Today on New Scientist: 11 January 2013

Largest structure challenges Einstein's smooth cosmos

One-twentieth the diameter of the observable universe, a group of galaxies dents the cherished idea that the cosmos is uniform at large scales

Straitjacket drug halts herpes virus's escape stunt

Herpes infections recur as the virus is adept at evading our defences, but a new drug that suppresses enzymes exploited by the virus seems effective

Zoologger: Mouse eats scorpions and howls at the moon

Super-aggressive grasshopper mice are not put off by the deadly venom of the scorpions they feast on - in fact, nothing much seems to scare them

Sand tsunami pictured striking Australian coast

The spectacular wall of sand and dust appears to block out the sun like a giant wave

Astrophile: Zombie stars feed on Earth-like exoplanets

We can now learn what planets around other stars are made of - by looking at the atmospheres of white dwarfs that have swallowed up their worlds

Life will find a way, even in the midst of a hurricane

Not for the faint-hearted: to sample the microbiome of a hurricane, fly a jetliner through it

Physics not biology may be key to beating cancer

Billions of dollars spent on cancer research have yielded no great breakthrough yet. There are other ways to attack the problem, says physicist Paul Davies

Feedback: Return of nominative determinism

The last nominative determinism stories, salads of gizzards and his chestnuts, Australian graduates in outer space, and more

A comeback for virtual reality? Inside the Oculus Rift

The Oculus Rift promises an immersive gaming experience like no other. Niall Firth gets his head in the game and gives it a try

Is the US facing Flu-maggedon?

The US flu season has come early this winter, leaving many hospitals overwhelmed. But is the situation really any worse than usual?

Your body's insights into life and cosmos

The Universe Within by Neil Shubin tells stories from your body about our species, planet and universe. PLUS: a cautionary tale of inspirational scientists

Hands on with Leap Motion's gestural interface

The makers of the ultra-precise gestural interface talk big about killing off the mouse. But it looks like more than just bluster

Personal assistant for your emails streamlines your life

GmailValet aims to use crowdsourcing to give everyone a personal assistant to help deal with their emails - it could cost as little as $2 a day

DNA 'identichip' gives a detailed picture of a suspect

A new microchip-based DNA tester can identify multiple traits of an individual at a time, even where their DNA is scarce

Most fundamental clock ever could redefine kilogram

Physicists have created the first clock with a tick that depends on the hyper-regular frequency of matter itself

Nanomachine mimics nature's protein factory

An artificial ribosome that assembles proteins and peptides could make it much easier to manufacture antibiotics and exotic new materials

Muscle mimic pulls electricity from wet surface

A plastic film that repeatedly curls up and flips over when wet could power devices in remote areas or sensors embedded in sweaty clothing

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Rockefeller to retire from US Senate

WASHINGTON: Veteran Democrat Jay Rockefeller of West Virginia announced Friday that he will not seek re-election to the US Senate next year, providing Republicans a prime opportunity to pick up a seat.

The lawmaker has been a longtime defender of the rights of laborers and the poor, and was an initial supporter of using US military force against the regime of Iraq's Saddam Hussein before becoming a fierce critic of US president George W. Bush and his war policies.

"As I approach 50 years of public service in West Virginia, I've decided that 2014 will be the right moment for me to find new ways to fight for the causes I believe in," Rockefeller said in a statement released as he spoke to supporters and media in state capital, Charleston.

"Championing those most in need has been my life's calling, and I will never stop fighting to make a difference for the people who mean so much to me."

Rockefeller, 75, a two-term West Virginia governor, was first elected to the Senate in 1984.

He is a great-grandson of oil tycoon John Rockefeller, and the only Democrat in the Republican family dynasty to serve in national politics.

Rockefeller is chairman of the Senate Committee on Commerce, Science and Transportation, where he said he has led "exhilarating fights... to make our cars more efficient, our phone bills more truthful, our Coast Guard more agile, and the Internet more safe."

He also served as chairman of the powerful Senate Intelligence Committee in the wake of the terror attacks of September 11, 2001 and helped implement reform of the intelligence community.

President Barack Obama lauded Rockefeller's "lifetime of service" and said his fellow Democrat would be missed on Capitol Hill.

"From his time in the state legislature to the governor's office to the Senate floor, Jay has built an impressive legacy, one that can be found in the children who have better schools, the miners who have safer working conditions (and) the seniors who have retired with greater dignity," Obama said in a statement.

