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Archive for the ‘science’ Category

The ‘Great Filter’: I Wish Stephen Jay Gould Were Still Alive

Posted by samgr on May 15, 2008

So there’s a really interesting article in the MIT Technology Review by Nick Bostrom which basically argues that finding evidence of extraterrestrial life in our own solar system would be the worst thing that could ever happen to humanity.

Loosely the argument is this: we now know the galaxy is full of planets, so the fact that we’ve seen no evidence of extraterrestrial INTELLIGENT life means that there is likely some kind of “great filter” that precludes the advancement of civilization to the point when it can colonize or otherwise broadcast its existence to the rest of the galaxy. If the great filter is in the past from a human standpoint—i.e. if it’s very hard for life to evolve complexity or intelligence, or even for life to arise in the first place— that’s good news for us. We’ve already passed through the filter because we’re lucky and awesome. If it’s in our future—i.e. if there’s some technological discovery that tends to wipe out civilizations (don’t switch on the LHC!!!)— then we’re in deep trouble. We’re unlikely to be the first civilization to make it through the great filter.

So, says Bostrom, if we find life on Mars or Europa, that’s bad news. The more advanced the life is, the worse news it is. If life evolved independently somewhere else, it’s statistically much less likely that the filter is in the past. So the expected lifespan of human civilization gets a lot shorter.

Now some thoughts from me. This all ties in with a lot of what Stephen Jay Gould writes about in Wonderful Life. He doesn’t use the “great filter” terminology, but he argues pretty forcefully that evolution of life on Earth is wildly improbable. He doesn’t seem to think that the ORIGIN of life is that wacky though; it’s more that the transition from unicellular to multicellular organisms is very hard to achieve, and that the evolution of intelligence is in fact very unlikely.

So from Gould’s point of view (I would think), if we were to find some slime on Mars or even some jellyfish on Europa, that’s not quite as much of a disaster as Bostrom thinks it would be. Bostrom leans toward the great filter being the initial origin of life, where what Gould writes suggests that the filter is more likely one of the transitions along the very unlikely path from slime to us.

Another thing that interested me in Bostrom’s article was this passage:

“Now, it is possible to concoct scenarios in which the universe is swarming with advanced civilizations every one of which chooses to keep itself well hidden from our view. Maybe there is a secret society of advanced civilizations that know about us but have decided not to contact us until we’re mature enough to be admitted into their club. Perhaps they’re observing us as if we were animals in a zoo. I don’t see how we can conclusively rule out this possibility.”

This has always been something I’ve wondered about. To me, this seems almost as likely a solution to the Fermi paradox as the great filter dealy, but it’s true that there’s no real way to prove or disprove it for now. Something’s going on, in any case.

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Posted in aliens, evolution, science, space | 1 Comment »

Titan Ocean! OMG!

Posted by samgr on March 20, 2008

I try to avoid writing posts that are just a link and commentary, but this is really cool. Analysis of Cassini data suggests that there might be a liquid water ocean under Titan’s mushy surface. If this is true, I think Titan just scooted in front of Europa as the best possible place to look for extraterrestrial life in our solar system. Titan is full of organic molecules, and the combination of organics and warm(ish) liquid water is pretty hopeful.

The downside is: how are we gonna build stuff there now? I’d always liked the idea of Titan as a place to colonize- Earthlike atmospheric pressure so we can build huge domes, availability of chemicals needed for agriculture, etc. But that’s no good if when we try to build a house on what we thought was the surface, it’ll sink through the crust with a loud SHLOOP and disappear into several miles of ocean. D’oh.

UPDATE: According to the NYTimes, the icy layer on top of the ocean is actually 50 or 60 miles thick, so maybe it’s not so much of an issue that things will shloop through it. Also, this says that Europa is still a better bet for life because the water has contact with volcanic rock, which would provide an energy source. What I don’t get is that if the water on Titan ISN’T heated by the core, where does the heat come from and why is it liquid…

Posted in science, space, Titan | 1 Comment »

Here’s an Important Question…

Posted by samgr on March 19, 2008

So here’s an important (but possibly dumb) question. How much radiation does melanin shield you from? What I’m getting at is this: let’s say a gamma ray burst hit the earth and wiped out a lot of our ozone layer. Would people with darker skin be better protected? Would humans all evolve to be black? Someone please answer this; I was wondering about it in the shower.

