw Hagel's nomination. Coburn, one of the senators who signed that letter, said the fight among lawmakers over Hagel's qualifications would weaken him should he become secretary.

"I like Chuck Hagel as an individual, but the fact is, in modern times, we haven't had one defense secretary that's had more than three votes against him," Coburn said on "Fox News Sunday" this weekend. "And you're going to have 40 votes against him, or 35 votes. And that sends a signal to our allies as well as our foes that he does not have broad support in the U.S. Congress, which limits his ability to carry out his job."

McCain did not sign that letter.

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