Time

Art courtesy of Dreamstimes

“Wonder is the source of our desire for knowledge.”                                                     Aristotle

Time is passing.  We know this.  We feel it in our bones.  We hear it in the work of great artists like Shakespeare.  Whenever I give a workshop on time management, the room, virtual or physical, is packed to the rafters.  Students want to know—how does one manage time?  How does one fit all of life into a twenty-four-hour day?

The bottom line:  we don’t manage time; we manage ourselves.  As Carlo Rovelli and Alan Lightman tell us in recent books, time is not constant and is not what it seems.  Time is part of “that vast nocturnal and star-studded ocean of all that we don’t know,” according to Rovelli.

 

In his book, The Order of Time (Riverhead Books, 2018), Rovelli presents the theoretical physics of time and the universe.  He is the head of the Quantum Gravity group at the Centre de Physique Theorique of Aix-Marseille University.  He begins his book with a simple fact:  time passes faster in the mountains than at sea level.  When the Apollo astronauts returned to Earth, they were older than the colleagues they left behind.  This difference might be measured in nanoseconds, but it is there nonetheless.

We do not need to go back to the past to find accelerated aging among astronauts.  A recent study utilizing Scott and Mark Kelly, twin brothers who are also astronauts, revealed that after a year in space, Scott was older than his Earth-bound sibling.  However, after the mission, he quickly reverted back to match Mark.  It took eight months.

Rovelli makes a key point that time bends with gravity or lack thereof.  The closer one gets to Earth, all processes, including aging, are slower.  If one were to travel to the edge of a black hole, the apotheosis of gravitational pull, time would appear to stand still.  Large masses, like planets, slow down time in their vicinity.  This leads to Rovelli’s next point:  planets far away have their own time.  However, it is more than just gravity.  Light travels to us at 186,000 miles per second.  If we were to look across the galaxy at a planet four-light years away from us, what we see through the lens of the telescope would be what happened four years ago.  The way time behaves on that planet would add an additional wrinkle to the scenario.  And this is not just a phenomenon of space; even across the room, we see the person waving at us nanoseconds after the wave because it takes time for the light to reach our eye and the messages to be sent to the brain, and only then is there recognition, and we wave back.

In pop culture, Star Trek, in all its iterations, is where most people encounter the narrative concept of time travel.  The original series began with the voice of Captain Kirk defining the ship’s mission:  five years to explore the galaxy.  But on a five-year journey to the stars, that means five Earth years.  On other planets in other systems, time might be faster or slower.  So an interstellar traveler might return after five years but be 100 years older or five minutes older.  We exist in our own bubble of time corresponding to Earth time.  The rest of the universe moves to its own dance party.  The conclusion is clear:  time is not a constant and not a reliable measure across the galaxy.  The whole question of when, meaning time, is more about where, as in location.  Location and gravity determine time.

Aristotle was the first to ask about the nature of time.  His conclusion was that time is the measurement of change and things change constantly.  Rovelli draws the line between Aristotle’s work and Sir Isaac Newton, who believed time was an entity that runs even when nothing happens.  In the end, what we know is that time is not definitive.  In fact, past, present and future are not clearly delineated in the equations of the universe.  Rovelli brings his thesis home like this:  “the entire evolution of science would suggest that the best grammar for thinking about the world is that of change, not permanence.  Not of being, but of becoming.”  And all of it seems to be moving toward entropy.  Clean laundry starts becoming soiled the minute it leaves the dryer.  A clean house will become dusty again.  It is the law of the universe.  Rovelli says Einstein questioned the concept of past, present and future.  Those designations might only be a persistent illusion.

To read Rovelli is to be both reassured that there is an order to the universe, and to be greatly disturbed at the immense size and complexity that eludes total understanding.  Late in the book, he quotes Hugo von Hofmannsthal:  “Everything slips through our fingers.  All that we seek to hold on to dissolves.  Everything vanishes, like mists and dreams…”

 

Alan Lightman is an American physicist who is both a scientist and a brilliant writer.  His book, Probably Impossibilities (Pantheon Books, 2021), dovetails nicely with Rovelli’s work.  He subscribes to the idea that the universe is moving toward entropy, and he discusses time’s arrow, the “forward direction of time is determined by the movement of order to disorder.”  However, Lightman leaves room for the metaphysical in his study of the cosmos.  He brings to the table the story of his own out-of-body experience where life is “a brief flicker in the vast chasm of time.”   He goes on to write that, “My fleeting sensation included infinite space.  Without body or mind, I was somehow floating in the gargantuan stretch of space, far beyond the solar system and even the galaxy, space stretched on and on.”  He sees in this fever dream himself as a “tiny speck, insignificant,” a sensation that is both “liberating and terrifying” for him.

Lightman emphasizes that we are all composed of atoms.  Our minds are collections of atoms “fated to disassemble and dissolve” at the end of our days.  Yet after we are gone, we remain.  Our atomic components continue on to mix with other atoms and form new life, new structures, always renewing and rejuvenating the universe.  However, our consciousness ends.  Because of that, he has chosen to live in such a way “as to maximize my pleasure and minimize my pain.”  Science becomes life philosophy, and that the value of Lightman’s work in this book.  It is not just science, but a humanist view.  He breaks this down into two schools of thought: the Mechanists who believe that we are made up of processes subject to the laws of chemistry, physics and biology; and Vitalists who recognize a special quality of life, a spiritual force beyond analysis or explanation.  This, then, is the soul, or pneuma, as the Greeks named it, meaning “breath” or “wind.”  It is for the combination of science and spirit that I seek out Lightman.  His work is transcendent and deeply moving for his humanity.  I am comforted by the fact that everyone who has ever lived still remains present at an atomic level.  We are part of everything there is, and in a sense, our atoms are immortal even if our consciousness is not.

This does not stop Lightman from questioning where the dead are now.  This explanation of atoms free-floating through space-time does not assuage his sorrow and longing for those he has lost.  On many days and on many roads, he finds it hard to fathom that they no longer exist and he can no longer communicate with them.  Life is a dream, really, and Lightman cites no less an authority than Emerson:  “Dream delivers us to dream, and there is no end to the illusion.”

This is the dilemma of conscious beings:  we must witness and reflect on the spectacle of existence, even as our own light fades and consciousness dissolves.  This is human truth, but Lightman does not neglect his science.  If space goes on and on to infinity, he posits, there should be an infinite number of copies of us out there.  “Because even a situation of minuscule probability,” he writes, “like the creation of a particular individual’s exact arrangement of atoms—when multiplied by an infinite number of trials, repeats itself an infinite number of times.”

Alan Lightman is a scientist, a physicist, and man who deals daily with star dust and the laws of thermodynamics.  Yet, he is also a man, lying in a hammock, pondering the stars.  Every book he writes is a winner, and this one is no exception.  Following up on his book, Searching For Stars on an Island in Maine (Vintage, 2019), Probably Impossibilities again explores the plight of a human being in the universe.  Along with Carlo Rovelli, the two books give us the science and the humanity, and we are richer for the journey.