One-Minute Physics: Are unknowns part of the universe?

Sandrine Ceurstemont, editor, New Scientist TV

What's part of the universe? You may think of it as incorporating everything that exists - both on Earth and in space - but could it also include the unknown?

In this One-Minute Physics episode, film-maker Henry Reich delves into the notion of the universe as described by physics, distinguishing between the whole universe and what's observable. He looks at the three components of the universe that we are sure of and whether mathematics could be included or not. Then there is the concept of parallel universes that could extend our understanding of space.

If you enjoyed this post, check out our previous animations, to find out, for example, if space is infinite
or why mass has a split personality.

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Football: Celta Vigo replace coach Herrera with Abel Resino

MADRID: Spanish Liga outfit Celta Vigo have fired head coach Paco Herrera and replaced him with Abel Resino, the relegation-threatened club announced on Monday.

"Celta Vigo have signed Abel Resino as first team coach. He will replace Paco Herrera on the bench." read a statement on the club website.

Herrera guided the team back into the top flight last season but has seen results slide during this campaign as the team sit 18th in La Liga and four points from safety with just five wins from 24 matches.

The team who have never won the Spanish title, lost their last outing 3-1 at Getafe on Saturday which was enough for club management to bring down the axe on Herrera's reign.

Resino who was a former goalkeeper with Atletico Madrid and helped the capital club to Spanish Cups in 1991 and 1992 before coaching the team for a brief spell in 2009 and leading them to qualification for the Champions League.

The 53-year-old has also had spells at Valladolid, Granada and Valladolid.

"The new coach will be presented tomorrow (Tuesday) after first team training," continued the statement.

-AFP/ac

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What are Quantum Dots, and how could they help your next TV?

At CES in January, Sony announced several LCD TVs with "Triluminos," a new backlighting method that they promise offered "rich, authentic color, and excellent red and green reproduction." Digging deeper, it turns out Triluminos includes an optical component produced by QD Vision, Inc. called "Color IQ" which uses quantum dots to help create light.

OK, so what are quantum dots?

Quantum dots are a "semiconductor nanocrystal technology." If you remember your high school (college?) physics, avail yourself of the Wiki page.

If you don't know your valence bands from your conduction bands, you can think of a quantum dot as this: tiny pieces of matter with unique properties, including the ability to emit light at very specific wavelengths. Sort of like microscopic pieces of glitter that glow green, red, or blue depending on their size.

Red, green, and blue spectra for red, green, and blue quantum dots.

(Credit:
QD Vision)

Specific wavelengths of light are good. We need specific wavelengths of light, the more specific the better. All televisions create an image by combining the three additive primary colors: red, green, and blue (RGB). Sharp adds yellow, a secondary color, but this isn't in any content and is created by the TV. Mixing RGB in varying amounts gives us all the colors possible in our current TV system.

All LCDs create these colors with filters. Plasma displays create them with phosphors that glow in the required color (similar to the way CRT tube TVs worked). OLED, depending on the company, is one or the other. LG's method creates a "white" OLED then adds color filters. Samsung's method has specific red, green, and blue OLED sub-pixels.

So where do quantum dots come in? Sony has a method.

Sony's X900 and W900 lines
Three of Sony's 2013 TVs will use quantum dots in their backlighting, in the guise of QD Vision's Color IQ tech (the 65X900, 55X900, and 55W900). A traditional LED LCD uses blue LEDs, coated with a yellow phosphor, to create "white" light. While reasonably efficient compared to other technologies (i.e. CCFL LCDs and plasmas), this still creates a lot of "wasted" energy. Orange, for example, doesn't make it past the color filters on the front of the TV (instead, red and green are combined to create orange).

Triluminos uses blue LEDs, but instead of coating them with a yellow phosphor, the blue light from the LEDs passes through the Color IQ optical element containing red and green quantum dots. So the blue LEDs have two functions: create blue light, but also energize red- and green-emitting quantum dots so they in turn can create red and green light. About two-thirds of the light created by the blue LEDs is used to excite the QDs. Cool, right?

