Monday, September 13, 2010

Water Potential Energy, or The End of the Universe and Why You Love It


This entry is about entropy.
First, congratulate yourself. You are a member of a species that is able to do something truly unique on this planet. I'm not talking about building cellphone towers or coming up with terrifying and ingenious ways of getting the stuff we think we need or baking or the propensity to create art or even the tendency to want an objective mechanism of discovery through science.

I am talking about your ability to know and believe contradictory statements.

Tools really aren't that impressive. Lots of animals build tools. We just build tools that build tools. Lots of animals accumulate resources. We just create new resources out of attainable resources that then allow us to easily obtain even GREATER resources that allow us to then create and obtain even MORE resources.

What we do, that is really interesting, and really important, is that we are able to simultaneously know two things to be true, even if they are in direct conflict with each other.

If you are an adult, for example, you know that there are people to whom you matter. You know that your actions have direct consequences on the world that you inhabit. You can burn down your house, you can love your pets, you can do well in school, you can be a terrible murder and these actions will effect your visible world. But if you are an adult you also know this: the world is very large compared to you, and the net effect of your actions is cumulatively zero on the trajectory of the species, unless you happen to be one of the few that are in charge of large numbers of people. Which, if you are reading this, you probably aren't.

But, despite knowing how little you matter, and how little it matters that your children are fed or that your plants are watered while you are away or that you recycle or that you eat that last cupcake in the breakroom despite already consuming between 2 and 3 earlier in the day, we constantly struggle to live as if it does matter.


This is what keeps us balanced and healthy and alive, otherwise we'd just go insane and DIE thinking about what it means that black holes can SUCK IN LIGHT and that there are people in terrible conditions with no help and no love and no food and I'm sitting here eating a god damned panini drinking ice coffee with a flavor shot typing on my little machine that contains at least 5 toxic chemicals probably extracted by terrible corporations who are destroying the world to make my plastic crap that I constantly am having shoved down my throat by the TV that is constantly on in the background and YELLING AT ME while the world is slowly drying up and the honeybee and a million other tiny beautiful things go EXTINCT and cells are dividing and the magnetic poles are quieting the solar storms that will one day overwhelm our invisible defenses and destroy the planet.

It is this ability to hold contradictions in our little minds that allows us to grapple with one of the more difficult and terrifying realizations we must interface with:

Living and dying are the same thing.

On a larger scale (press zoom out) not only are living and dying the same, the end of time and time as we experience it now are the same thing. The end of the universe and the universe as it exists at this moment are the same. What makes one different from the other, is entropy.

How is this possible? Entropy.

Entropy is one of those funny words that we all think we understand, but we really don't. Most people associate entropy with chaos, when really entropy is much quieter than the chaos one envisions when talking about the force destined to destroy (and currently destroying) the universe. Entropy is not the herald for galactic war or going to blow the universe up in a final battle of good versus evil with machines vs man vs god vs aliens vs machines. Entropy, to steal a phrase from Neil Gaiman, is just here to turn off the lights at the end of our universe's long life, long after we have all fallen asleep.

I know you're just looking at the pictures. Its alright.

Entropy is diffusion. It is the consequence of terrible balance and inescapable equilibrium, and it is scary because it is ultimately irreversible. It isn't a thing. It is a place holder for an idea. When I say: entropy will destroy the universe, I am saying the process that we understand to be entropy will destroy the universe.

Here's how it works: energy can't really be held on to. Ultimately it can't be stored or recreated or moved or bargained with or held captive. Eventually all the energy in the universe, like your body heat or heat from stars or electromagnetic radiation, will diffuse completely throughout the universe, and everything will very slowly freeze and stop. Forever. Maybe. The universe is expanding, and the energy is diffusing. Think sand through an hour glass, or one of those toys with the two liquids, where turning it upside down forces the denser liquid through a maze or over a water wheel, but eventually it all settles out again. Our universe only exists so long as those two liquids are moving that wheel. Once they settle out, everything stops. That's why they call it the heat death of the universe.



But how does this work? How is all this energy escaping and diffusing out? Its really not that difficult to understand. You engage with it all the time. Also known as the second law of thermodynamics, this law says that temperature, pressure, chemical potential energy, and water potential energy (to name a few), all move from areas of high "concentration" to areas of lower "concentration." This is why hot things cool, why sugar diffuses uniformly in water, and why energy flows through a system. It also serves as the ideological foundation for osmosis: or the movement of water molecules across semipermeable membranes "down" a water gradient. This is what I mean when I say we can't hold on to it. Your cells are like those little water toys. All those little wheels are attached to other little wheels, and eventually you get the machinery of the body. Those wheel stop spinning, and everything dies. 

Think about food. We put tons of energy into getting food. Food is really just energy that has been slowed down through chemical and physical means by living organisms. We find where the energy has been slowed, and we steal it from other organisms. Although, sometimes they willingly provide it in return for care (think fruit trees). You have to get it quick though. Life on this planet is voraciously seeking out forms of slowed energy, so it doesn't last too long. Food provides us with energy in many different forms, but we can't really store it. Yes, you can go something like two weeks without food but, eventually, you die. Yes you can get fat from all the sugar you try to store, but you'll still die if you don't use that energy to move all those little tiny wheels in your body.

In short, the fact that things flow and this flow can be used to turn little wheels, is a huge portion of the definition of life, although there are other little wheels that exist naturally (that is, without being created by living organisms--think plate tectonics and the rock cycle). 

Sometimes, after a long day of plant physiology, I catch myself staring a things like glasses of water. I know we are convinced that life is all these grand things, like the ability to grow and develop, and the ability to reproduce and procure energy, but, I can't help but think that maybe when we say water is the key to life, we actually mean water is life.

What if life as we know it, is just the myriad of skins water developed to colonize land. The more I learn about what plants are able to do on the cellular level the less I am convinced that brains are not particularly important. Do you know how food is turned into usable energy? Your cells sure do. They know cold even the most complicated pathway to make some complicated protein involving 47 insane phosphorlyation steps that you've never even heard of. Brains can do things like wonder about the universe and the nature of reality, but cells are busy living the day to day grind of keeping us alive without us even knowing it.

The planet seems large, but the planet is really quite small as far as relative size of the universe is concerned. I think it is quite possible that this whole planet is very much like a single cell, and that the brains we have developed are the result of the cell attempting to create a mechanism of unification, or a new weapon against space (which sends nasty things like meteors and solar storms and evil aliens). 

But I digress. This is really what I want to say:

Life is the ability to maintain a gradient (thank you, Dr. Wendy Boss). It is the ability to use the flow of energy through the system to turn a billion wheels on every level of the scale of existence.  

And so cells are able to turn lots of little wheels that do lots of little things just because things flow from high concentrations to low ones. They have specialized membranes that allow them to control the flow of all sorts of different things. The building blocks that they use to make everything are brought into the cell via these pathways that manipulate this constant flow of stuff into the cell. And osmosis, the cell gets for free. No energy is required to move stuff along its natural gradient (from higher to low concentration).

The fact that the natural flow of energy, water, ions, can be harnessed is what makes life possible.

These little wheels are everywhere. They are in our cells and in the sun; some are larger than us, like spinning galaxies and burning stars and tornadoes and the water cycle, and some are smaller than us, like outward rectifying K channels in the guard cells of stomata, or pinwheels.

This means that entropy, the same thing that is wicking away the energy of the universe, is the driving force behind life on this planet, and the universe as a whole. It is the rough sea that keeps the universe alive, and as it calms, so too will the universe die.

This is what we mean when we say that death is a part of life.



Adventure is out there.