Wednesday March 17, 2010
One of the great endeavors of theoretical physics is the drive to create a single "theory of everything," which would provide a single theory that explains all of the interactions in the universe under one over-arching framework. Right now, physics explains gravity under general relativity, while everything else in the universe falls under the Standard Model of quantum physics. Combining these together into one single (and hopefully concise) theory has been a goal for decades, but no one's succeeded. String theory is definitely the most popular approach, but there are a variety of other theories being proposed (such as loop quantum gravity), all of which require a lot of work before they could be taken as serious contenders by most physicists.
So what sorts of problem would this "theory of everything" have to solve? Well, these are the problems outlined by Lee Smolin as the Five Great Problems in Theoretical Physics. Not all physicists agree that these are really problems (for example, the "foundations" problem is dismissed as irrelevant by many physicists and many think the "tuning" problem is resolved by an appeal to a multiverse), but any "theory of everything" would really need to provide answers to several of these problems.
For now, it's hard enough to disprove any of the theories, and finding evidence that confirms one over the other is nearly as difficult. The strongest evidence is in support of string theory, which has been shown (in some cases) to match the black hole entropy predictions of Stephen Hawking. Until some of the other theories get a prediction that matches established physics as solidly as this, string theory is probably going to remain in the forefront.
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Tuesday March 16, 2010
This weekend, I had a load of fun watching a new interactive science show that came to a nearby college. More importantly, so did my son. The show, Doktor Kaboom!, is the brainchild of actor and science enthusiast David Epley, who built the entire show around the idiosyncratic, German-accented scientist character that he developed.
David Epley as Doktor Kaboom!
Source: DoktorKaboom.com (used by permission)
And I'm not the only one who's caught on to Doktor Kaboom. In an interview with me before the show, Epley talked about his amazing success with the character he developed just two-and-a-half years ago.
I'm going all over the place. I'm booked solid for this year, already booked solid for next year. We've got a 9-day run at the Kennedy Center for next April. So it's going gangbusters. It's what I'm supposed to be doing, is what I tell people. If that makes sense...
Watching Epley on stage as Doktor Kaboom, it's hard to believe that just three years ago the character didn't exist ... but it's easily believe that he's meant to play the role. From quirky science facts, to goofy demonstrations, to heartfelt appeals to apply science in daily life, Doktor Kaboom! is engaging for kids and adults alike.
And that's Epley's goal with this show, and is one which - again and again - I return to on this blog. Everyone in society should be engaged, at some level, in the activities of science. Maybe not as an active part of their career, but they should at least be aware of how scientific thinking affects their life, instead of feeling disconnected from it. Again, Epley is on the same page:
There's a point where we all love science, as kids. The wow factor of it. Then there's something that happens around middle school where people start to turn away from it and think, "It's not for me. It's too hard. It's for the smart kids." And I want to remind adults that it is for them, it is for everyone. I want to remind them of the time they loved science. And, of course, introducing the kids to that.
Some people think that there's a certain "type of person" who is supposed to be doing science (I know this because some of these people e-mail me letters when I suggest that science education should be encouraged for everyone), and I just don't buy into this narrative. When we're young, we're all scientists. Epley reminds his audiences of this regularly, and it's a great service he's doing.
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Wednesday March 10, 2010
Just as I was about to slink off to return to bed in the wee early hours of the morning, I decided to clean out my e-mail inbox so that the junk would be gone and I'd be ready to get some work done when I actually wake up tomorrow morning. One of the e-mails had an announcement which I realized needed posted immediately.
It turns out that Sean Carroll - CalTech theoretical cosmologist, blogger at Discover Magazine's Cosmic Variance blog, and author of From Eternity to Here: The Quest for the Ultimate Theory of Time - will be on one of my favorite television shows, Stephen Colbert's The Colbert Report on Comedy Central, this evening - Wednesday, March 10, at 11:30 pm - promoting his book (which, I swear, Sean, I will finish reading and review. I have been a bit busy lately giving all my money away).
For those who miss the show because of early bedtimes or lack of Comedy Central (I suffer from both myself), The Colbert Report offers their entire show online through their website ColbertNation.com (though, sadly, no longer through Hulu.com), so you can check out the March 10 episode there to see what Sean has to say about the nature of time itself! Check back here tomorrow morning for an update on what was covered and a link to the interview!