This diagram is a top-down view of one side of two edge-lit LCDs (the front is "up" in this case, the back is "down"). The upper image shows a traditional "white" LED (blue, with yellow phosphor). The lower image is the method used in Sony's Triluminos: a blue LED that passes through red and green quantum dots. This RGB light bounces off the light guide, and out through the liquid crystal and other layers just like a regular LCD TV.

(Credit:
QD Vision)

If you're curious about how LCD backlighting works, check out Is LCD and LED LCD HDTV uniformity a problem? which has images and diagrams of how backlights work. Oh, and if the "Triluminos" name sounds familiar, Sony has used it before. This time, as shown, it's referring to an edge-lighting technology, not the RGB LED backlighting as in 2008.

Sony claims this allows for a wider color gamut compared to LCD TVs using "white" LEDs, as in more potential colors. Since all modern TVs are fully capable of reproducing every color in all current HDTV content, this is a bit of marketing hyperbole.

However, the benefits of this could go beyond cool, futuristic tech and WowNeeto-based marketing. When I've reviewed LED-lit projectors, I've found that the color possible from RGB LEDs looks more realistic than the same Rec. 709-calibrated colors created by color filters (DLP) or dichromatic mirrors (LCD/LCOS) as lit by UHP lamps. One TV engineer I asked about this phenomenon replied "LEDs are like painting with purer paint."

Our own David Katzmaier often remarks in his reviews on the bluish cast seen on some conventional LED-based TVs compared to, say, plasma sets. "It's usually most prevalent in dark areas, but I sometimes see a slight bluish 'coldness' in brighter material and skin tones too. In some cases I see it despite seemingly excellent color measurements from my instruments."

So it's possible that even with the same measured color points, quantum dot-enhanced displays could produce more realistic color. Will they? Will the color mixing required to create Rec. 709 from wildly oversaturated color points cause other issues? What effect will the color filters, which are still necessary on LCDs, have on this "purer" light? These are questions we can't answer until we see the X900 series, and any future TVs with quantum dots.

This whole column and not one "Quantum Leap" joke. Oh dammit.

Atomic Force Microscopy (AFM) image of sparse QDs (white) on a semiconductor background (black). Individual QDs, as well as close-packed small groups can be resolved.

(Credit:
MIT)

The current generation of quantum dot technology requires a primary light source like the blue LEDs in Sony's Triluminos. This won't always necessarily be the case. It will be possible to excite the quantum dots directly. This could be a full QD backlight, but it could be more. How about a direct-emissive display like OLED, but instead of Organic Light-Emitting Diodes, it's sub-pixels filled with red, green, or blue quantum dots. QD Vision calls this a "QLED," and it could have similar performance characteristics as OLED (like a truly infinite contrast ratio). Will it be easier to produce, offer better color, or have even lower power consumption? At this point, we have no idea. Given the production difficulties OLED has had, just the fact that there's something on the horizon that could offer potentially similar performance is exciting.

Bottom line

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Got a question for Geoff? Send him an e-mail! If it's witty, amusing, and/or a good question, you may just see it in a post just like this one. No, he won't tell you which TV to buy. Yes, he'll probably truncate and/or clean up your e-mail. You can also send him a message on Twitter: @TechWriterGeoff.

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Confirmed: Dogs Sneak Food When People Aren't Looking

Many dog owners will swear their pups are up to something when out of view of watchful eyes. Shoes go missing, couches have mysterious teeth marks, and food disappears. They seem to disregard the word "no."

Now, a new study suggests dogs might understand people even better than we thought. (Related: "Animal Minds.")

The research shows that domestic dogs, when told not to snatch a piece of food, are more likely to disobey the command in a dark room than in a lit room.

This suggests that man's best friend is capable of understanding a human's point of view, said study leader Juliane Kaminski, a psychologist at the U.K.'s University of Portmouth.

