Category Archives: Particle Physics

Q: Does anti-matter really move backward through time?

Physicist: The very short answer is: yes, but not in time-traveler-kind-of-way. There is a “symmetry” in physics implied by our most fundamental understanding of physical law, and is never violated by any known process, that’s called the “CPT symmetry“.  It … Continue reading

Posted in -- By the Physicist, Particle Physics, Physics, Skepticism | 3 Comments

Q: How does Earth’s magnetic field protect us?

Physicist: High energy charged particles rain in on the Earth from all directions, most of them produced by the Sun.  If it weren’t for the Earth’s magnetic field we would be subject to bursts of radiation on the ground that … Continue reading

Posted in -- By the Physicist, Astronomy, Particle Physics, Physics | 8 Comments

Q: What is radioactivity and why is it sometimes dangerous?

Physicist: Here’s every particle you’ve ever interacted with: protons, neutrons, electrons, and photons*.  Dangerous radiation is nothing more mysterious than one of those particles moving crazy fast. The nucleus of some kinds of atoms are unstable and will, given enough … Continue reading

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

Q: Why does carbon dating detect when things were alive? How are the atoms in living things any different from the atoms in dead things?

Physicist: As far as carbon dating is concerned, the difference between living things and dead things is that living things eat and breathe and dead things are busy with other stuff, like sitting perfectly still.  Eating and breathing is how … Continue reading

Posted in -- By the Physicist, Biology, Particle Physics, Physics | 1 Comment

Q: Why does it take thousands of years for light to escape the Sun?

Physicist: The original statement is often something like, “It takes tens of thousands of years for a photon to get from the core to the surface of the Sun, but only eight minutes to get from the Sun to the … Continue reading

Posted in -- By the Physicist, Math, Particle Physics, Physics, Probability | 8 Comments

Q: What are quasi-particles? Why do phonons and photons have such similar names?

Physicist: Prefixes like “quasi-“, “psuedo-“, and sometimes “meta-” are basically used to mean “sorta like… but different… you know?”.  Quasiparticles behave like particles in a few fairly important ways, but aren’t actual particles at all.  The most important way, and … Continue reading

Posted in -- By the Physicist, Particle Physics, Physics, Quantum Theory | 4 Comments