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Why We Should Really Stop Trying to Contact Aliens
The Three-Body Problem series lays out a powerful case for why we should stop looking for aliens, and solves the Fermi paradox.
Experts are more and more convinced there’s probably intelligent life out there. Our first impulse, being friendly Earth types, is to reach out and say hi — from 1977’s Voyager to SETI@home, we can’t wait to meet the neighbors. Some scientists, like Stephen Hawking, caution that this may be a lethal mistake, and others say, “Naw, not to worry.” Yet here we are, scanning the night skies, visions of Close Encounters in our heads. A recent work of science fiction, though, contains a stunningly convincing argument that we should shut. The. Hell. Up. Hiding wouldn’t be a bad idea, either. The Fermi paradox, its author asserts, suggests that everyone else already is.
The book is The Dark Forest, the second volume in the unforgettable Three-Body trilogy by Chinese writer Cixin Liu. Cixin’s writing is beyond smart — it’s brilliant — and it's science fiction of the best kind, with mind-boggling ideas and perceptions, and characters you care about. His concept of the dark forest, though presented in a work of fiction, is chilling, and very real.
The Axioms of Social Cosmology
In The Dark Forest, a character suggests the creation of an area of study called “cosmic sociology.” She describes it as a means of understanding the interactions of distant civilizations who know each other only as dots of light, light years away. It's based on two simple, inarguable axioms that would be true of every civilization, regardless of the life forms it contains or where it is in the universe:
To complete the picture, the character says, one needs to understand two other important concepts:
Chains of Suspicion
When one civilization becomes aware of another, the most critical thing is to ascertain whether or not the newly found civilization is operating from benevolence — and thus won’t attack and destroy you — or malice. Too much further communication could take you from limited exposure in which the other civilization simply knows you exist, to the strongest: They know where to find you. And so each civilization is left to guess the other’s intent, and the stakes couldn't be higher.
You can’t assume the other civilization is benevolent, and they can't assume that about you, either. Nor can you be sure the other correctly comprehends your assessment of their benevolence or maliciousness. As one character tells another in the book:
Next, even if you know that I think you’re benevolent, and I also know that you think I’m benevolent, I don’t know what you think about what I think about what you’re thinking about me. It's convoluted, isn't it?
Does the other civilization see your opinion of them as a reason to relax, or to conquer you and take your resources? How can you possibly know what to make of each other with a certainty that satisfies your desire for survival? Inevitably, neither civilization can afford to trust the other, There’s just no way to discern another’s true intention from so very far away.
You do know that a civilization that contacts you is capable technologically of at least that much. But this is all you have to go on in your assessment of the threat level or their ability to defend themselves against an attack from you. You might think that a civilization that considers itself advanced could relax, secure in its military superiority at the moment of first contact. But contact with you could be just the impetus needed for the other civilization to shoot ahead technologically — progress is non-linear, as shown by our own tech explosion in just 300 years against the millions of years we’ve been around. By the time an invading force traverses the vast expanse of space — likely over the course of years, if not centuries — who can know what awaits them? No civilization can be confident of its power relative to the other.
The person listening to this in The Dark Forest responds, “So I have to keep quiet.” After a pause, he asks, “Do you think that will work?”
Nope. “To sum up,” says the first speaker, “letting you know I exist, and letting you to continue to exist, are both dangerous to me and violate the first axiom.” So, he continues, “If neither communication nor silence will work once you learn of my existence, you’re left with just one option.” Attack.
As if what’s already been argued isn’t scary enough, he reminds his listener, “Extrapolate that option out to billions and billions of stars and hundred of millions of civilization’s and there’s your picture. The real universe is just that black.”
Welcome to the Woods
Cixin’s dark forest metaphor goes like this:
The universe is a dark forest. Every civilization is an armed hunter stalking through the trees like a ghost, gently pushing aside branches that block the path and trying to tread without sound. Even breathing is done with care. The hunter has to be careful, because everywhere in the forest are stealthy hunters like him. If he finds another life — another hunter, angel, or a demon, a delicate infant to tottering old man, a fairy or demigod — there’s only one thing he can do: open fire and eliminate them.
And here’s us with our desire for contact:
But in this dark forest, there’s a stupid child called humanity, who has built a bonfire and is standing before it shouting, “Here I am! Here I am!”
So the answer to the Fermi paradox may simply be this: Civilizations aware of the dark forest concept are wisely hiding.
In The Three-Body Problem, the first book in the series, a scientist sends out a message and years later receives the following cautionary response:
Do not answer!
Do not answer!!
Do not answer!!!
I am a pacifist in this world. It is the luck of your civilization that I am the first to receive your message. I am warning you: Do not answer! Do not answer!! Do not answer!!!
There are tens of millions of stars in your direction. As long as you do not answer, this world will not be able to ascertain the source of your transmission.
But if you do answer, the source will be located right away. Your planet will be invaded. Your world will be conquered.