"The one thing we can say is that dogs really have specialized skills in reading human communication," she said. "This is special in dogs." (Read "How to Build a Dog.")

Sneaky Canines

Kaminski and colleagues recruited 84 dogs, all of which were more than a year old, motivated by food, and comfortable with both strangers and dark rooms.

The team then set up experiments in which a person commanded a dog not to take a piece of food on the floor and repeated the commands in a room with different lighting scenarios ranging from fully lit to fully dark.

They found that the dogs were four times as likely to steal the food—and steal it more quickly—when the room was dark. (Take our dog quiz.)

"We were thinking what affected the dog was whether they saw the human, but seeing the human or not didn't affect the behavior," said Kaminski, whose study was published recently in the journal Animal Cognition.

Instead, she said, the dog's behavior depended on whether the food was in the light or not, suggesting that the dog made its decision based on whether the human could see them approaching the food.

"In a general sense, [Kaminski] and other researchers are interested in whether the dog has a theory of mind," said Alexandra Horowitz, head of the Dog Cognition Lab at Barnard University, who was not involved in the new study.

Something that all normal adult humans have, theory of mind is "an understanding that others have different perspective, knowledge, feelings than we do," said Horowitz, also the author of Inside of a Dog.

Smarter Than We Think

While research has previously been focused on our closer relatives—chimpanzees and bonobos—interest in dog cognition is increasing, thanks in part to owners wanting to know what their dogs are thinking. (Pictures: How smart are these animals?)

"The study of dog cognition suddenly began about 15 years ago," Horowitz said.

Part of the reason for that, said Brian Hare, director of the Duke Canine Cognition Lab and author of The Genius of Dogs, is that "science thought dogs were unremarkable."

But "dogs have a genius—years ago we didn't know what that was," said Hare, who was not involved in the new research. (See pictures of the the evolution of dogs, from wolf to woof.)

Many of the new dog studies are variations on research done with chimpanzees, bonobos, and even young children. Animal-cognition researchers are looking into dogs' ability to imitate, solve problems, or navigate social environments.

So just how much does your dog understand? It's much more than you—and science—probably thought.

Selectively bred as companions for thousands of years, dogs are especially attuned to human emotions—and, study leader Kaminski said, are better at reading human cues than even our closest mammalian relatives.

"There has been a physiological change in dogs because of domestication," Duke's Hare added. "Dogs want to bond with us in ways other species don't." (Related: "Dogs' Brains Reorganized by Breeding.")

While research reveals more and more insight into the minds of our furry best friends, Kaminski said, "We still don't know just how smart they are."

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Bloody Cricket Bat Surfaces in Pistorius Case

Police in South Africa investigating the shooting death of model Reeva Steenkamp, allegedly by boyfriend and Paralympics champion Oscar Pistorius, consider a bloody cricket bat to be a central piece of evidence, according to South Africa's City Press newspaper.

Pistorius, 26, was arrested Thursday and charged with killing Steenkamp, 29, at his home in the South African capitol of Pretoria. His family says the shooting was an accident. He is in jail awaiting a bail hearing Tuesday.

PHOTOS: Paralympic Champion Charged in Killing

The City Press reported Sunday that police are investigating different scenarios involving the bat. Among them is the possibility that the flat-fronted bat was used in a violent argument before the shooting.

The paper also reported that Pistorius might have first shot Steenkamp in the bedroom, and that she possibly fled to the bathroom where she was shot three more times through the door.

When Pistorius' family arrived at the scene before paramedics, they saw him carrying Steenkamp down the stairs and performing mouth-to-mouth resuscitation on her, City Press reported.

Adrian Dennis/AFP/Getty Images; Mike Holmes/The Herald/Gallo Images/Getty Images

Oscar Pistorius: Possibly Incriminating Information Leaked Watch Video

'Blade Runner' Murder Charges: Family Insist Accidental Shooting Watch Video

'Blade Runner' Murder Mystery: Family Speaks Out Watch Video

Pistorius, who is nicknamed the "blade runner" because of the carbon-fiber blades on which he runs, has canceled all his upcoming racing appearances, his agent said Sunday night.