Rockefeller stressed that he would not shy away from the challenges facing lawmakers in the next two years, notably a looming series of fiscal battles.

"We've got a really rough debt ceiling in several weeks coming up," he said, referring to the debate over extending US borrowing authority. "I want to be part of that fight."

Rockefeller's departure sets up a succession scramble, with Republicans eager to chip away at the Democrats' 55-45 hold of the 100-seat Senate.

House Republican Shelley Capito has announced in November that she would run for Rockefeller's seat in 2014.

Since his first Senate victory Rockefeller has mostly coasted to re-election, but with Obama deeply unpopular in West Virginia, no one doubts the difficulty the senator would have faced in winning a sixth term.

West Virginia, among the poorest states in the nation, voted Democratic in presidential elections from 1988 to 1996, but from 2000 onward it has been reliably Republican.

Although a West Virginia Republican has not served in the Senate since 1958, Capito has cited the recent political shift as a sign that Republicans now have a strong shot.

Congressman Nick Rahall, a 19-term Democrat, hailed Rockefeller as a lawmaker who "pledged his heart, mind and strength" to West Virginians ever since he first went to the state as an anti-poverty worker in the early 1960s.

-AFP/ac

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John McAfee brings his `Where's Waldo' act to Portland

A photo of software founder of John McAfee on Dec. 12, 2012. McAfee was released from detention in Guatemala and was scheduled to fly to the U.S.

(Credit:
CBS News)

Last time we checked, John McAfee was on the lam from -- well, whoever it was that he said was after him in Belize. But the former software mogul, who was deported to the United States after fleeing to Guatemala, has decided to pitch his tent in Portland for a while. (Assuming, of course, that he's not yanking the media's chain for kicks and giggles.)

Willamette Week snagged an interview with McAfee who said he was "looking for a home here and plans to live Portland for the next year and a half while he collaborates with local artist Chad Essley on a graphic novel about his life."

"I like the weather. I don't like the sun," he told his interviewer. "This is perfect. I've got enough sun for a while. I had five years of everyday sunny..Nothing wrong with rain, rain is good...it cleans the streets. It makes for a new ambiance, a little bit darker. I'm in a darker mood these days.

In November Police in Belize searched for McAfee, one of the pioneers of antivirus software, for questioning about the murder of his neighbor, American expat Gregory Faull. That began a month-long case of hide-and-seek as McAfee went on the lam from the authorities, all the while telling his story to a transfixed media that he was being wrongfully persecuted by officials in Belize and that he feared for his life if was arrested.

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Biggest Thing in Universe Found—Defies Scientific Theory

Talk about a whopper—astronomers have discovered a structure in the universe so large that modern cosmological theory says it should not exist, a new study says. (Also see "Giant 'Blob' Is Largest Thing in Universe [2006].")

Using data from the Sloan Digital Sky Survey, an international team of researchers has discovered a record-breaking cluster of quasars—young active galaxies—stretching 4 billion light-years across.

"This discovery was very much a surprise, since it does break the cosmological record as the largest structure in the known universe," said study leader Roger Clowes, an astronomer at University of Central Lancashire in England.

For comparison, our own galaxy, the Milky Way, is just a hundred thousand light-years across, while the local supercluster of galaxies in which it's located, the Virgo Cluster, is only a hundred million light-years wide.

Giant Quasar a Head-Scratcher

Astronomers have known for years that quasars can form immense clusters that stretch to more than 700 million light-years across, said Clowes. But the epic size of this group of 73 quasars, sitting about 9 billion light-years away, has left them scratching their heads.

That's because current astrophysical models appear to show that the upper size limit for cosmic structures should be no more than 1.2 billion light years.

"So this represents a challenge to our current understanding and now creates a mystery—rather than solves one," Clowes said. (Also see "Dark Galaxies Discovered—May Be Cosmic 'Missing Links.'")

The titanic structure, known simply as the Large Quasar Group (LQG), also appears to break the rules of a widely accepted cosmological principle, which  says that the universe would look pretty much uniform when observed at the largest scales.

"It could mean that our mathematical description of the universe has been oversimplified-and that would represent a serious difficulty and a serious increase in complexity," Clowes said.

