- 12 hours ago
Why Habitable Exoplanets Might Mean Humanity Is Doomed:
Last week, scientists announced the discovery of Kepler 186f, a planet 492 light years away in the Cygnus constellation. Kepler 186f is special because it marks the first planet almost exactly the same size as Earth orbiting in the “habitable zone” – the distance from a star in which we might expect liquid water, and perhaps life.
What did not make the news, however, is that this discovery also slightly increases how much credence we give to the possibility of near-term human extinction. This because of a concept known as the Great Filter.
The Great Filter is an argument that attempts to resolve the Fermi Paradox: why have we not found aliens, despite the existence of hundreds of billions of solar systems in our galactic neighborhood in which life might evolve? As the namesake physicist Enrico Fermi noted, it seems rather extraordinary that not a single extraterrestrial signal or engineering project has been detected (UFO conspiracy theorists notwithstanding).
This apparent absence of thriving extraterrestrial civilizations suggests that at least one of the steps from humble planet to interstellar civilization is exceedingly unlikely. The absence could be caused because either intelligent life is extremely rare or intelligent life has a tendency to go extinct. This bottleneck for the emergence of alien civilizations from any one of the many billions of planets is referred to as the Great Filter.
Are we alone?
What exactly is causing this bottleneck has been the subject of debate for more than 50 years. Explanations could include a paucity of Earth-like planets or self-replicating molecules. Other possibilities could be an improbable jump from simple prokaryotic life (cells without specialized parts) to more complex eukaryotic life – after all, this transition took well over a billion years on Earth.
Proponents of this “Rare Earth” hypothesis also argue that the evolution of complex life requires an exceedingly large number of perfect conditions. In addition to Earth being in the habitable zone of the sun, our star must be far enough away from the galactic center to avoid destructive radiation, our gas giants must be massive enough to sweep asteroids from Earth’s trajectory, and our unusually large moon stabilizes the axial tilt that gives us different seasons.
These are just a few prerequisites for complex life. The emergence of symbolic language, tools and intelligence could require other such “perfect conditions” as well.
Or is the filter ahead of us?
While emergence of intelligent life could be rare, the silence could also be the result of intelligent life emerging frequently but subsequently failing to survive for long. Might every sufficiently advanced civilization stumble across a suicidal technology or unsustainable trajectory? We know that a Great Filter prevents the emergence of prosperous interstellar civilizations, but we don’t know whether or not it lies in humanity’s past or awaits us in the future.
For 200,000 years humanity has survived supervolcanoes, asteroid impacts, and naturally occurring pandemics. But our track record of survival is limited to just a few decades in the presence of nuclear weaponry. And we have no track record at all of surviving many of the radically novel technologies that are likely to arrive this century.
Esteemed scientists such as Astronomer Royal Martin Rees at the Cambridge Centre for the Study of Existential Risk point to advances in biotechnology as being potentially catastrophic. Others such as Stephen Hawking, Max Tegmark and Stuart Russell, also with the Cambridge Centre, have expressed serious concern about the exotic but understudied possibility of machine superintelligence.
Let’s hope Kepler 186f is barren
When the Fermi Paradox was initially proposed, it was thought that planets themselves were rare. Since then, however, the tools of astronomy have revealed the existence of hundreds of exoplanets. That just seems to be the tip of the iceberg.
But with each new discovery of an Earth-like planet in the habitable zone, such as Kepler 186f, makes it less plausible that there are simply no planets aside from Earth that might support life. The Great Filter is thus more likely to be lurking in the path between habitable planet and flourishing civilization.
If Kepler 186f is teeming with intelligent life, then that would be really bad news for humanity. For that fact would push back the Great Filter’s position further into the technological stages of a civilizations development. We might then expect that catastrophe awaits both our extraterrestrial companions and ourselves.
In the case of Kepler 186f, we still have many reasons to think intelligent life might not emerge. The atmosphere might be too thin to prevent freezing, or the planet might be tidally locked, causing a relatively static environment. Discovery of these hostile conditions should be cause for celebration. As philosopher Nick Bostrom once said:
The silence of the night sky is golden … in the search for extraterrestrial life, no news is good news. It promises a potentially great future for humanity.
Curious #et #life #aliensSource: Mashable
- 12 hours ago
- 12 hours ago
Why Physicists Are Saying Consciousness Is A State Of Matter, Like a Solid, A Liquid Or A Gas
A new way of thinking about consciousness is sweeping through science like wildfire. Now physicists are using it to formulate the problem of consciousness in concrete mathematical terms for the first time
There’s a quiet revolution underway in theoretical physics. For as long as the discipline has existed, physicists have been reluctant to discuss consciousness, considering it a topic for quacks and charlatans. Indeed, the mere mention of the ‘c’ word could ruin careers.
