Thursday, May 30, 2013

Simons Lecture at Brown University, September 24

Mathematics of Planet Earth 2013

MPE2013 Simons Public Lecture by L. Mahadevan

On Growth and Form:
Mathematics, Physics and Biology

L. Mahadevan

L. Mahadevan, Harvard University

September 24, 2013 at 6:30 p.m. at Salomon Center, Brown University
Speaker: L. Mahadevan, Harvard University
Hosted by: Institute for Computational and Experimental Research in Mathematics (ICERM)
Sponsored by: Simons Foundation

(This posting brought to you via MPE2013.  Read the rest of the announcement here.)

Monday, May 27, 2013

ACMS Conference Talk Preview

In a couple of days I'm off to Bethel University in Minnesota for the biennial conference of the Association of Christians in the Mathematical Sciences, whose purpose is "to encourage Christians in the mathematical sciences to explore the relationship of their faith to their discipline".  As a young scholar in Oxford I found the mere existence of the ACMS a great encouragement. Even though I hardly expected to meet any other members (I think there was a time that I was the only one in the UK), it was good to know that others were wondering, as I was, how the "aha!" of mathematical insight and the steamroller power of logical reasoning fit with the confession that "all things hold together" in Christ (Colossians 1:17). 

In due course I moved to the US and met some of the ACMS people (such as Bob Brabenec, whose vision the whole thing was, I think) and this year they were rash enough to elect me to their board. Much of the ACMS's membership is drawn from faculty at Christian colleges, but, remembering my own experience, I expect that there are also many "Christians in the mathematical sciences" in industry and government and secular academia who could find encouragement in the ACMS and bring new perspectives.  If this is you (undergraduate or graduate student, researcher, teacher, or skilled user of mathematics) feel free to get in touch!

Anyhow, I will be giving a short talk on Thursday at the conference entitled  "Creation Care As a Focus for a General Mathematics Course."  Regular readers will know that I'm putting together a Mathematics of Sustainability course which I hope to teach at Penn State soon.  But I feel that the themes of that course are, if anything, even more suitable for a math course at a Christian college or university.  The phrase "integration of faith and learning" gets used a lot at these institutions, meaning that faculty and students are charged to take seriously the verse I quoted from Colossians above - "all things hold together in Christ" - and to try to make its implications precise in the context of their specific academic discipline.  It's easy to imagine that professors of mathematics find this more challenging than some of their colleagues!  In my talk I want to suggest that the theme of "creation care" or "creation stewardship" provides an excellent perspective on such integration.  On the one hand, it is deeply linked with big theological questions about creation, redemption, and the nature of hope; on the other, its is linked with essentially mathematical questions about scale, change, randomness and connectivity.  That's my pitch, for which I have 15 minutes.  I'm looking forward to it!

Friday, May 24, 2013


High above Yosemite Valley, I've just descended to a set of rappel anchors - two bolts set in the rock, solid and secure but looking very small amid the shimmering granite extending above me, below me, to the left and to the right.

I get ready to lean back on the anchors and pull the rope to set up the next rappel. Before doing so, though, it's always good practice to eyeball the system one last time, to make sure that the set-up is correct.

Time contracts. Bile rises.  Then a long, slow exhale.

I had not been clipped in to the anchor.  Lean back confidently, like so many times before, and I would go a thousand feet to the talus below.

Sunday, May 19, 2013

Careless and Crazy?

The Heidelberg Catechism is a central confession of faith for Christians in the Reformed tradition.  As a "catechism", it is presented in question-and-answer format, and at #60 it pops a critical question: How are thou righteous before God? The answer: Only by a true faith in Jesus Christ, and the following questions and answers emphasize that righteousness or 'justification' is a grace-gift, unearned, unmerited, undeserved - simply received.

Then comes #64:
  •  Question: Does not this doctrine produce careless and crazy people?
If grace can only be received and not earned, won't this remove any incentive to ethical behavior?  Why not do evil that good may come? - as Saint Paul was apparently accused of saying. Or, to revert to the ecological theme of this blog, why bother with trying to preserve and restore "nature", since "grace" will come soon enough and overwhelm it anyway? Of course remarks like those recently attributed to Mark Driscoll ("I know who made the environment and he's coming back and going to burn it all up - so, yes, I drive an SUV") feed into this picture of "careless and crazy" believers.  Having written about this incident myself, I'm glad to acknowledge that Mr Driscoll has, to some extent, walked these comments back.

The same "careless and crazy" question underlies another recent news item: an article in the Political Research Quarterly (Barker, David C., and David H. Bearce. “End-Times Theology, the Shadow of the Future, and Public Resistance to Addressing Global Climate Change.” Political Research Quarterly 66, no. 2 (June 1, 2013): 267–279) which argues that "religious belief could slow global warming action" because believers in the Second Coming of Jesus see the planet as "ultimately doomed" and therefore work with a shorter time horizon than nonbelievers who have "little reason to doubt humankind's infinite persistence" (sic).

