There Is No Parity: Chien-Shiung Wu

September 28, 2017 by Will Sweatman 68 Comments

Hold out your hands in front of you, palms forward. They look quite similar, but I’m sure you’re all too aware that they’re actually mirror images of each other. Your hands are chiral objects, which means they’re asymmetric but not superimposable. This property is quite interesting when studying the physical properties of matter. A chiral molecule can have completely different properties from its mirrored counterpart. In physics, producing the mirror image of something is known as parity. And in 1927, a hypothetical law known as the conservation of parity was formulated. It stated that no matter the experiment or physical interaction between objects – parity must be conserved. In other words, the results of an experiment would remain the same if you tired it again with the experiment arranged in its mirror image. There can be no distinction between left/right or clockwise/counter-clockwise in terms of any physical interaction.

Dr. Wu working with a particle accelerator via Biography.

The nuclear physicist, Chien-Shiung Wu, who would eventually prove that quantum mechanics discriminates between left- and right-handedness, was a woman, and the two men who worked out the theory behind the “Wu Experiment” received a Nobel prize for their joint work. If we think it’s strange that quantum mechanics works differently for mirror-image particles, how strange is it that a physicist wouldn’t get recognized just because of (her) gender? We’re mostly here to talk about the physics, but we’ll get back to Chien-Shiung Wu soon.

The End of Parity

Conservation of parity was the product of a physicist by the name of Eugene P. Wigner, and it would play an important role in the growing maturity of quantum mechanics. It was common knowledge that macro-world objects like planets and baseballs followed Wigner’s conservation of parity. To suggest that this law extended into the quantum world was intuitive, but not more than intuition. And at that time, it was already well known that quantum objects did not play by the same rules as classical objects. Would quantum mechanics be so strange as to care about handedness? Continue reading “There Is No Parity: Chien-Shiung Wu” →

Spy Tech: Nonlinear Junction Detectors

September 20, 2017 by Al Williams 122 Comments

If you ever watch a spy movie, you’ve doubtlessly seen some nameless tech character sweep a room for bugs using some kind of detector and either declare it clean or find the hidden microphone in the lamp. Of course, as a hacker, you have to start thinking about how that would work. If you had a bug that transmits all the time, that’s easy. The lamp probably shouldn’t be emitting RF energy all the time, so that’s easy to detect and a dead give away. But what if the bug were more sophisticated? Maybe it wakes up every hour and beams its data home. Or perhaps it records to memory and doesn’t transmit anything. What then?

High-end bug detectors have another technique they use that claims to be able to find active device junctions. These are called Nonlinear Junction Detectors (NLJD). Spy agencies in the United States, Russian and China have been known to use them and prisons employ them to find cell phones. Their claim to fame is the device doesn’t have to be turned on for detection to occur. You can see a video of a commercial NLJD, below

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In-Band Signaling: Quindar Tones

September 19, 2017 by Dan Maloney 29 Comments

So far in this brief series on in-band signaling, we looked at two of the common methods of providing control signals along with the main content of a transmission: DTMF for Touch-Tone dialing, and coded-squelch systems for two-way radio. For this installment, we’ll look at something that far fewer people have ever used, but almost everyone has heard: Quindar tones.

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A Video Game Odyssey: How Magnavox Launched The Console Industry

September 14, 2017 by Al Williams 23 Comments

What was the first video game console? If you said the Atari 2600, you would be wrong, but we’d forgive you. After all, the Atari was early and widely sold. It also had the major features you expect from a video game. However, there was an earlier console available. the Magnavox Odyssey.

This system was black and white, had two wired controllers, and while it didn’t quite have cartridges, you could select from one of several games. The system seems inexpensive today at $100 (not including the optional light gun). However, adjusting for 1972 currency value, that’s equivalent to about $600 today.

It was not an impulse buy, and the differentiation between games was mostly an exercise in imagination. But the the Magnavox Odyssey nevertheless brought computer technology into the home and that was exciting. It proved a market existed for home video gaming, and served no small part in the success of Atari.

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I’ve Seen The Future And It’s Full Of Freakin’ Huge Bricks

September 8, 2017 by John Baichtal 31 Comments

“Did you know you can 3D-print LEGO bricks that can actually be used as regular LEGO?”–me, in 2009

Those magical words made real to me the wonder that was 3D printing. It was a magical time! Everyone was 3D printing everything, though most of it wasn’t very good because the technology wasn’t there. But just as every technology goes through an evolution, the goalposts of coolness move on past what used to be remarkable to the new thing everyone’s talking about.

These days, no one is going to be more than mildly curious about your 3D-printed LEGO brick. Still, when you look at that uneven lump of plastic as being just one step in an evolution, it’s pretty momentous. What I’m saying is that we’re looking at a future that can be described in three words: Freakin’ Huge Bricks.

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In-Band Signaling: Dual-Tone Multifrequency Dialing

September 5, 2017 by Dan Maloney 43 Comments

One late night many decades ago, I chanced upon a technical description of the Touch-Tone system. The book I was reading had an explanation of how each key on a telephone sends a combination of two tones down the wire, and what’s more, it listed the seven audio frequencies needed for the standard 12-key dial pad. I gazed over at my Commodore 64, and inspiration hit — if I can use two of the C64’s three audio channels to generate the dual tones, I bet I can dial the phone! I sprang out of bed and started pecking out a Basic program, and in the wee hours I finally had it generating the recognizable Touch-Tones of my girlfriend’s phone number. I held the mouthpiece of my phone handset up to the speaker of my monitor, started the program, and put the receiver to my ear to hear her phone ringing! Her parents were none too impressed with my accomplishment since it came at 4:00 AM, but I was pretty jazzed about it.

Since that fateful night I’ve always wondered about how the Touch-Tone system worked, and in delving into the topic I discovered that it’s part of a much broader field of control technology called in-band signaling, or the use of audible or sub-audible signals to control an audio or video transmission. It’s pretty interesting stuff, even when it’s not used to inadvertently prank call someone in the middle of the night. Continue reading “In-Band Signaling: Dual-Tone Multifrequency Dialing” →

Way To Go, Einstein; His Time Spent Being Wrong

August 31, 2017 by Will Sweatman 116 Comments

When you hear someone say “Einstein”, what’s the first thing that pops into your head? Is it high IQ… genius… or maybe E=MC²? Do you picture his wild grey hair shooting in all directions as he peacefully folds the pages back from his favorite book? You might even think of nuclear bombs, clocks and the Nobel Prize. It will come as a surprise to many that these accomplishments were a very small part of his life. Indeed, Einstein turned the world of classical physics upside down with his general theory of relativity. But he was only in his early twenties when he did so.

What about the rest of his life? Was Einstein a “one-hit-wonder”? What else did he put his remarkable mind to? Surely he tackled other dilemmas that plagued the scientific world during his moment in history. He was a genius after all… arguably one of the smartest people to have ever walked the earth. His very name has become synonymous with genius. He pulled the rug out from under Isaac Newton, whose theories had held the universe together for over 300 years. He talked about enigmatic concepts like space and time with an elegance that laid bare the beauty hidden within their simplicity. Statues have been made of him. His name and face are recognizable across the globe.

But when you hear someone say “Einstein”, do you think of a man who spent the better half of his life… being wrong? You should.

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