Author Archives: The Physicist

Q: A flurry of blackhole questions!

Q: How much of the universe’s mass is currently in black holes? Blackholes fall into two basic categories: stellar mass blackholes which have a mass of 3 to 30 Suns (give or take), and super-massive blackholes which usually have masses of … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 11 Comments

Q: Why does going fast or being lower make time slow down?

Physicist: Back in the day, Galileo came up with the “Galilean Equivalence Principle” (GEP) which states that all the laws of physics work exactly the same, regardless of how fast you’re moving, or indeed whether or not you’re moving.  (Acceleration … Continue reading

Posted in -- By the Physicist, Physics, Relativity | 109 Comments

Q: What’s so special about the Gaussian distribution (i.e. the normal distribution / bell curve)??

Physicist: A big part of what makes physicists slothful and attractive is a theorem called the “central limit theorem”.  In a nutshell it says that, even if you can’t describe how a single random thing happens, a whole mess of … Continue reading

Posted in -- By the Mathematician, -- By the Physicist, Entropy/Information, Equations, Math, Probability, Quantum Theory | 11 Comments

Q: Is the universe infinitely old?

Physicist: Normally this question is only used to start fights. Some theories posit that the big bang was the beginning of everything, and that it doesn’t make sense to talk about anything earlier, while others say that it may be … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 4 Comments

Q: Have aliens ever visited Earth?

Physicist: No. Space is big.  The distances involved are ridiculous, the energies are ludicrous, the costs are somethingelseous.  The New Horizons probe (due to reach Pluto in 2015) is the fastest vehicle ever created.  At its top speed of 16.26 km/s … Continue reading

Posted in -- By the Mathematician, -- By the Physicist, Astronomy, Physics, Relativity | 45 Comments

Q: Why is the sky blue?

Physicist: The blue of the sky is sunlight that has been scattered by the air in a process called Rayleigh scattering.  The probability that a photon of frequency is scattered is proportional to .  So purple (the highest frequency we … Continue reading

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