Cosmos 2: One Voice in the Cosmic Fugue

by Shane L. Larson

Humanity is simultaneously blessed and cursed with one of the most ingenious creations of Nature: our imaginations.  Our brains have developed not just to run our bodies, and not just to absorb sensory data from the world. They store all the vast myriad of experiences we have and then, at a later time, recall that data for the express purpose of inventing ideas that may or may not have anything to do with reality.

An excellent example of how your brain works can be found in a simple game my daughter and I play at restaurants while we’re waiting for our food.  We call it “The Napkin Game.”  One person draws a simple line doodle, without lifting the pen, then the other person takes that doodle, looks at it from all angles, then adds more lines to turn it into a picture. When you draw a doodle for your partner, you don’t a priori know what it will be turned into.  That’s the magic of brains! Any random doodle could be Batman’s cowl, or a Wonka Bar, or a turtle. Your brain takes a little bit of visual input, maps it onto one of the trillions of neural connections in your mind, and makes something new!

An example of the Napkin Game. One person draws a simple line doodle, and the other person adds to it to make a picture.

One of the most important things your imagination does, is it extrapolates into the future.  Sometimes it makes up extrapolations out of whole cloth that likely have little bearing on reality (though they may be perfectly entertaining, if not desirable, daydreams).  I count among such extrapolations imagined futures where zombies have taken over the world, Apple Slice has made a comeback, or I am close personal friends with Queen Elsa of Arendelle.  But very often, the extrapolations are really simulations — attempts to divine a realistic future. This is the origin of wonder, of anticipation and excitement, and also of fear (particularly fear of the unknown). Imagination uses both of these extrapolations in the game we call science.

The most remarkable thing about imagination is that it knows no boundaries. T-rex flying a fighter jet? No problem. I’m really Walter Mitty, a member of MI:6 who cleans up after Bond?  Duh. Every kind of particle we have ever seen maybe has an undetected and completely made up “super-symmetric” partner particle?  Sure, that sounds cool to think about! 

Examples of imagination, possibly run amok. (L) Dinosaurs flying fighter jets [Lego model; dino added by S. Larson]. (C) The Standard model of particle physics. (R) The “SuperSymmetric” addition to particle physics, imagined by some physicists.

Unfettered by physical limitations or abstract societal rules, our imaginations can stray from the possible to the impossible, from the real to the unreal, and from the mundane to the extreme. The most powerful aspect of this ability is that it allows us to ask questions about things of which we currently are completely ignorant.

Consider the question of life in the Cosmos.  Is there life elsewhere? Are we a singular instance of life, or is there a vast froth of life-filled worlds filling the deep, deep dark of the Universe?

One lonely dish in the Very Large Array (VLA) near Socorro, NM, staring out into the Cosmos. [image by S. Larson]

It is a deep and through provoking question that has profound implications for our philosophical and cultural identities. We can ponder such questions precisely because our brains can take the question and push it to the extreme boundaries, which are:

(1) The Earth is unique. We are a singular instance of the music we call life, a lone voice shouting vainly into the vast, dark cathedral of the stars.

(2) The Cosmos is teeming with life, a vast ecosystem of atoms that have organized into patterns capable of replicating and contemplating their own existence.

Arthur C. Clarke once famously summarized these extremes, saying “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”  The amount we are terrified by this thought is the fault of our imaginations.  We are inherently social creatures — we thrive on contact, discussion, and shared common experience. All of us have, at some point in our lives, experienced profound loneliness — being lost, being trapped, being left out by our peers. When we imagine being alone in the Cosmos, our brain magnifies that sense of loneliness a trillion-fold.  What gets simulated is not the Earth all alone, but ourselves all alone — what if I were alone in the Cosmos, lost in the vast dark? We anthropomorphize the entire human race, mapping our own personal feelings onto 7 billion other souls.

