Reality Straight Up!

Thoughts & Observations of a Free Range Astrophysicist

It’s Genetic

Returning engineering to its roots

Genetic algorithms are revolutionizing our world by reconnecting engineering with its four-billion-year-old roots.

Republished from my monthly Astronomy Magazine column, For Your Consideration.


I recall the first time that I saw the famous movie of the windy November morning in 1940 when the Tacoma Narrows Bridge, connecting Tacoma and the Kitsap Peninsula across Puget Sound in Washington, tore itself to pieces. There she was, “Galloping Gertie” as the bridge was known, wildly bucking and twisting in a 40 mph (60 km/h) wind. Then, suddenly, in a matter of only a few seconds, the third-longest suspension bridge ever built at the time was no more! To this day, the Tacoma Narrows Bridge remains a textbook example of engineering gone wrong. Structures are subject to vibrations, and if you aren’t careful, those vibrations can spell big trouble.

The spectacular collapse of “Galloping Gertie” in 1940 remains a textbook example of engineering design gone wrong.

Fighting vibrations with a different approach to design

Enter Professor Andy Keane. The year is 1994, and Keane and his colleagues at Southampton University in the UK are working to design a much smaller bridge — a truss — that is as vibration-free as possible. They aren’t worried about the extreme oscillations that destroyed Gertie, but they do care about the slight vibrations that would cripple a delicate instrument like an astronomical satellite. They start with a traditional design, but that’s where tradition ends. Instead of using their knowledge and insight to improve the design in clever ways, they metaphorically throw intelligence out the window. They hand the job over to a computer and then kick back and wait to see what happens.

The computer itself is kept intentionally dumb. It doesn’t know anything about engineering design principles. It only can do two things. First, it can make new virtual trusses by combining and randomly changing the properties of existing trusses. Second, it can compare trusses and tell better from worse. Armed with no other tricks up its sleeve, the computer marches along, blindly turning the crank:

Step 1: Make a new generation of trusses by shuffling and making random changes in the previous generation.

Step 2: Evaluate the new trusses, and toss the ones that don’t work so well.

Step 3: Repeat. Again, and again, and again …

Ten generations and over 1,000 virtual trusses later, the computer’s best effort is lopsided and twisted and irregular. It looks more grown than designed. Nobody understands it or has the faintest clue how it works. But it does work. It works very well. The vibrations have been improved by more than 20,000 percent!

2015-09-Truss

This truss, designed by a genetic algorithm, may not look like much, but it performs wildly better than a traditional truss designed by humans using standard engineering principles. (Photo courtesy Andy Keane.)

When the right conditions are met, evolution isn’t a theory; it is applied logic.

Keane was not the first to take this approach to design, and he certainly wasn’t the last. Two decades later, such unguided, blind algorithms are revolutionizing our approach to the shapes of airplane wings and turbine blades, new molecules for industrial and pharmaceutical uses, pattern recognition, communications networks, investment strategies, cancer treatments, and hundreds of other applications.

At their core, all of these applications have two things in common: (1) the better an item performs, the more likely its properties will be retained; and (2) when surviving properties are passed on from one generation to the next, variations occur. As long as these two conditions are met, properties will evolve from generation to generation as items become better and better suited to their task.

By the way, life satisfies these two conditions. When evolutionary biologists talk about the first condition, they call it “selection.” When they talk about the second condition, they call it “heredity with variation.” And like any other system that satisfies these conditions, life evolves. Logically, life can’t help but evolve! In one sense, engineers who employ genetic algorithms to evolve technologies are doing something new. But in a deeper sense, they are returning engineering to its roots, tapping the power of the mindless algorithm that has been shaping life for almost 4 billion years.

If you want to understand the algorithm of evolution, talk to a cutting-edge design engineer.

The public discussion of biological evolution is undeniably muddled. In part that is because people tend to approach it from the wrong direction. Darwin’s voyage on the Beagle deserves to be the stuff of legend, but if you want to understand evolution, forget about finch beaks or fossils. Instead, talk to a working engineer who is using genetic algorithms to evolve a truss.

Once you’ve wrapped your head around how and why a truss gets so good so quickly, you have the understanding you need to approach evolution as scientists do. You can use that understanding of evolution to make predictions about the world and then see whether those predictions hold true. When you do that, you discover that the predictions of evolution are in remarkable accord with all that we see. From the fossil record to the common chemistry of life, to the shared structure of different species — and now to pharmaceuticals, jet engines, and bridges — we live in a world crafted by evolution’s unguided hand.

