Alexander The Great

February 10, 2009

Human Language vs SQL Computation

Filed under: Science — alexanderthegreatest @ 11:26 pm
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SQL Server offers a number of ways to get at your data. You don’t explicitly choose – it has options, and it picks the most applicable data access method for a query and the structure of the data. I think our state of the art knowledge of cognitive science doesn’t understand the specifics, and I was thinking about how this works as an analogy.

  1. Table scan – An entire table is read from disc, slow by slow, and evaluated against the query request. Ignoring the downsides, this is the most broadly applicable method in the toolkit. Any query could be satisfied with table scans.
  2. Index scan – Generally a range scan. In a customers table, this would apply to a query for all customers whose last name begins with a C. An index is a b-tree, so the server will traverse it, reading only the necessary parts, get the locations for the physical data rows, and read them, and only them, from disc. Obviously this is preferable, but not always possible.
  3. Index seek – Usually a single, particular row is demanded, and it’s the only row pulled off the disc. When this happens against a clustered index, you the best performance possible.

It’ll use a mix; if you ask for two predicates (state == ‘ca’ && last_name == ‘kaku‘) with an and, it will perform the most limiting first, then verify only that set against the most permissive. That’s the most economical solution available.

The English language doesn’t have a word for schadenfreude. Usually when somebody says language X doesn’t have a word for Y, you won’t normally lose money betting against them.  The implication is that people who use that language don’t understand the concept being that word, as if Americans couldn’t comprehend the sister of your girlfriend. But what if I said English doesn’t have a word for the sister of your father? You would say “That sounds like your aunt.” And you’d have the answer pretty quickly – obviously you’re “hitting an index” and only even considering a fraction of the words available that might mean that.

Could you do something like a table scan of/in the mind, if you wanted to? Say you want to list all the words you know, or even the names of all the people you know? I don’t think that’s possible. It’s not because we forget – this stuff comes back instantly, in context.  It just doesn’t seem to be organized to be available out of context.

December 8, 2008

The Orb

Filed under: Cool Site,Science — alexanderthegreatest @ 6:40 pm
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From TED – This was created with a noble purpose in mind, and I’d encourage everybody to learn more about it. This, also, is a fascinating piece of technology. The Orb turns a handful of LED lights into a display of our home, Planet Earth.

Nick and James Sears have taken up Fuller’s geo scope challenge, and built a way to contextualize the world’s data.

The Orb

This is truly fantastic.

October 9, 2008

The Uncertain History of Life on Earth

Filed under: Evolution,Science — alexanderthegreatest @ 8:57 pm
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Might there be life on other worlds?

We know the deck is stacked against life coming into being from non living molecules. We know this because it doesn’t happen very often – not last week in Denmark, or the week before, and not in the laboratory. In fact, it’s only taken hold once.

Erasmus Darwin suggested that all living things are cousins, that life is a continuous filament stretching back to the dawn of time. My sister and I have a common ancestor – we share parents. My uncle and I, also, have a common ancestry, this time stretching back 2 generations. But if we go back a million million generations, the family gets bigger – my neighbor’s dog, the local redwoods, whales that swim off the coast, and house flies all share a common ancestor with the E Coli bacteria. We know this because all living things pass their genetic code around in RNA, use the same 20 amino acids, and build polymer chains by adding groups of three atoms, then removing one. All of these picky quirks, and many others, point convincingly toward inheritance.

But the odds aren’t that against genesis. Primitive Earth was a hellish ball of molten rock and lead, constantly bombarded by asteroids the size of Texas. As the planet cooled, extremaphile life may well have began, and been wiped out by these types of “sterilizing” events (this is one theory, with little hope of ever being verified). After the Hadean era, prebiotic Earth was solid and stable enough to support life, at least in principal, around 4.1 billion years ago. There’s questionable evidence of bacteria from 3.85 billion years ago, although the artifacts may not be relics of biology. In any case, living things took no more than 2 to 3 hundred million years to become abundant.