Update 3/11/10: The video of the interview is available through Colbert Nation at this link. It's a very interesting discussion, focusing on the ephemeral nature of time. Carroll discusses how time is really sort of like taking cake batter and baking it into a cake, by adding complexity and structure to the more uniform starting position. His explanation for this specific set of low-entropy initial condition of the universe is the common response from cosmologists - we live within a multiverse, and happen to be in a sub-section of the multiverse where there initial conditions had an incredibly low entropy. Time is therefore a by-product of the universe "winding down" from low entropy to high entropy. But he explains it much better, so check out the video.
Monday March 8, 2010
In a recent speech about new investments in energy efficient homes (check out the speech itself on Hulu), President Obama mentioned a desire to seek out all options to solve our energy problems. He gets a triple bang out of these sorts of energy efficiency initiatives, of course, because (1) the work is performed by laborers in the United States (2) using mostly materials manufactured in the United States (because, as he points out, it's hard to bring an energy-efficient window over from China), and (3) saves money on the subsequent energy bills. Plus there are secondary benefits, such as less power demand, less need for coal, less environmental pollution, and so on.
(Whether all of these benefits warrant the investment of these rebates is something I'll leave to the more argumentative policy wonks. I bought some energy efficient windows last fall and, to be honest, now that spring is coming I'm feeling more concern about paying off the financing than the euphoria I felt when I eliminated a mid-November draft from my bedroom. But I still think that, overall, it was probably worth the expense.)
Barack Obama, April 2009
Source: Dennis Brack-Pool/Getty Images
During the speech, however, President Obama also mentioned the recent announcement of a new nuclear power plant in Burke, Georgia - the first nuclear power plant to be built on U.S. soil in three decades. (Again, this helps not only with power production, but gives jobs to skilled constructors, manufacturers, and other workers.)
The problem with nuclear power is that it's based on nuclear fission (although Europe continues to experiment with the more efficient nuclear fusion), which leaves behind a substantial amount of nuclear waste. So far, there is no definitive way to get rid of this highly toxic material (although I'm still holding out for microbes that devour the spent rods), so they get buried in thick bunkers underground, so they won't seep radioactive toxins into the surrounding environment, especially the water supply.
Despite this, President Obama notes that there are strong environmental reasons to turn toward nuclear power.
... nuclear energy remains our largest source of fuel that produces no carbon emissions. To meet our growing energy needs and prevent the worst consequences of climate change, we'll need to increase our supply of nuclear power. It's that simple. This one plant, for example, will cut carbon pollution by 16 million tons each year when compared to a similar coal plant. That's like taking 3.5 million cars off the road. (Source: Obama Pushes for More Nuclear Energy)
In a segment critical of the idea, Keith Olbermann tries to drum up some unnecessary drama with a segment highlighting all the worst possible scenarios involving nuclear power, including those based on the cartoon The Simpsons. (Way to go with the hard-hitting journalism.) Most telling is the following excerpt:
Nearly 31 years ago now a partial meltdown at the Pennsylvania plant released 43,000 curies of krypton radiation into the air. I don't really know what that measures and it scares the crap out of me. (Source: Back to the Nuclear Basics)
Maybe, before you go on air to discuss something in front of a few million viewers (assuming MSNBC has that many viewers) you might want to learn what it means. Or you can spread a panic about something which you, admittedly, don't really understand.
Of course, Olbermann did have an expert on the show, but the expert didn't point out that even the two most serious disasters in nuclear power - Three Mile Island (which Olbermann is discussing above) and Chernobyl - have resulted in virtually no long-term environmental break-down. Life comes back in these areas pretty quickly following any sort of nuclear disaster (even Hiroshima & Nagasaki have very little environmental damage at this point), so it's not an environmental question, but one of self-preservation, and a 2002 study even shows that Three Mile Island hasn't had significant impact on cancer deaths over a 20-year follow-up period (No significant rise in cancer deaths in 3-Mile Island residents over 20 years, says Pitt, 2002).
My personal hope is that we won't need nuclear fission reactors, because programs like Europe's ITER project will succeed in developing usable fusion reactors, which leave behind virtually no radioactive waste. But then, I choose to be optimistic.
Find out more about ways of producing energy in our article Sources of Power Production.
