Friday, June 27, 2014

Intelligent life is just getting started | Praxtime

Intelligent life is just getting started | Praxtime

Intelligent life is just getting started

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I wrote an earlier post supporting the view that Earth is a unique planet. It's likely the only planet in our galaxy supporting complex life. I wanted to do an update after coming across an excellent post by Stephen Ashworth, who categorizes views on alien life into either "steady state" or "expansionist".

Ashworth starts by noting that early attempts to estimate the amount of intelligent life in the galaxy were based on steady state models. His illustration is below:

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In the steady state model, once the universe gets started the number of civilizations quickly plateaus. This is depicted as time "A" above. The steady state comes from assuming civilizations are born and die at a constant rate, and so over time the number stabilizes. This is the basis of the 1961 Drake Equation and also the model behind a lot of discussion of the Fermi Paradox. I love all the work and thought that went into this, but this approach is showing its 1960 roots. We should respectfully trash it.

Contrast this with what Ashworth characterizes as an expansionist model:

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In this model, life is an invasive species. Once it reaches a point where it can cross star systems, it rapaciously expands to fill the galaxy. Now we're talking. Darwinian life filling empty ecosystems to capacity. A nuance here is the expansionist model doesn't require every civilization to be expansionist, though Darwinian logic makes this plausible. The real key is the very first expansionist civilization that comes along fills the galaxy. Game over. So why did Drake even consider the steady state model back in 1960? Well, back then it was not clear you could build a starship. And even if you could, how would people survive centuries of travel through radiation filled space? With the constraint that civilizations were restricted to their home sun, the steady state model made sense. Alien civilizations were born alone, trapped around their sun, and eventually died alone.

It was not until the invention of computers and robotics that sending self-replicating probes became conceivable. Now you have a technology that can survive in space for the centuries, replicating to fill the galaxy. Once you accept interstellar travel is possible, and understand robotics, the expansionist view becomes impossible to avoid. Likewise the steady state model becomes archaic and ridiculous, given it's foundational premise is interstellar travel is impossible. Here's a quote from Frank Tipler's paper from 1981:

The basic idea of my argument is straightforward and indeed has led other authors such as Fermi (10), Dyson (11), Hart (12), Simpson(6), and Kuper & Morris (13), to conclude that extraterrestrial intelligent beings do not exist: if they did exist and possessed the technology for interstellar communication they would also have developed interstellar travel and thus would be present in our solar system. Since they are not here (14,15), it follows that they do not exist. Although this argument has been expressed before, its force does not seem to have been appreciated.

Exactly. It's force was not appreciated in 1981. And is still not completely appreciated now, over 30 years later. The search for extraterrestrial life (SETI) muddles along stuck in the 1960's, unable to get out. People are still publishing brand new books based on the Fermi paradox and the Drake equation. Please make it stop.

Of course the main reason the public believes simultaneously in interstellar travel and aliens is it makes for awesome popcorn movies. Well enough. I love good alien movies too. But even people who are aware of the argument above can struggle. I think the reason is the relative timescales involved. Let's start with the age of the universe. It's 13.8 billion years old as depicted below.

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Our Sun and the Earth formed about 4.5 billion years ago. Microbial life evolved shortly after. Intelligent life evolved 3 billion years after the start of life. Repeat: billions of years to evolve intelligent life. In fact, life will end on Earth due to the expanding Sun in only another two billion years. So in some sense we barely evolved in time.

Now compare the billions of years for intelligent life to evolve to the time it takes to expand into the galaxy with self replicating probes. That's only 20 million years. In the picture above on the far right is a green vertical line showing 20 million years. You may have to squint to find it. It's an eyeblink.

Now step out even further in time. It turns out the universe will produce stars into the future for 100's of billions of years. A typical figure is 10's of trillions. Let's just use 1 trillion for the scale below. On the far left in red is the 13 billion year age of the universe, which on the new scale looks pretty short. Each block is 100 billion years wide. We still have stars forming at 1 trillion years, and beyond. It's still daybreak from the universe's point of view.

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We have three disparate time scales: millions, billions and trillions. For simplicity let's round the numbers to 20, 20, 20:

  1. Time for intelligent life to fill galaxy: super short 20 million years
  2. Time for intelligent life to evolve: moderate 20 billion years
  3. Time of universe to keep having stars: long 20 trillion years

The first timescale is the expansionist view of populating the galaxy. It's easy to reject emotionally but hard to reject logically. That's because the expansionist view merely assumes interstellar travel is possible and Darwinian evolved life fills ecosystems. Some math here. The second number is based on the observation that aliens haven't flooded the galaxy yet. Plus supporting data that intelligent life evolved very late in Earth's history after billions of years. The last number is current astrophysics and seems very solid. Overall we have a spare, powerful and persuasive model for why there are no aliens. Life has barely had time to get started.

Unfortunately this model shows the chances of us meeting a second form of intelligent life are nil. It takes billions of years to evolve, and millions of years to flood the galaxy. First one gets it all. Also note there's plenty more time for intelligent life to evolve elsewhere before the universe gets old. So if humans self-destruct before expanding, then other intelligent aliens will do it later. In say, another 10 billion years.



