Seismic vibrations of the heart

You should be able to see three heartbeats on the bottom line (labled Z), though the Z obscures part of one of the waves.

We were working on plate tectonics last week, and the conversation went from earthquakes to heartbeats.

I think it started with the question of, “How do we know what the inside of the Earth is like if no one’s been down to see it?”

I agreed that we’ve not even been down to the bottom of the crust because the heat and pressure would collapse any hole we tried to drill. I did not mention that terrible movie, “The Core”, because beyond maybe the first ten minutes where there is some actual speculative science fiction, it’s really not worth seeing.

But beneath the crust, how do we know how thick the mantle is? How do we know that the inner core is solid metal (mostly iron) while the outer core is liquid metal?

Not wanting to go into too much detail I tried to explain about seismic waves. Different types can go through different materials and if you monitor their reflections off different parts of the Earth’s interior you can puzzle out the layering and composition. I just gave the simplest demonstration: if you tap a piece of wood with you knuckle, could you tell that it was wood and not metal? What if you tapped a bucket, could you tell if it was full of water or not? Well seismic tomography work in much the same way, except that you’re usually picking up the reverberations from the earthquake rather than making it yourself by hitting the bucket. There’s also a bit more math involved.

But tapping the bucket gives a quick easy feel (pun intended) for the process. My students at least seemed satisfied.

So then I pointed out that you could use an app called iSeismo, to detect seismic waves. Both the iPhone (and its variants) and the iPad have accelerometers that can be used to pick up motion in all three dimensions. My students from last year remembered it, and at least one already had it loaded on his phone.

A quick test showed that the phone’s pretty sensitive. You can pick up two people jumping together all the way across the room. This part of the demo is nice because it helps prove that seismic waves from earthquakes can go very far. You can also see the little squiggles as the waves are picked up.

I did not try it this time, and I’ll need to confirm if it will work, but since the time on the phones should be well synchronized over the network, and iSeismo can output the actual data, we should be able to use three iPhones to triangulate the location of the jumpers. This might work in nicely with geometry now that I think about it.

Checking for a heartbeat using iSeismo.

Anyway, finally, a student asked if the phone might be able to pick up his heartbeat if he lay on his back.

We tried it. Lying on his back on the floor while holding his breath, we could see his heartbeat quite clearly.

The Economy and Revolution

Vali Nasr’s interview on NPR’s Morning Edition talks about what it takes to make a successful revolution. Particularly, they focus on the need for a vibrant, educated, middle-class for a successful transition to democracy.

Another key, and I think essential point, is that the Egyptian protesters share the same global-citizenship values that Brazilians, South Koreans, and even Europeans and American, share. That they have these values, from years of communication with the outside world, offers the best chance that this revolution will be successful.

Edmund Burke supported the American Revolution, but opposed the French Revolution because the former was a conservative revolution, the colonists were fighting to regain rights that had lost, while the latter were trying to impose an ideal of democracy and equality that they had no experience with. He was right; the French revolution lead to the Terror then eventually to Napoleon and the restoration of the aristocracy.

Haiku by an economist

Economist Stephen T. Ziliak’s reflections on poetry are quite appropriate for the moment, since we’re doing both poetry and economics this cycle.

Invisible hand;
Mother of inflated hope,
Mistress of despair!
–Stephen T. Ziliak: Haiku Economics

Zilak says that, “Poetry can fill the gap between reason and emotion, adding feelings to economics.”

He particularly loves the haiku, because it is such a wonderful metaphor for economics: “less is more, and more is better.”

Each poem is the length of about one human breath. This constraint, though severe, is more than offset by a boundless freedom to feel.
–Stephen T. Ziliak: Haiku Economics

Creativity is said to lie at the intersection on disciplines. This is an excellent example of it.

Global Warming Refugees

NPR’s Brian Reed has an excellent two-part series on the small island nation of Kiribati‘s preparations to adapt to global warming.

Kiribati. (Map from the U.S. Congress via Wikimedia Commons).

Small island nations are the most sensitive to the effects of global warming. Rising sea levels will substantially affect places where the land is just a few meters above sea level. But small islands also have limited capacity to adapt to significant changes.

These articles tie in to our questions of modern migration, which we discussed last cycle (C3) and environmental change.

[googleMap name=”Tarawa Island, Kiribati” description=”Tarawa is the capital of the Kiribati Islands” width=”480″ height=”480″ mapzoom=”10″ mousewheel=”false” directions_to=”false”]Tarawa Island, Kiribati[/googleMap]

Counting syllables

If you need a little help finding how many syllables are in a word so you can use it in your haiku, there’s the How Many Syl.la.bles website.

Screen capture from the How Many Syl.la.bles website (Grade Level Technology, 2009).

It also suggests related words if you need a differently-syllabic synonym.

Where disciplines meet
creativity emerges
from the shaking chrysalis

How protests lead to revolution

The events that spark revolutions can come as a surprise. While everyone at home might want to overthrow the dictator, they don’t know if everyone else wants to do so too, so they are reluctant to go against the government. This is why protests are so important (as well as news coverage of the protests), because then the people offended by the government can see that there are a lot of other people like them.

Dictators, like Mubarak, do a lot to prevent protests: their secret police will arrest and “disappear” opposition leaders; riot police will be out in force to suppress protests if people start to gather.

The Egyptian protesters faced this very problem. So they organized over the internet, as anonymously as possible, and, for the January 25th protests, they arranged several meeting places for protesters so the riot police were too spread out to suppress everyone.

Stephen Pinker talks about this in terms of Individual Knowledge and Mutual Knowledge. Individually everyone knows the dictator is bad, but with the protests, they all realize, mutually, that everyone else also thinks the dictator is bad. Which is really bad for the dictator.

How to memorize a poem

My students are working on poetry this cycle and I’m having them each memorize and present each of the different types of poems we’re covering.

Jim Holt suggests memorizing poems slowly over time:

… the key to memorizing a poem painlessly is to do it incrementally, in tiny bits.
— Holt (2009): Got Poetry?

But I very much like John Hollander’s advice to use the rhythm of the poem to help with memory:

It is partly like memorizing a song whose tune is that of the words themselves.
–Hollander (1995): Committed to Memory

Another approach, which worked for Michael Weiss, was to type out pairs of lines in a word processing program.

It may take about ten repetitions before a couplet is committed to memory, but as you gain experience, they’ll come faster than that.
–Weiss (2009): How to memorize a poem

All of the essays cited above also make persuasive arguments for why anyone should memorize poems. Ultimately, it comes down to the fact that poems in memory are readily available for reflection. You get a feel for the rhythm and musicality, and you get to look at the words in different ways as you turn them around in your mind, playing with their meanings.

Finally, my students have become pretty good at presenting poetry, partly because they’ve seen Shake the Dust, but mainly because of our doing poetry every morning. Good presentations in the past have ratcheted up the quality of the presentations we’ve been seeing.

We’ve already started on haikus, but next week my students will be presenting sonnets. So far, things look promising.

Nix the Monster

A recent study making the news today, warns about the risks of energy drinks. 30-50% of adolescents and young adults drink them, they have lots of caffeine and other additives, and they do not have a whole lot of benefits.

Energy drinks have no therapeutic benefit, and many ingredients are understudied and not regulated. The known and unknown pharmacology of agents included in such drinks, combined with reports of toxicity, raises concern for potentially serious adverse effects in association with energy-drink use.
–Sara Seifert et al., 2011: Health Effects of Energy Drinks on Children, Adolescents, and Young Adults

Applying the precautionary principle might be in order.