That’s finally beginning to change thanks to a fundamentally new way of thinking about consciousness that is spreading like wildfire through the theoretical physics community. And while the problem of consciousness is far from being solved, it is finally being formulated mathematically as a set of problems that researchers can understand, explore and discuss.
Well. Consciousness huh? It’s getting a bit airy fairy.
(via abcstarstuff)Source: medium.com
- 5 days ago
If you thought the post on twins sharing consciousness was awesome, wait until you hear this.
A 44-year-old French man one day went to the trip to the doctor’s because he felt a pain in his left leg. He’s a married man with two kids and a steady job.
Doctor’s found that he had hydrocephalus as a child (when your brain is filled with fluids) so they decided to run some brain scans.
What they found was that the majority of his head was filled with fluid. Over time, the buildup caused his lateral ventricles to swell so much that his brain had been flattened to a thin sheet.
Doctors estimated that his brain mass had been reduced by at most 70%, affecting the areas in charge of motion, language, emotion, and, well, everything.
Shockingly, he was fine. While his IQ was only 75, he wasn’t mentally challenged. He held a steady job, raised a family, and didn’t have trouble interacting with others.
Over time, his brain had adapted to all that pressure, and even though he had fewer neurons that most, Jacques was still a fully functional human being.
The doctors drained the fluid and while his brain is much smaller now, he is still a healthy individual with a normal life.
(via scienceyoucanlove)Source: sixpenceee
- 2 weeks ago
"If you’re poor, the only way you’re likely to injure someone is the old traditional way: artisanal violence, we could call it – by hands, by knife, by club, or maybe modern hands-on violence, by gun or by car. But if you’re tremendously wealthy, you can practice industrial-scale violence without any manual labor on your own part. You can, say, build a sweatshop factory that will collapse in Bangladesh and kill more people than any hands-on mass murderer ever did, or you can calculate risk and benefit about putting poisons or unsafe machines into the world, as manufacturers do every day. If you’re the leader of a country, you can declare war and kill by the hundreds of thousands or millions. And the nuclear superpowers – the US and Russia – still hold the option of destroying quite a lot of life on Earth."
- 2 weeks ago
- 3 weeks ago
Waterbears can go without food or water for more than a decade. They can survive temperatures from zero to above the boiling point of water, pressure six times stronger than the deepest ocean trench, radiation hundreds of times higher than the fatal dose for a human, and the vacuum of space.
(via abcstarstuff)Source: 4gifs
- 3 weeks ago
Australia’s largest land predator, introduced to the continent 3,000 to 5,000 years ago, is not a kind of wild dog, study finds
- from The Guardian“Australia's dingo is a unique species, not a kind of wild dog as previously believed, according to a new study that definitively classifies the country's largest land predator. The research by Australian scientists, published in the Journal of Zoology, resurrected the species name Canis dingo, first adopted in 1793 by Friedrich Meyer, a German naturalist.
"What we’ve done is describe the dingo more scientifically," Mike Letnic of the University of New South Wales told Reuters. The confusion over whether the dingo was a distinct species partly originated from the previous classification, which was based on a simple drawing and description in the 18th century journal of Australia’s first governor, Arthur Phillip, without reference to a physical specimen. "When Phillip got home to England he wrote about his adventures and in that book he wrote one paragraph about the dingo and published a picture and that was, until now, what science knew of the dingo,” Letnic said.
The team found the physical features that define the dingo are a slim build, relatively broad head, long snout, pointy ears and bushy tail, with a weight of 15 to 20kg (33 to 44lbs). To isolate dingoes unlikely to have cross-bred with domestic dogs, the team tracked 69 skull and skin specimens pre-dating 1900 in museums and archaeological sites in Europe, Australia and America to create a benchmark description.
"What we did was say this is what dingoes look like before 1900 and that’s what a dingo looks like because there were not very many dogs around," Letnic said. "That’s where the benchmark comes in." Dingoes were introduced to Australia around 3,000 to 5,000 years ago, with genetic evidence suggesting they originated from East Asian domestic dogs. They bred in isolation until the arrival of dogs accompanying European settlers from 1788" (read more).
***Cue thejunglenook for verification
- 3 weeks ago
Song from π!
Putting the “pi” in “piano”
Check out this awesome piano melody created from the digits of pi! By transposing the numbers 0-9 onto an A minor scale, the irrational melody is played with the right hand and notes are added with the left. It’s pretty mathemagical.
Also, try singing this along with the melody, either out loud or in your head (it totally works):
"I am listening to a sonnnnng about piiiiiii, maaaaking a melody as the numbers fly byyyyy"
Bonus: Check out Daniel Starr-Tambor’s “Mandala”, a melody created from the orbits of the planets placed onto a musical scale. At 62 viginitillion notes (I didn’t even know that was a number), it’s the longest palindrome ever created.
A song from pi. Brilliant!Source: jtotheizzoe