The Tacoma Narrows Bridge collapsed because it acted like an unstable airplane wing. If you are interested in the wind-driven resonance (called aeroelastic flutter) that caused the collapse, watch this cool video of a computer simulation from the Natural Hazard Modeling Lab at The University of Notre Dame.


It’s Genetic ^ Returning engineering to its roots  © Dr. Jeff Hester
Content may not be copied to other sites. All Rights Reserved.

Reality Straight Up!

  • Cassandra Smiling  Science, politics and a march in the rainPosted in For Your Consideration
  • EPA Rehash  A suddenly partisan NASA faces its futurePosted in Thoughts
  • The Hermeneutics of  Bunk  Alan Sokal and postmodernism’s black eyePosted in For Your Consideration
  • A Dunning-Kruger Universe  Everyone, it seems, has a “theory”Posted in For Your Consideration
  • Our Need to Know  We crave certainty, even when it is only an illusionPosted in CoachingThoughts
  • A Saguaro’s universe  Building a cactus starts with the Big BangPosted in For Your Consideration
  • Oklahoma Skies  To all the amateurs out there, thanks!Posted in For Your Consideration
  • Fight-or-Flight  How our Pleistocene brains (mis)handle modern threatsPosted in Coaching
  • In a Shark’s Eye  Science and the experience of wonderPosted in For Your Consideration
  • The Quandry of Unpredictability  Chaos, climate and an unpredictable futurePosted in For Your Consideration
  • Why I March for SciencePosted in Thoughts
  • Waiting for Skynet  The benefits of being a machinePosted in For Your Consideration
  • Cassandra Smiling
    Science, politics and a march in the rain

    On a cold day in April, 2017 scientists gathered in Washington DC and cities around the world for the March for Science. Their message was a single powerful idea. Truth is not a political expediency. Reality cannot be ignored. In the year that has followed the vital importance of that message has only grown.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • EPA Rehash
    A suddenly partisan NASA faces its future

    When I look at NASA’s new Administrator, Jim Bridenstine, it is his fellow Oklahoman Scott Pruitt’s EPA that jumps to mind. As politically uncomfortable science is pushed aside, NASA’s history of nonpartisanship appears headed for an abrupt end. Will a strongly partisan NASA have a target on its back?

    Read Article

  • The Hermeneutics of Bunk
    Alan Sokal and postmodernism’s black eye

    Some years ago, NYU physicist Alan Sokal wondered whether anti-science postmodernists could recognize politically-correct-sounding nonsense even if he rubbed their noses in it. The unwitting subjects of the Sokal Hoax jumped at the bait.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • A Dunning-Kruger Universe
    Everyone, it seems, has a “theory”

    Some people are sure they know more than the experts, but it can take a lot of knowledge to realize just how wrong an idea is.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • Our Need to Know
    We crave certainty, even when it is only an illusion

    The human brain craves the sensation of knowing like a drug addict craves the next fix. If real knowledge is uncomfortable or not at hand, we are quite content to just make something up, then convince ourselves it’s real. In a world where knowledge matters, that’s dangerous.

    Read Article

  • A Saguaro’s universe
    Building a cactus starts with the Big Bang

    The iconic saguaro cactus gives the desert an otherwordly beauty. That beauty does not exist in isolation. It embodies the fascinating and awe-inspiring processes that have shaped the universe, going all the way back to the Big Bang itself.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • Oklahoma Skies
    To all the amateurs out there, thanks!

    Looking at room full of amateur astronomers, gathered for the Okie-Tex Star Party under the spectacularly dark skies of the Oklahoma Panhandle, I am reminded of my own roots and those who helped me discover the universe.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • Fight-or-Flight
    How our Pleistocene brains (mis)handle modern threats

    A strong fight-or-flight reaction served our evolutionary ancestors well. If the leopard catches you, that’s it! But today a visceral response to a not-so-mortal threat seldom improves things. If you want to get a handle on those intense, counterproductive bouts of emotion, start by understanding where fight-or-flight came from in the first place.

    Read Article

  • In a Shark’s Eye
    Science and the experience of wonder

    Alone, 100 feet underwater, with a shark in its element, I am overwhelmed by a mixture of awe, beauty, joy, and intellectual wonder at the world that brings us together. In that moment, I experience just what science is all about.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • The Quandry of Unpredictability
    Chaos, climate and an unpredictable future

    Chaos is a sticky wicket for science. There are things a correct theory like climate change cannot predict, but there are a lot of things that it can. It’s important to understand which is which.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

  • Why I March for Science

    On Earth Day, April 22, 2017, people around the nation will March for Science. It seems strange to need to march in support of the idea that pronouncements from politicians cannot change the nature of reality, or that evidence matters when making decisions. But such are the peculiar times in which we live.

