Why dont quantum effects materalize in our size scale?

Question

For example, an electron can occupy multiple places, until we look at it, then, as in the double slit expierment, it chooses just one.

Im open to the possibility that I misunderstand the Heisenberg Uncertianty Principal, lol.

Anyway, I would like to have all the atoms in this $100 bill be in both my pocket and my wifes pocket at the same time. Why isnt this possible?

(Well it is, but without my pants being in her pocket, smartass)

(Adding details, hope this dosent erase anything.)

Thats an interesting reply scarlet, and +1 for doing it so clearly. :-)

Side note : I hate how I cant 'banter' back and forth, and the answers turn in to one way conversations, when I would sometimes like to counter or add something and make it more of a discussion than a one way street.

Answer 1

I've often experienced the effect where money that was last observed in my wallet suddenly appears in my wife's wallet on the next observation, which I can only assume is due to some form of quantum tunnelling. ;-)

Anyway, for a SERIOUS answer, if the $100 bill is in your pocket, any individual particle in it has a small but not completely negligible probability of being in your wife's pocket on the next observation (actually, it probably IS completely negligible, but let's be generous and assume it isn't). However, there are likely to be something on the order of 10^22 or more particles in the bill. The probability that even 0.00001% of them will be in your wife's pocket at the same time is the original small probability to the power of 10^15 (i.e. 1000000000000000). Even if the probability for a single particle was 99%, to have 0.00001% of the bill in your wife's pocket would have a probability that in percentage terms would start with 4364805402448 (over 4.3 trillion) zeroes after the decimal point. So the chance of an observable change of position happening to the bill by purely quantum effects is completely negligible.

Answer 2

You certainly have to be careful about your interpretation of quantum mechanics and it may well not be true to say an electron "can occupy multiple places". And you have to be very careful about terms like "until we look at it" - quantum effects are manifest without anyone looking at a system.

The reason we cannot see quantum effects at our level is that Planck's constant is so very small. The underlying relationship that is important is the anticommutation of conjugate variables - a mouthful but what it means is that, for example, if you take position x and momentum p then:

px - xp >= h/2pi

Now classically you would expect px - xp = 0. This relation applies to absolutely everything in the universe - but h is 6.6 x 10^-34 Js - it is effectively zero for something the size of a dollar bill. So you will never observe a quantum effect on that scale.

Answer 3

Basically because the Heisenberg uncertainty principle, which arises because of the dual nature of matter as a particle and a wave, allows precision of macroscopic measurements. Planck's constant is small with respect to macroscopic objects, so you can make accurate measurements and quantum effects aren't visible.

Answer 4

because they are being observed!!!

aha yea I have no idea