Saddling the Future

August 22, 2014 in Responses

Life is said in many ways. – Aristotle, De Anima

Bruce Sterling confronts the reader with the problem of verticality—the dizzying heights of ascent with its slow release from warm temperature and gravity and oxygen and a protective ozone layer. Height has been a long looming quest for humans. In the opening volume of his A History of Religious Ideas, Mircea Eliade begins by explaining that everything changed for us humans once we could walk upright with our spine like a tower pointing upward and defying gravity. Verticality became tied to spirituality. We conscious and self-aware beings rose up over and against nature around us.

In “Tall Tower” the dusty Western old-timer Cody Jennings and his trusty steed Levi attempt a new feat of verticality—they will ascend the Tall Tower. The story intimates that humans have ascended the tower that reaches to the stars and then reached beyond it; humans have propelled their consciousness into outer space and in the process become superhuman. Sterling draws this notion of a superhuman consciousness from the present day transhumanist movement. Transhumanism believes we can reach technological capacities that will allow us to leap beyond human limitations of mortality and organic brain-limited intellect. There are many permutations of how transhumanists believe this will happen, but essentially in a cybernetic union humans will off-load or mesh their consciousness with self-aware artificial intelligence. We will live inside smart computers only not “inside” since we will be these beings.

Sterling’s story is framed by the haunting questions: if humans can become superhuman in a techno-spiritual leap, what about animals? In other words, what will happen to Cody’s faithful beast Levi? This seemingly innocent question is actually a devious device. Depending on the reader’s viewpoint, the problem of Levi either challenges transhumanism to include other animals or it deconstructs the transhumanist idea by claiming that what it means “to be” for humans and for other animals is to be as flesh and blood, as a body.  In contrast to transhumanism, a movement called posthumanism asks us to take account of animal being—including the human animal—over and against reason and technological progress which favors humans. What would a superhorse look like? Would it have greater consciousness or greater animal strength or both? And just as we have breed modern horses with their proficiencies could we breed superhorses?

Technologies often help humans overcome limits of our animal being. With our technologies we can lift more, move farther and faster, see more, etc. Yet domesticated animals are also technologies; the horse helped us settle the Wild West. What is the West without the horse—and cattle and dogs for that matter? But these animals are more than technological machines—horses are not just horsepower. As Cody and Levi ascend the Tall Tower, their quest is a way of asking what is the body to humans and what is the role of animals in the civil world? Equipped in space suits like postmodern knight and steed, Cody and Levi seem like Quixote and his horse who tilted the technology of that time, windmills. Tilting windmills, ascending towers, is this a spiritual quest or physical exertion? Or is it both since through exerting bodies perhaps we find something spiritual? Since the time of Aristotle in his De Anima (On Life) humans as rational beings were considered superior to animals since, as the Greek philosopher proclaimed, we have rational souls. Yet, it is Levi (a name echoing a chosen people) who carries Cody on his journey. Could Aristotle and a Western tradition of human exceptionalism be wrong? Is there room for animals in the leap forward, and what will happen to human and animal bodies—do we need them to be who we are?

 Ron Broglio is an Associate Professor in the Department of English and a Senior Sustainability Scholar at the Julie Ann Wrigley Global Institute of Sustainability at Arizona State University. His research focuses on how philosophy and aesthetics can help us rethink the relationship between humans and the environment.


Sharing the Fire

August 22, 2014 in Responses

When Thomas Jefferson wrote about the American imagination, he chose the metaphor of fire. Ideas should flow like light in the darkness, “as he who lights his taper at mine, receives light without darkening me.” Jefferson was one of the original American dreamers, a man with many faults but also an explosive mix of creativity and ambition. His passions ranged from gardening and architecture to the framing of constitutions and he doubled as our first patent officer and secretary of state.

Jefferson and the other founding fathers knew that the new republic needed to balance optimism and pragmatism if the experiment was going to last. The separation of powers and the Declaration of Independence toe a line between human folly and human progress: a belief that the world can become better, but that its improvement and its stewardship depend on us.

You might say that the spirit of thoughtful optimism has infused some of our greatest achievements. The Internet and the Apollo missions were born out of nuclear anxieties and Cold War paranoia but transformed those impulses into startling victories for the species. Living out Jefferson’s language, they lit up the globe, igniting the imaginations of billions.

In recent years, the spirit of thoughtful optimism has struggled to overcome the challenges of political infighting and cultural malaise. When we do contemplate big thinking today, it’s almost never something to take on personally. Instead we rely on well-funded entrepreneurs and major corporations to do our dreaming for us, content to wait for the new update or the latest sequel to appear and make us marginally happier, for a while.

