Physical Sciences

Gravity is a Mystery (in words, no equations)

before the big bang. The future has a similar feel. The personal story ends for all reading this in ...

Blog Post - Doug Sweetser - Oct 29 2011 - 12:17pm

Self Replicating Robots- Safer For Galaxy (and Earth) Than Human Colonists- Is This Why ETs Didn't Colonize Earth?

century, you convert all the matter in the observable universe into humans within 18,000 years. (Here I say ...

Article - Robert Walker - Oct 29 2015 - 11:34am

No Simple Genetic Test To Separate Earth From Mars Life- Zubrin's Argument Examined

backbones. So to date, 70% of the archaea phyla have no cultivated "species" at all, and around 39% ...

Article - Robert Walker - Mar 11 2016 - 12:19pm

Puzzle: Which Tank Fills First? What Happens If You Increase The Flow Rate? Someone Tried- With A 3D Printer

Finally μ is the  dynamic viscosity All of those are constant (the pipes are all the same radius, and the ...

Article - Robert Walker - Aug 9 2017 - 11:48pm

The Probability Density Function: A Known Unknown

for all x>0. There exist more functional forms that are valid PDFs than stars in our universe, so ...

Article - Tommaso Dorigo - Mar 19 2025 - 11:44am

Is It True That An Asteroid Will Strike Earth On [Insert Date Here]?- Truth Behind Asteroid Scare Stories

asteroid that will hit the Earth as we are hit by meter scale objects all the time.  You usually get these ...

Article - Robert Walker - Sep 22 2015 - 6:07pm

Physical Reality: Less Is More

that a total of four out of the seven base units are spurious. In SI, all that is needed to measure ...

Article - Johannes Koelman - Oct 26 2010 - 10:54am

Snarky Puzzle Answers 2

4.4 form the foundation of all concepts presented in this book I had found errors of omission in those ...

Blog Post - Doug Sweetser - May 25 2011 - 12:12pm

Top 10 Scientific Uses For Leftover Halloween Candy

efficiency of the shape of M&M’s. M&M’s are one of my all-time favorite candies. Their colorful, ...

Article - Kimberly Crandell - Oct 31 2017 - 1:22pm

Why Didn't ETs, Or Self Replicating Machines, Colonize Our Solar System Millions Of Years Ago?

everyone, all the trillions of ETs, in all those habitats, follow this directive? We may colonize our solar ...

Blog Post - Robert Walker - Jan 19 2014 - 11:06am