The decision was made to "allow Oscar to concentrate on the upcoming legal proceedings and to help and support all those involved as they try to come to terms with this very difficult and distressing situation," Peet Van Zyl of In Site Athlete Management said in a statement.

Pistorius' father was quoted overnight in the South African paper The Sunday Times saying his countrymen are destroying a national icon.

"There is something fundamentally wrong with our society," Henke Pistorius said. "We build people up into heroes, who overcome immense challenges, only to take great glee in breaking them down."

Family and friends rallied to Pistorius' defense, saying they believe the Paralympic gold medalist shot the South African model by accident after he mistook her for an intruder.

"We have no doubt here that there's no substance for the allegations," uncle Arnold Pistorius said.

Pistorius' best friend, Justin Divaris, told reporters that he received a call from a distraught Pistorius just before 4 a.m. Feb. 14 in which he said there had been a terrible accident, and that he shot Steenkamp.

If convicted, Pistorius could face at least 25 years in jail.
A memorial service for Steenkamp will be held in Port Elizabeth Tuesday evening. Her body has been flown back for the service before being cremated, her family told local media.

Speaking with the media for the first time since her daughter's death in a phone interview with The Sunday Times from her home in Seaview, Port Elizabeth, June Steenkamp said,
"Why? Why my little girl? Why did this happen? Why did he do this? What for?"

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False memories prime immune system for future attacks

IN A police line-up, a falsely remembered face is a big problem. But for the body's police force – the immune system – false memories could be a crucial weapon.

When a new bacterium or virus invades the body, the immune system mounts an attack by sending in white blood cells called T-cells that are tailored to the molecular structure of that invader. Defeating the infection can take several weeks. However, once victorious, some T-cells stick around, turning into memory cells that remember the invader, reducing the time taken to kill it the next time it turns up.

Conventional thinking has it that memory cells for a particular microbe only form in response to an infection. "The dogma is that you need to be exposed," says Mark Davis of Stanford University in California, but now he and his colleagues have shown that this is not always the case.

The team took 26 samples from the Stanford Blood Center. All 26 people had been screened for diseases and had never been infected with HIV, herpes simplex virus or cytomegalovirus. Despite this, Davis's team found that all the samples contained T-cells tailored to these viruses, and an average of 50 per cent of these cells were memory cells.

The idea that T-cells don't need to be exposed to the pathogen "is paradigm shifting," says Philip Ashton-Rickardt of Imperial College London, who was not involved in the study. "Not only do they have capacity to remember, they seem to have seen a virus when they haven't."

So how are these false memories created? To a T-cell, each virus is "just a collection of peptides", says Davis. And so different microbes could have structures that are similar enough to confuse the T-cells.

To test this idea, the researchers vaccinated two people with an H1N1 strain of influenza and found that this also stimulated the T-cells to react to two bacteria with a similar peptide structure. Exposing the samples from the blood bank to peptide sequences from certain gut and soil bacteria and a species of ocean algae resulted in an immune response to HIV (Immunology, doi.org/kgg).

The finding could explain why vaccinating children against measles seems to improve mortality rates from other diseases. It also raises the possibility of creating a database of cross-reactive microbes to find new vaccination strategies. "We need to start exploring case by case," says Davis.

"You could find innocuous pathogens that are good at vaccinating against nasty ones," says Ashton-Rickardt. The idea of cross-reactivity is as old as immunology, he says. But he is excited about the potential for finding unexpected correlations. "Who could have predicted that HIV was related to an ocean algae?" he says. "No one's going to make that up!"

This article appeared in print under the headline "False memories prime our defences"

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Football: City swamp Leeds in FA Cup romp

MANCHESTER, United Kingdom: A Sergio Aguero brace was the highlight of Manchester City's comfortable 4-0 FA Cup fifth round victory over Leeds on Sunday, a win that will lift, at least temporarily, speculation about the future of manager Roberto Mancini.

