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Sunday's Doonesbury- Epidemics

Big Bang May Have Created a Mirror Universe Where Time Runs Backwards

Why does time seem to move forward? It’s a riddle that’s puzzled physicists for well over a century, and they’ve come up with numerous theories to explain time’s arrow. The latest, though, suggests that while time moves forward in our universe, it may run backwards in another, mirror universe that was created on the “other side” of the Big Bang.

Two leading theories propose to explain the direction of time by way of the relatively uniform conditions of the Big Bang. At the very start, what is now the universe was homogeneously hot, so much so that matter didn’t really exist. It was all just a superheated soup. But as the universe expanded and cooled, stars, galaxies, planets, and other celestial bodies formed, birthing the universe’s irregular structure and raising its entropy.

ne theory, proposed in 2004 by Sean Carroll, now a professor at Cal Tech, and Jennifer Chen, then his graduate student, says that time moves forward because of the contrast in entropy between then and now, with an emphasis on the fact that the future universe will so much more disordered than the past. That movement toward high entropy gives time its direction.

The new theory says a low entropy early universe is inevitable because of gravity, and ultimately that’s what gives time its arrow. To test the idea, the theory’s proponents assembled a simple model with nothing more than 1,000 particles and the physics of Newtonian gravity. Here’s Lee Billings, reporting for Scientific American:

The system’s complexity is at its lowest when all the particles come together in a densely packed cloud, a state of minimum size and maximum uniformity roughly analogous to the big bang. The team’s analysis showed that essentially every configuration of particles, regardless of their number and scale, would evolve into this low-complexity state. Thus, the sheer force of gravity sets the stage for the system’s expansion and the origin of time’s arrow, all without any delicate fine-tuning to first establish a low-entropy initial condition.



A Step Toward Artificial Cells, Built from Silicon

In a step toward sophisticated artificial cells, scientists have engineered a silicon chip that can produce proteins from DNA, the most basic function of life.

The system, though relatively simple, suggests a path to mimicking life with partly manufactured components, says Roy Bar-Ziv, a materials scientist at the Weizmann Institute of Science in Israel, who is leading the work.

Cells constantly create proteins from instructions coded in DNA sequences. How much of each protein is made is controlled by other genes, often in complicated feedback loops. Bar-Ziv calls his cell-on-a-chip “a new system allowing us to examine how genes are turned on and off outside the living cell.”

The chips were created using a technique Bar-Ziv’s lab developed several years ago to anchor DNA to silicon by first coating the surface with a light-activated chemical. They used patterns of light to create spots where DNA binds and assembles into toothbrush-like bundles. Each DNA brush was confined to a small, round compartment. These compartments were joined by a narrow capillary 20 micrometers wide to a larger channel, which carried a flow of liquid extracts from bacterial cells—all the ingredients needed to synthesize proteins from the DNA brushes.



Physicists solve decade-old quantum mechanics problem

by: Kristian Sjøgren

Danish scientists have solved the quantum mechanics problem that has been teasing them since the 1930s: how to calculate real life behaviour of atoms.

The formula helps them work out how to optimise the transport of information from one atom to another. This will be necessary if we are to one day construct quantum computers.

"The problem has been to calculate when atoms do one thing or another in the real world. We have been able to calculate this in theory, but when we experiment and insert data into existing models, they fall apart,” says co-author Nicolaj Thomas Zinner, associate professor at the Department of Physics and Astronomy at Aarhus University. “We have finally solved that problem."

The study was recently published in Nature Communications.



Inside The Collapse Of The New Republic


Last Friday morning, Chris Hughes, the owner of The New Republic, and Guy Vidra, the magazine’s C.E.O., presided over a meeting at the publication’s Penn Quarter offices in Washington, D.C. It had been a busy twenty-four hours: a day earlier, Hughes had forced out the magazine’s editor, Franklin Foer, and Vidra had announced that the hundred-year-old opinion magazine, which was founded to “bring sufficient enlightenment to the problems of the nation,” would be reduced from twenty to ten issues a year and would move to New York, where it would be reinvented as a “vertically integrated digital-media company.” Minutes before the Friday meeting began, most of the magazine’s writers and editors had resigned in protest.

Hughes, a co-founder of Facebook with an estimated fortune of more than half a billion dollars, bought T.N.R. in 2012, and the Washington headquarters was a reflection of his ambitions. The office is bright, with an open floor plan for writers and a row of well-appointed editors’ offices with windows overlooking the National Portrait Gallery. Bound volumes from the magazine’s history line a long wall, and a small library decorated with photographs of T.N.R.’s founders and early contributors serves as a retreat for quiet reading. Hughes signed a ten-year lease and told his writers that the magazine would stay in Washington for a long time.

As the remaining staff gathered around a long conference table, Vidra set up a computer with his notes on it. Hughes joined from New York via a video-conferencing system.

Vidra read from his laptop. Hughes had hired him in October from Yahoo, and he spoke in a Silicon Valley-inflected jargon that many of T.N.R.’s journalists found grating and bewildering. As soon as he arrived, he embarked on a project to transform the modest-circulation journal of politics and culture into something more like a technology company. In conversations with Foer, he deemed it necessary to rid the staff of old-timers who he believed were ill-suited for the transformation.



