The May 29 news article “Schrödinger’s imaginary cat can now be alive, dead and in two places at once” quoted a scientist as saying, “You can’t understand it using common sense. We can’t either.” Scientists say that because most accept the particle picture of nature promulgated by physicist Richard Feynman. Of course, the idea that a cat can be both alive and dead is, as Schrödinger himself said, “ridiculous.” But there is another theory, espoused by Feynman’s rival Julian Schwinger, that makes perfect sense. It is called quantum field theory, and it describes a world made of fields. My book, “Fields of Color,” shows how this oft-neglected theory resolves the paradoxes of relativity and quantum
Why is it said that light does not need a medium through which to travel? originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights. Answer by Brian Bi, who majored in physics, on Quora: We know that light doesn’t need a medium through which to travel because the speed of light is experimentally constant: independent of the movement of the source or detector or the direction in which it travels. Light contrasts with sound, which travels through the air (or some other material medium). If you’re stationary with respect to the air, then the speed of sound is the same in all directions. But if you’re moving with respect to
There are four fundamental forces of nature: gravity, electromagnetism, the weak interaction, and the strong. Glenn Randall, a physicist at Arizona State University, is currently working on a fascinating new experiment called DarkLight that could confirm this game-changing physics discovery. Randall walked Popular Mechanics through what this new force could be, why it could help us understand dark matter, and how DarkLight might prove it exists.
One of the most intriguing speculative arguments in physics and computer science isn't really about physics or computer science at all. It's about the brain - or more precisely, about consciousness - and it's been going on for decades. Its central question: Is the brain fundamentally like a computer? The side that says no relies on some seriously outlandish thinking. On the more conservative side, there are researchers like Scott Aaronson, a respected theoretical computer scientist at MIT. His view, which is more widely accepted, is that because the brain exists inside the universe, and because computers can simulate the entire universe given enough power, your entire brain can be simulated in