The Minute Physics Interactive Periodic Table of Awesome

Henry Reich and Jasper Palfree have created an amazing interactive version of the Periodic Table. As you change temperature, you can see the elements transition between different states of magnetism. You can also see at what temperatures an element changes state from solid to liquid to gas. There is even an option to display temperatures in Fahrenheit for the heathens among you. Interactive Periodic Table If that isn’t awesome enough, Henry makes clever use of Youtube, HTML5, and the interactive periodic table to explain how to destroy a magnet. You can also click on any element to see a clip, courtesy of Periodic Videos, about it. This is a great educational tool. I can’t wait to see what Henry and Jasper come up with next.

Connection Doesn’t Work the Way You Think It Works

Rebecca Brightly:

Traditionally, the lead is in charge of the entire structure of the dance. The lead must give the follow clear instructions. Traditionally, the follow has limited choices, and all choices must mesh with the lead’s instructions.

First, the traditional definition is literally inaccurate. Of course you can dance that way. But the best dancers do not. The best dance partnerships work as a team, both people contributing creative ideas on the fly, each responding to the other’s movements, adapting the direction of the dance based on their partner’s input.

This is a must-read article on the subject of connection in dance. One of the biggest breakthroughs in my own dancing came when I realized that the lead can initiate a movement that the follow then completes. How a follow chooses to move in response to the lead is where much of their creativity is expressed. This movement then influences how the lead subsequently moves, and the cycle continues.

lindy hop connection yin yang

The best dances I have occur when ideas flow back-and-forth seamlessly. The distinction between leading and following disappears, and the dance becomes about two people together weaving something beautiful out of the music and movement they share. Yin & Yang. Lead & Follow.

I Charleston the World

The idea is simple–”make videos of you doing Charleston in front of famous places around the world… and share.” So far over two-dozen videos have been submitted. This one from Berlin is my favourite. Excellent dancing and production values.

UPDATE This video from Nashville, released today, gives the Berlin one a run for its money. Great song choice.

Canon develops amazing low-light sensor

Canon has just announced a new 35 mm full-frame sensor that is incredibly sensitive to low-light levels. The sensor does this in part by using large pixels (19×19 microns^2), which is about 7.5 times larger than the pixel size of their other cameras.

Right now the sensor is optimized for full-HD video. Here is the video Canon has released of some footage from a sensor prototype. Most impressive are the shots of the Milky Way, illuminating a person using an incense stick, and being able to shoot in moonlight as if it were daylight.

So just how sensitive is this camera? According to the specs, the camera can form a useable image at ~0.03 lux. Doing a quick back-of-the-envelope calculation, 0.03 lux corresponds to a sensitivity of about 40,000 photons hitting each pixel each second (for green light). If we shoot at 24 frames/second, this is about 2000 photons/frame/pixel–or about 0.5 femtowatts.

Any sensor will have noise associated with it. In order to get a useable image, you should have a decent signal to noise ratio. Let’s say that 5% of the pixels have noise on them (corresponding to a fairly noisy image), that means each pixel experiences about 100 noise counts/second.

What is remarkable is that this takes place at room temperature. There are other sensors that have been developed for scientific applications that are much more sensitive than this Canon camera, but they must be cooled first. For example, a camera I have worked with in the past is the Andor iDus. This camera is sensitive down to the single-photon level when cooled to -80 C. This is achieved in part by using some clever electronics to reduce the readout noise and using larger pixels (26×26 microns^2). At -80 C, the camera experiences a negligible amount of dark counts/s (much less than 1). Increase this to 20 C (room temperature), and that number goes up to a couple of hundred noise counts/pixel (as best as I can tell from the specs).

This analysis should be taken with a grain of salt. The take home message is that at room temperature, the new Canon CMOS sensor performs on par with the best EMCCD cameras out there. This is seen in Canon’s own tests (where they measure against a three-EMCCD). It would be interesting to see how well this new sensor performs when cooled.

I can’t wait for this technology to eventually make its way into consumer-level technology.

Screen shots from the Canon Video

This scene is illuminated only by moonlight.

This scene is illuminated only by moonlight.

An incense stick is bright enough to illuminate a man's face.

An incense stick is bright enough to illuminate a man’s face.

A comparison between a three-EMCCD and the new Cannon sensor.


Grammar that!

Brilliant takedown of a grammar jerk in the comments at Ars Technica. User Kikjou writes: “Bacteria is plural of bacterium. Please use is correctly. The same goes for media and medium, which is not in this article but is often misused in scientific writing.” To which Ars Centurion Okton responds:

In Latin maybe. And the phrase you are nitpicking is actually “from a bacteria”. So if you were anything but pedantic, you would exclaim “that requires the ablative of source! In the singular.” Following your logic, the article should read “…from a bacterio”. But wait, Latin has no indefinite article, so whether it is “a bacterium” or “a bacterio”, the noun phrase is redundant since indefiniteness is presupposed in simple noun forms. But “from bacterio” is neither grammatical English nor comprehensible Latin. And the ablative of source usually employs a preposition, so “from a bacteria” should read “ab bacterio” to be exact.

Problem is: This is not FRICKING Latin. This is a word of Latin origin that has entered into English. Therefore our rules apply. Because if you demand a Latin singular, I demand the proper Latin case, pronunciation, etc. We took the plural form for obvious reasons. Because of the physical size of bacteria, the word became a mass noun and functions as both plural and singular. Same reason for taking “data”: it is collective. There are rarely “bacterias”. And certainly no “datas”. One sheep. Two sheep. Ten sheep. One form, all numbers. It is legal in English – accept it.

I can only assume you are one of those people who thinks the plural of “octopus” is “octopi” as well. Except there is no such word as “octopus” in Latin. The word is “polypus”, “Octopus” is from the Greek ὀκτάπους, and the plural of that is ὀκτάποδες. And even if people knew “octopodes” was the true plural, they would say it wrong since the epsilon is not silent. Why? Because it is adapted for usage in the new language. It has no obligations to its old morphology and phonology.

By your inanity, if you ever say the word “cherry” for a single unit, I have every right to chastise you. That word never existed in French. “Cheris(e)” is the singular form that was introduced into English. How dare you impose English conventions of depluralization on it! You will say “Shair-eez” for one piece of fruit, you’ll do it in a beret and you’ll like it. You doctrinaire dope.

via Ed Yong

Nature acquires open access publisher Frontiers

Nature, the scientific publishing behemoth, has acquired the upstart open-access publisher Frontiers. It will be interesting to see how this will shake out; will Nature publications move towards a more open access model, or will Frontiers shift to a more traditional model?

Scientific publishing is big business. From the Economist article:



In comparison, $6 billion dollars a year is more revenue the music industry generates from iTunes1 ($5.6 billion), or iOS developers make from the App store2. Scientist must pay significant fees to publish their articles, and then institutions have to pay even larger fees to access the research. Now, with the internet, it is becoming possible to publish in journals or preprint servers that anyone can access. In physics things are already moving this way with the advent of the Arxiv, a free online repository that contains a mix of peer-reviewed and non-peer-reviewed work:

ArXiv is already hosted by Cornell University at a cost of around $830,000 a year. Tacking on an “epijournal”, so that referreed papers would sit alongside the original preprints, for instance, should not add too much on top of that.

The idea makes perfect sense. Scientists already do most of the heavy lifting involved in publishing research: they write up and format papers, post them to online servers, sit on journals’ editorial boards and review their colleagues’ work. One reason for Elsevier’s mouth-watering margins is that this work is typically done for no compensation.

With that much money at stake, it will take some time for things to change.