Heavy bombardments forming Earth

Heavy bombardments forming Earth

That’s long compared to a human lifetime, to be sure, but it’s very fast in geological time. Life took hold very quickly. Given favorable, or at least tolerable conditions, Earth did not have to wait long. Hast might just be the luck of the draw (the environment certainly was), but this does suggest that genesis isn’t all that unlikely to happen. Given enough time and resource, the laws of chemistry may even want life to come forth. (This is entirely in keeping with my faith that God loves us all, and set the universe up to breathe life into itself.)

Eukaryota

Eukaryota

If this were the case, given the incomprehensibly vast number of planets and moons sprinkled through the cosmos, by all rights life must have come into being elsewhere. We’ve never observed it, and we never will – the great distances between stars means we’ve certainly never been visited. But the number of opportunities for it to arise on trillions of planets over 14 billion years means we should be shocked if we truly were alone in the universe.

“A sad thought is that life is probably relatively common, but yet so rare and separated by such distances, that no two outposts of life might ever encounter each other.” -Richard Dawkins

For further reading, see the Iron Sulfer World theory that life may have started in hydrothermal vents in the ocean floor, or the RNA World theory that genetics predated metabolism. In any case, abiogenesis research promises insight into the most important questions about our place in the cosmos.

Geologic clock

Geologic clock

July 21, 2008

What Does This Look Like?

Filed under: Humor,Modern Life,Science — alexanderthegreatest @ 10:19 pm
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Clades of the Christian Church

A clade is a branch (from the Greek).  Modern usage has this depict branches in a tree, and cladistics is the taxonomy of the tree of life.  Here is the source of the paradigm the chart above fits into

Phylogenetic tree of life

The tree of life

The circle is merely to conserve space – no metaphysics necessary. Notice how at the 5th and 6th level branchings, we se the beginnings of the pattern in the first chart, the one of Christian history?

Am I the only one who appreciates this irony?

Here’s a similar view of Linux distros – notice the children of Ubuntu

Linux

The idea is quite useful, because most things in our world fit into some type of hiercharchy, which lends itself to being shown as a tree. I’m a Christian myself, but I find it very amusing that Christian church history itself can be described by a series of 2 way forks – a perfect cladogram.

July 1, 2008

Only Use 10 % of our Brains = Myth

Filed under: Science — alexanderthegreatest @ 10:45 pm
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“Nature encourages no looseness, pardons no errors”
–Ralph Waldo Emerson

This is a popular (nay, undying) urban legend, that humans only use some minute fraction of our brains. Usually it’s around 10 %, but 8 and 4 % are also common. Where did these numbers come from? Literally, from nowhere. The central nervous systemIt’s always been clear as day to me that this whole idea is foolish, but now I’ve found the origin of the myth. We’ll get into that, after exploring the reasons this can’t possibly be true.

Humans use all of their brains

Evolution is about being just good enough. Looking at the end result it doesn’t always seem that way, but it’s true. Our eyes are wondrous pieces of technology, far beyond our capability to invent or build. But they’re also prone to myopia. But that’s almost a metaphoric example, introduced to show that marvel isn’t always perfection.

The reason evolution wants creatures to just get by is purely economic. Natural selection punishes anything that isn’t fit enough, but too fit means investing too much energy, time, and other precious resources into something – this, also, is punished by selection. A cheetah who needed twice as much food as normal to build muscular legs to run faster will have less (or no!) children than its brother who runs more slowly, but also escapes predators.

Our brains total about 1.5 % of our body weight (this varies widely), but consume 20 % of our energy, which means our brains consume 20 % of the calories we eat in a day. This was a radical experiment! Selection would never allow this, unless the brain gave a tremendous return on investment.

