Category Archives: Probability

Q: Why don’t “cheats” ever work on the uncertainty principle? What’s uncertain in the uncertainty principle?

Physicist: The Uncertainty Principle is often stated as “the position and momentum of a particle cannot be simultaneously and perfectly measured”.  Mathematically, it’s written as , which means that the product of the uncertainties in the position, x, and momentum, … Continue reading

Posted in -- By the Physicist, Physics, Probability, Quantum Theory | 2 Comments

Q: In an infinite universe, does everything that’s possible have to happen somewhere?

The original question was: Lets say that we determine that an event is physically possible. So that means the probability of that event is greater than zero. Right? So my question is this. Is there any sense in saying that … Continue reading

Posted in -- By the Physicist, Philosophical, Probability | 6 Comments

Q: What is the probability of an outcome after it’s already happened?

Physicist: There are a lot of subtleties to this.  Reading the question, your gut reaction should be “Duh, it’s 100%!  Wait, is this really a question?”. And yet, there are many times in which you may find yourself estimating probabilities … Continue reading

Posted in -- By the Physicist, Philosophical, Probability, Quantum Theory | 7 Comments

Q: How do you answer a question scientifically?

Mathematician: Suppose you’re interested in answering a simple question: how effective is aspirin at relieving headaches? If you want to have conviction in the answer, you’ll need to think surprisingly carefully about how you approach this question. A first idea … Continue reading

Posted in -- By the Mathematician, Math, Philosophical, Probability | 1 Comment

Q: Is it likely that there are atoms in my body that have traveled from the other side of the planet, solar system, galaxy, or universe?

Physicist: Not just likely, but essentially guaranteed! Technically, every atom in your body has been swirling all around the galaxy for billions of years (although it’s mostly stayed in the same place for the last 5 billion or so).  So … Continue reading

Posted in -- By the Physicist, Astronomy, Physics, Probability | 6 Comments

Q: How is radiometric dating reliable? Why is it that one random thing is unpredictable, but many random things together are predictable?

The original question was: Suppose there is a set of variables whose individual values are probably different, and may be anything larger than zero. Can their sum be predicted? If so, is the margin for error less than infinity? This … Continue reading

Posted in -- By the Physicist, Combinatorics, Math, Particle Physics, Probability | 3 Comments