Decoding Early-Galaxy Evolution

Significant not only for its record-breaking size, the massive structure could possibly shed light on the evolution of galaxies like our own Milky Way. Quasars, which pump out powerful jets of energy, are among the brightest and most energetic objects from when the universe was still young. They represent an early, but brief, stage in the evolution of most galaxies. (See "Earliest Known Galaxies Spied in Deep Hubble Picture.")

One theory holds that this type of colossal collection of quasars may be precursors to galaxy superclusters in the modern universe—but the exact nature of their connection is still a mystery.

The discovery, a prime target for computer modeling, also needs to be mapped out more thoroughly with telescopes, said Gerard Williger, an astronomer at the University of Louisville in Kentucky not connected with the study.

"This structure is bigger than we expect based on the shockwaves formed in the universe after the big bang," said Williger.

"There is very likely some mechanism [that] is turning on quasars over a large scale like this—and in a short time—which could relate to some condition in the early universe."

Th quasar study was published this week in the Monthly Notices of the Royal Astronomical Society.

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Poisoned Lottery Winner's Exhumation Approved

A judge has approved the exhumation of the Chicago lottery winner who died of cyanide poisoning.

Judge Susan Coleman of the Probate Division of the Cook County Circuit Court in Illinois today approved the county medical examiner's request to exhume the body of Urooj Khan at Rosehill Cemetery in Chicago.

Khan, 46, died July 20, 2012, from what was initially believed to be natural causes. But a family member whose identity has yet to be revealed asked the medical examiner's office to re-examine the cause of death, which was subsequently determined to be cyanide poisoning.

The office did so by retesting fluid samples that had been taken from Khan's body, including tests for cyanide and strychnine.

In explaining the request for exhumation, Chief Medical Examiner Stephen Cina has said, "If or when this goes to court, it would be nice to have all the data possible."

The Chicago businessman had won a $1 million lottery jackpot -- before taxes -- the month before he died.

In Photos: Biggest Lotto Winners

In the latest legal twist, Khan's brother filed a petition Wednesday to a judge asking Citibank to release information about Khan's assets to "ultimately ensure" that [Khan's] minor daughter "receives her proper share." Khan reportedly did not have a will.

He left behind a widow, Shabana Ansari, 32, and a teenage daughter from his first marriage. Ansari and Khan reportedly married 12 years ago in India.

Authorities questioned Ansari in November and searched the home she shared with Khan. She and her attorney, Al Haroon Husain, say she had nothing to do with his death.

"It's sad that I lost my husband," she told ABC News. "I love him and I miss him. That's all I can say."

The siblings of the poisoned lottery winner have pursued legal action to protect their niece's share of her late father's estate. They also questioned whether he and Ansari were legally married, but Ansari's attorney said she has a marriage certificate from India that is valid in the United States.

ImTiaz Khan, 56, Khan's brother, and Meraj Khan, 37, their sister, had won a court order to freeze the lottery winnings after Ansari cashed the check.

Husain said Ansari cashed the lottery check after it was mailed to the home, which she did not request.

The lottery check, about $425,000 in cash, was issued July 19 by the Illinois Comptroller's Office, then mailed, according to Brad Hahn, spokesman for the Comptroller's Office. Hahn said it was cashed Aug. 15, nearly a month after Khan's death, but he did not know who cashed it.

The judge later approved Ansari's competing claim as an administrator of the estate.

"I don't care what they talk [sic]," Ansari told ABC News of what her in-laws are saying.

Ansari said she was married to Khan but declined to comment to ABC News about cashing the check after his death, although The Associated Press has reported that she denied removing any of the assets.

Meraj Khan filed in September to become the legal guardian of her niece. After the judge asked the 17-year old daughter with whom she wished to live, she chose her aunt and has been there since November, Husain said.

Neither sibling has petitioned to obtain a share of the dead man's estate, which is estimated to be $1.2 million in lottery winnings, real estate, Khan's laundry business and automobiles.

Neither the attorney for ImTiaz Khan nor the two siblings has responded to requests for comment.

A status hearing on the future of the estate is scheduled for Jan. 24, according to the AP.

ABC News' Alex Perez and Matthew Jaffe contributed to this report.

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Muscle mimic pulls electricity from wet surface

Electricity has been squeezed from a damp surface for the first time, thanks to a polymer film that curls up and moves – a bit like an artificial muscle – when exposed to moisture. The film could be used to run small, wearable devices on nothing but sweat, or in remote locations where conventional electricity sources aren't available.