The brain is broken into a number of discreet parts with specialized functions. We know this from a long history stretching back to Phineas GagePhinneas Cage, a railroad worker who survived an iron rod more than an inch across and 7 inches long, being blown through his head. Amazingly, the man was able to speak within minutes, and to sit upright while being rushed to the hospital. His friends would later describe him as “not Gage” – his personality was instantly and forever changed. Phineas had trouble walking for much of his following life. In fact, we know a tremendous amount about brain function localization (see Ramachandran), and we know every “piece” has a role to play. Functional magnetic resonance imaging (fMRI) confirms this, even in sleep.

Where did this come from, then?

Although the numbers change, this myth makes very specific descriptions – we use a particular amount of our brain. This leaves open the possibility that the remaining 90 % (or 92 or 96 %, etc) of our brains might allow us to fly, if only we could tap in! So, how do we come to this idea at all, and this number in particular?

In the 1930s, a general scientist named Karl Lashley experimented by cutting lesions into rat brains. Even missing a piece, the rats could survive, and relearn important functions. (This is explained by neuroplasticity.) Having removed many different parts of many different brains in many different rats, it seemed evident that none of them were truly required. On the other hand, if you were to remove all of these pieces from the same brain, the rat it lived in would surely die! Rather, the functions being studied were so vital, that they could be moved from one area to another inside a maleable brain.

We can learn from these experiments that a certain amount of redundancy is built into the system, for safety reasons.

What does it even mean?

What does it mean to use X % of one’s brain, if X doesn’t equal 0 or 100? There are many different ways a person could interpret this, but I don’t think any of them are agreed to? I doubt anyone who repeats this myth even gives it much though.

A typical neuron

June 26, 2008

Who or What is a Native American?

Filed under: Evolution,Science — alexanderthegreatest @ 9:11 pm
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Am I? It sounds like a dumb question, both the title of this post, and whether I’m a Native American. After all, my family came here from Russia. But I was born here, in California, as were my parents. (That’s not true – my father was born in Pennsylvania.) More or less by definition, I’m not only native and American, but I’m a native and not a naturalized American. The only sense I can’t properly call myself a “Native American” is the sense in which that phrase has taken on a specific meaning. One that doesn’t include me.Sitting Bull

I see three possible ways to define a Native American, and we’ve just struck one of them down.

  1. Being born in America, perhaps anywhere in the New World.
  2. Being of the line that became human in the Americas. In this sense, we’re all Native Africans, and we’re all equal.
  3. Being descended of the first (or first surviving) humans to reach the Americas.
  4. Being of the same “race” as anyone we would collectively term a Native American.

The racial definition (#4) is the one we share, and not very much unlike #3. The differences are subtle, but interesting. Most westerners would say #3 is the correct answer, and interestingly, it takes us back to silly #2. How is this possible? Let’s ask another question.

Who Were the First Americans?

This is a hotly debated topic, although much of the controversy has been settling down. There are two possible explanations (three if you accept the Mormon doctrine that the Garden of Eden was in Missouri). Either the first humans to set foot in the continents of the New World were Siberians crossing the Beringia steppe, probably in pursuit of large game, or they were Australians or Polynesians who survived a disastrous mistake and whose descendants have been driven almost to extinction in Tierra del Fuego.An mtDNA based migration map

There are uncontested artifacts from human settlements in Alaska, from about 13,000 years ago. In fact, there are many. What this means, is that nobody can doubt people really did cross Beringia, the Bering Land Bridge. But were they the first to set foot here?

In the most extreme example, a single pregnant woman with a male fetus may have survived an accidental journey to South America from Polynesia. The first use of boats must have happened around 30,000 to 50,000 years ago, by people reaching Australia from southern Asia. This wave of human expansion – the first to reach new land, never reached by our protohuman ancestors – continued to New Zealand and surrounding islands.

