February 20, 2010
Posted: 08:35 PM ET
Most scientists agree that global warming is real, but disagreement abounds about what to do about it.
The idea of taking carbon out of the atmosphere and storing it so that it can't warm the planet has been pretty widely discussed. Here are some techniques you might not know about; they involve large-scale geoengineering.
Basically, scientists are trying to figure out how to cool the planet by reflecting some of the sunlight back.
One idea is shooting sulfur particles into the stratosphere, which could decrease the temperature of the planet by about 2 degrees Celsius, said experts today at the American Association of the Advancement of Science meeting. Ken Caldeira of the Carnegie Institution says cooling methods like this are a little like chemotherapy for cancer patients - they solve problems, but have their own side effects.
A critic of this proposal, Martin Bunzl of Rutgers University, cautions that this approach could disrupt the monsoon cycle and potentially lead to famines. The dynamics of this on precipitation are also poorly understood, he said. In other words, it's like a doctor telling a patient "here’s something we can try" without knowing how it works.
"There’s a substantial risk of ecological effect," he said. "We don’t really know how long particles we put into the stratosphere remain in the stratosphere."
Another alternative is lightening clouds with sea salt. Philip Rasch of Pacific Northwest National Laboratory says the trade-off here is that you're getting brightening in local regions, whereas the sulfur method brightens the entire globe a little bit.
Right now a lot of what we know about these methods comes from computer modeling. Will they be feasible for the planet? More is yet to be learned.
February 19, 2010
Posted: 04:02 PM ET
You've probably had moments watching science fiction films when you thought, "Naw, that couldn't happen." And it's true - sci-fi movies often contain elements that don't conform to the laws of physics.
But modern science can say a lot about the plausibility of such things as stopping an asteroid from destroying the planet, and these are teachable moments, experts said today at the annual meeting of the American Association of the Advancement of Science in San Diego, California.
Take the asteroid example: films such as "When Worlds Collide" are good about estimating the impact of celestial objects hitting our planet, said Sidney Perkowitz, Emory University physicist and author of "Hollywood Science." In real life, the Tunguska Event, in which a meteor hit part of Siberia, Russia, in 1908, decimated hundreds of square miles of forest.
The Barringer Crater in Arizona, nearly a mile wide, was also created by a meteor. Science fiction movies, however, often incorrectly portray the "save the day moment," since not even an H-bomb has the power to deflect an asteroid, he said.
The powers of superheroes and villains do bring up important concepts in physics, said James Kakalios, technical consultant on the recent "Watchmen" movie and a physicist at the University of Minnesota. For instance, quantum tunneling - the idea that particles can pass through energy barriers - is how Dr. Manhattan teleports in "Watchmen" and how Kitty Pryde walks through walls in "X-Men." Dr. Manhattan's blue color can be explained through a phenomenon called Cerenkov radiation, he said, with the blue glow resulting from the leakage of high-energy electrons.
Believability is important to filmmakers because they don't want viewers' attention to drift away from the story, Kakalios said. He noticed, for instance, that in "Iron Man," Tony Stark is using the correct soldering tool and in the right way. "So you're not thinking about Robert Downey Jr. playing a role, you're thinking about Tony Stark making an Iron Man suit," he said.
You can watch Kakalios' popular YouTube video about the science of "Watchmen" to learn more. And watch for more on the science of superheroes on Monday on CNN.com.
November 23, 2009
Posted: 04:55 PM ET
Alarmists take note: The planet is intact after particles began smashing into each other at the Large Hadron Collider today.
For the first time, the $10 billion machine circulated two proton beams simultaneously in its 17-mile tunnel underneath the border between France and Switzerland.
This is a major step toward finding the answers to fundamental physics questions about the nature of matter in the universe, and how the world as we know it began.
“The events so far mark the start of the second half of this incredible voyage of discovery of the secrets of nature,” said Tejinder Virdee, spokesperson for the Compact Muon Solenoid experiment, in a statement.
The particle collisions are finally happening despite discredited theories that the accelerator could produce a black hole that could swallow the universe, and that it is being sabotaged from the future. Read more about these theories
The project appears to have rebounded from a substantial setback in September 2008. Just nine days after it started up, one of the 25,000 joints that connect magnets in the LHC came loose, and the resulting current melted or burned some important components of the machine, said Steve Myers, director of accelerators at the European Organization for Nuclear Research (CERN).
