Twisting Perspectives: A Case for Technological Optimism
Part I: Positivity in Principle
This past week began as any other. Driving to work on Tuesday morning, I threw on a podcast from somewhere deep within my backlog. It was an episode of Mindscape, a podcast hosted by Caltech theoretical physicist Sean Carrol. The episodes tend to be interviews or conversations featuring guests with a wide variety of backgrounds. This week the guest was Ramez Naam, formerly a computer scientist at Microsoft, currently a technologist and science fiction writer, and a self-proclaimed renewable energy optimist. If you’re interested in hearing a compelling case for why you should be more optimistic about the future of renewable energy globally, I’d recommend you give the episode a listen! I’ll leave the details to the experts, but the main topic of conversation was that technological advancements will drive us, as a species, toward more environmentally-friendly energy sources as a matter of economics, not necessarily of principle. It’s no secret that the price of renewable energy has been plummeting as our understanding of the basic science and of scaling technologies has improved. In fact, we are just now reaching the point where renewable energy is at parity, cost-wise, with energy produced from the consumption of fossil fuels. At a certain point, it simply won’t make financial sense (exempting government subsidies) to continue to generate power using fossil fuels. By the time I arrived at work, I was in a much better mood than when I had started driving. Maybe we aren’t doomed to inhabit a fiery wasteland in the future, after all!
In today’s media climate, it is easy to allow the sheer volume and character of breaking news to dominate your state of mind. You wake up, have breakfast, and maybe browse the internet on your phone for a few minutes before heading out the door. During that time, you’re bound to come across a dozen stories cataloguing our most recent transgressions against the environment, some new unspeakable abuse of human rights, or else corruption exhibited by elected officials, either locally or abroad. This crushing burden of bad news can sow pessimism in even the most sprightly and optimistic of individuals, and it’s no surprise. It seems unlikely that our cognitive machinery was designed to process all the woes of the world, presented to us anew each day. It’s just too much. It gets one to thinking; what is happening in the world? Are things getting worse, or is it simply that we are more interconnected than ever before?
Good morning! New York Times World News 10/19/19
Serendipitously, the next podcast I listened to later in the week addressed this very issue. This time, is was an episode of Sam Harris’ Making Sense Podcast, with guest Andrew McAfee. Andrew is a research scientist at the MIT Sloan School of Management, and has authored a number of books discussing how digital technologies are changing our way of life for the better. The conversation focused on the relationship between technology and human prosperity. For the full discussion, you’ll want to check out the podcast yourself, which again I must highly recommend. Andrew does not shy away from our rough treatment of the environment, focusing particularly on the Industrial Revolution in the United States and the enormous rate of resource consumption, pollution, and species extinction that accompanied it. This incredible rate of consumption paved the way for our massive leap forward in technological capability, and made possible the quality of life improvements that followed. It is clear that things are not perfect in the modern world; domestic issues such as wide political divides, middle-class wage stagnation, and wealth inequality continue to dominate our (Western) collective psyche, all the while massive global human rights abuses linger in the background. Geopolitics notwithstanding, Andrew argues that today is actually the best time in human history to be alive, referencing massive improvements in life expectancy and other quality of life metrics over the past 100 years. Even more promisingly, Andrew then goes on to discuss how we are now entering an era where individual and societal prosperity is continuing to increase, despite the fact that our rate of resource consumption is decreasing. The main thesis being that as our technological capabilities continue to grow, we are simply able to do more with less.
What a difference 60 years can make! Improvements in air quality are evident in these two photos of Los Angeles City Hall, the top from 1958 and the bottom from just last year. (Associated Press, Nigel Killeen/Getty Images)
Part II: Uncovering Reasons for Optimism in Your Own Life
Of course, it’s one thing to be told that technology is paving the way to a brighter future, and another to internalize this worldview and personally believe that there is some reason to be optimistic in the face of the many overwhelming challenges that we face as a species today. In this second part of my post, I’d like to recount a recent experience in my own life that validated this way of thinking for me.
Toward the end of the same week that I listened to these two podcasts, while reading a reference paper for a project that I’m working on, something caught my eye. The paper was titled Role of the Electron Spin Polarization in Water Splitting, and it detailed an exciting development in the realm of hydrogen fuel generation from the oxidation of water.
Some quick background for those of you a few years removed from your last chemistry class: water may be split to produce gaseous oxygen and hydrogen (energy + 2H 2O -> O 2 + 2H 2) if a sufficient potential is applied to the system. Unfortunately, water splitting is not necessarily a straightforward process, requiring significant overpotentials (additional potential on top of what is thermodynamically required for the process to occur) and often hosting a number of competing reaction pathways, particularly in the formation of undesired hydrogen peroxide, which limit the efficiency of the splitting process. The splitting of water is a topic of intense research at the moment, due to its promise to enable large-scale production of hydrogen as a fuel source. Hydrogen gas, once produced, may be employed in a fuel cell as a source of energy, operating in the reverse of the splitting reaction (O 2 + 2H 2 -> energy + 2H 2O). In this way, hydrogen is an exceptionally clean fuel, producing only water as a byproduct of its consumption. If you live in California, you’ve likely seen people driving hydrogen-fueled vehicles already, or at least seen their fueling stations. This article from CNBC does a good job of outlining why we should take hydrogen seriously as a fuel source.