Also, let’s say we colonize (and maybe terraform) Mars. Since it has lower gravity and much more radiation, would Martians end up looking like Masai: really tall and really dark? Or is that a totally different kind of radiation than the kind melanin blocks?

Posted in Mars, science, space | Leave a Comment »

James Watson is a Startling Douchebag

Posted by samgr on October 20, 2007

And the world has finally woken up to that fact. The Double Helix pissed me off more than almost any other book I’ve read. (Still champion: Bobos in Paradise. Die in a fire, David Brooks.) The whole story of Watson’s life is like if Tucker Max won a Nobel Prize. He’s a terrible person with one lucky break, and he somehow coasted off of it for the rest of his life. And this particular situation is one of those weird things where outrageous misogyny is somehow acceptable, but outrageous misogyny combined with racism pushes it over the edge.

Apparently I’m in a bad mood today.

Posted in books, David Brooks, James Watson, misogyny, news, racism, science, Tucker Max | 3 Comments »

Stuff I Wrote for Another Site

Posted by samgr on February 21, 2007

Check it out:

Jellyfish
Contraption: Part 1
Space Speeches
Contraption: Part 2

Posted in language, Open Source, science, sea life, space, technology | Leave a Comment »

Optimism

Posted by samgr on January 11, 2007

On the eve of the new year, the website edge.org invited over 100 scientists to contribute essays answering the question: “What are you optimistic about?” On January 3rd, NPR’s Radio Open Source aired a show on the subject, asking a few of the thinkers who contributed their essays to talk about their reasons for optimism. Here are some of my reactions to the show.

One of the guests was Harvard psychology professor Steven Pinker, who argued that we can be grateful for the gradual decline of violence over human history. I found his argument convincing, although not necessarily as cheering as it might have been. When asked about the incredible levels of modern violence that we see in the news every day, Professor Pinker pointed out there was even more violence in past eras of history, just that people were less aware of it. Fair point, but that’s some awfully depressing optimism. I also noticed a parallel between the reasons that Professor Pinker suggests for the decline of violence, and the writings of modern philosopher Richard Rorty. In his essay, Professor Pinker suggests that the trend could be caused by the increasingly inescapable logic of the golden rule, and adds:

“Perhaps this is amplified by cosmopolitanism, in which history, journalism, memoir, and realistic fiction make the inner lives of other people, and the contingent nature of one’s own station, more palpable—the feeling that ‘there but for fortune go I.'”

Steven Pinker, The Decline of Violence, Edge.org

This sounds a lot like the expanding “circle of the we” that Rorty describes in Contingency, Irony, and Solidarity, where people become more aware of the feelings of others and more invested in preventing cruelty when they are exposed to descriptions of more and subtler kinds of cruelty, which can be found in novels and other types of literature.

Another guest was Chris DiBona, who works at Google, and predicts that the increasing availability of high definition online maps and images “will end conflict and ecological devastation as we know it.” The idea is that when we can all see all of the nasty instances of rapine and murder that are going on, we will work harder to stop them. I certainly hope this is the case, but Mr. DiBona didn’t really have much in the way of evidence to support his prediction, which was more noticable than it would have been otherwise, since his segment of the show followed another segment in which Clay Shirky talked about the increasing importance of evidence-based reasoning in human history. Oh well.

My favorite guest was Paul Steinhardt, who talked about some of the exciting technology-driven innovations in physics and cosmology that he expected to come about within the next five years. His optimism was very easy to get caught up in, since he offered up potential discoveries and answers to nagging questions that it was reasonable to assume might come in the near future. I want to know why we haven’t heard more about some of this stuff in the news, and I look forward to following some of the described projects in the next few years.

