Saturday, March 25, 2017


Henry Cavendish performed one of the ten most clever science experiments in history in 1797 when he "weighed the earth".
John Walker recreated it in his basement.

A Winter Jacket winter, a spring jacket in spring.

Sunday, February 5, 2017

Visiting Other Stars

The Breakthrough Starshot project has a realistic plan for humans to have a spacecraft inside another solar system in 20-30 years. Their idea is to make a swarm of tiny vehicles. They would be thrown into space somehow and propelled onward using a lightsail. Power for the lightsail doesn't need to be stored on the ship. These ones would get little power from the sun. The light would come from a massive laser on earth. The physicists figure they can  achieve speeds of 1/5 the speed of light or 6000 km/s.

Each ship would have a mass of a gram or two. It would be a couple of cm in size but have a light sail that folds out to an area of 4m x 4m.

There are a lot of challenges: powering a computer for 30 years; recording, storing and transmitting photographs and video; cosmic rays; dissipating waste heat and impacts with space debris.

Ultimately, after all that journey, the craft would spend about two days travelling the distance of the earth's orbit.

If you want a ship that can take up orbit around the next star, that will take 100-150 years.

Wednesday, January 25, 2017

Bellyaching about Autism

Now there's a claim that gut bacteria is related to autism.
Apparently gastrointestinal  problems are common among those with autism. This study claims that a transplant of fecal microbes reduces gastrointestinal problems 80%, not too surprising. More remarkable is that it improves social and sleep habits by 20%.

Sunday, January 8, 2017

Dinosaurs Had Feathers

We have long imagined dinosaurs as mighty lizards: scales and all. Every once and a while it is good to be reminded just how little of what we know is fact and how much is speculation.

Our beliefs about dinosaurs are based on reconstructions of skeletons or parts of skeletons. No one has ever seen dinosaur skin.

Only now, it seems we may have seen the tail of a dinosaur, down to the smallest detail of texture, possibly even some hints of coloring.

Thursday, December 1, 2016

Cuban Life

There is a lot of romance about Cuba. At Castro's death, there has been an attempt to restart the flame. This article from travel journalist Michael Totten puts life for the average Cuban into perspective.

And it doesn't mention Concentration camps, executions, firing squads, the exodus, families fleeing by sea.

Friday, August 5, 2016

Kipling Readings

The Washington Post defends Rudyard Kipling from the fashionable haters. From my point of view it's a Reading list of Kipling, “the greatest short-story writer in English“.

Though I notice three major omissions: If, The Gods of the Copybook Headings * and Tommy.

Sometime in my twenties I noticed a trend.
The time has come to confess that I am an admirer.

(Feb'16) A real fan's guide

* And in song!
**not actually in twenties

Wednesday, May 25, 2016

Living in a Time of Wonders

Note that 1970 is just about exactly when your average North American decided that world poverty was a hopeless problem. 1990 was when international socialism collapsed.
Sept'16-Dierdre McCloskey hazards a guess as to why.

Monday, April 18, 2016

Slow Progress Expected for Zika
Above is an excerpt from an infographic for a Zika virus vaccine. It politely hints at the problem.
  1. Zika most strongly affects pregnant women and their newborns.
  2. Any tragedies, whether caused by the vaccine, unrelated to the vaccine or even mitigated by the vaccine will be blamed on the vaccine. There will be lawsuits and the damages will be astronomical.
  3. Revenue will not be astronomical. 
 (July'16) I'm not sure I like where this is going.

Sunday, April 17, 2016

Perceiving the Flow of Reality

It seems natural to say that we see the world as it is presented to us, a continuous flow of new situations and new information. On the other hand, if you've ever seen an optical illusion, you know that perception is imperfect. How do we interact with the world?
This study says that our perceptions come to us in the form of "'time slices' lasting only milliseconds." Our mind perceives the world as a moment: all at once for about a quarter of a second, then it goes on to perceive the next moment.
The description reminds me of Ridley Scott's filming technique in the most intense battle scenes of Gladiator. (starting at about 4 minutes)

Saturday, March 26, 2016

Professionalism and Professional Success like to think they go together. Here is an example of a doctor for whom they conflict.
“Why wouldn’t I give patients a Percocet prescription? It makes their life easier and my life easier.”

Wednesday, March 9, 2016

Do You See the Volcano Tornadoes?

The American Association of Physics Teachers has posted the results of its 2015 photo contest. Sure the pictures are great; even better are some of the explanations that go with the winners.

Sunday, March 6, 2016

Robots and Jobs

Are Robots Going to Take My Job?

I don't have an answer for that. The evidence I can muster says yes. My intuition says no. Scary stories are so much more compelling, though.

TaxProfBlog explains some of my thoughts on the subject. The Lump-of-Labour fallacy he mentions is outlined here.

(Dec'16) Ridley  says  no.

Thursday, February 18, 2016

Tuesday, February 16, 2016

DDT and the 100 Million
"In the last days of September 1943, as the U.S. Army advanced to the rescue of Italian partisans — some as young as nine — battling the Germans in the streets of Naples, the enraged Nazis, in a criminal act of revenge against their erstwhile allies, deployed sappers to systematically destroy the city’s aqueducts, reservoirs, and sewer system. This done, the supermen, pausing only to burn irreplaceable libraries, including hundreds of thousands of volumes and artifacts at the University of Naples — where Thomas Aquinas once taught — showed their youthful Neapolitan opponents their backs, and on October 1, to the delirious cheers of the Naples populace, Allied forces entered the town in triumph."

"But a city of over a million people had been left without sanitation, and within weeks, as the Germans had intended, epidemics broke out. [read on]"

Saturday, February 13, 2016

Gravity Waves

The news says gravity waves have been discovered. The headlines say "Einstein proven right" though really, the physics world was not all that apprehensive. The excitement is that we now have a new way to look at the world. has a good news release with a video on the implications. Ricochet explains the experiment for an adult layman audience. This Verge video has the background, like how Einstein's concept of gravity is like bending space instead of Newton's idea of a force.

Sunday, January 31, 2016

Progress Towards Life on Mars

 A fungus from Antarctica has been proven to survive reasonably well in simulated Mars conditions.

This means that if we decide* to make Mars habitable, the technology to do so is at hand. We can send earth life that will survive and reproduce. If the photosynthetic species are also hardy enough, we can generate oxygen that would stabilize the atmosphere.

*That is to say, unless we have already sent it.

Friday, January 29, 2016

So, you're stranded on a desert island. You can find food for now. You are surviving.

It can get cold, though and you are unprotected. You'd like to make your little world better than it is. Unfortunately, you have none of the modern tools you take for granted. You need primitive technology.