Eggnog ruminations

So... all our oil and coal originates from plant and animal matter, right?  Living stuff was buried over millennia, compressed and reduced and cooked until all that remains is a sludge of hydrocarbons: long branches of carbon bursting with hydrogen atoms like ripe fruit ready for the fiery picking.

And our industrialized, world-changing society was built on finding these puddles of free energy, just lying there*.

So what if we, or a race like us, rose up in the Cretaceous?  The first abundant complex life on earth rose up at the end of the Proterozoic Eon, around 600 million years ago; but the Cretaceous period, where there's massive complex animal life in the form of dinosaurs and other beasties was around 100 million years ago already.  Would there be oil to find, to fuel their own industrial explosion?

I had this sudden image of velociraptors learning to herd smaller, dumber dinosaurs; setting up colonies and competing nations; languages, philosophies, dances about the hunt.  Their brains grow, they make fences and weapons, they discover surface metals and learn to shape them.  A rich and flowering culture emerges, celebrating their prime and central place at the top of the foodchain.

And it all just sticks around until it goes kablooie with the asteroid impact, because there's no oil to fuel a truly industrial velociraptor society.  Their theropoda alphabet fades, unfossilized, the writings of Velocishakespeare and his violent (but hilarious!) comedies vanish.  The universe murders their society in cold blood, and you can't do anything about it unless you have a space program**.

Of course, this probably didn't happen.  We would see fossilized pipes and predator bling at least; and the oil was probably there already anyway, with 500 million years to develop.

But that just begs another question: why are we the first species on Earth to tap into all this stored energy and have a chance of spreading away from our home planet?  That's hard to say.  Maybe pure predators just have an intelligence cap, or a population cap, and intelligent species are much more likely to develop from animals with general ability (i.e. fingered omnivores).  Maybe the exact evolutionary pressures that lead to intelligence are rare, so it's a one in a billion chance.  Maybe other lingual species have existed, but didn't develop tools (or leave tools in the fossil record) and were wiped out before they spread.   Maybe intelligence is SO rare that its impossible except for uplift***.

Maybe we are inevitable.  And maybe, we are special.

Have a Merry Christmas!

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"Man becomes man only by his intelligence, but he is man only by his heart."
-Henri Frederic Amiel

* not necessarily true: most of the structure for our world-changing civilization was already in place well before industrialization and the primacy of oil.  Metal-based civilizations arose with just wood for smelting, and there was plenty of wood in the Cretaceous.  But stick with me for a moment.
** Take a look at some groups that are actually working on this problem, as well as many other potentially earth-shattering or catastrophic possibilities for life as we know it, at The Lifeboat Foundation.
*** also comes in futuristic space opera flavor!

update re: Tidal energy

Part of why physics is fun is that it lets you put numbers to off-the-wall concepts.

For instance, I mentioned a couple of posts ago that if you use the tides to make electricity, you are actually taking energy out of the Earth's rotation, making the day longer.  But by how much?

You can start by calculating the energy stored in the rotation of the Earth.  As a freshman in college (if you take physics) you learn that there's a quantity called Rotational Inertia (I) for solid bodies that behaves like normal inertia (mass).  So, where energy for linear motion is E = (1/2)*(mass)*(velocity)^2,  energy for rotational motion is E = (1/2)*(I)*(rotational speed)^2.  And you can calculate I for any geometry of solid.

For a rigid, uniform sphere, I = (2/5)*(mass)*(radius)^2.  Earth is neither rigid nor uniform, but we'll assume this is close for now.

Then with the magic of Google Calculator, you can just plug all these in for the earth and get it's rotational energy.  Seriously, copy-paste this into Google:

" (1/2)*(2/5)*mass of earth * radius of earth^2 * (2*pi / day)^2 in gigawatt*hours".

It will tell you that the Earth stores about 7*10^16 gigawatt-hours of energy.  Google calculator is so magic.

Well, the US uses 30,000 gigawatt-hours of energy a year.  So the annual energy usage of the US is about 0.4 billionths of the energy stored in the rotation of the Earth.  If you take that amount out of the Earth's rotational energy, you can use the energy formula in reverse to figure out how much the Earth slowed down.  The answer: 18 microseconds (that's 18 millionths of a second).

