I sometimes wonder what the first thing an extraterrestrial civilization would want to tell us in their interstellar transmission.
I doubt the greeting would be “live long as prosper”; the mantra of Star Trek’s Mr. Spock.
What do aliens think we’d be interested in hearing about? It may be something as abstruse as: “show me your equation of state and I’ll show you mine.”
The equation of state is the measure of the stability of dark energy. Discovered in 1996 and predicted decades earlier by Albert Einstein, this repulsive form of gravity appears to spread uniformly throughout space. If dark energy is unstable, it could eventually tear apart the universe or cause it to implode.
Dark energy packs a repulsive “push” into every cubic yard of space. Gravity and radiation dilute as the universe expands. But current measurement suggest that dark energy remains a constant force.
Why would extraterrestrials think we’d be interested in their value for dark energy?
For one simply reason: Inquiring minds across the galaxy must be asking: “why me, why now?”
This quote isn’t from Mr. Spock, but from champion figure skater Nancy Kerrigan who uttered the phrase in 1994 after being attacked and injured by an opponent.
Like us, alien scientists are realizing that we just happen to be living at a singularly unique nexus in the universe’s history.
When Earth first formed, a 7 billion year-old arm wrestle between gravity and dark energy ended. Dark energy overcame gravity because gravity becomes increasingly rarefied the bigger the universe gets. Dark energy has been propelling the universe apart ever faster since then.
Now, the spooky part is that this game-changer coincidentally happened at the same time intelligent life should have blossomed across our Milky Way galaxy, says a pair of Australian theoreticians, Charles Lineweaver and Chas Egan.
Five billion years ago the galaxy was polluted with enough heaver elements — such as carbon, oxygen and silicon — from the first-generation stars, to start building terrestrial planets. In fact, most of the planets the universe will ever contain had already been made. That’s because the universe went though a baby boom of star making — you guessed it — 5 billion years ago, when the sun and solar system formed.
Around that same time a biological phase transition happened too. Inanimate matter transitioned to becoming self-replicating matter that undergoes Darwinian evolution. If life is a condition of the universe, this phenomenon must have swept across the galaxy in the past few billion years. Over that same period a subset of planets should have nurtured the evolution of complex life.
Today, alien astronomers across the galaxy have come of age in parallel with us, say the researchers. Those extraterrestrials a similar inquisitiveness as ours, and who are technologically empowered, are also discovering that the universe is accelerating.
E.T.’s own brand of physics is coming to grips with the reality of this overwhelming force, which accounts for 73 percent of the matter-energy budget of the universe. Like us they too must be pondering what it means for the universe’s ultimate fate.
There’s plenty of wiggle room in this timetable for the evolution of civilizations that are a few million years ahead of us. They may have already solved the dark energy mystery. But like school kids, they may want to check their homework against some else’s.
My guess is that the really smart extraterrestrials who have figured this out are scattered far away in space and time, so I doubt any alien transmission is going to give us the ultimate solution to dark energy any time soon. But it is a truly universal question that unites sentient beings whose minds evolved under different alien suns.
What is unsettling to me is that this whole idea is anti-Copernican. Coperincanism states that there is nothing unique about the observer’s location in space or time. But on the face of it we live in a very special time.
The only way out of this conundrum is to assume that all times are special in the evolving universe. Whatever self-aware entities might exist a trillion years from now will have their own unique cosmological mysteries.
Nevertheless, is the emergence of intelligence and the onset of an accelerating universe purely coincidental? Or, are their deeper truths we have yet to realize?
Image credits: NASA, ESO