Think about all the decisions you make in a day. I’m not talking about the big decisions, like “should I join the Army?” or “should I get married?”. I’m thinking about the hundreds or thousands of little decisions you make in a day.
For example, on a weekday morning my better half will wake up and go to the bathroom to get ready. She will choose between this lipstick or that lipstick, this eye shadow or that eye shadow, then choose this dress or that dress, these shoes or those shoes, and this bracelet or that bracelet. She will then go downstairs and choose between yogurt and a banana for breakfast. She will then choose whether to drive the white Jeep or the green Jeep to work. She’ll then have to decide if she wants to take Wilkinson Boulevard or I-85 to get to the office, and whether to listen to “The Bob and Sheri Show” or something else along the way. She will decide whether to try to make a traffic light or if she should stop safely. A few minutes later, she will decide whether to change lanes, or wait for a truck to pass first. She’ll then have to decide whether to park in this space or that space. Once inside the office, she’ll have to decide whether to check her email or voicemail first, whether to return this call or that call first, then decide whether to process this invoice or that one. She’ll make a hundred other decisions before lunchtime, where she will decide whether to pick something up or open a can of soup she’s brought from home.
The reason I mention all this is because I had a thought yesterday.
If, as some scientists claim, the universe is infinite, then there must be another earth almost exactly like ours our there. I’ll grant you that the likelihood of there being a planet almost exactly like ours is low… but if we’re dealing with infinity, then the odds cannot be zero. And if there is more than one earth, then it’s possible that there are an infinite number of earths. And if there are an infinite number of earths, there must be an infinite number of Lisa Wilsons living on those earths.
It’s not predetermined that those other Lisa Wilsons would make the same decisions as my Lisa Wilson; indeed, it’s almost a cliche for documentaries about modern physics to talk about how there’s another earth somewhere out there where Napoleon won the Battle of Waterloo and yet another where Elvis is still alive.
So… let’s say that Lisa Wilson makes 300 decisions a day. In the interest of simplicity, let’s say that those are binary decisions (yes or no, this or that, etc.). Those 300 different decisions per day then become 90,000 possible combinations. That’s 32,850,000 combinations per year, and if we assume that Lisa lives to be 75 years old that’s 2,299,500,000 possible combinations in her lifetime (I cheated a bit and didn’t count the first five years of her life). Multiply that by 6 billion people living on the planet at the moment and you get 1.3797 × 1019.
That’s over a quintillion possible outcomes that, according to infinity, must exist on other possible earths. Yet, in a cruel twist of Fermi’s Paradox, we see absolutely no evidence of any other earths anywhere. How could there be a quintillion of anything, and us not be able to perceive it? I mean, I get that the Universe is large (infinite, even!) and I suppose that a quintillion earths spread out over an infinite space leads to large spaces between those earths. But still… you’d think that we’d be able to detect one of them by now, no?
Ah… the mysteries of the Universe. Discuss!