That kind of thinking has gotten us a world obsessed with incremental improvements in a few key areas while we ignore entire systems that are stagnating, crumbling, or just destructively churning along. We have spent untold billions in researching a few high profile diseases while hardly bothering to invest in new antibiotics or basic preventive medicine—drugs that actually work aren’t as profitable as those that merely treat the symptoms. We agonize over gas mileage improvements while hundreds of new coal-fired power plants open around the world. The people who are changing the world either invest massive amounts of their own capital, like Bill Gates, or they perform end runs around existing social structures in order to achieve specific goals, like the X Prize Foundation.

It’s not that we’ve forgotten how to change the world. Barack Obama did it in 2008. Mark Zuckerberg did it when he founded Facebook in 2004. This year NASA landed a one-ton machine on Mars with automatic piloting.

But what we’re missing is a sense of collective agency, a shared narrative of the American dreamer. We need to recognize that nobody is going to build the world we want but us.

We think thoughtful optimism means recognizing that putting a man on the moon and building better social systems here on earth are equally challenging and equally important. It means better stories about sustainability and justice as well as artificial intelligence and space vehicles. When we say imagination we don’t just mean that initial spark of a new idea—we’re talking about the human engine that keeps at the problem, adapting tools and creativity to build complete solutions. We’re not interested in “somebody should invent that…” but rather “we can do this better.”

Ed Finn is the founding director of the Center for Science and the Imagination at Arizona State University, where he is an assistant professor with a joint appointment in the School of Arts, Media, and Engineering and the Department of English. He has worked as a journalist at Time, Slate, and Popular Science. He lives in Phoenix, Arizona.

Structural Design of the Tall Tower

August 22, 2014 in Responses

The challenge of building tall structures has lured people like me into the profession of structural engineering for a long time. Managing our gravitational well in order to elevate usable space above the surface of the Earth is harder than it looks. And it’s not just gravity holding us down. The ebbs and flows of that thin sheet of fluid that is our atmosphere and ground shifts caused by tectonic movement create a difficult physical environment for building tall.

Despite training for the moment for my entire career, I was a bit stunned when Neal Stephenson asked me if a 20 km tall tower could be built. As a structural engineer I was still basking in the glow of the achievement of the Burj Khalifa—the current world’s tallest building standing 830 m tall. The notion of creating a structure 25 times taller than the tallest structure in the world was at odds with the gradual increments that have long characterized the evolution of tall buildings and long bridges. What? Do that next?

Neal had been inspired by a speculative paper from about a decade earlier—written by scientist and science fiction writer Geoffrey Landis—that claimed a tower 15 to 25 km high could be built from steel. A tower of that height could double the payload to orbit of a conventional rocket, he argued. The proposal that Landis had made appears to have been based on the assumption that, at a given level, the structure need only provide vertical resistance to the accumulated weight of the tower and payload above it. Engineers basically manage force by increase resisting area to reduce stress. In essence, Landis had proposed a vertical column with cross sectional area large enough to keep the stress below the available strength of the material. The weight of the resisting material gets to be a large part of the load. If you add material to reduce stress you also add to the cause of that stress. The result is an exponential cascade of material from top to bottom. Steel is strong, but it is also heavy. This simple model suggests that the total weight of material required is W = P (eµ – 1), where P is the payload at the top and µ = ρh/σ is the ratio of the density times height to the strength of the material—a sort of characteristic number of the tall tower. So the weight of material is basically the payload multiplied by a factor that gets exponentially large as the height goes up. If you want to carry no load then you need no material. One key engineering challenge is to figure out what P should be. How much does Cape Canaveral weigh? The Burj Khalifa weighs 0.5 million tonnes empty. So to put the Burj Khalifa up on top of the tower would require about 5 million tonnes of the best steel you can get. The upshot of these “back of the envelope” figures is that the 20 km tower seems very doable. That might have been the inspiration of Landis’s comment that the tower would be easy to achieve with today’s materials.

The simple Landis model gives us a baseline number for what it might take to realize the tower, but it ignores the lateral forces caused by wind and the possibility of the tower buckling under its own weight. To have lateral stability the tower must have bending resistance. Now, not only is the area of material important, so is its distribution. The tower needs girth.

The main design problem is to determine the shape that minimizes the weight of material while providing adequate strength. We narrowed the design space by considering symmetric towers with circular plans because we had no good reason to assume that the wind would blow in a particular direction, but we allowed for the possibility that the radius of the tower could vary with the height. The tower would need to have a wide base to resist overturning, but should be narrower in the upper reaches to project a smaller area in the most intense winds.

