# Category: Science

Two articles about the Maya civilization:

Seeker article about LiDAR being used to reveal ancient structures on the Jungle ground: A network of 150km of prehistoric Autobahn ran through the Jungle, binding the Mayan Empire together.

“These causeways are 130 feet wide, up to 20 feet high and in some cases they extend as far as 25 miles,” Hansen said.

A causeway is a raised road across difficult, often wet or unstable ground. Because of the raised structure LiDAR can find these roads even today.

Unlearning Descriptive Statistics explains many things you should know about working with Numbers that your Statistics Class in University probably did not explain properly.

If they did, maybe Graphite would not hurt so much, with all the Averaging going on where it shouldn’t, and maybe Gill Tene would not have had to give talks like How NOT to measure latency (which is awesome, by the way and if you haven’t seen this talk, do it right now).

From the Intro of Unlearning:

If you’ve ever used an arithmetic mean, a Pearson correlation or a standard deviation to describe a dataset, I’m writing this for you. Better numbers exist to summarize location, association and spread: numbers that are easier to interpret and that don’t act up with wonky data and outliers.

Statistics professors tend to gloss over basic descriptive statistics because they want to spend as much time as possible on margins of error and t-tests and regression. Fair enough, but the result is that it’s easier to find a machine learning expert than someone who can talk about numbers. Forget what you think you know about descriptives and let me give you a whirlwind tour of the real stuff.

Article in the FAZ (article in german): Two pupils attending a Gymnasium in Frankfurt got the measles. The vaccination records of 800 pupils are being checked. Youths without vaccination are being banned from attending school for safety reasons.

2016, 14 cases of measles have been registered in 2016, down from 70+ the year before. One girl died from complications (article in german), effectively killed by her parents denying her vaccination. Measles viruses can attack brain cells, and if the sickness progresses to that stage, it is always deadly.

Vaccination helps.

Why is our galaxy moving through space, and into which directions is everything else moving?

Scientists at the Hebrew University of Jerusalem have been mapping these forces, and found a very empty region in space that seems to push a lot of galaxies away from it, as well as a (previously known) region thats attracting them.

The result looks like a billion light year magnet:

What causes these forces is as of now not well understood.

Original Paper in Nature Astronomy.

A crystal is a regular, repeating structure of matter in space. What if we made a regular, repeating structure in time instead?

Wilczek countered that a time crystal was more akin to a superconductor, in which electrons flow with no resistance, and in theory could do so forever without the need to add energy to the system. In a time crystal, electrons would travel in a loop rather than a line and occasionally bunch up rather than flow smoothly, repeating in time the way atoms in ordinary crystals repeat in space.

Jennifer Ouelette writes in New Scientist that this is indeed not just theoretically possible, but has been done, and could be maybe useful to built better quantum computers.

A strange material: Vanadium Dioxide. At certain temperatures it transports electricity, but not heat. That’s unexpected, because of the Widemann-Franz law, which says that the two should be related.

Another weird – but not new property of the material: transparent to around 30 degrees Celsius, but then reflects infrared while remaining transparent to visible light.

Coming up: Chinese New Year @ 28. Januar.

The coming year is a year of the Fire Rooster, and apparently these things mean a lot to a lot of people.

So what influence does the Chinese Zodiac have?

Well, one sign that is supposed to be very unlucky is the Fire Horse. An article from 2012 explains:

People born during the year of the Fire Horse are notorious for being bad luck. People born during a Fire Horse years are said to be irresponsible, rebellious, and overall bad news.

And for some reason, women are said to be especially dangerous Fire Horses. They supposedly sap their family’s finances, neglect their children, and drive their father and husband to an early grave.

Solution? Don’t make babies in a Fire Horse year, and especially no female babies.

So 1966 was a Fire Horse, and that’s what 1966 stats look like: