“Any sufficiently advanced technology is indistinguishable from magic.” -Arthur C. Clarke
Many of the technologies we make use of on a daily basis would be considered magic to most people two centuries ago. Even today, many people wouldn’t be able to explain to you how some modern devices function. But not only is the science behind modern technology not always understood, it isn’t even appreciated.
Here are six wondrous technologies that we take for granted – and complain about.
1. Internet Access
“Ugh, the wireless signal here is so weak.”
The great network of networks is a magical wonder unto itself, but even the way we access it is incredible. Information – text, images, videos – is encoded into a signal and sent through wires and sometimes thin air for us to capture and decode.
In the days of yore, dial-up was the common form of Internet access. A modem over at your Internet Service Provider would take digital data, modulate it into an electrical signal, and transmit that signal over telephone wires, whereupon your modem would receive the signal and demodulate it. The word modem, itself, is shorthand for “modulator-demodulator.”
Today, broadband is the new norm in most places. Rather than telephone wires, most broadband uses coaxial, fiber optic, or twisted pair cables to carry more data. DSL actually still uses telephone wires, but unlike dial-up, it sends the data at higher frequencies, resulting in faster speeds and the ability to simultaneously use the Internet and telephone – no more horrid modem screeching sounds!
Wi-Fi is able to wirelessly broadcast the modulated signal across local area scales using radio waves emanating from an access point, like a router. A mobile broadband modem or data card can plug into a laptop to allow access to wireless Internet, and most mobile devices nowadays include built-in means of wirelessly accessing the Internet.
So the next time you get irritated by slow Internet speeds, take a moment to appreciate the fact that you are surrounded by invisible information beams.
2. Computers
“My stupid computer froze…”
Your computer is a magic box that makes your life better. A laptop is a portable computer, and a smartphone or tablet is an even more portable computer that is still more powerful than most of the computers that were around 25 years ago.
At the heart of a computer is a piece of hardware known as the central processing unit (CPU), which executes programs – sequences of instructions. While programs are written in a way that is easy and convenient for a trained human programmer to read, they are generally converted to a series of 1s and 0s for the computer to read: binary code. These 1s and 0s are just the representation of a “bit,” which is the most basic unit of information in computing. On the hardware, every bit is represented by a tiny electrical circuit – computers can have thousands to trillions of these. A bit – short for “binary digit” – can only have two values (typically represented as a 1 or a 0), and this corresponds to turning one of those circuits either on or off. Computers execute billions of calculations per second to interpret binary code.
The convenience, entertainment, and capabilities computers add to our lives have become almost indispensable in today’s world. The next time you get annoyed at your computer, try going a week with only an abacus.
3. Digital Cameras
“Ugh, this picture came out terribly.”
Whether it’s your smartphone’s camera, your webcam, or even – gasp – an actual camera, this tiny device is able to capture and store still and moving images at the press of a button. Unlike older cameras, digital cameras use electronics rather than chemicals to process the image – and it’s ready for viewing instantaneously.
Digital image sensors turn incoming light into discrete digital signals. The number of pixels in the sensor determines the camera’s pixel count, so an 8 megapixel camera has 8 million pixels. Like in a traditional camera, a digital camera uses a diaphragm and shutter to focus the correct amount of light onto the imager – in this case, the sensor – and the more light a given pixel receives, the larger the value that is digitally assigned to it. The sensors themselves are only sensitive to the intensity of the light – how dark or bright it is – and not the color, so additional color filters must then be used to process color information. In typical cameras, overtop every pixel is a single color filter than can measure the intensity of either red, green, or blue light (determined by targeting specific wavelengths of light). These color filters are arranged in a mosaic pattern, and digital processing then interpolates these discrete color data points into a full-color image.
So the next time you complain about how that selfie turned out, try hiring an artist to follow you around and paint your portrait.
4. GPS
“Ack, stupid GPS thinks I’m on the wrong street.”
Whether it’s a service on your smartphone or a dedicated device, GPS means future generations will never bother to learn how to read a map. A paper map, not a Google Map.
Standalone GPS uses satellites and software to determine your location data. GPS satellites are continuously transmitting their current position and the time of transmission via radio signals. Your GPS receives these messages and is able to determine your distance from the satellite based on the current time and the transmitted data: the satellite’s position and how long ago the message was sent. Since we know the speed at which the data travels, your distance to the satellite is easily calculated. If that distance is, say, 20,000 km, that means you can be anywhere along the outer edge of a 20,000 km sphere around the satellite. That’s why your GPS pulls data from four satellites to determine your position: the point at which four spheres intersect.
Assisted GPS, found in most smartphone GPS devices, additionally connects to an internet network to deliver faster and more precise results. It can take 30-40 seconds for a standalone GPS to “find” the nearest satellites and start giving you positional information. Assisted GPS will download the orbital position of GPS satellites to cut down on that time, and a lot of the processing can be offloaded to the server – which will have a more powerful computer than your mobile device.
The next time you complain about your GPS, consider that you’re accessing equipment floating around in space – you know, that place that astronauts visit?
5. Airplanes
(Warning: profane language in the video.)
“Oh my God, that three-hour flight was BRUTAL.”
An airplane is a seemingly gravity-defying metal tube with wings that enables you to travel faster than has ever been possible in history. Big airliners use jet engines for propulsion, burning jet fuel at about 1,000 degrees Celsius and spinning rotors up to 15,000 times per minute – yet they remain safer than many other modes of transportation.
Airplanes are able to fly through thrust and lift. When thrust – generated by a propeller or jet engine – moves a plane forward, it is the movement of air over and under the wings that generates the lift needed to get and keep the craft airborne. The wing is specifically shaped to deflect air above and beneath it in such a way as to create a zone of low pressure above the wing relative to beneath it. The pressure difference results in an aerodynamic upward force that creates the lift.
The next time you’re on an airplane and unhappy about your seating, remember the words of comedian Louis C.K.: “You’re sitting in a chair in the sky! You’re like a Greek myth right now!”
6. Electric Power
“Stupid, crappy smartphone battery… I have to charge this thing every night.”
None of these technologies would be possible without Zeus’ blessing. Through his divine will, lightning courses through wires and electronics, bringing them to life.
To put it more complexly, an electric generator converts mechanical energy into electrical energy by moving an electrically conductive material around inside a magnetic field. inducing a current of charged particles. An electrical grid consists of generators that transmit electrical power along transmission lines to where it’s needed. In order to transmit power over great distances, the voltage is “stepped up” significantly, before being “stepped down” again to the voltages needed to power your home and appliances. The reason for this is that power is lost during transmission, and higher voltages result in less transmission loss.
A battery stores chemical energy and converts it into electrical energy when needed. Within a battery is one or more electrochemical cells, which generate electrical energy through chemical reactions. Each of these cells contains a positive and a negative terminal, and current flows from one end to the other through either a liquid or solid solution that is electrically conductive.
In a regular battery, the chemical reaction that generates electrical energy causes irreversible changes to the materials inside. In a rechargeable battery, by reversing the current flow, the changes can be reversed, allowing the battery to be used multiple times.
Before you complain about your smartphone battery again, consider that you’re carrying with you a power source whose potential can be unleashed at your command. You used to need slaves for that.