The tall tower will extend into the jet stream—a wind environment far more demanding than any we design for on the surface of the Earth. Some data indicated that the wind velocity would peak at about 90 m/s at about two thirds of the way up from the base. The wind load model we adopted was fairly primitive, but included the variation of air density with height along with the variation of wind velocity. The force on the structure is the accumulation of the forces on each member of the structure. We sought a design that would catch the least wind, narrowing the neck of the tower in the most intense portion of the jet stream.

While some data are available on winds in the troposphere, it is generally not tailored to what a structural engineer needs to know. It is a basic truth of structural engineering that the structure will be exposed to the environment all of the time and probably for hundreds of years. There is no instant in all of that time that can be passed off as insignificant. The structure will have to bear it all and while the most intense loads might be rare, the likelihood of occurrence over the lifetime is significant and the consequence of being unable to meet the demands that nature serves up are dire.

To advance the design at a more refined level, we developed a reticulated model, grafted some of the shape assumptions from the simpler models, and added a simple optimization engine to keep the stresses below allowable levels for the material for each member. Even at this more refined level the model blurs many details. Neal had always imagined that the tower would need to have a “fractal” structure (like the Eiffel Tower). What that means is that the tower would comprise mega-members that would be made of smaller members (laced together in some sort of trussed configuration) and those smaller members would be made of members smaller yet. And so on until the members that you actually build with can actually be made (and lifted). One consequence of the fractal geometry is that not all of the material can be oriented in the optimal direction (e.g., vertical for vertical loads). Some of the material must be invested in bracing—the members must be tied together to transmit the forces of wind and gravity over the structure so that it can mobilize its structural resistance.

For the reticulated model we created a design that would allow a variable number of levels (like stories in a tall building except that each “story” in the tower is about the height of the Burj Khalifa) and a variable number of primary columns. We imagined the plan as concentric circles to give the tower a “wall thickness.” At each level we created a truss ring that would transfer the loads at that level across all of the primary columns. The tower radius builds from a broad base (covering about 25 km2 in recent designs); it tapers in the region of the jet stream and blossoms at the top to provide usable real estate. With a four-sided geometry the tower looks a lot like the Eiffel Tower (except for the flair at the top)—an inevitable consequence of the forces it must resist. For a given geometry we optimized the structure with an algorithm that simply put more material in areas where stresses were high and took away material from areas where the stresses were low. Hence, for a given geometry we could find the minimum amount of material required. A recent design suggests that we are in the neighborhood of 250 million tonnes of steel—a healthy fraction of world annual steel production.

The truss geometry provided a sort of “level-zero” layout of the fractal structure, but it did not explicitly model all of the additional fractal levels. For a tower with twenty levels there are about a thousand members. In a fractal structure each member replicates the geometry of the larger structure. Therefore, modeling at the next level of the fractal geometry would have a million members. One more fractal level would give a billion members. An investigation of the fractal nature of the structure revealed an important result—as the number of fractal levels increases the wind area of the members also increases unfavorably. While the fractalization allows the wind to “blow right through the structure” it traps wind on the way in and on the way out. The fractalization thins out the members but there are more of them and member stability requirements at the smallest level determine the exposed fractal area. The implication of this observation is that the main members would likely need to be enclosed in a sheathing to reduce the wind drag. The demands of the wind have fostered interesting speculation about whether or not it is possible to use aerodynamics to help mitigate the wind induced stresses. The wind could be employed as a passive system that mobilizes uplift when needed most.

At present the tower is conceptualized only at the level of broad brush strokes. The design of the tower has opened areas of fundamental inquiry into the nature of the jet stream and the nature of air flow around and through fractal structures. Many design questions remain. A method of construction is yet to be devised—it is difficult to imagine the traditional steel worker toiling at minus 60 Celsius in air so thin that a Nepali Sherpa would be left gasping. That paradigm will need to give way to a robot-based approach (or perhaps even more clever strategies). The foundations of this enormous structure will bring unprecedented challenges to geotechnical engineers. What about transportation? Imagine a train system spiraling around the exterior of the tower. Imagine an airport two kilometers above the surface of the Earth.

It is evident that the lightest structures have the coarsest fractal geometry. But the horizontal bracing members at the first level of a twenty-level tower with five sides are longer than the longest bridge span in the world today. Each member will be a monumental record-shattering design in its own right. We still have to figure out how to do that. And the details are mind-numbingly complex. The basic geometry of how the members come together to form a structural joint capable of transmitting the huge forces is a challenge. A strategy for joining the members to form the structure is not solved and is made more complicated by the very cold temperatures in the upper reaches of the structure. And questions about the integrity of the structure in the event of an attack or natural disaster remain unresolved. The ordinary strategy of adding redundancy brings enormous additional weight.