Do not answer! Do not answer!! Do not answer!!!
We won't spoil the story by revealing what the scientist does. And we can't recommend the Three-Body Problem series highly enough.
Geologists discover a rhythm to major geologic events.
- It appears that Earth has a geologic "pulse," with clusters of major events occurring every 27.5 million years.
- Working with the most accurate dating methods available, the authors of the study constructed a new history of the last 260 million years.
- Exactly why these cycles occur remains unknown, but there are some interesting theories.
Our hearts beat at a resting rate of 60 to 100 beats per minute. Lots of other things pulse, too. The colors we see and the pitches we hear, for example, are due to the different wave frequencies ("pulses") of light and sound waves.
Now, a study in the journal Geoscience Frontiers finds that Earth itself has a pulse, with one "beat" every 27.5 million years. That's the rate at which major geological events have been occurring as far back as geologists can tell.
A planetary calendar has 10 dates in red
Credit: Jagoush / Adobe Stock
According to lead author and geologist Michael Rampino of New York University's Department of Biology, "Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geologic events are correlated and not random."
The new study is not the first time that there's been a suggestion of a planetary geologic cycle, but it's only with recent refinements in radioisotopic dating techniques that there's evidence supporting the theory. The authors of the study collected the latest, best dating for 89 known geologic events over the last 260 million years:
- 29 sea level fluctuations
- 12 marine extinctions
- 9 land-based extinctions
- 10 periods of low ocean oxygenation
- 13 gigantic flood basalt volcanic eruptions
- 8 changes in the rate of seafloor spread
- 8 times there were global pulsations in interplate magmatism
The dates provided the scientists a new timetable of Earth's geologic history.
Tick, tick, boom
Credit: New York University
Putting all the events together, the scientists performed a series of statistical analyses that revealed that events tend to cluster around 10 different dates, with peak activity occurring every 27.5 million years. Between the ten busy periods, the number of events dropped sharply, approaching zero.
Perhaps the most fascinating question that remains unanswered for now is exactly why this is happening. The authors of the study suggest two possibilities:
"The correlations and cyclicity seen in the geologic episodes may be entirely a function of global internal Earth dynamics affecting global tectonics and climate, but similar cycles in the Earth's orbit in the Solar System and in the Galaxy might be pacing these events. Whatever the origins of these cyclical episodes, their occurrences support the case for a largely periodic, coordinated, and intermittently catastrophic geologic record, which is quite different from the views held by most geologists."
Assuming the researchers' calculations are at least roughly correct — the authors note that different statistical formulas may result in further refinement of their conclusions — there's no need to worry that we're about to be thumped by another planetary heartbeat. The last occurred some seven million years ago, meaning the next won't happen for about another 20 million years.
Brain cells snap strands of DNA in many more places and cell types than researchers previously thought.
The urgency to remember a dangerous experience requires the brain to make a series of potentially dangerous moves: Neurons and other brain cells snap open their DNA in numerous locations — more than previously realized, according to a new study — to provide quick access to genetic instructions for the mechanisms of memory storage.
The extent of these DNA double-strand breaks (DSBs) in multiple key brain regions is surprising and concerning, says study senior author Li-Huei Tsai, Picower Professor of Neuroscience at MIT and director of The Picower Institute for Learning and Memory, because while the breaks are routinely repaired, that process may become more flawed and fragile with age. Tsai's lab has shown that lingering DSBs are associated with neurodegeneration and cognitive decline and that repair mechanisms can falter.
"We wanted to understand exactly how widespread and extensive this natural activity is in the brain upon memory formation because that can give us insight into how genomic instability could undermine brain health down the road," says Tsai, who is also a professor in the Department of Brain and Cognitive Sciences and a leader of MIT's Aging Brain Initiative. "Clearly, memory formation is an urgent priority for healthy brain function, but these new results showing that several types of brain cells break their DNA in so many places to quickly express genes is still striking."
In 2015, Tsai's lab provided the first demonstration that neuronal activity caused DSBs and that they induced rapid gene expression. But those findings, mostly made in lab preparations of neurons, did not capture the full extent of the activity in the context of memory formation in a behaving animal, and did not investigate what happened in cells other than neurons.
In the new study published July 1 in PLOS ONE, lead author and former graduate student Ryan Stott and co-author and former research technician Oleg Kritsky sought to investigate the full landscape of DSB activity in learning and memory. To do so, they gave mice little electrical zaps to the feet when they entered a box, to condition a fear memory of that context. They then used several methods to assess DSBs and gene expression in the brains of the mice over the next half-hour, particularly among a variety of cell types in the prefrontal cortex and hippocampus, two regions essential for the formation and storage of conditioned fear memories. They also made measurements in the brains of mice that did not experience the foot shock to establish a baseline of activity for comparison.
