Category Archives: Physics

Q: What exactly is the vacuum catastrophe and what effects does this have upon our understanding of the universe?

Physicist: The vacuum catastrophe is sometimes cited as the biggest disagreement between theory and experiment ever.  They disagree by a factor of at least 10107. According to quantum field theory the energy of empty space can’t quite be zero.  In … Continue reading

Posted in -- By the Physicist, Astronomy, Particle Physics, Physics, Quantum Theory | 22 Comments

Q: What is a “measurement” in quantum mechanics?

Physicist: Any interaction of any kind that conveys information is a form of detection. This question crops up frequently in conjunction with the “Copenhagen interpretation”. The Copenhagen interpretation of quantum mechanics (which comes in a couple different flavors) is generally … Continue reading

Posted in -- By the Physicist, Entropy/Information, Physics, Quantum Theory | 28 Comments

Q: How close is Jupiter to being a star? What would happen to us if it were?

The original question was: I have heard Jupiter referred to as a failed star.  That if the cosmic chaos of the early solar system had worked out a little different, and Jupiter had gotten a bit more mass, it might … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 135 Comments

Q: Is it possible to destroy a black hole?

The original question was: Aside from Hawking radiation, is it possible to destroy a black hole? Specifically, could you rotate a black hole fast enough that it was flung apart? Also, assuming that m is the mass necessary for a … Continue reading

Posted in -- By the Physicist, Physics | 48 Comments

Q: Why does the Earth orbit the Sun?

The original question was: What exactly causes the Earth’s rotation and revolution?  Does this occur due to centripetal force and the lack of friction to stop the Earth from spinning? IE- Newton’s First Law? If so, where did this centripetal … Continue reading

Posted in -- By the Physicist, Astronomy, Equations, Physics | 63 Comments

Q: If you suddenly replaced all the water drops in a rainbow with same-sized spheres of polished diamond, what would happen to the rainbow? How do you calculate the size of a rainbow?

Physicist: A normal rainbow is created when light enters a water droplet, bounces once off of the far side, and comes back out. Diamond “droplets” however don’t make rainbows.  In order to get a rainbow that exists, and isn’t in … Continue reading

Posted in -- By the Physicist, Equations, Geometry, Physics | 4 Comments