In the opposite case, our imagination proposes a Cosmos completely contrary to the normal hubris that humanity wields.  Despite our proclaimed belief in the fundamental tenets of Copernican astronomy, where the Earth is not the Center of All That Is, we certainly don’t lead our lives that way. Humanity, as a rule, does not pretend to be anything other than the Center of Everything!  But it could be that we inhabit a Cosmos with other intelligences, some perhaps vastly greater than our own, some perhaps implacable and as unaware of us as we might be of ants or bacteria.  Such musings are disquieting because they challenge the central tenet of our perceived existence as the premiere lifeform, on planet Earth or anywhere else.

The question of whether the Cosmos harbors life elsewhere is a compelling one from the perspective of our psychology, but also because there is an apparent conflict between two eminently reasonably scientific viewpoints.  The first of these viewpoints is the so called “Principle of Mediocrity.”  This is the no-holds barred manifestation of the Copernican Principle — there is nothing special about the Earth.  The Cosmos seems to be filled with planets (the latest count, as of today, 9 Dec 2013 is 1051 known planets (visit the Exoplanet Encyclopedia Catalog), with some 3000 candidates from the Kepler mission.  Our deepest probes of the Cosmos (the Hubble Extreme Deep Field) suggests there could be as many as 600 billion galaxies. If each galaxy has 300 billion stars, and every star has at least 1 planet (probably more) then there are a staggering number of possible worlds on which life could have arose. There is nothing special about Earth, so if life arose here, there should be no impediment to life arising on any of the trillions and trillions of other worlds that fill the Cosmos.

The Hubble Extreme Deep Field (XDF). [Credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team]

The opposing viewpoint is something called “The Fermi Paradox.”  It was originally proposed by Enrico Fermi, and can succinctly be summarized as, “Where are they?”  What Fermi wondered was why has the Earth, or any world in the solar system, not been visited by self-replicating robotic explorers of some distant alien race?  His point was that if we really want to explore the galaxy, the most efficient way to do that would be to send a robotic probe out to the nearest star.  It won’t get there in a human lifetime, but it will get there in a time substantially shorter than the age of the galaxy.  When the robot gets to a star system, it pokes around a bit, then builds 10 copies of itself using the natural resources it can find, and sends those copies out to the next 10 closest stars.  If every robot successfully makes 10 copies of itself, it only takes 11 replication cycles before there is 1 robot for every star in the galaxy.  But really, why would they stop there? They would just keep replicating until there are a whole lot of robots in the galaxy.  But we haven’t seen one yet!  Why not? One’s immediate gut reaction might be to think, “Well humans are just the first species to have such a crazy idea. The galaxy is not full of self-replicating robots because we haven’t built them yet!”  But if we apply the Copernican Principle to Earth and humanity in particular, there is no reason to believe we are the first instantiation of intelligent life; some civilization should have preceeded us, and built the fleet of galaxy filling robots.  But there are no robots, and the chance that we are the first civilization in the entire galaxy is vanishingly small.  The fact that there are no robots means that we are alone in the Cosmos. 

Why has our solar system not been visited by alien robots, sailing through to see what the galaxy is full of? This is the central tenet of the Fermi Paradox. [Model by S. Larson]

The space in between these two possibilities is a matter of intense debate among aficionados of the search for extraterrestrial life, as well as professional scientists who spend their careers thinking about this. There are as many facets of the debate as there are persons engaged in the discussion!  In the absence of true, reliable knowledge, our imaginations have free reign. We imagine every idea we can, then argue about whether the idea is plausible or even possible.  One of the most intriguing ideas in this space is that perhaps no civilization ever survives to build a self-replicating army of robots to explore the galaxy. Maybe the Cosmic fugue of life never grows beyond the initial swelling notes of the song.

The dinosaurs haven’t gone (didn’t go?) exploring the galaxy. [Image from Captain Raptor and the Moon Mystery, by O’Malley and O’Brien]

This is not an unreasonable idea. Even if we confine our considerations to the history of life on Earth, we’ve seen “civilizations” that persist for long periods of time. The dinosaurs existed on Earth for 160 Million years, and never developed a single bit of technology (so far as we know), let alone build a self-replicating robot to proclaim their existence to the Cosmos. In the end, the dinosaurs were completely obliterated, wiped off the face of the Earth by an asteroid. Today, their closest living descendants are the birds, but no chicken has reached out to explore the Cosmos either. 

