Category Archives: Probability

Q: When “drawing straws” is it better to be first or last?

Physicist: As long as the person who cut the straws: 1) takes the last remaining straw and 2) has a decent poker face (or doesn’t know which is which), then it’s completely fair.  If they have a bad poker face, … Continue reading

Posted in -- By the Physicist, Math, Probability | 7 Comments

Q: If a long hot streak is less likely than a short hot streak, then doesn’t that mean that the chance of success drops the more successes there are?

One of the original questions was:  I understand “gambler’s fallacy” where it is mistaken to assume that if something happens more frequently during a period then it will be less frequently in the future.  Example:  If I flip a coin … Continue reading

Posted in -- By the Physicist, Math, Probability | 12 Comments

Q: If the number of ancestors you have doubles with each generation going back, you quickly get to a number bigger than the population of Earth. Does that mean we’re all a little inbred?

Physicist: In a word: yes.  But it’s not a problem in large populations. The original questioner pointed out that in the age of Charlemagne (more or less when everybody’s 40-greats grandfolk were living) the world population was between 200 and … Continue reading

Posted in -- By the Physicist, Biology, Evolution, Probability | 12 Comments

Q: If you flip a coin forever, are you guaranteed to eventually flip an equal number of heads and tails?

The original question was: Lets say we have a fair coin that is flipped a hundred times and at the end of the trial there have been 40 tails and 60 heads. At this time there have been 20 more heads than … Continue reading

Posted in -- By the Physicist, Math, Probability | 39 Comments

Q: Are some number patterns more or less likely? Are some betting schemes better than others?

Physicist: First, don’t gamble unless you can be sure you won’t get caught cheating or you enjoy losing money. Games of chance come in two flavors: “completely random” and “not quite completely random”.  It’s not always obvious which is which, … Continue reading

Posted in -- By the Physicist, Combinatorics, Entropy/Information, Math, Probability | 10 Comments

Q: What are “delayed choice experiments”? Can “wave function collapse” be used to send information?

Physicist: There are a lot of big claims made about entanglement, but there are two carved-in-stone facts that help cut through some of the more grandiose claims.  First, (maximally) entangled states always act exactly like a perfectly random state, until … Continue reading

Posted in -- By the Physicist, Entropy/Information, Experiments, Philosophical, Physics, Probability, Quantum Theory, Skepticism | 6 Comments