Tag Archives: Isaac Newton

Stories from a Race Called Humans

by Shane L. Larson

On a forgotten autumn day long ago, I sat amidst hundreds of strangers in the far-away ballroom of a convention center in Oregon. I was younger than I am now, younger than most of those who were sitting around me. Yet somehow, I had been chosen. I had been waiting. I had rolled that singular moment of time around in my head, over and over again. Out of all the hundreds of hands in the air, mine was chosen, and I stood to ask a question.

My palms were sweaty, my heart raced. I took the microphone, and thankfully didn’t drop it. In those days, I had yet to ever speak in front of more than a small group of my friends in class, but here I was, and damnit I was going to ask my question!  Five hundred pairs of eyes stared right at me, and from the stage, the cool gaze of our guest, encouraging and expectant. I’m sure I squeaked; I must have squeaked. But out came my question: “What is the responsibility of science fiction to bring plausible visions of the future to us?

shatnerThe person I had directed my inquiry to was William Shatner, who had been regaling the crowd of Trekkers with tales of life in the Big Chair, and answering questions about how to properly act out a Star Trek Fight Scene, whether he really thought Kirk should have let the Gorn survive, and whether Spock ever just burst out laughing on set.  And then I stood up to ask my question.

What is the responsibility of science fiction to bring plausible visions of the future to us?

For all the ribbing that Shatner takes for being Shatner, I think he responded in a way that might surprise many people. He smiled, he didn’t laugh. He looked me straight in the eye and told me this: “Science fiction is like all art — it is a medium for telling stories about our humanity. Visions of the future are just stories about us.”  It was a brilliant and thoughtful answer, and I’ve always remembered it.

Now, many years later, I practice science.  I still watch a lot of Star Trek, and I absorb a lot of science fiction, and every time I reach the end of a novel or movie, I know Bill was right — the best stories are the ones that use the future as a backdrop to tell human stories.

lear

Larry Yando as the titular character in the Chicago Shakespeare Theatre’s 2014 production of King Lear.

That’s a very interesting thought when I drape it across the tapestry of art, literature, and theatre. All forms of art are explorations of what it means to be human, attempts to understand on a very deep level who we are. Just this past weekend, sitting in the darkened theatre of the Chicago Shakespeare Theatre, I was bludgeoned by that simple fact once again watching King Lear. Though the story is set long ago, and though the language is not all together our own, we sat there enraptured. The tale is full of intrigue and betrayal, but at the core is the King. Watching the play reflected the dark pools of shadowed eyes, you could see an audience tearfully and painfully aware that the tragedy unfolding from the King’s descent into madness was an all too relevant tale for those of us who have suffered the loss of elderly friends and relatives to the ravages of age.  Our humanity was laid out, naked and bare on the stage, in a tale written more than 400 years ago. The core message is as relevant and pertinent today as it was when the Bard penned it those long centuries ago.

The exploration of the nature of the human spirit has long been the purview of all forms of art, especially performance. The whole point in acting out stories is to tell stories about people.  Even when the characters aren’t people, they still talk and act like people, anthropomorphized by their actions, their thoughts, and their words in the tapestry of story on the stage or screen.  And so I suppose it should not have surprised me that Shatner did not think of tales from the far future any differently — the stories are still stories about us. They still are stories about our triumphs, our tragedies, our frailties, and our fallacies.

But that younger version of myself carried a particular conceit — I wasn’t clear about it then, but I still harbor it today: I fundamentally believe that art and science have exactly the same purpose — to discover the stories of who we are, and what our place in the Cosmos is. The truth of this is hidden in every science book and every textbook you have ever picked up and thumbed through.  How?  Very seldom is science explained without the context, the wrapper, of the human story around it.

Newton witnessed the falling of an apple when visiting his mother's farm, inspiring him to think about gravity. It almost certain is apocryphal that it hit him on the head! But art gives the story a certain reality!

Newton witnessed the falling of an apple when visiting his mother’s farm, inspiring him to think about gravity. It is almost certainly apocryphal that it hit him on the head! But art gives the story a certain reality!