Many of the tribes on these islands kept in contact with their neighbors, sometimes near and far. It’s unlikely, but entirely possible, that one of these boats, aimed at a not too distant island, lost its way. Possibly in a storm – Polynesians today can read the waves and “sense” islands over the horizon the way many can read a face and see anger or anxiety. Ancient Polynesians traveling by sail and by oarThis is a finely honed skill, almost certainly not available in those ancient times. And yet, we should remember we’re talking about the world’s first sea farers. Even then, probably a large group set out, and a very small one survived the journey, if such a journey ever happened. When they landed, it was on the distant shores of a New World.

This “founder population” peopled the lands, and then was wiped out almost completely.

Most of the supposedly pre Clovis finds are in South America (Chile, Brazil, etc), as we’d expect. Monte Verde has been one of the more operatic chapters in our story, but is today widely accepted to have predated Clovis by at least 1,000 years. Humans lived in this part of Chile maybe 14,500 years ago. Among these finds are not only tools, but aloso human skeletal remains. Skulls found at many of these sites clearly resemble Australians, rather than the Mongolians who would become “Amerindians” of today. Mitochondrial DNA is ambiguous here, but modern day Tierra del Fuegans could be descended directly from the Polynesians they so closely resemble.

There are few of the coastal settlements we would expect to see on a “new” continent being populated by sea going people. Of course, this was during the last ice age, when much of the Earth’s water was locked in glaciers. The sea level was at the time much lower, so ancient coast we’d expect to find these sites near is underwater today. We need scuba divers to thoroughly explore the area!

What of the Bering Land Bridge (Beringia)?

The Bearing Sea today is about 50 miles at its narrowest point, and an average depth of 400 feet at its deepest. During ice ages, as we’ve seen, the waters retreat and lowlands rise up from the sea. The channel between Siberian Russia and Alaska opens up this way, exposing a land mass to connect the continents. This has happened countless times before mankind set foot on the bridge, and it will happen again – just not within our lifetimes.

Canada was a sheet of ice at the time, and not much else. It would be at least a millennium before our heros could cross to the south. When a corridor finally opened, running north by south across the Canadian ice sheet and letting out in the inland plains near Edminton, they found large animals with no fear of humans. These included elephants (well, mammoths, anyway), horses, giant sloths, saber tooth tigers, and more. Camels seem to have evolved here, as llamas, and crossed the same bridge, long ago under a very different climate.

At the all important Clovis site, a mammoth was found with a clearly man made spear tip in its ribs. Wherever mankind went, we managed to eradicate large game species. This is the “megafaunal crisis of the late Pleistocene” when animals that had survived millions of years died out within a few hundred. Giant lemurs, cow sized marsupial cats, and others have fallen victim around the globe, and it would be a surprise if we didn’t see it accompany the colonization of the New World. So why don’t we see this on the same scale in South America?

In any case, the Austronesian theory says the Bringia crossing was one way people came to the Americas, possibly out of many.

A time animated map of Beringia

Who Deserves to be Called Native, Then?

Personally, I’d say anyone born or raised in the Americas, but I’m probably trivializing the question. If the hypothesis is true that the New World was peopled through successive migrations, then perhaps all of their descendants should be called natives. Or none of them, since all came from somewhere else, ultimately. This is probably the wrong answer, though, because some level of evolution continued for many thousands of years, adapting people to their environments.

June 12, 2008

Is Spam the Dominant Species?

Filed under: Evolution,Science,Software — alexanderthegreatest @ 12:09 am
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A friend told me we should round up all the spammers, and throw them off the Golden Gate Bridge, down to the sharks below. Trouble is, others will take their place. Spammers, sadly, aren’t a hereditary breed – it’s a learned behavior. (Almost Lamarckian!)

Even if you don’t agree about where spammers come from, we’ll have to agree there are too many of them. Spam is a very successful meme, a unit of cultural information that’s better than most at copying itself. In the realm of intellectual selection, spam is to be found far and wide in the meme pool. Spam is maybe a parasite working on (or against?) the get rich quick meme – if people stopped wanting a quick and easy buck, spam would vanish overnight.