    Read Article

  • Waiting for Skynet
    The benefits of being a machine

    For biological organisms, interstellar travel is hopelessly difficult, and probably pointless. For sentient machines, however, home is the environment you were built for.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

    Read Article

Click on thumbnail to select post:

Recent Article Mobile

  • Cassandra Smiling  Science, politics and a march in the rainPosted in For Your Consideration
  • EPA Rehash  A suddenly partisan NASA faces its futurePosted in Thoughts
  • The Hermeneutics of  Bunk  Alan Sokal and postmodernism’s black eyePosted in For Your Consideration
  • A Dunning-Kruger Universe  Everyone, it seems, has a “theory”Posted in For Your Consideration
  • Our Need to Know  We crave certainty, even when it is only an illusionPosted in CoachingThoughts
  • A Saguaro’s universe  Building a cactus starts with the Big BangPosted in For Your Consideration
  • Oklahoma Skies  To all the amateurs out there, thanks!Posted in For Your Consideration
  • Fight-or-Flight  How our Pleistocene brains (mis)handle modern threatsPosted in Coaching
  • In a Shark’s Eye  Science and the experience of wonderPosted in For Your Consideration
  • The Quandry of Unpredictability  Chaos, climate and an unpredictable futurePosted in For Your Consideration
  • Why I March for SciencePosted in Thoughts
  • Waiting for Skynet  The benefits of being a machinePosted in For Your Consideration
  • On a cold day in April, 2017 scientists gathered in Washington DC and cities around the world for the March for Science. Their message was a single powerful idea. Truth is not a political expediency. Reality cannot be ignored. In the year that has followed the vital importance of that message has only grown.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • When I look at NASA’s new Administrator, Jim Bridenstine, it is his fellow Oklahoman Scott Pruitt’s EPA that jumps to mind. As politically uncomfortable science is pushed aside, NASA’s history of nonpartisanship appears headed for an abrupt end. Will a strongly partisan NASA have a target on its back?

  • Some years ago, NYU physicist Alan Sokal wondered whether anti-science postmodernists could recognize politically-correct-sounding nonsense even if he rubbed their noses in it. The unwitting subjects of the Sokal Hoax jumped at the bait.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • Some people are sure they know more than the experts, but it can take a lot of knowledge to realize just how wrong an idea is.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • The human brain craves the sensation of knowing like a drug addict craves the next fix. If real knowledge is uncomfortable or not at hand, we are quite content to just make something up, then convince ourselves it’s real. In a world where knowledge matters, that’s dangerous.

  • The iconic saguaro cactus gives the desert an otherwordly beauty. That beauty does not exist in isolation. It embodies the fascinating and awe-inspiring processes that have shaped the universe, going all the way back to the Big Bang itself.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • Looking at room full of amateur astronomers, gathered for the Okie-Tex Star Party under the spectacularly dark skies of the Oklahoma Panhandle, I am reminded of my own roots and those who helped me discover the universe.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • A strong fight-or-flight reaction served our evolutionary ancestors well. If the leopard catches you, that’s it! But today a visceral response to a not-so-mortal threat seldom improves things. If you want to get a handle on those intense, counterproductive bouts of emotion, start by understanding where fight-or-flight came from in the first place.

  • Alone, 100 feet underwater, with a shark in its element, I am overwhelmed by a mixture of awe, beauty, joy, and intellectual wonder at the world that brings us together. In that moment, I experience just what science is all about.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • Chaos is a sticky wicket for science. There are things a correct theory like climate change cannot predict, but there are a lot of things that it can. It’s important to understand which is which.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

  • On Earth Day, April 22, 2017, people around the nation will March for Science. It seems strange to need to march in support of the idea that pronouncements from politicians cannot change the nature of reality, or that evidence matters when making decisions. But such are the peculiar times in which we live.

  • For biological organisms, interstellar travel is hopelessly difficult, and probably pointless. For sentient machines, however, home is the environment you were built for.

    This article originally appeared in my Astronomy Magazine column, For Your Consideration.

Over his 30 year career as an internationally known astrophysicist, Dr. Jeff Hester was a key member of the team that repaired the Hubble Space Telescope. With one foot always on the frontiers of knowledge, he has been mentor, coach, team leader, award-winning teacher, administrator and speaker, to name a few of the hats he has worn. His Hubble image, the Pillars of Creation, was chosen by Time Magazine as among the 100 most influential photographs in history.
©Dr. Jeff Hester LLC, 5301 S. Superstition Mountain Dr., Suite 104 #171, Gold Canyon, AZ 85118