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Avoiding “Sagan Syndrome.” Why Astronomers and Journalists should pay heed to Biologists about ET. | Praxtime

http://praxtime.com/2013/11/25/sagan-syndrome-pay-heed-to-biologists-about-et/


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Monday, June 23, 2014

Eric's Archived Thoughts: The Truth

Eric's Archived Thoughts: The Truth: "
She pointed at Kat.  Shifted her head up and around.  Whispered, her voice so tiny and full of pain and fear and breaking into another wail:  “Of dying.”

I will never know how long we wept with her.  What we said to try to soothe her pain even a tiny bit.  How we tried to comfort and protect her.  I will always remember how utterly helpless and wounded and shattered I felt, the sick ache in the center of my chest.

Eventually the tears came to an end, as all things must.  She hadn’t moved from her place, curled up against Kat, still holding one of my hands.  Her face was clouded and stormy with the echoes of her tears, but there was some measure of calm.  It let Kat and me come to the same place, quiet and still in the shadow of all our grief.  We asked if she had any questions; she shook her head.  We told her we loved her.  She whispered, almost but not quite crying again, “I love you too.”  We kissed her, almost but not quite crying again.

"



'via Blog this'

Wednesday, June 11, 2014

I’m Just Now Realizing How Stupid We Are

I'm Just Now Realizing How Stupid We Are

I'm Just Now Realizing How Stupid We Are

This is my 3,000th column. I've learned a tremendous amount in writing about investing and the economy. Here are a few of the big lessons. 

I've learned that changing your mind is one of the most difficult things we do. It is far easier to fool yourself into believing a falsehood than admit a mistake.

I've learned that people are terrible at predicting their own emotions. You will be more fearful when the market is crashing and more greedy when it is surging than you think. 

I've learned that strong political beliefs in either direction limit your ability to make rational decisions more than almost anything else.

I've learned that short-term thinking is at the root of most of our problems, whether it's in business, politics, investing, or work.

I've learned that debt can cause more social problems than some drugs, yet drugs are illegal and debt is tax deductible.

I've learned that finance is actually very simple, but it's made to look complicated to justify fees.

I've learned that self-interest is the most powerful force in the world. People in unethical, predatory, and nonsense jobs will do mental gymnastics to convince themselves they're doing the right thing. Those who criticize the behavior of "greedy Wall Street bankers" underestimate their tendency to do the same thing if offered an eight-figure salary.

I've learned that people are twice as biased as they think they are, which is precisely why biases are dangerous.

I've learned that unsustainable things can last years, even decades, longer than people think.

I've learned that those who think "it's different this time" are the four most dangerous words are wrong. It is always different this time, as no two recessions, recoveries, or market cycles are alike. What's dangerous is assuming the future will perfectly resemble the past.

I've learned that journalists' need to write far exceeds the number of things that need to be written. No writer can say to their boss, "There's nothing important to write about today," although it is the truth most days.

I've learned that no one cares how accurate pundits' forecasts are. Those who listen to pundits are most interested in having their own views confirmed. Accuracy is an afterthought.

I've learned that there's a strong correlation between knowledge and humility. People who spend 10 minutes on Google studying monetary policy think they have it all figured out, while people with Ph.D.s and decades of experience throw up their hands in frustration. The more you study economics, the more you realize how little we know about it.

I've learned that what looks like tomorrow's biggest threat almost never is. Most of what people worried about over the last five years -- inflation, rising interest rates, a double-dip recession, stagnant markets, Greece leaving the euro, a government default -- never occurred. The biggest actual risk for most of us was something few talked about: excessive pessimism.

I've learned that data can do more harm than good. There is so much data available today that you can convincingly prove almost anything by cherry-picking with industrial strength. This breeds confirmation bias, as people start with an answer then find data to back it up.

I've learned that a willingness to wait longer than other people is your biggest natural edge. If you can think about the next five years while everyone else is fixated on the next five months, you have an advantage that makes high-frequency trading, insider tips, and corporate loopholes look like a joke.

I've learned that we can't tell the difference between luck and skill. Out of millions of investors, a few will be phenomenally successful due to luck alone, yet no one is willing to admit they are one of the lucky ones.

I've learned that there's no such thing as a normal market or a normal economy. Some people spend their lives "waiting for things to get back to normal" without realizing that stocks and the economy are always in some state of craziness.

I've learned that when it comes to earning high investment returns, market volatility is like an entrance fee at an amusement park. But few investors want to pay the market's entrance fee. They'd rather sneak in the back door, hop the fence, and outsmart security -- all of which is stressful and likely to fail. At both the amusement park and in investing, they'd have a better experience if they just paid the damn entrance fee.

I've learned that Winston Churchill was right when he said, "You can always count on Americans to do the right thing -- after they've tried everything else." Congress is a basket case 99% of the time, but when things are truly at the precipice it gets things done.

I've learned that people's expectations grow faster than their wealth. The country is richer than it's ever been. I don't think it's as happy as it's ever been.

I've learned that how you reacted to past bubbles is a good indication of how you'll act to future ones. The same people buying dot-com stocks in 1999 were buying Miami condos in 2006 and gold in 2011. 

I've learned that "do nothing" is the best advice for almost everyone almost all the time.

I learned that Godwin's Law is totally accurate.

What about you?

Check back every Tuesday and Friday for Morgan Housel's columns on finance and economics. 

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