The collider has drawn thousands of physicists from around the world together in a collaborative search for never-before-seen particles and new properties of nature. These particles include the Higgs boson, which theoretically gives mass to matter.
Today's collisions are relatively low-energy; the next step is to get particles colliding at higher energies than ever before. The accelerator should reach an energy of 1.2 TeV (teraelectronvolts, or a million million electronvolts) per beam by Christmas if all goes well, CERN said.
November 18, 2009
Posted: 12:14 PM ET
Happy 150th anniversary to the Riemann Hypothesis, one of the most important math problems ever!
Proposed by Bernhard Riemann in 1859, the Riemann Hypothesis deals with prime numbers. You may recall that a prime number is a positive whole number that has only two positive whole number divisors: one and itself. The first of them are 2, 3, 5, 7, 11, 13, in order.
This hypothesis would be able to provide a better estimate than ever before of a special function denoted as Pi(x). Pi(x) represents the number of prime numbers that are no bigger than x, where x is a positive number. For example, Pi(14) would be 6, because there are six prime numbers (2, 3, 5, 7, 11, 13) no bigger than 14. That's probably the most understandable explanation you're going to get that doesn't involve "zeta functions" and other technical terms.
Given that many of the best mathematicians have tried and failed to provide a solution, the proof is probably not easy or obvious, says Peter Sarnak, professor of mathematics at Princeton University and an authority on the subject. “Most experts expect that a proof will require a major new insight into the structure of whole numbers and the prime numbers,” he said.
But if you can solve it, the Clay Mathematics Institute will give you $1 million.
A proof would have implications not only for mathematics, but also for cryptography and computer science, says Ramin Takloo-Bighash, associate professor at the University of Illinois at Chicago. Internet security protocols, after all, are largely based on prime numbers. Experimental and theoretical evidence has supported the truth of the Riemann Hypothesis, although there are a small number of naysayers who say it can’t be proven, Takloo-Bighash said.
Still, there’s enough confidence in the truth of the Riemann Hypothesis that mathematicians have established “conditional” theorems, which can never be validated until someone proves the 150-year-old problem, says Kenneth Ribet, professor of mathematics at the University of California, Berkeley.
Riemann's paper on the subject was first published in November 1859, but no one knows the day. So, the American Institute of Mathematics picked a Wednesday in the middle of November to celebrate the 150th anniversary, said Brian Conrey, executive director.
Intrigued? Stop by one of these lectures today.
July 20, 2009
Posted: 10:03 AM ET
Keeping in touch with older relatives can be challenging when they don't use e-mail. You can't send grandparents digital photos unless they're techno-savvy, so you'll have to find a decent printer or pay to print them out. Then, you have to put it all in an envelope, and stick on proper postage. But maybe you're traveling and don't have time for all that, or don't want to feel stuck in the 1990s.
A new Web site called Sunnygram is helping update and enhance communications between young people and their relatives who do not use the Internet.
Co-founder Matt Ahart was inspired to start the service when he found himself sending e-mails to his mother so that she could print them out and show them to his grandmother. What if there were a service that could facilitate electronic correspondence between people and their grandparents?
The idea is simple: Your older relative gets an e-mail address that you can write to, and Sunnygram prints out your messages and photos and sends it via snail mail in a weekly "newsletter" that's a lot prettier than an e-mail printout. Then, the relative has the option of responding in writing on personalized stationary, or electronically by calling a phone number and leaving a voice message, which gets transcribed and sent to you in an e-mail. The service provides unlimited e-mail and photo printing, and any number of family members and friends can correspond with the designated holder of the e-mail address.
Sunnygram also reminds you when a special occasion is coming up, such as Mother's Day or Father's Day, in addition to reminding you to write to your relative if you haven't in a while. "Our users can rest assured that Grandma won’t be forgotten," Ahart said.
Since launching in April, Sunnygram has been adding customers around the U.S. and the world, including members of the military writing to their elderly relatives. And some people are using it to bridge communication gaps that don't necessarily have to do with age. Sunnygram has been used among family members of people in prison. "It’s not just about age or technological savvy - sometimes other circumstances in their lives cause them to not be able to check email, but to have access to mail, so we step up in that situation," Ahart said.
