# How to determine the outcome of an event in the Quantum world?

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• In quantum physics, the wavefunction collapses to a definite outcome at random. You can calculate the probability of an outcome, but that is the best you can do.

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• Use quantum theory.

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• Throw some dice.

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• Wait until it has been Untangled • Login to reply the answers
• Using statistics.

The analysis of the quantum world is one of probabilities.

In classical physics, we use "averages" and apply them to large amounts (mass or quantities) of objects.

For a crude analogy: given 10 grams of Radon-222 today, you will find that, after 3.8215 days, you will only have 5 grams left. And that value is precise enough that you can safely bet your paycheck on it (just give yourself a "plus-or-minus 100 milligrams" just to be sure)

However, if you are given a single atom of Rn-222, when will it decay?

In the next minute? Six years from now? You can't tell. All you can say is:

There is a 50% probability that it will decay within 3.8215 days (3 d 19 h 42 m 58 s) and 50% probability that it will take longer.

This is an example of "we know what will happen, we just don't know when".

If you are trying to ascertain the position of an electron (for example) at a very precise moment, you cannot really tell where it is. All you can do is use a probable distribution. Graphically, the electron's position would look like a probability cloud (darker around the most probable position, lighter as you move away, but never down to exactly 0%).

Some go as far as stating that the electron itself is spread out over that volume (interpreting the electron as not being a solid particle).

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• Due to randomness, it's "wait and see".

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