This came from a dream, I have cats, just changed the litters before bed, and I love the movie Hot Tub Time Machine.

In the dream, me and a bunch of friends discover that a cat litter box can send you to a parallel universe (it might have also possibly traveled through time a bit).

This presented an interesting problem. If you go to another parallel universe, how do you know, and also, how will you know if you got back to your original universe. And maybe you wanna find out about some other things about different parallel universes.

Let's say there are 5 friends, A, B, C, D, E. You are person A, the finder of the great discovery.

Tell your friends to order themselves in whatever order they like, with you at the head of the line. Taking an index card in landscape orientation, draw lines to make three rows. In the the middle row, make 5 columns and have each person write their names at the tops of the columns in the order they are in the line. Take a die, and roll it, and write your number under your name, and have each person do the same in order. People should write their own so that it is in their handwriting.

At the top of the card, write "Machine". Also circle your name to indicate that you were the one who decided to create this method.

Now, have everyone take a separate card and copy everything from the original card, except, write their name on the top of the card instead of "Machine." This will be their parallel universe passport. The numbers from the dice will be the identifying number for this universe. On the back of their card, on individual lines they would write the numbers of each universe they visit.

Going through the litter box machine to another dimension might reveal a set of interesting things:

• Would the randomness of the dice make it so each universe was different
• Would the order of the people be different or would they be random and based on the whim of the person in that universe
• Would the creator of the card be different
• If you set through the machine, would the you in the other dimension be there too, or would they swap places with you, or would it create a cascade of you's stepping through the portal through the multiverse so there would just be one you in each universe
• If that is true, then what would happen if you roll a die to see who goes through the portal.

I am assuming with all this that universes that you get to would be nearly identical to yours, but still randomness would happen with a dice roll that would create different ID numbers at the time before you enter the machine.

I wonder if the machine would take you to only a universe that is nearly identical to yours, but only different a second before you enter the machine. Perhaps the split would happen after you create the IDs ... so you might want to create the IDs as close to when you step through the portal as possible. A lot of universe splitting might happen over the course of an hour.

The dream didn't have any conclusions for any of this. I did come to one conclusion though. Parallel Universe Machine doesn't roll of the tongue the same way Time Machine Does. Just a lot of syllables there.