Fire the Maser!

No that’s not a typo.  The maser is the laser’s less cool, older brother.  While laser stands for Light Amplification by Stimulated Emission of Radiation, maser stands for Microwave Amplification by Stimulated Emission of Radiation.  If you remember your electromagnetic spectrum from school, you might wonder what’s the difference, or if the maser is really a specialized laser.  The technical answer is that there isn’t much of a difference.  Masers came around first and really could only work in the microwave spectrum (and actually the first lasers were called optical masers).  Now it’s more complicated, because masers generally emit radiation besides microwaves, and we now have lasers that work outside the optical range of light.  Fun fact:  One idea from decades ago on making the names make sense was to change the letter before ASER for every part of the spectrum, so you’d have masers, lasers, uvasaers (for ultraviolet light), irasers (infrared), grasers (gamma rays), and the incredibly unfortunate xaser (x-ray), which might be unique having both x and s make a /z/ sound with no actual z in the word.

But enough distraction.  I’m supposed to be telling you why masers are the Betty White of the applied physics world and became sexy again after several decades.  Why were masers less cool before?  (Note:  The analogy breaks down here, because Betty White was always cool)  They work by the same mechanism as a laser (that stimulated emission), but weren’t ever as easy to use, either requiring vacuum chambers or refrigeration to a few degrees above absolute zero to work consistently.  While the first few lasers were cumbersome, now they’re small enough to fit in all kinds of everyday devices.  So why the interest in such a frustrating machine?  Because modern technology doesn’t just work in the visible part of the light spectrum.  The whole process of stimulated emission is great at amplifying weak signals, and amplifiers in the microwave/radio range could have a lot of uses in biology and medicine, as well as communications (your cell phone signal is waves in this part of the spectrum).

So what’s new?  In 2002, a group of Japanese chemists published a paper about the energy transitions between different quantum states in several organic molecules.  One material they focused on was p-terphenyl, doped with another organic molecule, pentacene.  “Doping” might sound like a weird word here, but if your first thought is wondering if this is like athletes doping, you’re not entirely off.  In materials science, we “dope” lots of things to improve properties, though currently most of the interest is in electrical properties.  For example, most electronics contain silicon infused with a small amount of boron to add additional charge carriers and provide reliable currents.  Doping works best when the molecules you’re working with have electrons arranged in similar ways.  Although I can’t find an explanation for the exact way pentacene dopes p-terphenyl, I would assume the fact that both molecules are slightly different chains of benzene has something to do with this.  (All the doping I’ve ever heard of has been with elements, so I’m a bit fuzzy on the details of how you dope with molecules.)

Mark Oxborrow from the United Kingdom’s National Physical Laboratory, recently read the Japanese paper and realized the energy transitions that were described could also be used in the stimulated emission process for a maser.  Somewhat amusingly, Oxborrow and his colleagues ended up making a machine almost entirely out of spare parts, including the terphenyl.  However, they were hesitant, because the whole process felt too easy (which seems understandable when you’re working in an area filled with six decades of disappointment).   What finally inspired Dr. Oxborrow to run the maser was an argument with his wife, which encouraged him to go

Even burned, the pentacene-doped terphenyl has a lovely hue

to the lab as “therapy”.  And then he probably needed some additional therapy when the maser exceeded anyone’s expectations:  the signal was a 100 million times more powerful than any known maser.  And he thinks he can do better, because not being much of a chemist, he accidentally burned the crystal while making it.  So here’s to firing more masers.

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On Forgetting that Politics is Weird in Other Parts of the World Too

So this popped up in my news feed on Facebook.  My first reaction was just “What.”  My second reaction is still on-going.  It’s not like Mr. Gumelar is saying Indonesians should ban science from schools; he’s just saying it doesn’t really fit into an elementary school curriculum.  I’m not sure I entirely understand what he thinks should be taught in elementary school (aren’t children going to learn culture and religion from their parents?), but it’s not the weirdest argument to make.  I think the reason I’m confused is because I’m missing context.  The article claims Gumelar is advocating a return to the model of education during Dutch rule over Indonesia which taught only “basic education”, which is never defined.  I am a bit amused that he is worried over the current education system being too Western-valued, but evidently does want the system imposed during colonialism.  (I know nothing of Dutch treatment of Indonesia or the historiography of it, so maybe it’s not as bad as my go-to idea of imperialism would suggest, but still, this seems surprising).  But I agree with the education observer quoted at the end of the article:  it still seems important to expose children to basic science concepts.

Following Up on Algebra and Science Debate

I apologize for the dearth of blog posts.  I plan on explaining myself over the weekend.  But I wanted to point out some new developments on two of the news pieces I’ve blogged about:  pondering the necessity of algebra and wondering if we need a “science debate”.

NPR’s Diane Rehm show recently hosted Andrew Hacker, the author of the “Is Algebra Necessary?” piece, along with a “program supervisor of mathematics” in Montgomery County (I’ve assumed that means he develops math curricula for his school district?),  a Duke economics and public policy professor, and writer/columnist Judy Bolton-Fasman to the show to debate the merits of teaching algebra in high schools.  Hacker rephrased most of his argument.  Unfortunately, Nolan, the math program supervisor, made what I considered one of the weakest defenses.  He merely said the general idea of math builds critical thinking skills without explaining why.  When Nolan said this, Hacker immediately interrupted him and said there is no data proving that math education makes students better thinkers or more active citizens.  This really irked me, because a) I felt that Hacker was incredibly rude for talking over Nolan during his speaking time and b) Hacker himself admits he has no numbers supporting his claim that math is the “number one academic reason” students drop out of school and based it on personal talks with unspecified teachers.  I also think Nolan should point out that Hacker’s “citizen statistics” class would probably fail.  Hint:  Statistics is really confusing without a background in algebra, unless you think statistics is nothing but averages and raw probability values.

Another aside:  There was a discussion on the Diane Rehm Facebook page post about this, and it was interesting to hear some people claim that algebra defenders were being misleading by characterizing algebra as addition, multiplication, division, etc.  You know what I think?  THIS IS BASICALLY ALGEBRA.  Algebra is (mostly) the application of many arithmetic operations in a way to find unknown variables.  So my argument is that if you think algebra I is “too hard” to teach high schoolers, I’m not sure how competent you think they are in mathematics (and I’m not sure they’ll ever be that competent, since algebra I forces you to repeat a lot of arithmetic and would probably improve your skills).

The Washington Post had another follow-up from someone who defended Hacker’s argument about the unnecessary nature of algebra.  Basically, he rips apart all of contemporary high school education.  And I’m totally okay with that.  Although I think high school should at least partially be a liberal education, I can appreciate the idea that people think otherwise.  I’m more annoyed when people single out science and math classes as unnecessary, and yet never seem to realize the arbitrary reasoning for other subjects. (Do we really need everyone to take four years of English?  Can’t we just do a composition class in a year?  Who needs to learn about civics?  You can just read the news if you want to understand government.)  At least here, the author is being honest and just arguing that if none of this works from a cognitive perspective, we should just throw out the whole system.

For the other piece, Science Debate got responses from both the Romney and Obama campaigns!  Go here for the side-by-side comparison and check out their homepage for links to reactions.