Category Archives: Philosophical

Q: Before you open the box, isn’t Schrödinger’s cat alive or dead, not alive and dead?

The original question was: If I don’t open the lid of the bunker, the cat inside is either dead OR alive.  Why does Schrödinger say that the cat is both alive AND dead if I do not perform the act of … Continue reading

Posted in -- By the Physicist, Philosophical, Physics, Quantum Theory | 29 Comments

Q: How many times do you need to roll dice before you know they’re loaded?

Physicist: A nearly equivalent question might be “how can you prove freaking anything?”. In empirical science (science involving tests and whatnot) things are never “proven”.  Instead of asking “is this true?” or “can I prove this?” a scientist will often … Continue reading

Posted in -- By the Physicist, Experiments, Math, Philosophical, Skepticism | 5 Comments

Q: What does “E=mc2” mean?

Physicist: This famous equation is a little more subtle than it appears.  It does provide a relationship between energy and matter, but importantly it does not say that they’re equivalent. First, it’s worth considering what energy actually is.  Rather than … Continue reading

Posted in -- By the Physicist, Equations, Philosophical, Physics, Relativity | 25 Comments

Q: How do we know that atomic clocks are accurate?

Physicist: It turns out that there is no way, whatsoever, to look at a single clock and tell whether or not it’s accurate.  A good clock isn’t so much accurate as it consistent.  It takes two clocks to demonstrate consistency, … Continue reading

Posted in -- By the Physicist, Experiments, Logic, Philosophical, Physics | 12 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

Q: How do I encrypt/hide/protect my email?

Cryptographer: Lots of people have been asking “how do I encrypt my email” or “how can I hide from NSA surveillance”. It turns out that the answer to the first question is fairly straight forward, while the second is not, … Continue reading

Posted in -- Guest Author, Computer Science, Paranoia | 4 Comments