When a dry polymer absorbs water, its molecular structure changes. This can, in principle, be converted into larger-scale movement, and in turn electricity. But previous attempts at creating a material powered by a moisture gradient – the difference in chemical potential energy between a wet region and a dry region - failed to produce a useful level of force.

These unsuccessful tries used a polymer called polypyrrole. Now Robert Langer and colleagues at the Massachusetts Institute of Technology have turned to the material again, embedding chains of it within another material, polyol-borate. This more complex arrangement mimics structures found in muscles as well as in plant tissues that bend in response to changes in humidity.

Flipping film

The result looks like an ordinary piece of thin black plastic, but when placed on a wet surface, something extraordinary happens. As the material absorbs water, its end curls away from the surface and the film becomes unstable, so it flips over. The ends have now dried out, so they are ready to absorb more water, and the whole process repeats itself. This continuous flipping motion lets the film travel across a suitably moist surface unaided.

Langer found that a 0.03-millimetre-thick strip, weighing roughly 25 milligrams, could curl up and lift a load 380 times its mass to a height of 2 millimetres. It was also able to move sideways when carrying a load about 10 times its mass.

To extract energy from this effect, Langer's team added a layer of piezoelectric material – one which produces electricity when squeezed. When this enhanced film, weighing about 100 milligrams, flipped over, it generated an output of 5.6 nanowatts – enough to power a microchip in sleep mode.

Electricity from sweat

Though the output is small, it is proof that electricity can be extracted from a water gradient. "To the extent of our knowledge, we are the first to utilise a water gradient, without a pressure gradient, to generate electricity," says Langer.

Large-scale energy harvesting is unlikely as the size of the device needed would be impractical, but it could be used to power small devices such as environmental monitoring systems in remote locations. "It will be interesting for applications where the amount of energy needed may be low but where access to energy may be difficult," says Peter Fratzl at the Max-Planck Institute of Colloids and Interfaces in Potsdam, Germany, who was not involved in the work.

Another application, Langer suggests, would be to place the film inside the clothing of joggers or athletes. The evaporation of sweat could generate enough electricity to power sensors monitoring blood pressure and heart rate.

Journal reference: Science, DOI 10.1126/science.1230262

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US focused on Syria's chemical arms after Assad: Panetta

WASHINGTON: The United States is increasingly focused on how to secure Syria's chemical weapons if President Bashar al-Assad falls from power but is not considering sending ground troops into the war-torn country, Defense Secretary Leon Panetta said Thursday.

While the US government has issued stern warnings to Damascus against resorting to such arms in its war with rebel forces, Panetta said that a more likely scenario might be a chaotic vacuum if Assad is toppled, with uncertainty over who controls the lethal weapons.

"I think the greater concern right now is what steps does the international community take to make sure that when Assad comes down, that there is a process and procedure to make sure we get our hands on securing those sites," Panetta told a news conference. "That I think is the greater challenge right now."

The US government was discussing the issue with Israel and other countries in the region, he said, but ruled out deploying American ground forces in a "hostile" setting.

"We're not talking about ground troops," Panetta added.

The US military's top officer, General Martin Dempsey, told the same news conference that if Assad chose to use his chemical stockpiles against opposition forces, it would be virtually impossible to stop him.

Preventing the launch of chemical weapons "would be almost unachievable... because you would have to have such clarity of intelligence, you know, persistent surveillance, you would have to actually see it before it happened," he said. "And that's unlikely, to be sure."

He said that clearly worded warnings to Assad from President Barack Obama have served as a deterrent.

Even if the regime chooses not to employ the weapons, the Obama administration worries that Islamist militants allied with rebel forces might gain control of some chemical sites.

Syria's chemical weapons stockpile, which dates back to the 1970s, is the biggest in the Middle East, but its precise scope remains unclear, according to analysts.

The country has hundreds of tons of various chemical agents, including sarin and VX nerve agents, as well as older blistering agents such as mustard gas, dispersed in dozens of manufacturing and storage sites, experts say.

But it remains unclear if the chemical weapons are mounted and ready to be launched on Scud missiles, if the chemical agents are maintained effectively, and whether the regime is able to replenish its chemical stocks.

Damascus has said it might use its chemical weapons if attacked by outsiders, although not against its own people.

Panetta's comments came as prospects for international diplomacy to halt the violence in Syria appeared bleak.

