Fermi’s Paradox addresses the Drake equation, one way to get an estimate of the number of space-faring, technologically advanced civilizations in the Universe today. Source: UNIVERSITY OF ROCHESTER
Fermi’s Paradox is a great way to think about the possibility of life, in this case technologically advanced civilizations in the universe. Below is the text from an early draft of SOT that was deleted from the book. This is a conversation the crew had in space on the way to Thalassa and is an introduction to the Paradox.
As she stared out into black space an amazing star field unfolded before her. Although the Milky Way dominated the sky she could still make out the constellations she had known as a child. Seeing the familiar asterisms of Orion and the Bailer of Makali‘I she suddenly felt nostalgic, remembering memories of her father in the cold void of space.
Georgia reached over and touched Sage’s shoulder. “You ok? You look depressed.”
She came back to the present, realizing her eyes were wet with tears at the memories of her father. “I’m fine.” She smiled, realizing that Georgia had a warm side she hadn’t noticed before.
It had been three weeks since their initial team meeting and their first detailed discussion about Thalassa. They had arrived at K-Geo station, boarded a Cutten solar shuttle, which was full of other passengers heading to various destinations, and we’re just a few hours away from docking at Cassini station. She sat with Byron, Georgia, and Milo in a large communal dining space on the shuttle that looked back on Jupiter and its many moons which they had passed 12 days ago.
Sage had been staring at Procyon, thinking about her tutu’s vision and last words, when thoughts of her father took over. Milo walked in and Sage asked again about the Proteus mission and evidence of life on Thalassa, which prompted Byron to launch into a tirade about Fermi’s Paradox, which she had never heard of. Moshe was filming the discussion, to be used in a documentary about the mission.
“Enrico Fermi was a physicist, and a brilliant one at that,” Byron spoke with a passion and knowledge that showed he cared deeply about the subject and had an equally strong opinion. “The paradox arose from a conversation with other physicists where he simply asked the question, in the middle of lunch I might add, ‘Where is everybody?’”
Then Georgia interrupted, “In other words: if the galaxy is full of intelligent life why haven’t we seen or heard from them? Why aren’t they already on earth? I mean the universe is over 13.8 billion years old, they’ve had plenty of time!”
“Let me back up a bit so you can see the big picture,” interjected Byron. “There are three possibilities here. One, intelligent life doesn’t exist. Two, life exists but we haven’t communicated with them. And three, they are already on earth. I believe in the first explanation: we are alone in the universe.”
Moshe, who was listening while filming, agreed. “Yes, I believe that is true. We are God’s unique creations and the universe is here for us. Just us.”
Sage, as a biologist, was clearly getting worked up. “You guys are crazy. How can you say that given the billions and billions of stars, many of which have planets, some of which must have life? I agree it’s probably very rare but given all the possibilities there could still be tons of life out there.”
“But remember Sage,” Georgia added. “We’re not talking about life but intelligent life. About the possibility of civilizations advanced enough to travel through space or at least make noise that we can hear with our radio telescopes.”
Byron quickly interjected. “Yes, intelligent life but I don’t believe there is complex life, period. At least nothing beyond microbial life. Just think of all the terms in the Drake equation!”
“Come on Byron,” quipped Milo who had been passively listening. “Cut the math crap.
“Ok,” Byron replied. “It’s just that the earth and our solar system are more unique than most people know and life may have evolved here due to a very narrow range of possibilities.” Then Byron began to lecture on a topic he had clearly discussed before. “First, even though the universe is 13.8 billion years, our sun is only 4.6 billion years old and is about halfway through its life. In another 5 billion years, it will turn into a red giant and destroy the earth. So, it took almost half of the sun’s life for us to emerge. That’s cutting it close if you ask me. And many stars, like Procyon for example, have much shorter lives than our sun, some only tens to hundreds of millions of years or perhaps several billion.”
Georgia disagreed “Sure, that’s true but even on earth there was unicellular life after only 300 million years, so it is possible. Moreover, aren’t you forgetting red dwarfs, the most common type of star in the galaxy? They live for over a trillion years and so would their planets!”
“That’s true,” replied Byron. “But they are so dim their habitable zones are very close to the star and planets that close is bombarded by radiation and quickly become tidally locked to their suns so they generally bake on one side and freeze on the other. Not conducive to life.” He said with a smug look.
Since no one rebutted that statement he continued. “Perhaps even more importantly, rocky planets like ours are rare, as are rocky planets that live for a long period of time in the habitable zone. Moreover, having a large neighbor like Jupiter appears to be important as the huge mass sucks up most of the life-destroying collisions with asteroids and comets. Another factor is our moon, which is large relative to the size of the earth. It also takes collisions on our behalf and creates tides which were likely important for the evolution of life.”
Sage shook her head at the bombardment of complex ideas present in the debate.
Byron concluded. “Then add on top of that earth’s plate tectonics, which recycles gases and regulates climate, our magnetic field, which protects us and our atmosphere from solar radiation, etc. What you end up with is a combination of so many uncommon factors that it makes life almost impossible to evolve, let alone intelligent life, anywhere else. No, I think we are quite alone and unbelievably rare and precious.” Moshe nodded and showed a rare smile.
“Well,” said Sage, grinning at Byron. “That’s quite a lecture, and obviously well thought out, but maybe we just haven’t looked in the right places or communicated in the right way.”
