Category Archives: — By the Physicist

Q: How did Lord Kelvin come up with the absolute temperature? I mean, how could he say surely that it was 273.15 C below zero?

Physicist: Lord Kelvin (and others of his ilk) noticed that when you hold the volume of an ideal gas constant you get a nice, linear relationship between pressure and temperature. By the by, an ideal gas is just a gas … Continue reading

Posted in -- By the Physicist, Physics | 14 Comments

Q: What do complex numbers really mean or represent?

Physicist: Nothing really. Complex numbers are very useful for streamlining a lot of different types of math, generalizing ideas, and “closing” the real numbers.  In quantum theory you’ll find that on the most fundamental level the universe seems to prefer … Continue reading

Posted in -- By the Mathematician, -- By the Physicist, Math, Philosophical | 14 Comments

Q: Is it odd that the universe’s constants are all so perfectly conducive to life?

Physicist: Maybe. When written down, most physical laws involve at least one physical constant.  For example, the “G” in gravitational force: , or the “h” in the energy of photons: , or the speed of light: “c”.  There are a … Continue reading

Posted in -- By the Physicist, Philosophical, Physics, Quantum Theory | 18 Comments

Q: How/when will the world end?

Physicist: To answer this question definitively would require the destruction of at least a couple dozen other worlds.  But failing that, guesswork: The little things (people): In the short term (less than several million years) the biggest threat the Earth … Continue reading

Posted in -- By the Physicist, Astronomy, Biology, Paranoia, Physics | 5 Comments

My bad: Have aliens ever visited Earth?

Physicist: In the post “Q: Have aliens ever visited Earth?” I said that the maximum velocity that can be obtained by a rocket using fusion is 11% of light speed.  Wrong! It turns out that (as a commenter had suggested) … Continue reading

Posted in -- By the Physicist, Mistake | 6 Comments

Q: How do Bell pairs (entangled particles) behave experimentally?

Physicist: When a photon with an unknown polarization hits a polarizer it has a 50% chance of being stopped and a 50% chance of going through.  However, once the photon has passed through a polarizer then its polarization is known … Continue reading

Posted in -- By the Physicist, Physics, Quantum Theory | 13 Comments