Category Archives: Physics

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

Physicist: 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 says that if you take the universe and everything in … Continue reading

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

Q: Are some colors of light impossible? Can any color of light be made?

Physicist: Just so we can talk about this using physics rather than poetry, for the sake of this article “color” really means “frequency”.  Light frequency is a bit more objective than color and includes things we can’t see (like ultraviolet). … Continue reading

Posted in -- By the Physicist, Physics, Quantum Theory, Relativity | 9 Comments

Proxima B!

Physicist: Good news!  There’s an Earth-sized planet in the habitable zone of Proxima Centauri, a star so named because it’s the closest star to Earth and it’s in the constellation Centarus.  This isn’t a question anyone asked, but I thought … Continue reading

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

Q: Is there anything unique about our solar system?

Physicist: Maybe. As far as stars go, ours is a dull as dishwater, middle of the road, dime a dozen, main sequence star.  You can’t spit in space without hitting a Sun-like star.  So this question is really about the … Continue reading

Posted in -- By the Physicist, Astronomy, Philosophical | 5 Comments

Q: What is dark energy?

Physicist: The universe is expanding and the rate of that expansion is accelerating.  If the universe were full of only matter (both regular and dark) and energy, then we’d expect that the expansion would be slowing.  Dark energy is the … Continue reading

Posted in -- By the Physicist, Astronomy, Physics, Relativity | 28 Comments

Q: What are “actual pictures” of atoms actually pictures of?

Physicist: Actual pictures of atoms aren’t actually pictures at all. There are a few good rules of thumb in physics.  Among the best is: light acts like you’d expect on scales well above its wavelength and acts weird on scales … Continue reading

Posted in -- By the Physicist, Physics, Quantum Theory | 12 Comments