This journey to wrap my mind around the possibility of the tall tower has caused me to recalibrate nearly everything I have ever thought about building tall. Along the way, every time my engineering sensibilities said “no” I would struggle back to “why not?” The idea is just big enough to keep you from trying to extend what has been done just a little bit further—it is an idea big enough to drive new thought.

Is the Tall Tower possible? Yes, theoretically. Is it feasible? Who is to say? That is more a question of human will than anything else. We still await the flood of ideas for use of the tower, and therein lies the case for building it. Oh, and by the way, if you put more stuff on the tower we will need to increase the size a bit.

Hjelmstad on Stephenson – Structural Design of the Tall Tower

Hjelmstad's research focuses on computational mechanics, earthquake engineering, stability of structures, optimization, structural identification, nondestructive evaluation of large structures, and numerical simulation of complex structures. He is a member of several professional associations for engineers and serves as associate editor of the Journal of Constructional Steel Research and the ASCE Journal of Structural Engineering.

Response to “A Hotel in Antarctica”

August 10, 2014 in Responses

What did you like best about Geoffrey Landis’ story “A Hotel in Antarctica”?

First, I liked the interplay between the different types of characters that were there. You had the young entrepreneur, you had the seasoned veteran, you had the operationalizer, you had the environmentalist, and there’s some curve balls with those characters. Some of the things that you’d expect them to do, they did, some of the things you expected them to do, they didn’t. So I really appreciated that sort of landscape of characters. Second, I liked the dialog between the idea of human entrepreneurship, our interaction with physical spaces and our ability to experiment our way into the future.

As a sustainability scientist, what elements of the story seemed realistic, or made you think of things that will be happening in the real world soon?

Oh, yes. A hotel in Antarctica is quite realistic as it is! It’s not far-fetched at all. We push into every environment there is on the globe; a hotel in Antarctica is not that different from a hotel in the Amazon, and we’re doing that. There are more and more people climbing Mount Everest today; it’s become like a train.

Also, if you think of sustainability as people impacting planetary systems – climate change is an example of this – human activities are having a real, measurable impact on the global climate. The hotel in Antarctica is a real metaphor for that. You’re taking a bunch of human beings, you’re putting them in this extreme situation where they are bounded by environmental reality, and they are trying to make a place for people to survive and succeed. Of course, it doesn’t quite go the way that anyone expected, and it turns out that the external world, Mother Nature, throws down a few trump cards. But then other people come to the rescue and then we try to muddle our way through it and survive. All of those pieces are very realistic and there are examples of all of them happening right now, either metaphorically, on a grand scale, or quite specifically. We’re doing it now. I wouldn’t be surprised if I looked at The Guardian tomorrow and was a hotel being built in Antarctica.

I think that one of the most realistic messages in the story is that the separation between humans and nature is a fiction. People want to go out into nature, so you can’t conserve nature by blocking it off from people. Also, people are part of nature. When you can change your environment like we can, you’re not separate from nature. You’re a part of it. Anything we do in terms of conservation, or in terms of all of the other activities we undertake as humans, those things are embedded in nature, so we have to figure out a way to make that interconnectedness work. That’s true whether you’re an environmentalist or an entrepreneur.

How can science fiction stories like this one help inspire real-world innovation and research?

I think that engaging with science fiction can improve scientific innovation and research on three levels.

First, science fiction helps us expand the boundaries of what scientists are thinking about and helps let the imagination be a bigger part of our scientific studies.

Second, science fiction provides a landscape for technology, or human interactions with different systems or technological innovations, to be rolled out, so we can see the implications of what we are doing in the lab. Science and innovation can be transformative forces, so it’s important to have vehicles that let scientists and citizens think through the implications of new research and innovation. Science fiction is also nonthreatening, and as is the case with “A Hotel in Antarctica,” it can also be entertaining and enlightening.

Third, science fiction provides a medium for conversation across different fields. Anyone can read “A Hotel in Antarctica.” You don’t have to be a PhD in Physics to like Star Trek. So it provides a place for scientists and everybody else to have conversations and discussions, and share their excitement around these topics. “A Hotel in Antarctica” is near term; it’s today-science-fiction. It can provide a nonthreatening space to have a conversation about topics like the future of conservation, or what this particular human-nature interface looks like. What happens when you take a bunch of hairless apes and try to stick them in Antarctica? What happens when you do it in the Amazon? Or at the bottom of the ocean? A story like this can provide a comfortable, cross-cutting landscape for the conversations that we really need to have.

George Basile is a Senior Sustainability Scientist at Arizona State University’s Julie Ann Wrigley Global Institute of Sustainability and a Professor of Practice at the School of Sustainability. His research focuses on green business practices, strategic leadership on sustainability issues, and biotechnology.