When we are first taught about the Universal Law of Gravitation, very seldom are you simply told the equation that relates mass and distance to gravitational force. Instead, we cast our minds back to a late summer day in the 17th Century. On a warm evening after dinner, Isaac Newton was sitting in his mother’s garden, on her farm in Lincolnshire and was witness to an ordinary event: an apple falling to the ground. A simple, ordinary event, part of a tree’s ever-repeating cycle of reproduction. But witnessing the event sparked a thought in Newton’s mind that ultimately blossomed into the first modern Law of Nature. The tale inspires a deep sense of awe in us. How many everyday events have we witnessed, but never taken the time to heed? How many secrets of Nature have passed us by, because we never connected the dots the Cosmos so patiently lays out before us?

Marie Curie in her laboratory.

Marie Curie in her laboratory.

When we first learn about the discovery of radioactivity, very seldom are we only told the mass of polonium and the half-life of uranium.  Instead, we relive the discovery of radioactive decay alongside Marie Curie, who unaware of the dangers of radiation, handled samples with her bare hands and carried test tubes full of the stuff around in her pockets. We know that she developed the first mobile x-ray units, used in World War I, a brilliant realization of mobile medical technology at the dawn of our modern age. But we also know that Curie perished from aplastic anemia, brought on by radiation exposure. Today, her notebooks and her belongings are still radioactive and unsafe to be around for long periods of time. Curie’s death is a tragic tale of how the road to discovery is fraught with unknown dangers. While we mourn her loss we celebrate also the wonder that our species has such brilliant minds as Marie Skłodowska-Curie, the only person ever to win TWO Nobel Prizes in different sciences (Chemistry and Physics)

Alexander Fleming in his lab.

Alexander Fleming in his lab.

When we learn about antibiotics, seldom do we begin in the lab with petri dishes full of agar. Instead, we are taught the value of serendipity through the tale of Alexander Fleming. In late September of 1928 he returned to the laboratory to find that he had accidentally left a bacterial culture plate uncovered and it had developed a mold growth. You can imagine a visceral emotional reaction — anger! Another days-long experiment ruined! By sheer carelessness! It happens to all of us every day when we burn a carefully prepared dinner, or break a favorite coffee mug, or accidentally drop a smartphone down an elevator shaft. But through the haze of aggravation, Fleming noticed something subtle and peculiar — there were no bacterial growths in the small halo around the mold. The mold, known as Penicillium rubens, could stop a bacteria in its tracks. That single moment of clarity launched the development of antibiotics, so crucial in modern medical care. What world would we inhabit today, if Fleming had thrown that petri dish away in disgust, without a second glance? Surely a tragedy of world-girdling proportions.

All of these stories illustrate a subtle but singular truth about our species: we are different from all the other lifeforms on our planet.  Not in sciencey ways — we have the same biochemical machinery as sunflowers, opossums and earthworms — but in less tangible abstract ways.  What separates us from all the other plants and animals is the way we respond to the neurological signals from our brains. Our brains are wired to do two interesting things: they imagine and they create. The truth is we don’t fully understand how our brains do these things, or why there is an apparent biological imperative to do either. But the result of those combined traits is an insatiable curiosity to know and understand ourselves and the world around us, and an uncontrollable urge to express what we discover.

Sometimes those expressions burst out of us in moments of creation that lead to lightbulbs, intermittent windshield wipers, kidney dialysis machines, and iPads. Sometimes those same expressions burst out of us in moments of creation that lead to Jean van Eyck’s Arnolfini Portrait, or Auguste Rodin’s The Kiss, or Steve Martin’s “Picasso at the Lapine Agile,” or Ridley Scott’s desolate future in “Blade Runner.”

(Top L) Jean van Eyck's Arnolfini Portrait; (Top R) Rodin's The Kiss; (Bottom) The urban dystopia of the future in Ridley Scott's Blade Runner.