With City 12 points behind Premier League leaders Manchester United, the FA Cup remains Mancini's most realistic hope of winning silverware this season and Aguero's efforts, together with goals from Yaya Toure and Carlos Tevez, carried his team through to the last eight with the minimum of fuss.

"I think it was really important to win this game. If you score two goals within the first 20 minutes it is easier," said Mancini.

"Our strikers need to continue to score like they did today. If they do that, we can have other chances."

City wasted no time in taking out recent league frustrations on their Championship visitors and, even before their fifth minute opening goal, Leeds 'keeper Jamie Ashdown had been forced to race from his area to beat Aguero to an under-hit back-pass.

Neil Warnock's players were still struggling to come to terms with the task in hand when Yaya Toure left them with a mountain to climb.

The Ivory Coast international exchanged the ball with both David Silva and Tevez in a flurry of passes before advancing into the area and comfortably beating Ashdown and an attempt by Lee Peltier to clear off his line.

It was the start of a half of almost unrelenting City dominance with Tom Lees' timely tackle stopping Aguero, Silva flashing a shot wide and Tevez shooting into the side netting from an Aguero pull-back, all in quick succession.

Finally, after 14 minutes, Leeds succumbed to the inevitable after Lees was harshly judged to have pulled back Aguero on one of his trademark snaking runs into the area.

The Argentinian international took the spot kick himself, calmly converting past Ashdown.

Leeds finally launched a meaningful attack of their own as El Hadji Diouf headed just over from Sam Byram's 15th minute cross.

But, apart from City goalkeeper Costel Pantilimon being forced to punch away a 45th minute free-kick from Ross McCormack, the remainder of the tie quickly degenerated into a question of how many City would score.

It took until the sixth minute of the second half for City to finally find the third goal that rendered any prospect of a Leeds fightback out of the question.

Aguero played a one-two with Silva before continuing a sprint towards the left-hand by-line from where his cross was met on the goal line by Tevez, who forced the ball into the open net.

As City pressed on Yaya Toure might also have extended the lead when he met Silva's cross with a powerful shot which Ashdown parried directly to substitute Jack Rodwell who could only head against the cross-bar with an open goal at his mercy.

As Leeds supporters expressed their growing unrest with manager Warnock, the afternoon might have turned even uglier for the mid-table Championship side had Aguero made decent connection with an eight-yard shot which dribbled through to the goalkeeper.

Aguero finally added the fourth goal that City's superiority merited after 73 minutes, following Silva's well-timed pass picking out the Argentinian's run beyond the Leeds defence.

Aguero did the rest with a confident finish past the advancing Ashdown.

-AFP/ac

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Remember when video discs were the size of LPs?

Pioneer VP-1000 LaserDisc Player

(Credit:
Pioneer)

Years ago, long before the dawn of the DVD or Blu-ray formats, consumer video was strictly all-analog, from the very first broadcasts right up to the introduction of the LaserDisc. The 12-inch, double-sided LaserDisc looked like a giant CD, but the video was analog encoded on two single-sided aluminum discs layered in plastic. The discs that debuted in 1978 had analog audio soundtracks, but later discs featured stereo digital sound. Millions of players were sold in the U.S., but LaserDisc was, even during the height of its popularity, a niche format that appealed mostly to videophiles. It had much greater success in Japan, and was used in 10 percent of all households. LaserDisc video quality was a big step up from VHS and Beta tapes.
Pioneer's LaserDisc players, starting with the VP-1000 in 1980, dominated the market, but in 1981 RCA started a minor format war with its analog CED video discs (an LP-like grooved video disc), but the inferior system faded quickly.

