Category Archives: — By the Physicist

Q: If there are 10 dimensions, then why don’t we notice them?

Physicist: A “dimension” is a direction.  So, we’re in “3 dimensions” because there are only 3 directions, and every other direction is just a combination of those 3 (and their negatives).  For example, by telling someone how far north, east, … Continue reading

Posted in -- By the Physicist, Physics | 21 Comments

Q: Will the world end tomorrow?

Physicist: Probably not.  Update to follow. Update (12/22/12): Nope.

Posted in -- By the Physicist, Skepticism | 5 Comments

Q: In an infinite universe, does everything that’s possible have to happen somewhere?

The original question was: Lets say that we determine that an event is physically possible. So that means the probability of that event is greater than zero. Right? So my question is this. Is there any sense in saying that … Continue reading

Posted in -- By the Physicist, Philosophical, Probability | 65 Comments

Q: Which of Earth’s life forms could survive on each planet of the Solar System?

Physicist: We can feel fairly certain that no life from Earth can survive on the surface of any of the other planets. Mercury is really inhospitable.  Although there’s some water ice in craters near it poles, there’s very little hope … Continue reading

Posted in -- By the Physicist, Astronomy, Biology | 12 Comments

Q: What are fractional dimensions? Can space have a fractional dimension?

Physicist: There are a couple of different contexts in which the word “dimension” comes up.  In the case of fractals the number of dimensions has to do (this is a little hand-wavy) with the way points in the fractal are … Continue reading

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

Q: Are shadows 2-dimensional? Are there any real examples of 2-dimensional things in the universe?

Physicist: If you think of a shadow as the lack of light created by an object blocking a light source, then shadows are 3-D.  After all, it’s dark everywhere behind an object, not just on the surface of another object. … Continue reading

Posted in -- By the Physicist, Physics | 26 Comments