The authors' theological understanding is pretty unsophisticated -  they tell us that "for Christian traditionalists... the planet has no future", and, as a proxy for this "disposable planet theology" they survey people about whether they believe "that Jesus will return to earth someday".  Apparently they are unaware that a belief "that Jesus will return" is no novelty, but one affirmed by all of the ancient creeds of the Church.    As a result, I'd guess that they significantly overestimate the prevalence of "disposable planet theology", but potentially underestimate its influence on those who actually do hold it. 

But those gaffes don't let believers off the hook.  Do we act careless and crazy? Or do we act blessed and thankful? Does not this doctrine produce careless and crazy people?  "Truly a full-blooded doubt" comments Barth (Evangelical Theology, chapter 11).  So, in our stewardship of creation, let's live out the answer:
  • Answer: No. It is impossible for those grafted into Christ through true faith not to produce fruits of gratitude.
  Public domain image from Wikimedia Commons

Monday, May 6, 2013

Manly Environmentalism

Mark Driscoll, the pastor of Mars Hill Church in Seattle, is in the news today for remarks he apparently made at a conference in Dallas.  Reportedly, he commented:
 I know who made the environment and he’s coming back and going to burn it all up. So yes, I drive an SUV.
It's not an uncommon argument in some Christian circles - though seldom stated so crudely - and I've already written about it on this blog.   The two-point summary of my previous posting is:
  • The coming judgment does not mean that what we do now is of no account - quite the contrary!
  • The creation is to be restored, healed - not junked!
And one could also add
  • The New Testament emphasizes that the timing of "that day" is completely unknown (Matthew 24:36-44), so we cannot use its imminence as an excuse not to take thought for our children and the generations to come.
(In a recent poll only 14% of American Christians gave the scripturally correct answer "I don't know" to the question "Will Jesus return in the next forty years?". )

But what also interests me here is how Mr Driscoll continued his remarks.  After presenting his SUV-driving credentials, he reportedly said
If you drive a minivan, you're a mini-man
Environmental concern, it appears, is for wimps: the potent SUV is a sacrament of masculinity. (Women are entirely absent from the discussion.)  How ironic that this news item should make the rounds the same week Niall Ferguson told us that Keynes couldn't take thought for posterity because he was gay

I think there is more than bad theology at work here.  By driving the SUV (or by buying the incandescent bulb), I assuage my anxiety, I reinforce my ("manly") identity against a perceived threat.  What is that threat? Perhaps it is the threat of relationship, of being enmeshed in mutual dependence.  To attend to ecology is, inter alia,  to become aware of how deeply our lives are connected to those of other humans, animals, plants, and the rest of creation.  Is this insight unwelcome to Mr Driscoll?  Is the return of Christ important to him chiefly as a razor-sharp knife that enables him to cut that entangling relational web?

Image from Stuff Christian Culture Likes.

Wednesday, May 1, 2013

Solar Wishful Thinking

You might have seen this picture, which is making the rounds on Facebook (with a link to an article at "A portable solar-powered outlet that sticks to any window", says the caption.

Cute gadget.  But let's do some estimates of how much power we might get out of it.

The intensity of bright sunlight is about 1000 watts per square meter. Assuming those two pins have a standard spacing, the diameter of this gadget is maybe 4-6 centimeters, so the area is about 12-18 square centimeters. That gives less than 2W incident radiation when oriented normal to the sunlight (the most efficient direction - less otherwise). Solar cell efficiencies are maybe 20%, so the available power is a few tenths of a watt under optimum conditions. If the gadget really contains an inverter as well (so producing AC power at the outlet) there will be further losses there. 

Let's be super optimistic and suppose that we get half a watt out of the device.  What could one do with that?  Not run your microwave or your hairdryer or your laptop, that's for sure.  According to, a single rechargeable (NiMH) AAA battery stores 3400+ joules, so it would take about two hours to recharge from this device.  The battery pack for a typical small electronic device might be four AAA cells, so think about all day to recharge it.

It's a pleasant fantasy that we can stick a simple device to the window and get power for free, but in reality, energy is not floating around our environment in so concentrated a form.  Of course that is why, when we did discover really concentrated and (temporarily) abundant forms of energy - coil, oil, uranium - we were able to make such drastic changes to the environment.  Abundant energy was "a story for which the world is not yet prepared", like hunter-gatherers suddenly introduced to Haagen-Dazs.

PS: Sherlock Holmes fans, what was the story for which the world is not yet prepared? No Googling!