A schematic of a hydrogen fuel cell. Hydrogen gas is fed into the cell, oxidized at the cathode, then moves through the electrolyte barrier and reacts with oxygen gas at the anode to produce water. The electrons generated by the oxidation of hydrogen gas move through an external circuit before finally reaching the cathode and being consumed in the formation of water. This electric current is used to power whatever apparatus the fuel cell is integrated within.
In the paper I mentioned above, the authors found that the overpotential required for water splitting could be reduced by simply coating the anode of the cell (the electrode where water is being split), with short DNA molecules, approximately 13 nanometers in length. That’s about 1/10,000 ththe width of a strand of hair. We are all familiar with the iconic double helix structure of DNA. This helical structure imparts DNA with a specific kind of symmetry known as chirality.
If you’re unfamiliar with the concept of chirality, here’s a quick example to get you oriented. Hold your hands in front of you. Your right hand is a mirror image of your left. Try as you might, there is no way that you can rotate your right hand in space to make it indistinguishable from, or superimposable with, your left. To visualize this further, put your left hand out in front of you, palm facing up. Put your right hand, palm facing down, on top of your left hand. Your right hand now has knuckles facing up and your left hand knuckles facing down. The fact that we have knuckles imparts our hands with this special symmetry; they are chiral. If we did not have knuckles (or fingernails), you would note that it would be impossible to tell your hands apart when placing them palms together (though I suppose in this scenario you wouldn’t have palms either). Contrast this to something achiral (without chirality), like a pair of glasses, or a coffee mug. Take the mirror image of one of these objects and you will see that it can easily be superimposed on the original. Achiral objects are indistinguishable from their mirror images.
A typical example of chirality. There is no way to orient the left-handed molecule in space such that is overlaps completely with the right-handed molecule. Although each of these molecules is made of the same stuff, they will behave differently in important ways.
Returning to the case of DNA, a right-handed double helix is non-superimposable with a left-handed double helix (the mirror image of the right-handed helix). Chirality gives rise to a number of interesting chemical, optical, and electronic properties. Roughly 20 years ago, in a seminal paper published in the journal Science, the research groups of Professors Ron Naaman and David Waldeck demonstrated that molecules of one handedness will preferentially conduct electrons based on their spin (a quantity analogous to intrinsic angular momentum). This behavior, known as chiral-induced spin selectivity (CISS), has important consequences for evolutionary biology, atomic-level electronic/spintronic device design, and, as it turns out, fuel generation (I will explore the former topics in a subsequent post).
So how does chirality relate to the production of hydrogen fuel? As it turns out, oxygen molecules produced in the splitting of water prefer to exist in triplet states. A triplet oxygen molecule (O 2) is one in which both atoms of oxygen have unpaired electrons with their spins aligned. As I mentioned previously, spin can be pictured as the intrinsic angular momentum of an electron. If we picture an electron as a solid sphere with a charge (-e), then the spin of the electron would be exactly that, the direction in which the sphere is spinning around its own axis. Of course, electrons exhibit wave-particle duality and so this simplification rapidly falls apart in reality, but it’s a good visualization tool. Due to the CISS effect, electrons of one spin are preferentially conducted through a chiral helical DNA molecule. In the context of water splitting, this means that water molecules that come in contact with a DNA coated electrode will preferentially transmit electrons of one spin over those of another. For a water molecule to split, it must donate two electrons. If these electrons are donated through a DNA molecule, their spins will be more likely to align, meaning that those unpaired electrons left behind in the molecule will themselves be aligned. This residual spin alignment allows triplet oxygen to form more readily, thereby lowering the overall energy barrier to water splitting.
I understand this might all seem a little underwhelming, especially if you’re not a fan of chemistry. However, it’s really quite amazing to consider the big picture. By coating one electrode within a water-splitting cell with a film of tiny DNA molecules, the overall efficiency of hydrogen production can be increased dramatically. More than that, this increase is simply due to the symmetry of the molecule. If we were to unwind the DNA, the energy barrier to water splitting would once again increase. This struck me as an incredible example of the smallest of differences leading to a measurable and positive outcome. If something as small as the twist of a molecule can have such far-reaching consequences for clean fuel production, imagine what other secrets and advancements lay dormant, waiting to be discovered by the next generation of intrepid and inquisitive explorers?
For me, reading this paper while sitting at my desk on a cloudy evening like many others, the themes that Sean, Ramez, Sam, and Andrew were discussing suddenly seemed to strike home. It is undoubtable that we (collectively) face many real and imposing obstacles ahead, some of which at times seem just about insurmountable. Still throughout all of this, it is important to observe and appreciate the small victories, to marvel at the incremental improvements wrought by those with the perseverance, knowledge, and yes, optimism, to believe that forward progress, no matter how inconsequential to others it might seem, is necessary to bring about a better future. Remember, just as the air above LA wasn’t made smog-free in a week, similarly it will take time, hard work, and a whole lot of belief if we are to overcome with the most pressing and formidable challenges of our time.
At the end of the day, it is up to the individual to make a judgment call on their rationale for optimism. What purpose does it serve in your life? What are you good at, passionate about, or willing to contribute to? Do you see examples of work or progress in your daily life that impress you or that lead to positive outcomes for those affected? How can you make a difference regarding an issue that you care about? Have you read anything recently that has given you a reason to be optimistic? If so, please consider sharing!
Originally published at http://dominikstemer.wordpress.com on October 20, 2019.