The service costs $9.95 a month, with a one-month free trial. The service will also soon launch a Facebook application, Ahart said.
June 17, 2009
Posted: 03:51 PM ET
At 12:00 a.m. Saturday, Facebook handily provided a second-by-second countdown for members waiting in anticipation to create a username. I know because I was signed in, of course. The social-networking giant had clearly anticipated that people like me would be standing by, worrying that someone else would beat us to our first choices. After all, more than 50,000 users indicated they "like" the announcement about the username feature.
As soon as the prompt popped up, I immediately typed in my choice (Hint: It's a variation on my name, containing the word "monster") and clicked the word "Available," hesitating briefly when Facebook informed me that this choice of username was irreversible. Was it available? YES! I went to sleep satisfied with my new identity, and with the knowledge that I had a unique URL pointing to my profile - almost like a personal Web site someone else had just designed for me.
Some people don't think usernames are so important, but as a relatively early participant in the online world I've put a lot of stock in them - so much that I have emotional attachments to certain names. In fact, since I first got an America Online account in 1996 (dial-up modem, pay per hour), I have created at least 16 different usernames for various online accounts.
At the end of the last century, I felt pretty secure with the usernames that I had created, as if they somehow belonged to me in a way that transcended the AOL welcome screen. These were my Internet identities and, in many cases, the only way that people out in the virtual world knew me. They were variations on my name or my interests, and no one else could send messages from them on AOL. My usernames defined me in several teenage and Jewish-themed chat rooms (not to mention the Star Trek role-playing chat room I got roped into joining a couple of times).
But today, AOL is no longer the dominant player in e-mail, and the same usernames I'd chosen for AOL weren't available anymore when I transitioned to other services such as Gmail. In fact, by the time I figured out that my cutesy screen names on AOL seemed less useful than firstname.lastname on Gmail, email@example.com and firstname.lastname@example.org had been claimed by others. Unless you sign up with a popular e-mail or social media service early, you may find yourself at a loss of how to represent yourself, because the identity you've always known and loved belongs to someone else.
There is something disconcerting about knowing that, while early in online circles I've stood behind the name "Bizzie," I am NOT "Bizzie" on Facebook, MySpace, Twitter, Flickr, or even bizzie.com. In fact, I have no idea who those people are. Should I? Do we all have something in common? Is this yet another means of forging connections between total strangers around the world?
In any case, while the username feature on Facebook does open the doors to all kinds of bizarre monikers, drifting away from its traditional "real name" approach, the essential Facebook interface with all of your "real life" information is essentially the same. Plus, I like the bonus of having a personalized URL with a "monstrous" nickname that seems to keep reemerging partly because of social media.
What do you think about the Facebook username feature? Are you using your real name, or something totally different?
March 13, 2009
Posted: 12:09 PM ET
Pi is the ratio of circumference to diameter of a circle. Celebrate it on Saturday, March 14!
In honor of Pi Day, March 14 (because it's 3/14, like 3.14), I came up with the basis for this song, inspired by Don McClean’s 1971 song “American Pie,” when I was in high school. Feel free sing along with that tune.
A long, long time ago, it was one December when I thought I'd found the end of pi.
Did you write the law of sines, or draw two perfect parallel lines
Books, eraser, graphing paper, I was just a young number chaser
“We know it’s not the pi you eat, this pie’s a far more delicate treat
I met a guy in Period 3 who seemed like he could help me
So why, why can't I calculate pi
–p.s. Tell us how you're celebrating Pi Day this year. It's also the birthday of Albert Einstein! And, check out the Science Channel's salute to pi for more information about one of the most important mathematical constants.
March 3, 2009
Posted: 12:56 PM ET
Square Root Day celebrates perfect squares like these. How many more can you name?
For years I have been celebrating March 14 (3/14) as Pi Day, which I have always considered the mathematical holiday of the highest importance - I mean, come on, it's Albert Einstein's birthday! - and never thought about commemorating any other day for its numerical beauty.
But today, I have been out-geeked. Today, it turns out, is Square Root Day. That's because it's 3/3/09, and 3 x 3 = 9, meaning 3-squared equals 9. I had never considered that this relationship between month, day, and year occurs so rarely. In fact, this "square root" coincidence in dates only happens nine times every century - the last one being 2/2/04.
