Shroedinger's Bag (3.5e Equipment)
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"Did you hear that?"
Spalding turned to Pel, pausing as the bard caught up with the rest of the party. They all sat down, resting from their long trek.
"It sounded like a 'meow'." Pel paused as the meowing resumed, nearby.
"I think it's coming from inside that bag you grabbed, Pelly," Ampere said, with her quiet lilting voice.
Pel reached over and untied the bag's cinch. He'd lifted it from a temple to Shelgoth, which had been a completely normal dungeon run until someone had said... 7a. Pel shuddered, but pushed the thought from his mind as he reached into the bag.
"Can't be a bag of holding, I can feel the insides." Pel's hand closed around something, and he pulled it out. And pulled it out. And pulled it out.
"Maybe it is magical, Pel. Why would there be a ten foot pole in there?" Ampere said, after Pel had extricated the wooden pole. He reached his hand back in, and closed around another object. His hand removed a Kings Sapphire.
"Holy Chakara, Pel! Gimme that!" Ampere said, taking the bag from the bard, who had determined that the stone was not faked.
"Is that what I think it is, Amps?" Hex asked, as she pulled out the object she had found. In her hand, hanging by its tail, was a cat.
"Is it dead?" Spalding asked, prodding the animal.
"I can't tell. Hold on, there's something on the bag." Pel reached over and took the bag. "Property of... Erwin Shroedinger?"
 Schrödinger’s Bag
This bag, which belonged to a wild mage named Erwin Schrödinger, was created while Mr. Schrödinger was attempting to disprove the very property that powers the bag. He wished to prove that items always exist in set states, and that it's impossible for something to exist 'In probability'. He invented the bag as something of a counter-example, but when the bag actually worked in the way that he had intended it not do, he grumbled and gave the bag to a fellow mage.
The bag passed through many hands, and currently appears wherever it's remembered. It seems to be indestructible, and if damaged, it will repair itself.
Schrödinger’s bag possesses the ability to summon objects that its user is thinking about. For example, if a user is hungry, they will find some food. Whether it is a bag lunch or a full banquet with a table and candles is dependent on the bag.
To use the bag, the user concentrates on an item. It cannot be something specific, like a Vorpal sword or a masterwork mace, but instead must be more of a category of items, like 'Food' or 'Arrows'. Then the user reaches into the bag, and feels around. While the character reaches around, the DM rolls a d20. The better the roll, the better the item withdrawn. However, in the end, the item withdrawn is the DM's call.
If the user does not concentrate on anything, and reaches into the bag, they will remove something completely random, although, if the DM chooses it, it may be something useful for the current situation.
All items taken from the bag will disappear one hour after they are removed, because creating permanent items would disrupt causality, and Schrödinger liked reality the way it was.
 The Cat
Schrödinger’s Bag is powered by a cat. Don't ask why, Schrödinger thought it was a good idea at the time. You can see the Note below to understand why maybe this bag is powered by a cat, and why there is a 50% chance to withdraw a dead cat and a 50% for an alive cat when you roll a 1.
If the DM rolls a 1 when using the bag, the player will withdraw a cat. There is a fifty percent chance the cat will be dead, a fifty percent chance it will be alive, and a one percent chance it will be both (For explanation, see the Note below).
If the cat is removed from the bag, the bag will become a normal cloth sack for an hour. After the hour has passed, the cat will vanish, no matter where it was placed or the condition it is in. The bag will begin to work normally after that.
Note about Schroedinger's Cat: Schrödinger was a scientist who proposed the equation of waves in quantum mechanics. with this equation, you can calculate the probability of a particle to be in some point in space. However, there are some phenomena that occurs in the microworld that can't be explained in the macroworld. One experiment to show some of this phenomena is called 'Schrödinger's Cat', and that's maybe why there is a cat relationed with the Schrödinger's Bag. There are several videos in YouTube that explains this experiment. The Schrödinger's Cat experiment is a thought experiment. That means that is an experiment that can't be done in practice, but it can be analyzed in theory. To explain it simply, the experiment consists on a cat trapped inside a box. The box has a radioactive substance in a recipient, and this substance has 50% chances to disintegrate and emit a particle (which can be analyzed with quantum mechanics if its isolated) in an hour. If a particle is emitted, a detector gets a signal and activates a mechanism that breaks a bottle with a deadly poison. You put all this with the cat inside the box and you don't know what happens inside of it until you open it after an hour. Quantum Mechanically, the cat has within this hour a superposition of states: the cat is 50% live and 50% dead at the same time, but that cannot happen because those are mutually exclusives: the cat is live or dead. That superposition of states can occur in quantum mechanics: for example, before measuring the spin of an electron, the electron is 50% spinning clockwise and 50% spinning anticlockwise. When we measure it the electron 'chooses' one of them (because when measuring we are altering the state of the electron) and that is the one that we 'see'.
Schrödinger’s bag can be used for storage like any bag, although to remove the item the character must concentrate like any other item.
 DM Notes
This item was originally introduced in the exact manner as above. Our DM was on a physics kick, and he has already created the sword of Planck's constant, which allowed the user to enlarge or shrink any object struck by the sword, down to Planck's constant.
The strangest item we ever pulled from the bag would have to have been a debit card, backed by the Template's Bank. Actually, there are probably stranger things, but it was high on the list.