(Top L) Jean van Eyck’s Arnolfini Portrait; (Top R) Rodin’s The Kiss; (Bottom) The urban dystopia of the future in Ridley Scott’s Blade Runner.

Art is like science. Imagination expressed through long hours of practice, many instances of trial and error, and moments of elation that punctuate the long drudgery of trying to create something new.  Science is like art. Trying to understand the world by constantly bringing some new creative approach to the lab bench in an attempt to do something no one else has ever done before.

Both science and art are acts of creation with one express goal: to tell our stories. Both require deep reservoirs of creativity. Both require vast amounts of imagination. Both require great risks to be taken. But in the end, the scientist/artist creates something new that changes who we are and how we fit into the world. And wrapped all around them are all-together human tales of the struggles encountered along the road to discovery.

It is not entirely the way we are taught to think about scientists and artists. Isaac Asimov famously noted this in his 1983 book Roving Mind: “How often people speak of art and science as though they were two entirely different things, with no interconnection. An artist is emotional, they think, and uses only his intuition; he sees all at once and has no need of reason. A scientist is cold, they think, and uses only his reason; he argues carefully step by step, and needs no imagination. That is all wrong. The true artist is quite rational as well as imaginative and knows what he is doing; if he does not, his art suffers. The true scientist is quite imaginative as well as rational, and sometimes leaps to solutions where reason can follow only slowly; if he does not, his science suffers.” An interesting thought to ruminate on the next time you are preparing DNA samples or soldering stained glass mosaics.

I have to go now. The crew of the Enterprise have some moments of humanity to show me. See you in an hour.

Gravity does the talking

by Shane L. Larson

Obi-wan Kenobi, in perhaps one of the most famous utterances in cinematic history, claimed that the Force “is an energy field, created by all living things. It surrounds us, it penetrates us, it binds the galaxy together.” This propagated rapidly through popular culture when it was realized that Obi-wan must have been talking about duct tape, which after all has a light side, a dark side, and also binds our world together.

The famous utterance of Ben Kenobi's description of the Force (from "Star Wars").

The famous utterance of Ben Kenobi’s description of the Force (from “Star Wars”).

But an astute citizen of the Cosmos may grow curious at Kenobi’s observation, and ask “what does bind the galaxy together?” As it turns out there is a force that penetrates the fabric of the Universe, in a way it is the fabric of the Universe. We call it gravity.

Many of us have heard the idea that there are four fundamental forces in Nature: gravity, the electromagnetic force, the weak nuclear force, and the color force (the “strong nuclear force” is a faint bit of the color force that “leaks” out of atomic nuclei to be detectable by our experiments). Why is gravity The Force? Why not the others?

The four fundamental forces of Nature emerged after the Big Bang, as the Universe cooled and expanded.

The four fundamental forces of Nature emerged after the Big Bang, as the Universe cooled and expanded.

In order to fill the Cosmos, a force must be a long range force — the Cosmos is a BIG place!  The weak nuclear force and the color force are short range — they act very strongly over very tiny distances, in atomic nuclei and in the nuclear particles that comprise nuclei. The electromagnetic force is a long range force, but it acts in the presence of electrically charged particles, which come in two flavors — positive (+) and negative (-). It is easy to make separate positive and negative charges and to locally generate strong electromagnetic forces (lightning is a prime example from Nature), but by and large the Cosmos is electrically neutral — opposite charges are attracted to each other, and they quickly neutralize and cancel each other out, leaving no free charge behind.  Gravity is also a long range force, but it has only one kind of “charge,” which we call “mass.” There is no negative mass, so gravity cannot be shielded or canceled, and it acts over vast distances.

Gravity is the only game in town when it comes to forces acting on cosmic scales, despite being so incredibly weak.  I can see the skepticism on your face!  I said gravity binds the Cosmos together, and in the same breath said it was incredibly weak!  Whatever do I mean?

I tried as hard as I could to break the apple in two!

I tried as hard as I could to break the apple in two!

