/sci/ - Science & Math

Think of that poor first observer (whether it be a conscious mind or a "system" of some other sort) to develop in the universe's superposition of states. With its very first measurement, it would be all but certain to observe a universe in which IT DID NOT EXIST.

http://en.wikipedia.org/wiki/Two_envelopes_problem

Great mindfuck question. If you're unfamiliar with it, try figuring out the flaw in the reasoning yourself. Here's the gist of it:

You are given two indistinguishable envelopes, each of which contains a positive sum of money. One envelope contains twice as much as the other. You may pick one envelope and keep whatever amount it contains. You pick one envelope at random but before you open it you are offered the possibility to take the other envelope instead.

At this point, you think:
1. This envelope contains some amount of money, X.
2. The amount in the other envelope is either 2X (with a 50% chance) or X/2 (with a 50% chance).
3. So the expected value of the other envelope is (2X)(1/2) + (X/2)(1/2) = 5X/4. This is greater than X, so you switch to the other envelope.
4. Using the same reasoning, you immediately switch back.
5. And on and on forever.

Good one, eh? Yes I know it's all there in the wikipedia page, but I just ran across this for the first time and thought /sci/ might like it.

If the arrow of time moved in a circle, we could look forward to the present moment, in which we will be happily contemplating our own future present. Or else we might end up dreading our own present dread. Myself, I think I'd go insane.

You are now aware that if you assume nothing about possible bias of a coin, and you flip it once and it comes up heads, the odds that the next TWO flips BOTH come up heads are (2/3)*(3/4) = 1/2.

ITT: math facts that blow your mind. I'll start.

It is unknown whether pi + e is rational or irrational.

>Gabrielle Giffords' face when she reads about quantum immortality

(not literally)

>>2819001
DUDE DON'T SAY SHIT LIKE THAT WHEN I'M HIGH

You are now aware that if we took positive numbers and decided to call them negative, and took the negative numbers and decided to call them positive, all of math would work just like it does now and no one would even notice the change. On some deeper level, 1 and -1 are actually the SAME NUMBER, which leads to the absurdity of 1 = -1. Therefore 0 is the only number that can truly be said to exist, since it is the only one that is equal to its metaphysical mirror image.

>One might say that the appearance of tumors in the body is a manifestation of the inner Metazoan 1.0 in all of us.

Simple, just assume it does not. Then

Is dissociative identity disorder real? This guy I know says it is, but I keep telling them she only thinks that because I tell others to believe me. Also how many people are on earth? About 80 trillion, right?

You're driving along and round a curve, seeing a red light ahead. Not knowing how long it's been red, what deceleration strategy should you emply to minimize your expected travel time (to some destination miles past the light)?

Answer: IT DOESN'T MATTER (as long as you don't stop before you get to the light).

Is /sci/'s mind blown? Because my mind is blown.