Geek stuff – Page 98 – a sibilant intake of breath

Plants and infrared light

If you have ever seen plants photographed using infrared film, you will know that they have a weird glowing quality when viewed at those wavelengths.

Apparently, the reason behind this has to do with quantum mechanics and photosynthesis. Photons with shorter wavelengths (violet and beyond) have higher energy than those with longer wavelengths (red and beyond, in the other direction). Since only photons with a certain level of energy can be used by photosystems I and II in chloroplasts, plants reflect insufficiently energetic photons, rather than absorbing them. This keeps them from taking in uselessly low energy photons which would simply turn into heat, rather than powering their photosynthetic machinery.

Webs of trust in academic publishing

Public key cryptography was a breakthrough because of the many new types of secure communication it suddenly permitted: most importantly, between people who do not have a trusted channel through which to exchage a symmetric key. Instead, it permits each partner to make a public key widely available, as well as use the public keys of others to encrypt messages that only they can decrypt.

One avenue of attack against this kind of system is for an attacker to make a public key available that they pretend belongs to someone else. For instance, you mighy try to impersonate a government or industry figure, then have people send sensitive materials to you inadvertantly. One way to prevent this kind of attack is to use key signing: an approach employed by both the commercial software PGP and the free GPG alternative. With key signing, you produce a web of trust, in which people use their own secret keys to vouch for the validity of public keys posted by others. That way, if I trust Bob and Bob trusts Jim, I can adopt that trust transitively.

GPeerReview is a system intended to extend this trust function to the review of academic work. Reviewers produce comments on documents and sign them with their keys. These comments can include different levels of endorsement for the work being scrutinized.

It is difficult to know whether the level of academic fraud that takes place justifies this sort of cryptographic response, but it seems like a neat idea regardless. Providing secure mechanisms for people to prove who they are and that things are properly attributed to them is increasingly important as technology makes it ever-easier for nefarious individuals to impersonate anyone in front of a wide audience.

A responsible position on carbon capture

People reading this blog might get the mistaken impression that I am fiercely opposed to carbon capture and storage (CCS) technology. That is definitely untrue. There are few things that would be more helpful than safe, cheap, and effective CCS. It would ease the transition to a zero-carbon global economy, and it would allow for the actual removal of CO2 from the atmosphere, through the growing and burning of biomass.

All that said, it is deeply inappropriate for planners to count emissions reductions from anticipated future CCS in their plans, as the government of Alberta has done to an extreme extent. The technology is in its infancy. Indications to date suggest that it will not be as cheap as its biggest boosters hope. It may not be able to store carbon permanently or safely. Carbon capture certainly cannot do anything to mitigate emissions from mobile sources, making fossil fuel operations that generate fuels for them problematic.

On the basis of these concerns, I suggest that the following elements are important in any responsible consideration of CCS, from a public policy standpoint:

Emissions reductions from CCS should not be estimated until information on the costs and effectiveness of commercial operations are known.
It should not be assumed that CCS will allow high carbon activities such as burning coal or harvesting the oil sands to continue.
While some public funding for CCS may be justifiable (especially investigations into using it with biomass fuels), industry groups that are predicting heavy usage of the technology should bear most of the development and implementation costs.
CCS doesn’t make coal ‘clean.’ Even if it reduces CO2 emissions by 80-90%, coal will still be a climatically unsustainable technology. There are also a large number of environmental hazards associated with coal mining, coal ash, and so forth. Coal will probably never be clean, and will certainly never be clean just because it has CCS bolted on.
Likewise, CCS cannot redeem the oil sands.
We must develop alternative plans, in case CCS proves to be ineffective, unsafe, or unacceptably expensive.

As I have said before, we are in the Wright Brothers era of CCS technology, and it is far too soon to project whether it will be an important stabilization wedge or an expensive flop. It is definitely too early to be estimating the specific quantities of emissions that will be averted by as-yet-nonexistent technologies at unknown future dates.

If emissions are going to peak and descend to safe levels, we are going to need a lot of stabilization wedges: efficiency, protected and enhanced forests, zero-carbon electricity and fuels, and more. If we want to have a strategy that can survive the failure of a few major initiatives, that means we need extra wedges for contingency. As such, we probably can’t reject technologies like CCS and the increased use of nuclear fission out of hand.

Hiding Nobel Prize medals

Recently, I came across an interesting anecdote about the history of Nobel prizes: specifically, those that were awarded to James Franck (for work on quantum physics) and Max von Laue (for discovering x-ray crystal diffraction). Fearful of confiscation by the Nazis, both scientists illegally sent their medals to Niels Bohr in Copenhagen, for safe keeping. Franck then fled from Germany to America, prior to the Nazi invasion of Denmark in 1940.

At the time, sending the medals out of Germany was a very serious crime and, since they were engraved with the names of their recipients, Bohr feared what would happen to them if the medals were found by the occupying army. Fearful that the invaders would find and confiscate the medals, Bohr eventually passed the medals to the chemist George de Hevesy, who subsequently dissolved both Franck and von Laue’s medals in acid (aqua regia, specifically). He was able to hide the resulting black solution from the Nazi invaders and, after the war, the gold was precipitated out of the solution and sent to Stockholm to be re-forged into medals by the Swedish Academy. Bohr had previously sold his own medal at a charitable auction earlier that year.

