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## happy tau day!

Happy WHAT, you may ask? Well, those who read this blog may recall me writing about pi day on 3/14. There were many geeks writing about pi on that day. And many of them linked to Vi Hart’s video telling us what is wrong with pi and how we really should use tau (twice pi […]

## happy pi day!

Today is pi day, 3/14. You know, pi, the irrational number, 3.141592654… We all learned the basic formulas for a circle involving pi in school: (circumference equals pi times diameter) (area = pi times the radius squared) OK, no more formulas. I promise. With today’s computers, the value of pi has been calculated to millions […]

## more on big AND small numbers

I wrote about big numbers, specifically Avogadro’s number. Here is a classic video showing the relative size of everything around us, big AND small, represented by these numbers.

## a REALLY big number — a mole

I wrote about what an incomprehensible number 1 trillion is. And it still IS incomprehensible to me when talking about it as a number of dollars. But there are bigger numbers, MUCH bigger numbers. For instance, there are 50-75 trillion cells in a single adult human. And there are about 20 times that many bacteria […]

## a trillion truly IS an astronomical number

In the last few years, there have been very large numbers thrown around when describing the US budget and deficit. These numbers are so large they are best expressed using scientific notation (you know, 1 trillion = 10¹²); they are almost incomprehensible. Some would say they are astronomical. So here goes. If you were able to […]