I thought it might be fun to start a thread of interesting ways to describe the wonders of the universe in enjoyable and digestible ways. So let me begin with a few examples that I believe are true and a hope this thread doesn’t die on it’s ass.
Take a glass tumbler and dip it in the sea. Pour it back in and go home. Several years later, perhaps on the opposite side of the world, you take another glass and dip it into a sea. You’ll almost certainly have scooped up a few atoms that were in your first glass.
If you tried to do a scale model of the universe with the sun reduced to the size of an atom, the edge of the known universe would be 600,000km away.
Counter to popular opinion there are actually far more stars in the universe than there are grains of sand on the Earth - there are estimated to be 70 thousand million, million, million stars in the observable universe. That’s a lot. But you will find the same number of molecules in just ten drops of water.
^
From Ripley’s I think. It also mentioned that basically everyone several years after Christ’s death would have drank some of the water molecules used to baptize him.
From the net, I get the volume of water on the earth at 1.37 billion cubic kilometers, each of which is 10^15 milliliters, or 1.37 x 10^24 ml.
A cup is about 270 ml, so that’s 5.07 x 10^22 cups of water in the ocean.
From this page, we get 7.5 x 10^24 molecules in a cup.
Assuming even mixing–which seems reasonable after years–that means you can actually expect about 100 molecules (or 300 atoms) to be in common between the two cups.
This works on the coincidence that the number of cups in the ocean is comparable to the number of molecules in a cup; it’s similar to the “ceasar’s last breath” thing – the number of molecules in a lungful of air is pretty close to the number of lungfuls of air in the atmosphere. Hence…on average you breathe in a molecule or two from ceasar’s last breath each time you breathe. In the water case, the “coincidence” is easy to arrange since we get to pick the container size, and a cup is just about right.
A McDonald’s hamburger has pieces from however many hundreds of cows. If you stop and think about it, each one of those cows could have lived if you’d only taken that tiny portion of muscle from their bodies.
There is nothing remotely like even mixing among all the world’s waters! Even bodies directly connected to each other through narrow channels–like the Mediterranean and the North Atlantic–can have measurably different makeup. Hell, different-temperature layers right atop one another don’t have even mixing.
Fair enough, but that just means your time scale might have to be longer (or shorter, since the “top layer” would contain much less water), or your samples closer together geographically. I think the interesting “fact” here was supposed to be the way the math worked out, not a hydrodynamics course. I’m sure the atmospheric one doesn’t work out literally, either, since the atmosphere is chemically active.
You will often see arguments for Creationism or Intelligent Design saying that something with odds of only one in 10^50 is so unlikely to happen, that it’s fair to treat it as impossible. After all, the age of the universe is only about 410^15 seconds, so even if you had a trillion processes each producing a trillion results per second since the beginning of the universe, you would have only 410^39 results.
But if you thoroughly shuffle a normal deck of 52 cards and then deal them out one by one, you just beat odds of one in 8*10^67 that you would get that exact sequence.
I understand, but I prefer actual facts to “facts.”
You presented the atmospheric one as an “on average” incidence; even as a pure math exercise, this is a very different kind of statement–much easier to fulfill–than the OP’s “almost certainly will.”
The point of this is not that there would actually be actual water molecules from the first glass in the second. The point is to illustrate the size of a water molecule and the vast number of them in a glass of water, so many that there are more molecules of water in the glass than there are glasses of water in all of the oceans combined.