Massive volcanic eruptions set the stage for dinosaurs’ demise

It's now widely accepted that the impact of an asteroid at Chicxulub in Mexico's Yucatan region finished off any dinosaurs that we don't currently refer to as birds, while triggering a mass extinction that wiped out a lot of other species. But that hasn't ended the debate regarding the dynamics of the extinction event, with other ecological influences getting consideration as contributing to the dinosaurs' vulnerability.

One potential contributor that's hard to overlook is situated in western India: the Deccan Traps. These enormous deposits are built of layer upon layer of volcanic rock, suggesting a series of flood eruptions took place over thousands of years. These eruptions happened suspiciously close to the start of the mass extinction—close enough that some researchers argued that it was the eruptions that killed off the dinosaurs. There was, after all, precedent; the eruptions that formed the Siberian Traps have been blamed for a mass extinction that was so severe, it's known as the The Great Dying.

To help settle the issue, an international team of researchers has gone back and obtained the most precise dates for the eruptions yet. The dates show that the eruptions started nearly a quarter-million years before the onset of the mass extinction but continued for roughly 750,000 years, meaning they spanned the extinction event. This supports the idea that the eruptions helped set the stage for the end of the dinosaurs.



Weekend Toon Roundup 2- The rest




The Issue


Weekend Toon roundup 1- Torture, American Style

A Strange New Gene Pool of Animals Is Brewing in the Arctic

The journey began in spring 2010, just as the sea ice surrounding the North Pole began its annual melt. Two bowhead whales, 50-foot-long behemoths that scour the Arctic seas for plankton, each started from their homes on opposite sides of North America—one in the Beaufort Sea north of Alaska, the other in Baffin Bay on the west side of Greenland. As the summer progressed, sea ice shrank (to its third-lowest cover in the last 30 years), and the whales swam toward each other through the now ice-free passage above the continent. Two independent teams of scientists from Canada and the United States watched the whales closely via satellite. “We were all pretty excited,” recalls Kristen Laidre, a biologist at the University of Washington and member of the U.S. team.

In September, in an inlet some 1,800 miles north of Fargo, North Dakota, where the North American landmass dissolves into the Arctic Ocean, the whales met in the middle. They spent two weeks together, and although not much happened before they turned around, the meeting was historic. The fossil record indicates the last time Pacific and Atlantic bowhead whales came into contact was at least 10,000 years ago.

In the last 40 years, the Arctic has warmed by about 3.5 degrees Fahrenheit, more than twice the overall global rise in that same period. Already grizzly bears are tromping into polar bear territory while fish like cod and salmon are leaving their historic haunts to follow warming waters north. One tangible result of the migration, scientists report, is that animals will learn to live with new neighbors. But polar biologists worry that animals could get a little too friendly with each other. With less ice clogging Arctic seas, whales are ranging farther; meanwhile, animals like seals that breed on the ice have fewer places to go. In both cases, the chances of encountering a different species jump. “All of a sudden, hybridization will skyrocket,” says Brendan Kelly, a polar ecologist at the National Science Foundation.

The first confirmed cross between a polar bear and a grizzly bear—a white bear with brown patches—was documented in 2006; genetic analysis of a second, found in 2010, revealed that its mother was also a hybrid, suggesting that more instances are happening under scientists’ radar. In 2009, a biologist at the National Marine Mammal Laboratory photographed a probable bowhead/right whale hybrid in the Bering Sea. More hybrids are possible. Kelly and his coauthors have counted 34 opportunities for hybridization across 22 Arctic or near-Arctic species, based on the animals’ genetic compatibility and geographic range. The list includes potential hybrids of ringed and ribbon seals, Atlantic walrus and Pacific walrus, and beluga whales and narwhals.



Gov. Declares Chick-fil-A Defeat 'A Win for Vermont'

When in 2011 Chick-fil-A sued Bo Muller-Moore, a folk artist from Vermont, for using a slogan similar to their famous "eat mor chikin," no one thought he would beat the national chain. Though Muller-Moore had been using his "Eat More Kale" phrase on t-shirts and bumper stickers since 2000, when he tried to trademark the phrase — certainly as the popularity of kale began to rise — Chick-fil-A stepped up with a cease-and-desist letter. Today, the AP reports that Muller-Moore successfully won his right to use the vegan-friendly phrase.

Though his original trademark application was blocked, a judge has overturned that decision. Vermont Gov. Peter Shumlin released a statement: "The message is out: Don't mess with Vermont. And don't mess with Bo. This isn't just a win for the little guy who stands up to a corporate bully; it's a win for our state. In Vermont, we care about what's in our food, who grows it, and where it comes from."

Atlanta-based Chik-fil-A played nice after the decision was announced, saying, "Cows love kale, too."

Muller-Moore plans to continue to emblazon t-shirts with the phrase, "Eat More Kale" as well as the more tongue-in-cheek, "Kale Isn't Chicken."

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