What’s this rubbish about it being the “dominant species” though? We eradicated small pox, a more difficult and more important thing than going to the moon, and we’re losing the war against spam. It’s beating us. America gave fire water to the “Indians” to take their land – now, in some places, native casinos are using greed to take modern culture’s money. Spam is doing much the same thing.

Spam is a concept, an idea, that by producing a lot of useless drivel, a person can strike internet riches. It comes in a few varieties, from the email sitting in your box, selling you viagra and mortgages, to the affiliate and “search engine friendly” links in a forum and a blog. It’s PayPerPost, where a blogger can beat the 1849 gold rush by telling you how wonderful a sponge and a bank account are. It’s Digital Pointless, where you can buy other people’s Wikipedia and eBay accounts. Fine, that’s what spam is, but what are we? It’s hapless accomlices, we’re machines, some of us, that spam uses to copy itself.

All of this is Darwinian. If you have variation (spam, job, investment, invention), heredity (new spam is very much like old spam, but refined in its sales pitch or its delivery) and selection (spam filters, forum moderators, people seeing through it), you have evolution. This works in biology (genes), and it works in ideas (memes). If you have the struggle for existance among things that copy themselves, the one that’s better at making copies will come to dominate, to fill its world. Ladies and gentlemen, this is exactly what spam is doing – a digital thing filling its internet world. One of the dominant species in the meme pool.

Spam

This proves our point – bad spam, the least fit, failing in the struggle for existance.

June 7, 2008

Amazing Statistics

Filed under: Science — alexanderthegreatest @ 9:02 pm

Of course, that’s if any statistic can be called amazing?

90 % of everybody who’s been alive, has died. We should be happy that aging is the #1 cause of death, according to Nick Bostrom.

May 22, 2008

The Final Frontier – The Oceans

Filed under: Science — alexanderthegreatest @ 11:08 pm
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Almost a quarter (23 %) of our planet is a single mountain rangle. Mars is mapped in more detail than our most extreme geographical feature. Beneath the surface of the ocean, deep, deep under the water (in some cases, miles) is a world more bizarre than any in Star Trek. Unimaginable. Almost for certain, we can assume this place is beautiful beyond words. Except that light doesn’t penetrate into the depths.

Almost 3/4 of our planet doesn’t feel the warmth of the sun. This is a bit of an exaggeration – if it truly didn’t feel any warmth, it would be absolute zero, as is much of deep space. Still, the point remains. It’s almost unfathomable that life could be in a place like this, let alone flourish.

Watch the video – it’s incredible.


Creative Commons, too.

Talks Robert Ballard: Exploring the ocean’s hidden worlds

Edit: Embedding the video doesn’t mesh with WordPress.

April 13, 2008

David Vitter Continues Humiliating Christians

Filed under: Americana,Modern Life,Science — alexanderthegreatest @ 11:53 am
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David Vitter is the right wing extremist senator from Louisiana, obviously a Republican. He earned national fame when his was found in the “DC Madame’s” client book. Mr Vitter loves the prostitutes every bit as much as Elliot Spitzer – the difference is that, like Larry Craig, Vitter lacks the decency to step down.

Vitter proposed and then withdrew an earmark (because conservatives love those) to integrate church and state

Speaking on the Senate floor on October 17, 2007, Senator David Vitter (R-Louisiana) withdrew a controversial $100,000 earmark that he previously added to the appropriations bill for the departments of Labor, Health and Human Services, and Education. The earmark was to the Louisiana Family Forum, a religious right group with a long history of promoting creationism and attacking evolution education in the state, including backing a “strengths and weaknesses” policy in Ouachita Parish.

Look, I’m a Christian myself. I’m also an American. We’re losing our competitive edge in the world. Let the schools teach Earthly reality, and let the churches teach about the next world.

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