But we don’t even have to think about lifeforms long gone. Even among our own species, entire civilizations have utterly vanished from the world.  Five thousand years ago, the Indus Valley Civilization (IVC) was comprised of 5 million persons, fully 10% of the entire world population at that time. It stretched all along the Indus River valley, in what is today the borderlands between modern India, Afghanistan and Pakistan. The preeminent civilization of the era, the IVC developed the first system of weights and measures; quantitative measure is the foundation of all technology and science.  But they did not colonize the galaxy. The civilization survived for almost two millennia, until the cities were mysteriously abandoned and the civilization collapsed, never having once cast their voice out into the Cosmos. Before they had the ability to build a robot, drought and shifting economics with other, nearby civilizations destroyed the greatest civilization the world had known to that time.

If I were to take these two examples at face value, and use my imagination to extrapolate to other worlds, I might imagine that life is common throughout the Universe, but perhaps it is far too fragile a form of matter to survive. Perhaps it is always obliterated, by the abusive hand of the Cosmos or through ignorance and self-destruction. Obliterated before it can send its seed, robotic messengers, out into the Cosmos.  That would be a depressing thought, with terrifying implications for our future on this world. But it is not inconceivable (even knowing what that word means); even in my lifetime, the spectre of the destruction of our world has constantly loomed, though it has been an evolving chorus of spectres, each sharing the lead.  As a child growing up in the 1980s, the possibility of nuclear annihilation was real and forefront in our minds, even as children. The threat is perhaps no less real today, but the end of the Cold War has reduced the threat in people’s imaginations. Today, the fragility of our climate and environment plays a more prominent role in considerations of what our future may be. Now, as in The Cold War, the conversation is driven by ideology and arguments built around emotional viewpoints rather than scientific considerations. It is not clear we will survive to build a robot army that will explore the galaxy. 

The Earth as seen from Saturn. Can you tell there might be life there from this picture?

Another possibility is that maybe it is just too hard to find other life.  Maybe it is out there, but detecting it is far more difficult than finding the proverbial needle in a haystack.  We are not even sure if there is life elsewhere in the solar system, and we live here! What would an alien robot sailing into the solar system find?  There are almost 100 known worlds in the solar system that are at least large enough to be round (say larger than 200km; list at Wikipedia). Would a robot explore all of them, or simply gaze from afar?  Consider what the Earth looks like from beyond Saturn.  Can you tell there is life here?  Look at the Earth from the Moon.  Can you tell there is life here, especially compared to a picture of Titan from roughly the same distance?  What if the probe never came in this close, landing on the first world it encountered, say Neptune’s enigmatic moon Nereid? 

The Earth (L) and Titan (R), each viewed by a spacecraft from roughly the same distance. Can you tell if either harbors life?

Despite all the difficulties, real and imagined, of searching for life elsewhere, we continue to do it, both by sifting the surfaces of worlds near Earth, as well as plumbing the depths of interstellar space looking for messages from other beings.  The idea of there being life elsewhere is one that is hard to let go of, because the alternative is far too depressing — that we truly are alone. It is a staggering thought, which we are constantly reminded of.

There is a very famous picture of Earth, taken by Michael Collins during the Apollo 11 flight.  As the ascent stage of the Lunar Module Eagle returned to dock with Collins aboard the Columbia in lunar orbit, he snapped a picture showing the Eagle (containing Aldrin and Amrstrong) hanging in front of the magnificent desolation of the Moon, with the partially illuminated Earth in the background.  Collins later remarked,  “I remember most vividly the picture of the lunar horizon and then the LEM ascent stage in the foreground with these two guys in it, and then the Earth popping up at that instant… You’ve got 3 billion people over there, two people here and that’s it.” 

A picture from Apollo 11 of every human being, alive or dead, except for Michael Collins (the photographer). [NASA Image AS11-44-6642]

It is perhaps one of the most poignant images of the lonely Cosmos ever taken — every member of the human race, alive or dead, except the photographer. If indeed we are alone in the Cosmos, then that was everything, captured in a single frame, at a single moment in time.  Every voice in the Cosmic fugue, the chorus of life.

