Will the Human Spirit Survive for Billions of Years?
Since the instant that Galileo Galilei looked through his telescope at the sky, Astronomy was based on detecting light from the cosmos. The hot cosmic gas glowed early on, and we detected the radiation it emitted in the form of the cosmic microwave background.
Afterwards, the cosmic gas condensed into galaxies — inside of which it fragmented into dense clouds that gave birth to luminous stars. When a star is born, the temperature at its core exceeds millions of degrees and so the fuel of hydrogen and helium starts to burn. Clusters of these nuclear fusion reactors are observed in the form of galaxies all the way to time when the Universe was just hundreds of millions of years old. This offers scientific details to the biblical story of genesis: “Let there be light!”, which I summarized in two textbooks here and here.
The debris disk of material left over from the formation process of the Sun included heavy elements that condensed in the disk midplane to make dust particles that stuck together to make rocks that coagulated to make rocky planets like Earth. There were many more Earth-size planets in the early Solar System and most of them were ejected through gravitational slingshot by Jupiter or other planets. The surviving planets are on stable orbits, but we know that shortly after the Earth formed — it likely collided with a Mars-size planet and shed some mass that gave birth to the Moon. The duration of a day on Earth was lengthened from about 4 hours early on to 24 hours today, as the Moon receded and stole the Earth’s rotation into its orbital angular momentum. Within 7.6 billion years, the Sun’s envelope might engulf the Earth-Moon system and cause the Moon to crash back on Earth as a result of its drag on the envelope’s material.
Everything around us keeps changing and as a young technological civilization, we need to learn how to survive in our turbulent cosmic neighborhood. Attending to lessons learned by advanced civilizations that survived for a longer period of time could guide us about the best strategy for our own survival.
Observing the large scales of the cosmos endows us with a sense of cosmic modesty, but it also offers us a global perspective on the death of everything we get emotionally attached to. Over the cosmic timescale of billions of years, the best we can hope for is to rise to the level of an interstellar or perhaps an intergalactic civilization that started its life on a small rock near a common star but chose to be cosmologically ambitious despite all odds against its longevity.
It is unclear whether this is truly our destiny or just my wishful thinking. At any event, my hope is that by finding siblings from our family of intelligent civilizations who survived, we will be inspired to imitate them. Finding them will also provide us with an emotional connection to the Universe, far more powerful than the deterministic dynamics of matter and radiation described currently by our incomplete cosmological equations.
Here’s hoping that the human spirit will ultimately prevail over all challenges imposed on it by our cosmic circumstances.
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In this essay, I featured four amazing watercolors from a series created by the celebrated artist, Greg Wyatt. These watercolors incorporate inspiring statements by Giordano Bruno, Cicero and Johannes Kepler. This is the seventh in a sequence of essays, where Greg and I collaborate on the interface between art and science. The first essay in this series, titled “Music of the Cosmic Spheres,” appeared here; the second essay, titled: “Cosmic Waterfalls in Spacetime Cliffs,” appeared here; the third titled “Missing Elements in the Cosmic Jigsaw Puzzle,” appeared here; the fourth essay, titled: “Why Do We Exist?”, appeared here; the fifth titled “Inspiration from the Stars”, appeared here; and the sixth titled “We Might Understand How the Cosmos Works Before We Understand How Life Works”, appeared here.
ABOUT THE AUTHOR
Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
Professional website:
https://lweb.cfa.harvard.edu/~loeb/
Social media:
https://avi-loeb.medium.com/
https://www.youtube.com/@ProfessorAviLoeb
https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd
https://x.com/ProfAviLoeb