So there you go.  If you run the entire US on tidal energy, you slow the Earth's rotation down by 18 microseconds each year.  Amazingly, this is almost exactly the amount of slowing that is measured to occur naturally due to torque from the Moon (17 +/- 0.5 microseconds/year).

Obviously the aliens living inside the hollow sphere of the Earth are powering their invasion bases with tidal power.  It's the only explanation.  Don your tinfoil hats!

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"Someday, after mastering the winds, the waves, the tides and gravity, we shall harness for God the energies of love, and then, for a second time in the history of the world, man will have discovered fire."
- Pierre Teilhard de Chardin

Tangent: all energy is fusion energy

...at some point in its life-cycle.  Check it out:

• Solar:  Deep in the sun's core, all that gravitational pressure compresses hydrogen until it's just so energetic and dense that the protons fuse together to make a deuteron (a nucleus with proton + neutron).  Then the deuterons fuse with each other to make tritons (1 proton, 2 neutrons) or Helium-3 (2 protons, 1 neutron) and so on up the long ladder.  As it turns out, the particles like company: so at each step, as you're building bigger and bigger nuclei, you get a little bit of free energy out.  It's like the protons are getting all excited at coming together with their friends so they start throwing a hell of a party.  All those little parties heat up the sun yellow-hot and it radiates light to space - to us.  That's sunlight.  This has been going on for four and a half billion years.  
• Wood, tomatoes, hamburger buns:  Plants are nature's solar cells: they eat light.  Unlike our solar cells that make conducting electrons, plants turn it into sugars and starches, and use it to build vitamins and proteins and cellulose.  (If plants were crystalline or metallic, they might use electricity directly: anyone good at genetic engineering?)  Eating plants, you get to metabolize all that energy; burning them, you get beautiful toasty fire.  And fire and sugar are stored sunlight - and sunlight is fusion power.  QED.
• Coal, oil, natural gas: biomass, concentrated, heated and pressurized until made delicious to jet planes and locomotives.  Nothing new here.
• Meat: just processed plants, buddy.  Super delicious, super inefficient.  next:
• Wind: That's right: wind is solar power, and therefore fusion.  Weather systems are generated by temperature differentials on the globe north-south and across the terminator (excuse me, the terminator).  And what causes temperature differentials?  You guessed it!  (in the background, there).

So that's all pretty straightforward and obvious.  Here comes the tricky part.  Lets do this.

• Nuclear Fission: Fission power is fusion power.  

Wait (says you), that's oxymoronic, you... oxymoron.  Fission is the exact OPPOSITE of fusion.  Instead of getting energy out by building up heavier atoms from light ones, you get power by breaking down super-heavy atoms, like Uranium.  

(aside: why do these both work?  Well, protons & neutrons have a limit to the size of party that they enjoy.  When the crowd in a nucleus gets too big, they don't like going into it anymore; and you have to give them energy to make them go in.  That limit is actually at Iron, element no. 26.  I guess nuclei in heavier elements are increasingly awkward.)  

But where do those super-heavy atoms come from?  They can't be made by fusion in stars, the stars fizzle when they get to iron.  No:  they're made in supernova.  When a large star runs out of fusion fuel and its core collapses, the resulting burst of energy tears apart some of those nuclei it spent so much time building and bombards the rest with their fragments.  There's so much energy that the protons and neutrons are crammed into these huge atoms like uranium, where they all stare at each other and have long pauses in the conversation.  

So it's fusion that puts all the energy in these radioactive heavy atoms, and that you release in a fission reactor.  Bam.

I think there's a few more:

• Geothermal: The earth is heated by radioactive decay of heavy atoms.  See above.
• Monkeys on bicycles: powered by bananas, powered by sunlight, powered by fusion.
• Magic (literature): powered by the minds of authors, powered by food, etc.
• Magic (real-world): powered by cold fusion. 

• Tidal:  ...

Okay, you got me.  The tides aren't fusion-powered.  Tidal energy is powered by the rotation of the Earth, and the orbit of the moon, and those come from the interstellar dust spinning more in one direction than the other when the solar system was formed, which is pretty much just random chance.  Fun fact, though: if you use tidal energy to generate electricity, you are slowly making the day longer.

So what lesson can we take from all this?  Just one: nucleons are hipsters.

They want to maximize Irony.

And I'm done.