I mean that gravity is weak compared to the other forces of Nature, a fact you can easily demonstrate in your kitchen. Pick up an apple.  What is holding an apple together?  It is mostly intermolecular forces between the molecules that make the apple up, and those forces are electromagnetic in nature.  Now,using your bare hands, try to break the apple half.  Not so easy, is it?

Using the chemical energy from some Dr. Pepper, I can overcome the gravitational pull of the entire planet.

Using the chemical energy from some Dr. Pepper, I can overcome the gravitational pull of the entire planet.

Now, stand up and jump up in the air. How high did you get? Even if it was just a couple of inches consider this fact: you were able to momentarily over come gravity.  Using a little bit of chemical energy, gleaned from that rabbit food you ate at lunch (perhaps an apple you ate), you were able to overcome the gravitational pull of the ENTIRE EARTH!  Gravity is weak (and you are strong).

While these kinds of deep machinations are fascinating questions into the deep nature of Nature, you might still be scratching your head wondering what good is this knowledge? The first widely understood law of Gravity was Newtonian gravity, described by Isaac Newton in 1687.  It was used almost immediately to begin describing the motion of heavenly bodies, but by and large the world went about its business more or less oblivious to this stunning achievement of the human intellect.  The practical application of Newtonian gravity, using it for something that humans build or use, was not for almost 270 years: in 1957, the Soviet Union launched Sputnik, requiring a detailed understanding of orbital dynamics, which is derived from Newtonian gravity.  By a similar token, Albert Einstein wrote down the modern description of gravity, general relativity, in 1915. There were immediate applications of general relativity to astrophysics (a trend that has only grown since), but practical applications to human affairs did not seriously arise until the late Twentieth Century.  Let me tell you some stories about how gravity, general relativity, is changing our world.

GRACE.  Our society is engaged in much teeth-gnashing about the nature of the Earth’s changing climate, but most scientists are doing what scientists do best — they put their heads down, they collect data, then they figure out what the data is telling them.  Of particular importance to climate studies is the hydrological cycle on Earth.  Gram for gram, water is a bigger player in thermodynamics than any other substance on Earth. It is extremely effective at cooling and heating, which is why you use it to cool off in the summer and warm up in the winter!  The movement of water on Earth, in the oceans, the clouds, the rivers, and the atmosphere has enormous impacts on climate worldwide.  But the hydrosphere is HUGE! We can’t possibly hope to monitor water levels and water flow in lakes and rivers and oceans worldwide by placing individual sensors.  So how are we to learn about the water on Earth and how it moves and changes?  The answer is we use gravity.

(L) Satellite geodesey monitors the orbit of a satellite to understand the underlying source of gravity. (R) The GRACE geodesey system uses two satellites keeping track of each other using a microwave link.

(L) Satellite geodesey monitors the orbit of a satellite to understand the underlying source of gravity. (R) The GRACE geodesey system uses two satellites keeping track of each other using a microwave link.

Satellite geodesey can make precision measurements of the Earth’s gravitational field. As a satellite flies over the Earth, the changing mass below the satellite changes the strength of gravity, which alters the satellite’s trajectory in its orbit.  We monitor the orbit to know how the gravity (and the mass creating the gravity) is changing!  In 2002, NASA launched a mission called GRACE (Gravity Recovery and Climate Experiment), consisting of two satellites flying about 220 km apart, monitoring each others’ orbit using a microwave signal.  For over 5 years, GRACE monitored the Earth’s gravitational field and was able to see how it changes as water and ice move around our planet.  Just one example is shown below, illustrating how the gravity in the Amazon basin goes up and down with the coming and going of the rainy season.  Similar results illustrate the changing ice around the planet, particularly in the Arctic and Antarctic.

GRACE geodesey is sensitive enough to detect the change in gravity over the Amazon basin as the rainy season comes and goes.

GRACE geodesey is sensitive enough to detect the change in gravity over the Amazon basin as the rainy season comes and goes.

GPS.  phoneGPSPerhaps the most ubiquitous use of gravity in your everyday life is the global positioning system. Once relegated to navigation on planes and automobiles, the advent of GPS built into smartphones has enabled an explosion of location services that allows you to find friends, local restaurants, comic book stores, and concert venues in unfamiliar cities.