In 1943, de Hevesy himself won a Nobel Prize in Chemistry, for work on using isotopes to trace chemical processes.

Visualizing power usage

Of late, Google has certainly committed itself to some novel and ambitious energy projects. Their PowerMeter project probably scores fairly low on the scale of ambition, but it could nonetheless be very useful. The idea is to take in data from smart electrical meters on homes and process it into a form, accessible online, that is useful for the people who live in them. It looks like it will resemble the Google Analytics system for website statistics tracking, but it will be concerned with energy usage instead. Ideally, it will be able to isolate electricity usage associated with different activities and appliances, allowing consumers to better understand how they are using power and adjust their behaviour to do so more economically and sustainably.

Particularly when paired with differing electricity prices at different times (in order to smooth out variations between times of peak demand and times of minimal demand), such a system could encourage efficiency, help to balance the grid, and reduce greenhouse gas emissions.

I certainly hope it is eventually made compatible with the smart meters Ottawa Hydro has installing. I have contacted them to ask, but am still waiting for a response.

Walkabout photo kit

My standard set of photo gear for walking around and taking photos has expanded considerably, of late. It now includes:

Canon Rebel XS dSLR
Canon Powershot A570IS
Canon 28-105mm f/3.5-4.5 lens
Canon 18-55mm f/3.5-5.6 IS lens
Lens hoods
Canon 430EX II flash
PC to hotshoe adapter
Sto-fen omnibounce diffuser
CyberSync flash trigger and receiver
Collapsable reflector
Ultrapod mini tripod (for A570IS)
Ultrapod tripod (for Rebel XS)
Polarizing filter
Lens cleaning equipment
Extra batteries (dSLR and AAs)
Plastic zip-loc bag, to prevent condensation when moving from cold to warm places

Among these, the polarizing filter is probably the least used item. The most useful item relative to its price is the Ultrapod mini tripod.

A useful and affordable addition would be a clamp for attaching the flash to things. The addition that I think would be most useful is a 70-200mm lens. It would allow for much better wildlife photography, as well as more capability at concerts and similar events.

Evolution and ‘Darwinism’

In the New York Times, Carl Safina has written an essay arguing that the common conflation of evolution with the work of Charles Darwin is deeply damaging: Darwinism Must Die So That Evolution May Live. There is certainly a good case to be made here. While Darwin’s insights were profound and highly significant, he knew nothing about DNA, patterns of heredity, or the mechanisms of microbiology. Furthermore, it is problematic to associate the work of one person with an entire scientific discipline. As the essay asserts: “We don’t call astronomy Copernicism, nor gravity Newtonism.”

Overall, I agree that the link between Darwin and contemporary evolutionary science ought to be softened. We can recognize the genius of Newton without asserting that his ideas are the be-all and end-all of physics, or optics, or whatever.

At this point in the history of science, we should recognize that evolution has progressed far beyond Darwin. In some cases, his insights have been deepened and expanded through the emergence of new knowledge. In other cases, misconceptions of his have been successfully challenged. The fact of evolution is widely recognized as one of the most important elements for understanding our world – that status is justified regardless of the individuals who most visibly brought the fact to our attention.

The X Files: I Want to Believe

I was unaware that a second X-Files film had been made until yesterday night. On the basis of my first impressions, it was better than the first. It involved fewer outlandish elements, more suspense, more drama between characters, and essentially more of the things that made the television series notable.

I think I managed to miss a big gap in the X-Files canon, though it is possible they simply threw a lot of unexplained material between the first and second films. Unusually for an X-Files production, I didn’t clearly recognize any Vancouver scenery during the film.

The film certainly provided plenty of opportunities for quibbling. For one, one can question whether complex surgery can be performed in a filthy, far-from-sterile environment with any hope of success. Head transplants also don’t have an obvious connection to stem cell therapies. That being said, the aesthetics of those scenes did reinforce one’s natural revulsion towards gross violations of medical ethics.

As an aside, it was strange to see how David Duchovny looks basically the same as he did during the television series, while Gillian Anderson looks dramatically different. It is hard to attribute the latter to natural aging, though perhaps that is the cause.

Avocado trivia

XUP’s blog has a surprising and entertaining compendium of facts about avocados. My favourite among them is the fact that all the animals native to the Americas and large enough to pass avocado pits through their digestive tracts are now extinct – among them, the giant sloths that were of such interest to Thomas Jefferson.

I have generally found avocado tastiest when incorporated into the right kind of sandwiches.

Video on the history of the Earth

Seed Magazine has a neat video up, in celebration of Charles Darwin’s 200th birthday. It condenses the 4.6 billion year history of the Earth into one minute of footage. As such, it gives one a sense of perspective, in terms of how little of the history of life humanity has witnessed.

One quibble: the video refers to photosynthesis by ‘blue-green algae,’ which is a misnomer. So-called ‘blue-green algae’ aren’t algae at all; they aren’t even plants. They are cyanobacteria.