The regime blasted the UN-Arab League envoy, Lakhdar Brahimi, a day before he was due to hold talks with US and Russian officials, accusing him of "flagrant bias."

The 21-month civil war has claimed more than 60,000 lives, according to the United Nations.

- AFP/jc

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The 3D sensor that could change our mobile lives

PrimeSense's 3D sensor, Capri is designed for mobile devices

(Credit:
Paul Sloan)

LAS VEGAS -- When the company behind the gesture technology in the Kinect came to CES a year ago to show how its 3D sensors can enable people to control their TVs with simple gestures, its execs talked about how their sensors eventually would be embedded in mobile devices, opening up a range of possible applications.

At CES 2013, that company, Israeli-based PrimeSense, showed off the tiny sensor it says will soon make that a reality.

PrimeSense's new 3D sensor, called Capri, is 10 times smaller than its current sensor and, according to the company, the smallest in the world. The design, says PrimeSense, allows for improved capabilities that it says will soon find its way into PCs,
tablets, laptops, phones, various robots and much more.

PrimeSense president and founder Aviad Maizels told me that the company is delivering these sensors to device makers in the coming months -- he wouldn't name which ones -- and that a bevy of small consumer products should come embedded with Capri in 2014.

Now that you, the consumer, would be aware of it. When PrimeSense's technology is in works, the user should have no clue what's making it happen. "Our partners are the ones making the applications interesting," said Maizels. "What we want is the end user to feel magic, and we will see magically things happen."

Matterport's 3D scanner

(Credit:
Matterport)

I met up Maizels at a hotel suite where PrimeSense had demos set up with several partners, each of which are putting current PrimeSense sensors to work in impressive ways. One lets you turn any surface into a touch screen; another, called Matterport, has built a 3D scanner so customers can create, say, precise 3D renderings of a building or home in minutes; it all connects via the cloud so you can see the images on a tablet or computer. For now, the device is large -- appealing mainly to insurance companies and realtors. But all this will get smaller.

PrimeSense, of course, isn't alone in the this movement towards touchless control. My colleague, Daniel Terdiman, wrote about several companies here at CES -- including PointGrab and Elliptic Labs -- that are creating ways to incorporate touchless gestures on mobile devices, including the
iPad.

The tech behind it all is different, however -- PointGrab uses a 2D camera, for instance -- and it'll be curious to see what applications evolve. Maizels wouldn't tell me what the device makers are envisioning for when they incorporate Capri into their smart phones. But he said to think about applications that involving the rear-facing camera. That could mean, among other things, ways to capture 3D movies from your phone.

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How "Cheating" Slime Mold Escapes Death

Cheaters do prosper—at least if you're a slime mold, a new study says.

The slime mold Dictyostelium discoideum, found in most warm parts of the world, has an unusual life cycle. Most of the time Dicytostelium cells are "happy" single cells that hang out and eat bacteria, according to study leader Lorenzo Santorelli of the University of Oxford, who conducted the research while at Rice University and Baylor College of Medicine.

But sometimes, when food is scarce, different strains of Dictyostelium, including a mutated strain, form a mobile, multicellular organism called a "slug." This cluster then sprouts a stalk called a fruiting body, which produces spores that disperse into new slime molds. (Also see "Slime Has Memory but No Brain.")

For a slug to produce a stalk, however, nearly 20 percent of its cells must die—essentially sacrificing themselves to pass on their genes. (Get a genetics overview.) The remaining 80 percent live on and become spores.

Now, for the first time, Santorelli and colleagues have figured out the mechanism by which the mutated strain is able to survive in higher numbers than the others.

It suppresses normal cells from becoming spores, thereby forcing more of these cells to sacrifice themselves for the stalk and die. Meanwhile, more cells in the mutated strain become spores—and thus avoid dying as stalk cells. In other words, more than the "fair share" of cheater cells see another day.

Cheating Cells Surprisingly Healthy

To make the discovery, the team mixed the cheater strain with normal strains and observed that more cells in the cheater strain live on. (See "Smart Slime, Ovulating Strippers Among 2008 Ig Nobels.")

On one hand, this isn't all that surprising, Santorelli noted: "Cooperation is always under attack in any organism—trying to get something for [yourself], it's just nature."

