1. Mar 31, 2016

### Eidetiken

There really should be a board where real physicist can answer questions from ignorant SciFi writers, but I couldn't find one. So here goes.

Question 1: I asked author Greg Bear and a local community college physics instructor this question and I'm wondering if people on here will have the same debate or a definitive answer:

While surfing the net I came across a page on tunneling that basically says: Say you are 16 years old and you want a nice new Porsche, but you can't afford it on your weekly allowance. Let's say your allowance is a crisp new $50 bill each week. You don't have the money but in quantum mechanics you could, by tunneling your money. Alright my question is: Will each$50 bill you tunnel be exactly the same, as in serial numbers, dates, and so on, or will each bill be different because they are coming from different places and times?

2. Mar 31, 2016

### Staff: Mentor

3. Mar 31, 2016

### Eidetiken

We're assuming you can. This is fiction, not fact. People can't time travel or teleport either, but people write books about it.

4. Mar 31, 2016

### Eidetiken

You can think of it as a thought experiment like Schrodingers Cat, kind of smeared out across time and space, in a superposition of two states, alive and dead, at the same time. Although, if Schrodingers Cat was capable of acting like a quantum particle, the cat might just tunnel out of the box. Hmm, I wonder what would happen if Schrodinger opens his box, the psi function collapses, and he finds the cat gone?

5. Mar 31, 2016

### phinds

I think since the question you are asking is based on magic, not science, you can make up whatever answer suits you.

6. Mar 31, 2016

### Eidetiken

Yea, I tried to base it on magic, but a physics instructor read it and told me the bills would all be different, because they are coming from different places. So I wrote Greg Bear, Bear wrote back that all the bills would be the same.

7. Mar 31, 2016

### newjerseyrunner

Your instructor is wrong, what are coming from different places? And what is tunneling and tunneling through what? Quantum mechanics has no duplication functionality, quantum tunneling just means that an elementary particle can jump from one position to another. Nothing macro could do that.

Superposition doesn't allow you to have two objects; it's one position existing in all possible positions until it's measured. Touching it, spending it, even shining a light on your dollar bill would cause an interaction that collapses superposition.

Is this for a story? You could just copy the object, record the state of all atoms in the object, then create those atoms in a new location. In Star Trek, the transporters and replicators used the same technology, the only difference was that the replicator stored the buffer so that it could also be recreated later.

8. Mar 31, 2016

### Eidetiken

He wrote it on the board with a typical bowl and marble to show it first, then he came up with this thought experiment. I'm the one that asked him if the bills he tunneled would have the same serial numbers. He got all flustered, thought about it, then said they would all be different.

Yes, this is for a story. I have a guy that dies from a heart attack and wakes up in the hospital. Strange things start happening, and he's wondering if he is actual alive or dead. He can view memories as if he is actually there. He can look at a photo of the beach and feel the hot sand under his feet, smell the kelp and feel the breeze on his skin. Later he discovers that his consciousness can inwardly travel through time and wind up in his younger body, at different stages in his life, but when he does this, the body he leaves behind dies, when his consciousness leaves. But he can view the body, he left in the future, lying on the ground. So I started thinking about this analogy my instructor used, if I have a character who's consciousness is acting all quantum, why not have him tunnel his money, because he's obviously dead and in some in some kind of quantum world?

And yes, during one of these bizarre visions, he imagines Schrodinger actually conducting his thought experiment, he imagines Schrodinger's contraption inside of steamer box, with an expanded metal partition isolating a tabby cat from a vial of sand with an isotope inside, a geiger counter, a vial of prussic acid, and a hammer. He sees all this so clearly that he feels sorry for the cat. When he reaches and takes the cat from the box, and the cat actually winds up in the hospital with him. He knows he's not in Kansas anymore. Meanwhile, I've got Schrodinger actually conducting his thought experiment, and when he opens the box, he finds his cat gone. This cat likes to torment Schrodinger by popping in and out for a visit once in a while.

9. Mar 31, 2016

### newjerseyrunner

I see two possibilities: 1) Your instructor doesn't know the first thing about quantum mechanics, or 2) You understood him incorrectly.

I don't follow any part of what this guy said and nothing about it seems rooted in quantum mechanics.

Also, if you remove Schrodinger's Cat, it's no longer the same experiment. The point of the thought experiment was to show how something can thought of as being in two states simultaneously (that's true, but only part of it.) The second part of what the experiment is for is to illustrate that the second you measure, you get a definite answer that was one of the original possibilities. You're introducing a third possibility.

10. Mar 31, 2016

### Eidetiken

Yea, I introduced the third possibility. I had John G. Cramer the next semester, he made things a little more clear.

11. Mar 31, 2016