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This post is part of an ongoing series, celebrating the forthcoming science series, Cosmos: A Spacetime Odyssey by revisiting the themes of Carl Sagan’s classic series, Cosmos: A Personal Voyage.  The introductory post of the series, with links to all other posts may be found here:  http://wp.me/p19G0g-dE

Knowing something about everything

by Shane L. Larson

During the early 1970’s, a yellow cab crawled up Park Avenue in New York City. By all accounts, this was an innocuous happenstance, repeated thousands of times a day before and since.  But this cab ride was special, because it gave rise to one of the greatest treaties in human history, the so-called “Park Avenue Treaty.” The signatories were Isaac Asimov and Arthur C. Clarke, who agreed that Asimov was required to insist that Clarke was the best science fiction writer in the world (reserving second best for himself), while Clarke was required to insist that Asimov was the best science writer in the world (reserving second best for himself).  The treaty was famously referred to by Clarke in the dedication to his novel, Report on Planet Three, which read “In accordance with the terms of the Clarke-Asimov treaty, the second-best science writer dedicates this book to the second-best science-fiction writer”.

Arthur C. Clarke (left) and Isaac Asimov (right), the signatories of the Park Avenue Treaty.

The treaty is indicative of one of lost truths of those by-gone days — Asimov was widely regarded as one of the finest communicators of science, though he is most often remembered for his science fiction (if you haven’t read the original Foundation Trilogy, stop reading this now and go find a copy; this blog post will be here when you get back).  He became a proficient and popular science writer in the years after the Soviet Union launched Sputnik, when there was widespread concern about the “science gap” between Americans and the rest of the world (an earlier incarnation of the current growing science gap in our country).  Asimov’s writings were wide ranging, accessible to broad audiences, and enormously popular. Kurt Vonnegut once famously asked Asimov how it felt to know everything.  Asimov replied that he was uneasy with his reputation for omniscience.

Despite his play at modesty, Asimov’s reputation was not ill-deserved.  He was, by all accounts, a polymath — a person whose intellect and expertise span a vast number of areas in the entire body of human knowledge. There have been many polymaths throughout history, many of their names are well known in our popular culture.  Perhaps the most famous, was Leonardo da Vinci, widely regarded as one of the finest mechanical geniuses and artists who has ever lived. Apprenticed as a young boy to the artist Verrocchio in Firenze, Leonardo was immersed and trained in artistic and technical skills of the day: drafting, metalwork, drawing, sculpting, and painting.  Leonardo’s skill manifested itself even at this early age.  Anecdotal stories tell that when he began painting under the tutelage of Verrocchio, the young Leonardo’s skill was so great that Verrocchio swore to never paint again.  In his life, Leonardo produced stunning works of art that have survived and are revered today — the Mona Lisa, The Last Supper, and the Vitruvian Man.  One of my favorites works is the first sketch that we are certain is a work of Leonardo, of the Arno Valley from 1473. It is a simple line sketch that somehow captures the effervescent beauty of that far away Italian countryside, though I have never been there.

“Study of a Tuscan Landscape.” This sketch of the Arno Valley is the oldest known work of art by Leonardo da Vinci.

In my mind’s eye, I imagine the young Leonardo sitting on a grassy hillside, his pen and paper in hand, recording the image of his home in quick lines and shades. As the shape of the Arno Valley emerged and the walls of the Castle Montelupo sprang up on the page, his mind must have wandered in the fertile ground of imagination, exploring new seeds and thoughts planted by the sun and the landscape. Leonardo was not one to let seeds go untended. His genius and creativity are well known, spawning not only some of the most famous works of art in western culture, but also straying to ideas about flight and helicopters, harnessing the Sun’s energy by concentrating it, and the possibility that the Earth’s surface moved (something geologists today call plate-tectonics). No topic was too mundane, nor of little interest to Leonardo. He was a true polymath.

