Monthly Archives: April 2014

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: Why are many galaxies, our solar system, and Saturn’s rings all flat?

Physicist: This may be the shortest answer yet: “accretion“. Accretion is the process of matter gravitationally collapsing from a cloud of dust or gas or (usually) both.  Before thinking about what a big cloud of gas does when it runs … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 13 Comments

Q: How do you define the derivatives of the Heaviside, Sign, Absolute Value, and Delta functions? How do they relate to one another?

Physicist: These are four standard reference functions.  In the same way that there are named mathematical constants, like π or e, there are named mathematical functions.  These are among the more famous (after the spotlight hogging trig functions). The absolute value … Continue reading

Posted in -- By the Physicist, Equations, Math | 9 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 | 23 Comments

Q: Is it possible to have a completely original thought?

Physicist: Nope!  At least, not for the last 27 years. The last truly, verifiably original thought was had by Kjersti Skramstad of Oslo, in October of 1987.  She reported her insight immediately, as all original thinkers do, and since then there’s been … Continue reading

Posted in -- By the Physicist, April Fools | 26 Comments