My friends with large LaserDisc collections were skeptical of DVD's quality, and were unhappy with the first DVDs' compression artifacts. The LaserDisc supporters gleefully pointed to poor DVD transfers, ridden with aliasing, blotching, and pixilation woes. LaserDiscs were 100 percent compression-free. There were significant DVD compatibility issues, some discs wouldn't play in some players. I spoke with Geoff Morrison about his take on the LaserDisc, and he said "There was a natural smoothness to the image, because it was analog, and over most televisions [of that era] there wasn't a radical change between a good LaserDisc and the first DVDs." Even the Criterion Collection, known for releasing exquisitely restored editions of classic films, didn't immediately abandon the Laserdisc format.

To be fair, it didn't take all that long for the DVD engineers to sort out the mastering problems, but in the early days it looked like we were going to have an analog vs. digital war on our hands. It didn't happen, but the LaserDisc true believers kept the faith long after DVD reigned supreme. Pioneer continued selling players well into the DVD age and ceased production in 2009.

Did you ever own or watch LaserDiscs? Share your memories in the Comments section.

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Pictures: What the Presidents Brought Home

Photograph by Bill Ray, Time Life Pictures/Getty Images

When paleontologist Paul Olsen (pictured left, in 1970 at 17 years old) first started looking for dinosaurs in 1967, he never dreamed that he'd end up the subject of White House memos between President Richard Nixon and his senior advisers.

Or that one of the dinosaur footprints he discovered would find its way into a presidential collection.

But that's exactly what happened when Olsen and his friend Tony Lessa (right) successfully lobbied for the creation of a park in 1970 near Livingston, New Jersey (map).

The future park, located in a quarry owned by Walter Kidde Precision Instruments, was a budding paleontologist's dream.

The area was covered in dinosaur footprints, such as ones made by Eubrontes gigantis (pictured), and some of them were more than 200 million years old.

"The footprints are very well preserved in that particular spot," said Olsen, now at Columbia University in New York. And the arrangement of some of them—many small footprints associated with one larger set—indicated behaviors that included parental care, he said.

It took Olsen and Lessa two and a half years to get the area designated as a park, but once they did, an Olsen family friend started writing letters to the White House to see if the boys could meet the President.

"[Presidential speechwriter] William Safire said he didn't want President Nixon to be associated with the concept of a dinosaur," said Olsen. The White House staff discussed this while dealing with the Vietnam War, going so far as to write memos on the situation, he said.

Olsen and Lessa never got their meeting with the President. But Nixon ended up sending the teenagers presidential commendations.

Olsen sent the President a cast of the E. gigantis footprint as a thank you. The cast now resides at the Nixon Presidential Library and Museum in Yorba Linda, California.

The actual footprint fossils, stored in a shed at the park, have walked off. "No one knows what happened to them," Olsen said.

February 17, 2013

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WH Chief of Staff on Leaked Immigration Plan: Let's Make Sure It Doesn't Have to Be Proposed

Feb 17, 2013 9:06am

Responding to sharp criticism from Sen. Marco Rubio over the leaked White House immigration proposal, President Obama’s chief of staff Denis McDonough pushed back this morning on “This Week,” in an interview with ABC’s Chief White House Correspondent Jonathan Karl, saying it was up to those in Congress to ensure the president’s proposal would not be sent to Congress.

“He [Marco Rubio] says its ‘dead on arrival’ if it’s proposed. Well let’s make sure that it doesn’t have to be proposed,” McDonough said. “Let’s make sure that that group up there, the gang of eight, makes the good progress on these efforts as much as they say they want to.”

After the White House proposal was leaked, Republican Sen. Marco Rubio of Florida, who is currently part of a bipartisan group at work on legislation to overhaul the immigration system of the United States, issued a statement saying “President Obama’s leaked immigration proposal is disappointing to those of us working on a serious solution. The President’s bill repeats the failures of past legislation.” He went on to say that if it was actually proposed, it would be “dead on arrival” in Congress.

Karl asked McDonough for a response, but said he was not interested in engaging in a political “scrum” with Rubio.

Like “This Week” on Facebook here. You can also follow the show on Twitter here.

SHOWS: This Week

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