It is a funny fact of human nature that we discourage the behaviour that we so often value.  Polymaths dominate the ranks of the most revered scientists of all time: Leonardo, Galileo, Newton, Huygens, Feynman, Dyson. But in academic circles, polymathism is discouraged. University professors are often encouraged to be narrow minded, to focus their attention and efforts in narrow back-waters of science so they are the world’s single expert in very rigidly defined and narrow boxes of knowledge.  Somewhat surprisingly then, the most awesome applications of human imagination to science are efforts that are highly interdisciplinary, requiring expertise from hundreds of scientists in an astonishing variety of fields.

Approximately a hour to the west of Vinci, on the outskirts of Pisa, one of the greatest miracles of the modern age is taking shape.  Astronomers and physicists, in collaboration with computer scientists and engineers and laser technologists, are constructing an enormous, multi-kilometer long laser interferometer called Virgo (http://goo.gl/maps/CYzrE).  A similar, but smaller observatory called Geo has been constructed in the farmlands outside of Hannover, Germany (http://goo.gl/maps/Ozlco).  The Japanese are constructing another facility called Karga underground at the famed Kamioka Observatory in western Japan.  Two larger observatories have also been built in the United States, called LIGO — one in the high desert of eastern Washington near the Hanford Reservation (http://goo.gl/maps/C1QEj), and one in the verdant cypress forests of Louisiana near Livingston (http://goo.gl/maps/pifQn).

These massive scientific instruments are the cousins of interferometers that have been used in physics laboratories for the past century, simply enlarged by a factor of 4000 and instrumented with state of the art lasers, seismic isolation systems, the world’s largest vacuum system, 30,000 environmental sensors and one of the most powerful linked computer networks ever created for scientific analysis.  The goal is to detect one of the holy grails of physics: gravitational waves.

Gravitational waves are a completely new way of looking at the Universe, not with light, but with gravity.  Virtually everything you know about the Cosmos — everything you’ve ever been taught, everything you’ve ever read in a textbook or seen on the news, has been discovered with light using telescopes.

The Hubble Space Telescope (left) extends our vision deep into the Cosmos, providing views like this one of the Carina Nebula (right), showing us a secret birthplace of stars.

It is a time honored tradition that has passed down to us from another great polymath, Galileo Galilei who built the first telescope in 1609 and wrote about his experiences the following year in the celebrated Sidereus Nuncius (”The Starry Messenger”).  The descendants of that first modest spyglass are simple telescopes you might use in your backyard, as well as the Hubble Space Telescope.  The telescope has taught us much about the Cosmos and our place in it.  But there are new frontiers to be explored by changing our perspective.  The detection of gravitational waves will revolutionize our understanding of compact astrophysical systems. We will be able to directly probe the interior structure of neutron stars (the densest objects known) as they tear themselves apart in titanic collisions; we will watch black holes merge and ringdown, revealing their size and spin; we will see stars plummeting in chaotic spiraling orbits around black holes that will map out the gravitational field to reveal the structure and shape of the hole.  And, if we are lucky, we may even detect the faint echoes of gravitational waves from the Big Bang, whispers across time from an era 400,000 years earlier than any ordinary telescope will ever be able to see.

It was Einstein himself who discovered the idea of gravitational waves in 1916, but he almost immediately discarded the notion of detecting them because the physical effect that has to be measured was, in his estimation, beyond our abilities. Fast-forward to the modern era, and technology has changed.  Not just a single technology, but many technologies.  The instruments we build to detect gravitational waves are a complex synthesis of ideas requiring people of broad mind and discipline.

The enormous arms of these interferometers had to be laid out by our best construction contractors, because the arms are long enough that the curvature of the Earth matters!  The 1 meter diameter vacuum pipes had to be manufactured then spiral welded without any leaks or cracks over the entire 4 kilometers of the instrument arm.  Thermal engineers had to design expansion baffles on the beamtubes that contract and expand with the heating and cooling of the arms with the rising and setting of the Sun. Seismologists and meteorologists and electrical engineers had to create a network of some 30,000 environmental sensors that monitor and report on the health and environment of the observatory.  Exquisite isolation engineers had to build suspension systems capable of filtering out vibrations from everything — people walking down the hall, the echoing tremors of ground motion on the other side of the world, and the rumble of car tires on a highway ten miles away.  Computer scientists and network engineers have designed a computing and data acquisition system that has thousands of individual links, stores and processes data, and delivers that data to a collaboration of nearly 1000 scientists spread around the world.  Master optical engineers and laser physicists have built a laser injection and control system that takes as input a single infrared laser beam, circulates it over 1600 kilometers during 400 trips up and down the vacuum beam line, and brings the laser light all back together to measure minuscule changes in distances that herald the arrival of gravitational wave signals from remote corners of the Cosmos.

