Bertlmann’s Socks And The Nature Of Reality

October 6, 2015 by Will Sweatman 50 Comments

The philosopher in the street, who has not suffered a course in quantum mechanics, is quite unimpressed by the [Einstein-Podolsky-Rosen] correlations. He can point to many examples of similar correlations in everyday life. The case of Bertlmann’s socks is often cited. Dr. Bertlmann likes to wear two socks of different colours. Which colour he will have on a given foot on a given day is quite unpredictable. But when you see that the first sock is pink you can be already sure that the second sock will not be pink. Observation of the first, and experience with Bertlmann, gives the immediate information about the second. There is no accounting for tastes, but apart from that there is no mystery here. And is this [Einstein-Podolsky-Rosen] business just the same?

John Bell began his now famous paper with the above paragraph. The Bell Inequality started off like so many other great theories in science – as a simple thought experiment. Its conclusions were not so simple, however, and would lead the way to the end of Einstein’s idea of local hidden variables, and along with it his hopes for a deterministic universe. In this article, we’re going to look at the Bell inequality in great detail. Our guide will be a chapter from Jim Baggots’ The Quantum Story, as it has one of the best descriptions of Bell’s theory I’ve ever read.

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3D Printed Plane Flies High

October 6, 2015 by James Hobson 12 Comments

One of our avid readers, [Niklas Melton] loves RC planes. After getting into 3D printing, the next logical step was to start building is own planes… And now he’s done it!

He calls it the Air-Form 1 Micro RC plane, paying homage to the FormLabs resin printer he used. All of the parts except for the electronics were printed using a tough resin. It’s designed to take balsa wood wings into clips he designed into the parts. A 150mAh battery provides the power with a motor that exerts about 54g of thrust — not bad considering the entire thing only weighs 60g! Unfortunately he doesn’t have any video clips of it flying, though he assures us it does indeed fly — if you’re interested in building your own, he’s uploaded all the files to a page on Thingiverse.

As more advanced 3D printers come down in price, like the SLA technology, it becomes possible to design and 3D print even more complex parts. Some of the resins available have now some pretty amazing properties. One of our readers replaced a servo spline gear with one he printed — which works even better than the original!

Electronics For Aliens

October 6, 2015 by Nava Whiteford 79 Comments

We are surrounded by displays with “millions” of colors and hundreds of pixels per inch. With super “high fidelity” sound producing what we perceive to be realistic replicas of the real world.

Of course this is not the case, we rarely stop and think how our electronic systems have been crafted around the limitations of human perception. So to explore this issue, in this article we ask the question: “What might an alien think of human technology?”. We will assume a lifeform which senses the world around it much as we do. But has massively improved sensing abilities. In light of these abilities we will dub it the Oculako.

Let’s begin with the now mostly defunct CRT display and see what our hypothetical alien thinks of it. The video below shows a TV screen shot at 10,000 frames per second.

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Take Your Robots Tubing

October 6, 2015 by Al Williams 16 Comments

When you think of a robot, you might think of one with wheels, tracks, or even legs. But today’s robots are as likely to have wings, props, or even some way to propel it through the water. If you are bored with quadcopters and want to build a water-going robot, you should check out Jalcboat, an open source robot/boat. Although the project is under development, the videos (see below) show that they’ve made a good bit of progress.

As you might expect, 3D printing is a key ingredient and the files are available on Thingiverse linked above. In addition, the robotic boat has a Raspberry Pi onboard to control brushless motors. The main web site is more of a discussion forum and some of it is in Spanish, so you might want to keep Google translate handy.

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Light Speed: It’s Not Just A Good Idea

October 6, 2015 by Al Williams 31 Comments

[Kerry Wong] took apart a PM2L color analyzer (a piece of photography darkroom gear) and found a photomultiplier tube (PMT) inside. PMTs are excellent at detecting very small amounts of light, but they also have a very fast response time compared to other common detection methods. [Kerry] decided to use the tube to measure the speed of light.

There are several common methods to indirectly measure the speed of light by relating frequency to wavelength (for example, using microwave ovens and marshmallows). However, measuring it directly is difficult because of the scale involved. In only a microsecond, light travels almost 1000 feet (986 feet or 299.8 meters).

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Your Steaks Sleep With The Fishes In This Giant Sous Vide Aquarium

October 5, 2015 by James Hobson 21 Comments

A small engineering company in Germany called [Nerdindustries] decided to throw a party, and in doing so, wanted to squash some rumors that nerds only eat pizza and take out. We’d say they successfully one-uped their friends while proving they too can make gourmet food. The gathering included a massive sous vide cooker out of an old 240L aquarium. Be warned, their website presentation is rather annoying but worth it.

They got the aquarium off eBay for $40, and started the project by resealing the aquarium with some silicone. Water adding some aluminium extrusion they mounted six immersion heaters. Three to heat it to temperature, and another three running off a PID control loop with waterproof temperature sensors to maintain it within a degree or so. Of course that wouldn’t get you very far unless you completed the build by filling the aquarium with water.
To make it a bit fancier for the party, they also threw a projector above it to display some simple visuals in the water. For their big night, they cooked steaks at 60C for about an hour and a half, and then finished in a pan to sear before serving — they were a hit. There’s a video on the site, but we can’t embed it here, so you’ll have to go check it out!

Is Sous Vide still a hot topic with hackers? There was a flurry of activity a few years back (Sous Vadar obviously one of our favorites) but we haven’t seen nearly as many projects lately. Actually we recently saw a Sous Vide repurposed for brewing instead of cooking.

Georgia Tech Pumps Water Through Silicon For Chip Cooling

October 5, 2015 by Al Williams 72 Comments

One of the things that stops electronic devices from going faster is heat. That’s why enthusiasts go as far as using liquid nitrogen to cool CPU chips to maximize their overclocking potential. Researchers at Georgia Tech have been working on cutting fluid channels directly into the back of commercial silicon die (an Altera FPGA, to be exact). The tiny channels measure about 100 micron and are resealed with another layer of silicon. Water is pumped into the channels to cool the device efficiently.

A comparable air-cooled device would operate at about 60 degrees Celsius. With the water cooling channels cut into the die and 20 degree water pumped at 147 ml/minute, the researchers kept the chip operating about less than 24 degrees Celsius.

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