Finally, all of this reminded me of the best-written explanation of the fundamental optimism of scientific progress that I’ve ever read — the short story “No News, or What Killed the Dog,” by Ray Bradbury, who is also known for his dystopias. Can’t find this on the internet, but everyone should try to read it if they have a chance.

Posted in futurism, internet, Open Source, optimism, Richart Rorty, science, Steven Pinker, violence | Leave a Comment »

Prehistoric Creatures: the Liopleurodon

Posted by samgr on January 8, 2007

UPDATE: Read this post.  Enjoy it.  But if you LOVE liopleurodons (and who in the name of Sam Hill doesn’t), you should check out my new blog project here: http://calamityblog.wordpress.com/

You will not regret it.  Now back to your regularly scheduled post.

This will be the first of a series of entries on prehistoric creatures that I think are relevant to modern life.

Lio

Liopleurodons will probably never be as popular as woolly mammoths and t-rexes, and their name doesn’t exactly roll off the tongue, but this giant sea reptile seems to have entered the public consciousness a bit more lately. This can probably be traced to two things:

1. The inclusion of a big scary liopleurodon in one of those BBC-produced “Walking With Dinosaurs” TV-shows a few years back; looking cool and doing improbable things like leaping out of the water and devouring large dinosaurs.

2. A recent cameo in a upsetting cartoon.

This is all well and good. I like liopleurodons. I am skeptical, however, of the sloppy science that the “Walking With Dinosaurs” people employed to make their liopleurodon size estimates. Based on the liopleurodon fossils that people have found, the animals probably got to be about thirty feet long. This is pretty respectable, I think. However, the “Walking With Dinosaurs” folks depicted their liopleurodons as seventy-five feet long, based on a chain of dubious logical leaps. (A sea reptile fossil was found in Mexico in 2002 that was about forty-five feet long. It probably wasn’t even a liopleurodon, but people briefly thought that it might be; what’s more it seemed to be a juvenile, so whatever it was might have gotten even larger with full growth. This was good enough for the television show to report with the appearance of authority a wildly inflated size estimate for their liopeurodon.)

This sort of thing bugs me. I think that giant sea reptiles are cool enough already without dumbing down the science to tell me that they were far bigger than they actually were. Prehistoric monsters are more interesting to me than the Abominable Snowman, say, because prehistoric monsters were real and the Abominable Snowman is not. So I want to know about scientists’ best guesses about what is true. If these shows are ostensibly about education, they should use good science, and not cave into the principle of stating whatever sounds coolest from the range of what is conceivably possible. And it’s not like giant toothy sea reptiles are lame or garden-variety if they are ONLY thirty feet long.

And now in sources like the web, misinformation will propagate, because most people will write down and repeat the most impressive version of the facts they hear. A similar thing happens with another real, but non-extinct animal: the giant squid. Since stories about giant squids tend towards hyperbole anyway, even sources that proclaim to be scientific throw around inflated size figures more or less solely because people think that bigger monsters are cooler monsters. They’re cool enough! I think there is no need for exaggeration.

(The author Richard Ellis has written two very good books — one about giant squids and one about prehistoric sea reptiles — that provide rigorous and non-flighty looks at both of these very large sea creatures. Fun to check out, and they stick to real science.)

In a weird way, this relates to what bugged me about Al Gore’s movie, An Inconvenient Truth. I should get it out of the way that I think the film was extremely well-motivated and provided a vitally important public service. But at the same time, it bothered me that it dumbed down the science: showing graphs without labeled axes, and not going into any depth about how the data being talked about was obtained. After seeing the movie, I read the book The Weather Makers, by Tim Flannery, and the contrast was quite striking. The book made pretty much the exact same points as Gore’s film, but made them by letting the reader in on the science that can get us to those points. When an author or filmmaker assumes intelligence on the part of the audience, a better and more thorough case can be made.

On the other hand, Gore’s film seems to have made an impact where many other projects simply could not, clearing away some of the manufactured arguments against the crisis of human-influenced climate change. So am I giving the public too much credit? Am I just being a snob? What do you think?

And that’s why I like liopleurodons.

Posted in climate change, prehistory, science, sea life, truth | 4 Comments »