But what is striking, he said, is that usually cheaters eventually cause the entire cooperative system to collapse. Not so in Dictyostelium—somehow it's evolved a way to keep everything running smoothly, said Santorelli, whose study was recently published in the journal BMC Evolutionary Biology.

What's more, cheaters are usually weaker than cooperative individuals. But not in Dictyostelium cheaters, which appear to be quite healthy.

Santorelli wants to find out how the cheater strain is so successful. And, just maybe, the lowly slime mold could unravel the evolutionary and genetic basis for cooperation, he added.

"Slime mold is an amazing organism."

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Jodi Arias' Lies Detailed at Murder Trial

The jury in the Jodi Arias murder trial watched a television interview today in which Arias said "no jury will convict me" for killing her ex-boyfriend, Travis Alexander.

Arias also said she could never imagine commiting such a violent act as killing Alexander.

"I understand all the evidence is really compelling," she said in the interview. "In a nutshell, two people came in and killed Travis. I've never even shot a gun. That's heinous. I can't imagine slitting anyone's throat."

She went on to tell the interviewer, "No jury will convict me and you can mark my words on that... I am innocent."

Arias made the statements to the television show Inside Edition after she was indicted for murdering Alexander. Months later, she would confess to killing him in his Mesa, Ariz., home and say it was in self-defense.

Jodi Arias Trial: Watch Live

Jodi Arias Murder Trial: Full Coverage

Photos of Key Players and Evidence in the Jodi Arias Murder Trial

The tape was played on the fifth day of testimony in Arias's trial, in which police allege that she carried out the murder with such brutal force that she stabbed Alexander 27 times, slashed his throat from ear to ear, and shot him in the head.

Arias, now 32, claims Alexander was a controlling and abusive "sexual deviant" who she was forced to kill in self-defense.

She could face the death penalty if convicted of Alexander's murder.

Jodi Arias Trial: Jurors See Photos of Bloody Handprint Watch Video

Jodi Arias Murder Trial: Who Is the Alleged Killer? Watch Video

Jodi Arias Trial: Defense Claims Victim Was Sex Deviant Watch Video

The jury also watched as dozens of photos of blood-spattered walls, flooring, stained carpets and blood smeared sink were explained in detail by a forensic analyst from the Mesa police department, who noted that on many of the stains, water had been mixed with the blood and diluted it.

The prosecution alleges that Arias tried to wash away the evidence of the killing with water.

Prosecutors spent much of today and Wednesday using Arias' recorded statements and other testimony to prove that she lied about her relationship with Alexander, where she was when Alexander was killed, and even where she worked as a bartender.

The testimony today showed that Arias had lied to her new boyfriend Ryan Burns about working at a bar called Margaritaville in her hometown of Yreka, Calif.

"Is there any restaurant in Yreka called Margaritaville? Has there ever been?" prosecutor Juan Martinez asked Nathaniel Mendes, a former detective with the Siskiyou County Sheriff's Office in California.

"No, sir," Mendes replied.

Mendes testified that Arias worked at a restaurant called Casa Ramos in Yreka, not a Margaritaville bar that she told Burns. Mendes also went over receipts showing that Arias rented a car the day before she killed Alexander, and noted that she went to a rental outfit 90 miles from her hometown despite two businesses that rented cars in Yreka.

Arias told friends and investigators that she rented a car to go on a road trip to visit Burns, in West Jordan, Utah, on June 3, 2008. She showed up to Burns' house a day late with cuts on her hands, but told Burns that she got lost driving and that the cuts were from broken glass at her Margaritaville bar tending job, according to Burn's testimony Wednesday.

The trail of receipts showed that Arias drove from California to Alexander's hometown of Mesa on Tuesday, June 4, 2008.

There, the pair had sex and took sexually graphic photos of one another, according to photographs and the opening statement of Arias' lawyer. Shortly after the tryst, Arias killed Alexander, both sides agree.

Burns testified that Arias never mentioned going to Alexander's house when she arrived at his home in Utah. He said he did not know that Arias and Alexander were still sexually involved, and that she told him they had broken up.

When she arrived at his home, just 24 hours after killing Alexander, she seemed "normal," he said. The pair kissed and cuddled, and went out with Burns' friends, where she laughed and made conversation.

Prosecutors have also played recorded phone conversations between detectives and Arias in the weeks after Alexander's body was found. She can be heard lying multiple times to investigators as they ask about the last time she spoke with Alexander and her trip to Utah.

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