NASA is phasing the Space Shuttle out of service. Without the Space Shuttle, how will we send people into space? The Saturn V rockets of the Apollo program were effective, but they used vast amounts of fuel. It is time for some innovation. We have relied on chemical fuel rockets for half a century. We need a better way of getting to space.

One major drawback for chemical rockets is the weight of the fuel itself. The fuel's combustion has to generate enough thrust to lift both the fuel and the rocket/payload. The Space Shuttle has a mass of 100,000 kilograms, but when combined with its rockets there are 2,000,000 kilograms that need to lift off the ground. The energy for thrust is stored in the fuel's chemical bonds, and the energy density is limited. It might be better to store the energy on the ground, and beam that energy to the spacecraft during liftoff. That way, a lot of energy can be combined with less fuel to produce the same or more thrust. A powerful laser facility would act as a launch base. With a constant supply of energy, it could launch commercial satellites much more often—and more cheaply—than rockets. If you want to launch two rockets in one day, then you need to build two rockets. With laser propulsion, you only need to build one laser facility and fire up the lasers twice.

A vessel built for laser propulsion focuses (with optics or heat exchangers) laser beams from the ground to ignite either some propellant or just the air below. A continuous or pulsating (depending on the type of laser) explosion is created, but without combustion of conventional rocket fuel. The vessel gets its propelling energy from the light of the laser beam, not chemical bonds in expensive fuel, and the “lightcraft” is propelled upwards. This is the principle behind laser propulsion.

Scaling up payloads should be easier with laser propulsion. With rocket-propelled spacecraft, you need more or bigger rockets to launch heavier payloads. As mentioned earlier, the weight of the fuel itself is a problem. But with laser propulsion, you can simply add more lasers on the ground and aim them all at the same point. This way you get more thrust without adding more heavy fuel tanks.

One problem is keeping the lightcraft stable during launch. Current scaled-down prototypes spin at high rates in order to fly straight up. Such spinning might not be desirable for a full scale lightcraft. If the whole vessel rotated while carrying passengers, they would get sick, or worse. Perhaps a large gyro could be used instead of spinning the whole craft, but that would add to the overall weight.

Another obstacle for laser propulsion is the power of lasers. It takes about one megawatt of laser power to lift one kilogram of lightcraft into space. The Space Shuttle weighs about 100,000 kilograms so launching a lightcraft as massive as a Space Shuttle would require around 100,000 megawatts (100 gigawatts) of laser power. To put this into perspective, think about some real-world lasers and their outputs. Common laser pointers have power ratings under 5 milliwatts (0.000005 megawatts). The military laser, ZEUS, has a power rating of 10 kilowatts (0.01 megawatts). The Nova laser, part of a nuclear fusion project, was capable of 16 terawatts (16,000,000 megawatts) in very short bursts. Roughly, you would need 10,000,000 ZEUS lasers to send a Space Shuttle into low orbit, or 500,000 to send a 5,000 kg Apollo lunar module. Considering the energy supply for such laser power, a nuclear power plant generally produces around 1,000 megawatts of electricity.

The limitations in engineering and powering of lasers makes lightcraft best suited for very small satellites. This could be beneficial for research institutions and companies that want to put equipment into orbit but cannot afford big rockets. Also, cargo and spacecraft could be sent up in pieces, then assembled in orbit. Perhaps in the future rockets will be limited to large payloads, and lasers will routinely launch anything under a certain weight limit. With technology improving all the time, microsatellites might become common and affordable.

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This summer, there will be laptops for sale that run on Google's Chrome operating system. For five hundred dollars you get a computer that lasts around eight hours per charge, uses up-to-date software, and even has some free 3G access (100MB). With any luck, the new operating system will run much smoother than Windows. The most interesting aspect is in how the laptops function. Most of the data storage and processing does not occur within the laptops themselves, unlike most computers, but on the internet. These “Chromebooks” might just be the way of the future.

