Yearly Archives: 2011

Q: How does the expansion of space affect the things that inhabit that space? Are atoms, people, stars, and everything else getting bigger too?

Physicist: Way back in the day Edwin Hubble (of telescope fame) noticed that the farther away a galaxy is, the faster it’s moving away from us.  From this he figured out that the universe is expanding, but in a very … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 31 Comments

Q: What would Earth be like if it didn’t turn?

Physicist: The side of the Earth facing the sun would quickly become hotter than boiling water, and the side facing away would be cold enough for the atmosphere to freeze solid (condense into nitrogen and oxygen ice).  So all of … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 21 Comments

Q: According to the Many Worlds Interpretation, every event creates new universes. Where does the energy and matter for the new universes come from?

Physicist: There is no new energy or matter (or even new universes), it’s just that how it’s distributed depends on who’s asking, and in what “world” they’re doing the asking.  The important thing is: the universe doesn’t split or spawn … Continue reading

Posted in -- By the Physicist, Physics, Quantum Theory | 44 Comments

Q: Can wind chill make things “feel” colder than absolute zero?

The original question was: Is it possible for something to “feel” colder than absolute zero?  If the forecast called for 1K (1 Kelvin) with 20mph gusts of wind, would the wind chill be below 0K? Physicist: This is a beautiful … Continue reading

Posted in -- By the Physicist, Physics | 10 Comments

Q: What is “spin” in particle physics? Why is it different from just ordinary rotation?

Physicist: “Spin” or sometimes “nuclear spin” or “intrinsic spin” is the quantum version of angular momentum.  Unlike regular angular momentum, spin has nothing to do with actual spinning. Normally angular momentum takes the form of an object’s tendency to continue … Continue reading

Posted in -- By the Physicist, Equations, Math, Particle Physics, Physics, Quantum Theory | 77 Comments

Q: What is Bayes’ rule and how do I use it to improve my life?

Mathematician: Bayes’ theorem in one of the most practically useful equations coming from the field of probability. If you take its implications to heart it will make you better at figuring out the truth in a variety of situations. What … Continue reading

Posted in -- By the Mathematician, Equations, Math, Probability | 8 Comments