LIGO is an awesome machine, whether you are looking down one of the 4 km arms (left), or staring into the guts of the computer system interlinking the instrument and all of its vast sensor network (right).

Standing at the vertex of one of these great instruments, staring down the arm to the distant end stations 4 kilometers away, it is easy to be amazed by the ingenuity of our scientists and engineers — large teams who have butted heads, argued, designed, tested, and ultimately built the most sensitive scientific instruments our species has ever created.  A pool of talented people who had the where-with-all to imagine every possible problem that might be encountered along the way and design a solution.  Talented people who encountered unforeseen problems, ferreted out the cause of the trouble, then built a solution that allowed us to continue down the long road toward discovery.  These great machines, and ultimately the discoveries we make with them, are a testament to their dedication and perseverance, a legacy as great as that of Newton, and Huygens, and Leonardo.  We polymathed our way to these instruments, not through the intellect of a single person, but through the linked abilities of a vast team of people spanning multiple decades of work.  As a result of those efforts, we find ourselves poised on the brink of discovery: breathless with anticipation, and rightfully proud of our accomplishment.

The LIGO-Hanford interferometer, seen from the air.

Standing at the vertex of LIGO, one can’t help but be overwhelmed by two things. The first is the awe-inspiring example of what we can engineer through sheer ingenuity and perseverance. Instruments like LIGO will fundamentally change the way we view the Cosmos, pushing us to look beyond the simple prejudices imposed by the limitations of our physical senses and listen to the grandeur of a Universal symphony we’ve never been able to hear before. The second is that this machine is only the beginning of so much more than just astrophysics. New technology and new insights always flow back to society and are used in startling and unexpected ways, propelling our young species forward. This was true with Apollo, and as many others have pointed out, is true for LIGO.  The LIGO laser technology is already making its way into the carbon composites industry where it is being used to test aircraft parts. Einstein@Home (like it’s big sister, Seti@Home) was one of the first projects to use your home computer to do scientific crowd-computing while your computer was sitting idle during Monday Night Football, turning the world into a vast supercomputer. LIGO’s advanced laser control systems are demonstrating the precise methods needed to shape and control lasers in applications ranging from laser welding, to high precision laser cutting systems, to advanced laser weapon systems.  None of this was intended, but it all sprang from the same fertile ground — the seeds of ideas planted and nurtured from an exquisite mix of ideas stirred together with reckless abandon.  Polymathism in the large.

Standing at the vertex of LIGO, staring down the arm, the joy in our accomplishment is pierced by an unerring certainty that we should be doing more of this.  We need more polymathism in the world, on scales both large and small.  We should unfetter our young scientists, and let their minds stray to the far reaches of wonderfully crazy ideas and fantastic imaginings about what our future could be.  It is hard to imagine that good things can and will result from allowing such freedom, particularly in trying times of economic woe and political discord.  It is even harder for the vanguard of scientific leaders (the “greybeards”, as I call them) to encourage big expansive thinking among our young scientists when the great discoveries could easily overshadow our own seemingly meager contributions to the state of human knowledge; the egos of scientists (despite their outward bravado) are fragile. But that doesn’t change the fact that we need more polymaths, not just to inspire us by charging down the frontiers of discovery, but to address serious problems with new and creative connections and solutions that narrow box thinking will never discover.  The world has serious problems, and we need creative thinking to address those problems.

Standing at the vertex of LIGO, staring down the arm, I wonder what Leonardo would have thought if he was right here with me?  I can imagine him sitting here next to me, with a parchment and a pen in hand, sketching the long lines of LIGO’s arm, the scrub desert of eastern Washington and the distant shadow of Rattlesnake Mountain, and my mind strays into imagination, wondering all the things that could be.