Monday, January 25, 2010

ACROSS THE MULTIVERSE: FSU PHYSICIST CONSIDERS THE BIG PICTURE

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Is there anybody out there? In Alejandro Jenkins' case, the question refers not to whether life exists elsewhere in the universe, but whether it exists in other universes outside of our own.

While that might be a mind-blowing concept for the layperson to ponder, it's all in a day's work for Jenkins, a postdoctoral associate in theoretical high-energy physics at The Florida State University. In fact, his deep thoughts on the hypothetical "multiverse" — think of it as a mega-universe full of numerous smaller universes, including our own — are now receiving worldwide attention, thanks to a cover article he co-wrote for the January 2010 issue of Scientific American magazine.

In "Looking for Life in the Multiverse," Jenkins and co-writer Gilad Perez, a theorist at the Weizmann Institute of Science in Israel, discuss a provocative hypothesis known as the anthropic principle, which states that the existence of intelligent life (capable of studying physical processes) imposes constraints on the possible form of the laws of physics.

"Our lives here on Earth — in fact, everything we see and know about the universe around us — depend on a precise set of conditions that makes us possible," Jenkins said. "For example, if the fundamental forces that shape matter in our universe were altered even slightly, it's conceivable that atoms never would have formed, or that the element carbon, which is considered a basic building block of life as we know it, wouldn't exist. So how is it that such a perfect balance exists? Some would attribute it to God, but of course, that is outside the realm of physics."

The theory of "cosmic inflation," which was developed in the 1980s in order to solve certain puzzles about the structure of our universe, predicts that ours is just one of countless universes to emerge from the same primordial vacuum. We have no way of seeing those other universes, although many of the other predictions of cosmic inflation have recently been corroborated by astrophysical measurements.

Given some of science's current ideas about high-energy physics, it is plausible that those other universes might each have different physical interactions. So perhaps it's no mystery that we would happen to occupy the rare universe in which conditions are just right to make life possible. This is analogous to how, out of the many planets in our universe, we occupy the rare one where conditions are right for organic evolution.

"What theorists like Dr. Perez and I do is tweak the calculations of the fundamental forces in order to predict the resulting effects on possible, alternative universes," Jenkins said. "Some of these results are easy to predict; for example, if there was no electromagnetic force, there would be no atoms and no chemical bonds. And without gravity, matter wouldn't coalesce into planets, stars and galaxies.

"What is surprising about our results is that we found conditions that, while very different from those of our own universe, nevertheless might allow — again, at least hypothetically — for the existence of life. (What that life would look like is another story entirely.) This actually brings into question the usefulness of the anthropic principle when applied to particle physics, and might force us to think more carefully about what the multiverse would actually contain."

(Photo: Florida State U.)

Florida State University

'WEEKEND EFFECT' MAKES PEOPLE HAPPIER REGARDLESS OF THEIR JOB

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From construction laborers and secretaries to physicians and lawyers, people experience better moods, greater vitality, and fewer aches and pains from Friday evening to Sunday afternoon, concludes the first study of daily mood variation in employed adults to be published in the January 2010 issue of the Journal of Social and Clinical Psychology. And that 'weekend effect' is largely associated with the freedom to choose one's activities and the opportunity to spend time with loved ones, the research found.

"Workers, even those with interesting, high status jobs, really are happier on the weekend," says author Richard Ryan, a professor of psychology at the University of Rochester. "Our findings highlight just how important free time is to an individual's well-being," Ryan adds. "Far from frivolous, the relatively unfettered time on weekends provides critical opportunities for bonding with others, exploring interests and relaxing — basic psychological needs that people should be careful not to crowd out with overwork," Ryan cautions.

The study tracked the moods of 74 adults, aged 18 to 62, who worked at least 30 hours per week. For three weeks, participants were paged randomly at three times during the day, once in the morning, the afternoon and the evening. At each page, participants completed a brief questionnaire describing the activity in which they were engaged and, using a seven-point scale, they rated their positive feelings like happiness, joy, and pleasure as well as negative feelings of anxiety, anger, and depression. Physical symptoms of stress, such as headaches, digestive problems, respiratory ills, or low energy, also were noted.

The results demonstrated that men and women alike consistently feel better mentally and physically on the weekend. They feel better regardless of how much money they make, how many hours they work, how educated they happen to be, or whether they work in the trades, the service industry, or in a professional capacity. They feel better whether they are single, married, living together, divorced, or widowed. And, they feel better regardless of age.

To tease out exactly why weekend hours are so magical, the researchers asked participants to indicate whether they felt controlled versus autonomous in the task they were engaged in at the time of the pager signal. Participants also indicated how close they felt to others present and how competent they perceived themselves to be at their activity.

The findings indicated that relative to workdays, weekends were associated with higher levels of freedom and closeness: people reported more often that they were involved in activities of their own choosing and spending time with more intimate friends and family members. Surprisingly, the analysis also found that people feel more competent during the weekend than they do at their day-to-day jobs.

The results support self-determination theory, which holds that well-being depends in large part on meeting one's basic psychological needs for autonomy, competence, and relatedness. This study, conclude the authors, "offers one of the first substantive and theory-based explanations for why wellbeing tends to be more favorable on the weekends: People experience greater autonomy and relatedness, which are, in turn, related to higher wellness." By contrast, write the authors, the work week "is replete with activities involving external controls, time pressures, and demands on behavior related to work, child care and other constraints." Workers also may spend time among colleagues with whom they share limited emotional connections.

The study also raises questions about how work environments can be structured to be more supportive of wellness. "To the extent that daily life, including work, affords a sense of autonomy, relatedness, and competence, well-being may be higher and more stable, rather than regularly rising and falling," the researchers conclude.

(Photo: U. Rochester)

University of Rochester

ANCIENT EGYPTIAN COSMETICS: 'MAGICAL' MAKEUP MAY HAVE BEEN MEDICINE FOR EYE DISEASE

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There's more to the eye makeup that gave Queen Nefertiti and other ancient Egyptian royals those stupendous gazes and legendary beauty than meets the eye. Scientists in France are reporting that the alluring eye makeup also may have been used to help prevent or treat eye disease by doubling as an infection-fighter.

Christian Amatore, Philippe Walter, and colleagues note that thousands of years ago the ancient Egyptians used lead-based substances as cosmetics, including an ingredient in black eye makeup. Some Egyptians believed that this makeup also had a "magical" role in which the ancient gods Horus and Ra would protect wearers against several illnesses. Until now, however, modern scientists largely dismissed that possibility, knowing that lead-based substances can be quite toxic.

In earlier research, the scientists analyzed 52 samples from ancient Egyptian makeup containers preserved in the Louvre museum in Paris. They identified four different lead-based substances in the makeup. In the new study, they found that the substances boosted production of nitric oxide by up to 240 per cent in cultured human skin cells. Modern scientists recognize nitric oxide as a key signalling agent in the body. Its roles include revving-up the immune system to help fight disease. Eye infections caused by bacteria can be a serious problem in tropical marshy areas such as the Nile area during floods, the scientists note. Therefore, the ancient Egyptians may have deliberately used these lead-based cosmetics to help prevent or treat eye disease, the researchers suggest, noting that two of the compounds do not occur naturally and must have been synthesized by ancient Egyptian "chemists."

(Photo: Wikimedia Commons)

American Chemical Society

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