Dedwarmo

Arthur Benjamin: Lightning calculation and other “Mathemagic”

In this video Arthur Benjamin calculates squares of 2, 3, and 4 digit numbers faster than you can do it on a calculator. I know. I tried to keep up while watching the video. Audience members give him their birthdate and he tells them what day [...]

Image: Wikimedia

Say the name: Rhombicosidodecahedron
Read the article
See the rotating model

Marvin Minsky has written an article he calls, “Communicating with Alien Intelligence.” He does not address the problem of how to differentiate between random gibberish and a message from an alien intelligence. He skips ahead to a hypothetical meeting of humans and aliens and asks whether or not they would be able to [...]

Because I am fascinated by large numbers, I present here a paraphrased version of the story of the rice on the chessboard.
A man who lived in a wealthy kingdom had performed a great deed. When the King learned of this he decided to reward the man and asked him what he would like as [...]

I’m sure you’ve seen this before, but I liked it so much I thought I’d pass it on:
1,000 (thousand) seconds = 17 minutes ago
1,000,000 (million) seconds ago = December 7, 2008
1,000,000,000 (billion) seconds ago = 1976
1,000,000,000,000 (trillion) = 29,702 B.C.
Feel free to check my numbers.
86,400 seconds = 1 day
31,536,000 seconds = 1 year

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Save the Bryant Park Project
SaveBPP.org

Scanline VFX has created some amazing computer generated water effects with their proprietary Flowline fluid simulation software. Their website has some great videos demonstrating what they have done.
You can create similar effects with the free open-source software Blender. Of all the physical phenomena you can simulate with Blender, fluid dynamics is the easiest.
Here [...]

A Möbius strip is a mathematical surface with only one side and one boundary component, or what you might call an edge. If you put a half-twist in a rectangular piece of paper and join the ends the the result is like a Möbius strip.

As far as I can tell, not being an astronomer, the only way to measure the distance of a star using geometry is by measuring stellar parallax and angular diameter. The problem with angular diameter is that not all stars are the same diameter. A more distant, larger star could have the same [...]