How should you celebrate Square Root Day? According to CNET, a teacher in Redwood City, California, has organized a contest. Apparently, people will cut root vegetables into squares or make foods into the square root symbol shape.
In addition, perhaps you can listen to the song by Huey Lewis and the News, "Hip to be Square."
For more on Square Root Day and other math holidays, check out the Cybrary Man Web site.
And, stay tuned for my Pi Day tips next weekend.
February 25, 2009
Posted: 10:53 AM ET
Common ravens, contrary to what was thought, sometimes forage in gangs.
You may think of ravens as solitary creatures rapping at chamber doors, but new research shows that some of young ones form gangs when they look for meals, which consist of animal carcasses.
Gangs, in this context, mean groups of juvenile ravens that forage together and overwhelm the territorial adults defending the animal carcass, said researcher Sasha Dall of the University of Exeter in the United Kingdom, in an e-mail. In other words, the kids get together try to chase off the adults defending the food, which may influence their social standing among their peers.
This is the first time that flock foraging has been observed in common ravens, Dall said. In a typical raven roost, a bird attains dominance by finding a carcass alone.
"Since most birds will therefore have to suffer being bullied a lot, there is a strong advantage to doing things to avoid giving any one bird such finder advantages," Dall said. "Turns out foraging in gangs is one such tactic."
In fact, the birds' behavior can be explained by game theory, a branch of mathematics that looks at strategic interactions, Dall's research found. The ravens forage in gangs when searching for food alone is no more efficient than foraging with others, the model shows. It's unlikely that the birds are consciously making such calculations, however, and these responses are likely hard-wired, Dall said.
Any analogies to human behavior are limited, but the research does illustrate how food availability, environment, and other external factors can influence social advancement and the stability of groups, Dall said. Scientists believe human ancestors also faced problems of food scarcity, and one solution to surviving in particular environments is to pool the food-finding efforts. If the group solution works in particular circumstances, it's "nevermore" to individual foraging.
The research is published Wednesday in the journal PLoS One.
February 20, 2009
Posted: 12:32 PM ET
Former Vice President Al Gore addresses the American Association for the Advancement of Science.
From former Vice President Al Gore's speech to a slew of fascinating presentations, the annual meeting of the American Association for the Advancement of Science in Chicago, Illinois, was a whirlwind tour of innovative ideas. Here are some highlights of what we did:
-Saw Gore's presentation: Given that pop-culture conferences have concerts as their evening highlights, it makes sense that the AAAS would have America's climate-change rock star - who recently won a Grammy, no less - to get people on their feet. More than a thousand scientists, journalist, educators and students greeted Gore with a standing ovation as he took the stage.
In his speech, Gore identified a common thread between global warming, our national security and the world financial meltdown - our "absurd" dependence on carbon-based fuels. When you pull on the thread, he said, "then all three of these crises can begin to unravel.” The solution: shifting to an infrastructure based on fuels that are free, such as solar and wind power, and bolstering the science of clean and sustainable energy.
Gore seemed optimistic about Obama’s appointments to the Cabinet and the direction our country is taking to address the issue of climate change, which he called "a historic struggle." He emphasized the importance of us all working together as a species in order to prevent further threats to the entirety of human civilization.
Through a series of slides, which included the most recent scientific findings on climate change, Gore communicated his "inconvenient truth" to the audience while urging scientists to get more involved in their communities. He also called on scientists to get involved in politics, to speak out as “civic scientists” and to “find ways to communicate the truth." He concluded by saying, “Keep your day job, but start getting involved in this historic debate. We need you."
P.S. Gore uses an iPhone, too - he had to turn it off during the speech.
-Learned about stem cells: Bone marrow is one important source of adult stem cells, researchers say. And did you know that humans make 10 billion red blood cells every hour of every day? Dr. Will Li of the Angiogenesis Foundation talked about the potential of endothelial progenitor cells in the marrow for treatments of conditions such as diabetes.
-Got in touch with our emotions: People commonly feel better by writing their feelings down, and now scientists are beginning to understand why. Brain-imaging studies indicate that putting your feelings into words has the effect of regulating emotions, said Matthew Lieberman of the University of California, Los Angeles.
-Became kissing experts: Researchers presented their findings on the hormones involved in kissing, and the role of kissing in beginning (or ending) relationships. Full story
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