The creation of a fear memory doubled the number of DSBs among neurons in the hippocampus and the prefrontal cortex, affecting more than 300 genes in each region. Among 206 affected genes common to both regions, the researchers then looked at what those genes do. Many were associated with the function of the connections neurons make with each other, called synapses. This makes sense because learning arises when neurons change their connections (a phenomenon called "synaptic plasticity") and memories are formed when groups of neurons connect together into ensembles called engrams.
"Many genes essential for neuronal function and memory formation, and significantly more of them than expected based on previous observations in cultured neurons … are potentially hotspots of DSB formation," the authors wrote in the study.
In another analysis, the researchers confirmed through measurements of RNA that the increase in DSBs indeed correlated closely with increased transcription and expression of affected genes, including ones affecting synapse function, as quickly as 10-30 minutes after the foot shock exposure.
"Overall, we find transcriptional changes are more strongly associated with [DSBs] in the brain than anticipated," they wrote. "Previously we observed 20 gene-associated [DSB] loci following stimulation of cultured neurons, while in the hippocampus and prefrontal cortex we see more than 100-150 gene associated [DSB] loci that are transcriptionally induced."
Snapping with stress
In the analysis of gene expression, the neuroscientists looked at not only neurons but also non-neuronal brain cells, or glia, and found that they also showed changes in expression of hundreds of genes after fear conditioning. Glia called astrocytes are known to be involved in fear learning, for instance, and they showed significant DSB and gene expression changes after fear conditioning.
Among the most important functions of genes associated with fear conditioning-related DSBs in glia was the response to hormones. The researchers therefore looked to see which hormones might be particularly involved and discovered that it was glutocortocoids, which are secreted in response to stress. Sure enough, the study data showed that in glia, many of the DSBs that occurred following fear conditioning occurred at genomic sites related to glutocortocoid receptors. Further tests revealed that directly stimulating those hormone receptors could trigger the same DSBs that fear conditioning did and that blocking the receptors could prevent transcription of key genes after fear conditioning.
Tsai says the finding that glia are so deeply involved in establishing memories from fear conditioning is an important surprise of the new study.
"The ability of glia to mount a robust transcriptional response to glutocorticoids suggest that glia may have a much larger role to play in the response to stress and its impact on the brain during learning than previously appreciated," she and her co-authors wrote.
Damage and danger?
More research will have to be done to prove that the DSBs required for forming and storing fear memories are a threat to later brain health, but the new study only adds to evidence that it may be the case, the authors say.
"Overall we have identified sites of DSBs at genes important for neuronal and glial functions, suggesting that impaired DNA repair of these recurrent DNA breaks which are generated as part of brain activity could result in genomic instability that contribute to aging and disease in the brain," they wrote.
The National Institutes of Health, The Glenn Foundation for Medical Research, and the JPB Foundation provided funding for the research.
Research shows that those who spend more time speaking tend to emerge as the leaders of groups, regardless of their intelligence.
- A new study proposes the "babble hypothesis" of becoming a group leader.
- Researchers show that intelligence is not the most important factor in leadership.
- Those who talk the most tend to emerge as group leaders.
If you want to become a leader, start yammering. It doesn't even necessarily matter what you say. New research shows that groups without a leader can find one if somebody starts talking a lot.
This phenomenon, described by the "babble hypothesis" of leadership, depends neither on group member intelligence nor personality. Leaders emerge based on the quantity of speaking, not quality.
Researcher Neil G. MacLaren, lead author of the study published in The Leadership Quarterly, believes his team's work may improve how groups are organized and how individuals within them are trained and evaluated.
"It turns out that early attempts to assess leadership quality were found to be highly confounded with a simple quantity: the amount of time that group members spoke during a discussion," shared MacLaren, who is a research fellow at Binghamton University.
While we tend to think of leaders as people who share important ideas, leadership may boil down to whoever "babbles" the most. Understanding the connection between how much people speak and how they become perceived as leaders is key to growing our knowledge of group dynamics.
The power of babble
The research involved 256 college students, divided into 33 groups of four to ten people each. They were asked to collaborate on either a military computer simulation game (BCT Commander) or a business-oriented game (CleanStart). The players had ten minutes to plan how they would carry out a task and 60 minutes to accomplish it as a group. One person in the group was randomly designated as the "operator," whose job was to control the user interface of the game.
To determine who became the leader of each group, the researchers asked the participants both before and after the game to nominate one to five people for this distinction. The scientists found that those who talked more were also more likely to be nominated. This remained true after controlling for a number of variables, such as previous knowledge of the game, various personality traits, or intelligence.
How leaders influence people to believe | Michael Dowling | Big Think www.youtube.com
In an interview with PsyPost, MacLaren shared that "the evidence does seem consistent that people who speak more are more likely to be viewed as leaders."
Another find was that gender bias seemed to have a strong effect on who was considered a leader. "In our data, men receive on average an extra vote just for being a man," explained MacLaren. "The effect is more extreme for the individual with the most votes."
The great theoretical physicist Steven Weinberg passed away on July 23. This is our tribute.