Fundamentally, GPS works by triangulation.  Satellites send out timing signals that are received by your smartphone or GPS navigator. The signals are broadcast in synch with one another. This means that if you are an equal, fixed distance from two satellites, you’ll get the same time from both (this is like using headphones — the sound from the L and R side are synchronized so you hear all the right parts of the song and the same time!).  If you are closer to one satellite, then you receive a time from that satellite sooner than a distant satellite (this is like watching a track meet from the stadium — runners hear the starting gun before you do, because they are closer).  Your navigator compares your local time to the time received from the satellites, allowing the determination of distance to each satellite. Since the position of each satellite is known, your location can be computed.

GPS triangulates your location by comparing the received time from multiple satellites.

GPS triangulates your location by comparing the received time from multiple satellites.

The satellite timing signals must be modified, using general relativity.  Why?  The satellites are much higher in the Earth’s gravitational field than you are, and general relativity tells us their clocks tick at a different speed. How much different? Over the course of a day, the general relativity correction to the clock times is about 38 microseconds — 38 millionths of a second!  You may be thinking “But that is so tiny!”  Yes it is tiny, but GPS works based on how far light travels in a given time.  In 38 microseconds, light travels 11.4 kilometers (7 miles)!  When you are trying to find a sushi restaurant, or the soccer field for your kids next game, 11 kilometers is a long way off!

Gravitational waves. ein_1920Let me tell you one last story, not about the practical uses of gravity, but about our dream of using gravity to reveal the secrets of the Cosmos.  In 1918, while exploring the implications of general relativity, Einstein discovered that there exists a kind of gravitational radiation, where the gravity from an astrophysical system carries energy away and into the far reaches of the Universe.  He calculated the strength of this radiation, and very quickly decided that it would be exceedingly difficult (if not impossible) to experimentally measure.

But fast-forward the blu-ray to today, and we have technology at our disposal that Einstein could never have imagined — high precision, high power lasers; GPS positioning systems to accurately locate anything anywhere on the planet; high performance computers capable of performing billions of computations per second; a globe girdling network that passes information from one continent to another as easily as one might shout down the hallway to a colleague; and most importantly, a vast community of scientists well-trained and well-versed in wresting secrets from Nature, the best minds our planet has to offer. You add that all together, and we find ourselves in the land of Einstein’s dreams, poised to measure the faint echoes of gravity bathing the Earth from distant corners of the Cosmos.

Nearly a century of thinking on the matter of gravitational radiation has coalesced around a magnificent machine called LIGO — the Laser Interferometer Gravitational-wave Observatory.  Using lasers shining up and down 4 kilometer long beam arms, a new generation of astronomers — gravitational wave astronomers — hope to detect the dance of neutron stars and black holes spiralling toward collision, the constant drone of young pulsars spinning down into their final rest in the stellar graveyard, and maybe (if we are lucky) the cataclysmic supernova explosion of a star dying, a process that synthesizes most of the atoms that comprise what we are all made of.

The LIGO Observatory at Livingston, LA. There is a companion observatory in Hanford, WA.

The LIGO Observatory at Livingston, LA. There is a companion observatory in Hanford, WA.

Gravitational wave astronomy is a way of asking anew the questions about who we are and what our place in the Cosmos is; it is a way of once again indulging in the unique gift to our species, an insatiable sense of curiosity and wonder.  But are there practical outcomes from this remarkable feat of human imagination? Perhaps not obvious ones, because the practical outcomes were not the driving force in the creation of the experiment. But as with all great feats of science and engineering, from the Manhattan Project to Apollo to LIGO, there are always beneficial outcomes.  Already LIGO’s technology is pushing the frontiers of optics and laser technology, environmental monitoring, and computer network capabilities.  But changes you see in your living room may be 7 or 70 or 270 years away.

This has always been the case for gravity; the timescale is simply a matter of how creative our engineers and scientists get!