Easter, by the numbers

Jay Ryan from Classical Astronomy gives a good overview of why we celebrate Easter when we do.   You'll learn such intricacies as:

[...] every 19 years, the Moon's phases will recur on the same dates of the solar year.  This 19 year "luni-solar" cycle was the basis for the calendar used in Babylon. In the west, its discovery is attributed to the Greek philosopher Meton, who may have learned it from the Babylonians. The 19 year cycle was generally well known and understood in antiquity, and was apparently used by the Persian rulers of Babylon after the restoration of Israel.

Full article...

Now you see it...

From the project's page:

"We propose a method for removing marked dynamic objects from videos captured with a free-moving camera, so long as the objects occlude parts of the scene with a static background."

In other words, they can delete people or other moving objects from videos, even if the objects momentarily block other (even moving) objects in the background.   Have video evidence of your existence?  Too bad: you have been erased.  Demo:

Close enough

I ran across an interesting tidbit that I missed during my years in school.   Apparently 0.9̅ = 1.  (If you can't see the special character, the 0.9 is repeating, meaning 0.9999999...)  I initially didn't believe it either, since I, too, thought of this number as something approaching the limit of 1.    It turns out that you have to think harder about the nature of infinity in order to get your definitions right.   What helped me is this:  how small is the difference between 0.9̅ and 1?  It's infinitely small, or 0.

From Wikipedia:

"The equality 0.999... = 1 has long been accepted by mathematicians and is part of general mathematical education. Nonetheless, some students find it sufficiently counterintuitive that they question or reject it, commonly enough that the difficulty of convincing them of the validity of this identity has been the subject of several studies in mathematics education."

Link to article...

Also, the best part:

"Q: How many mathematicians does it take to screw in a lightbulb?"
"A: 0.999999...."

Q193: Proof of belief

"Faith is the essence of what we do: when we believe in something, we act on it."

— Nick Begich