Milo added. “It’s possible but SETI is over 100 years old and has never received a signal. That’s pretty compelling evidence.”
Then Sage added, somewhat jokingly. “Maybe they are just happy where they are and don’t want to waste time on the ‘interstellar net’ or whatever. Just because they aren’t exactly like us doesn’t mean they don’t exist. “
“I actually agree, Sage,” replied Milo. “But if intelligent life exists we’re probably talking about more than one civilization here, perhaps thousands. Clearly at least one of them would want to travel or send signals and we would have heard them by now. It is puzzling.”
“I guess I don’t feel that we’re alone in the universe,” said Sage. “I know it isn’t science but Hawaiians believe the gods, their ancestors, came from the stars and colonized the earth and left guardians to watch over us. The guardians were a bridge between the human and spiritual world. I’ve always looked at the stars and felt their presence. Our ancestors are out there, I know they are. They just have to be. So we can’t be alone.”
Byron was agitated “You’re right, that’s not science. It’s religion and faith and not based on evidence. Believe what you want but only science is truth.”
“No, it’s based on believing in something bigger than yourself,” said Moshe, coming to Sage’s defense. “Lack of physical evidence does not mean it doesn’t exist.”
Despite Moshe’s support, Sage was taken aback by Byron’s comment. Although she knew her comment was unscientific she didn’t like it thrown back in her face. Although she could feel her childhood faith in the Hawaiian gods waning, her tutu’s and father’s teachings had lodged the idea deeply in her psyche. More importantly, the recent string of events involving Procyon just seemed too coincidental to lack meaning. The star and her name and tutu’s funeral. Maybe it really was her destiny to travel to Procyon. Well, she was on her way and would just have to figure it out. She just had to have faith that she was doing the right thing. Although she agreed that science was likely the larger truth, the idea that she was heading towards the home of her ancestral gods helped her accept her mission more easily.
Georgia interrupted her thoughts. “I’m not sure about all that but we must also consider the vastness of space and the barrier that represents. We are all so isolated. Ok, so here’s one way to think about space. Everyone knows what an AU is, right?” But she saw the confused look on Sage’s face. “An AU, or Astronomical Unit” is a standard measure of distance in space. It’s the distance from the earth to the sun, about 93 million miles. We’ve been traveling for three weeks and we are getting close to Saturn, which is about 9.5 AU from the sun. Imagine extending that out a bit further, to the next planet, Uranus, which at 19 AU, is still quite a ways from the sun. So, for scale take the size of our solar system out to Uranus as the size of a quarter. Based on this model our nearest star, Proxima Centauri, is a football field away from that quarter, about 4.2 light-years or 15,000 AU. That’s the closest star! Where we are going, Procyon is 11.46 light-years from us, or almost 3 football fields away from our quarter, our solar system, or 41,000 AU, about 4 trillion miles. Backing up some more, our galaxy alone is 100,00 light-years across! The universe itself is much bigger, likely 46 billion light-years across, so it’s big and incredibly spread out so it’s a huge barrier to interstellar travel. So even if there is advanced life we may never see it.” Georgia stopped, looking satisfied to have made her point.
Milo was listening intensely but spoke up at the mention of Procyon. “But you’re forgetting the worm portals, aren’t you? With the portal, it doesn’t matter how far apart things are although we are limited by mass and energy costs.”
“That’s true,” replied Georgia. “But it was pure luck that we discovered it. We would never have discovered the secrets to exotic matter without the supercollider explosion during the Higgs boson experiment. Without that accident, we’d be spending most of our lives traveling to and from close stars in cryo-sleep.”
But then she continued “Byron has made the point that life, particularly intelligent life, is probably non-existent due to the amazing string of events that must happen to develop the right conditions. I don’t entirely disagree. But I also believe that life is a force in itself. And just as physics and chemistry drive the physical evolution of the universe, biology drives the evolution of life. And if we’ve learned anything it’s that life begets itself. Life is resilient and will find a way. Somehow, life will find a way. As the great Stephan Hawkins once said, ‘when there is life, there is hope.’”
Kami [Sage’s brother, deleted from the book], who had been standing nearby unnoticed listening to the conservation, spoke up. “I think they’re already here, you know like Chariots of the Gods and UFOs.” At which point everyone laughed, including Kaimi. “But my favorite idea” he added “Is that they are watching us, and we are living in their zoo, like those old movies ‘The Matrix’ or the ‘The Truman Show’.” Or maybe they even have a prime directive like on Star Trek: do not interfere with intelligent life!” Again, everyone laughed but it caused Sage to think about the old Hawaiian myths and origins of the gods, and the time with her father.
An announcement interrupted their conversation: the shuttle was approaching Cassini station and it was time to prepare for docking. Milo quickly yelled over the rising noise levels “Anyhow, we’re about to find out for ourselves!” as everyone ran to their cabins to grab their personal gear and move to the off-loading dock.
As Sage reached her cabin to grab her stuff, she felt fear in her stomach. This was it, she thought, I’m leaving home, the solar system, and heading out into the unknown.
Further reading:
- Webb, Stephen. 2002. If the Universe Is Teeming with Aliens … Where is Everybody? Fifty Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life. Springer Science & Business Media, 288 pp.
- The Fermi Paradox, Waitbutwhy.com
Songs of Thalassa 