As soon as you buy a traditional computer, it begins to depreciate. New, more powerful computers are constantly being put on the market, and products from previous years are rendered obsolete. The same principle applies to virtually all electronics, especially cellphones and cameras. You want the fastest computer available right now, but in a few months' time there will be a new line of even faster ones. What if you only had to buy a new computer every decade to keep up with the times?

The internet is a worldwide network of computers. If you could relegate an individual computer's processing to the many computers of the internet, then that computer would exceed the limitations of its own specifications. The process is analogous to a desktop computer. When you edit a typed essay on a desktop, the text file is stored in the CPU. But you see the file with a monitor, and you edit the file with a keyboard and mouse. With a Chromebook, you may see and edit a file from the laptop itself, but the actual file is stored and processed on Google's servers. This is called “cloud computing.” Because most of the computing performance happens on the internet, you should not need to buy a new Chromebook nearly as often as a conventional laptop.

What's the catch? The obvious weakness of this technology is the internet connection. If you lose your connection, then you do not have access to your files. For people with constant, stable connections, this trade-off could be very acceptable. Another problem is on the servers' end. What if the company hosting your files goes out of business? Or some sort of damage happens to the servers? Then all your files would be lost forever, unless you had a backup hard drive, of course.

Cloud computing might revolutionize the computer industry. Imagine, in the future, buying a laptop for a few hundred dollars, but—because it uses cloud computing—its performance will be on par with conventional laptops that cost over a thousand dollars. You never need to worry about updating your software since it happens automatically. If market growth is manageable, then the computing power should steadily increase as Google updates its servers' hardware. Perhaps for an hourly fee, you can boost your computer's processing speed to that of a supercomputer. As Google increases its data storage capacity, your own allotment grows, too, like with inbox storage on Gmail. That way, you can store more and more data without buying additional hard drives. Data storage and processing might one day be treated similarly as electricity and warehouse space. Computing will be a centralized commodity, and personal computers will be simple interfaces that access that resource from a distance. Cloud computing could also radically change the video game industry. Game consoles currently require expensive processors and graphics cards, but someday they may become slim and cheap interfaces. Imagine just buying a game controller without the console. The controller communicates with your Chromebook which is connected to the internet. Signals from the controller are sent to a gaming computer network, where those signals are interpreted. The game's response is sent back to the computer and displayed on the screen. This all happens so fast that you cannot perceive any delay. Eventually, a Chromebook, controller, and a fast internet connection might be all you need to play video games from any platform. What will that do to the industry? This separation of interface from actual computing may become a growing trend. It is quite probable that we will eventually have low-cost laptops that are constantly connected to cloud networks, making them portable supercomputers.

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Have you ever thought about it? Surfing the web is a new and unique experience in humanity's history. Never before have we been given access to so much information and at such speed as today. The internet is fundamentally changing how we interact with each other and the world around us. What, specifically, does this mean for our brains, our thought patterns, and our culture?

The internet is perhaps the most influential invention ever contrived. The spread of ideas has long been the source of change in the world. Throughout history people have killed and been killed for the sake of spreading or halting information. The old sayings, “the pen is mightier than the sword,” and “loose lips sink ships,” are testament to the power of ideas. A connection to the internet allows people to share and find ideas almost instantaneously. This means a lot of change can happen to societies very quickly. Political alliances can be forged through social networking. Scientists can share theories and data with each other very easily. Money can be exchanged and earned in new ways. Children in poor countries can benefit from the academic resources of wealthy nations. These are macroscopic effects, but changes to a single brain are microscopic in scope.

The brain is marvelously able to change its “wiring” in order to adapt to different environments. This plasticity allows people to adjust to new careers, learn to read, cope with blindness, and much more. As a person gets accustomed to using the internet, that person's brain “rewires” itself to interact more effectively with cyberspace. The internet is full of distractions, namely links and advertisements. It also makes being distracted very pleasing. Stray thoughts are easily pursued by opening additional browser tabs and using search engines. You could be right in the middle of reading a news article when you think about what tomorrow's weather will be like. A couple clicks later and you are dreading the impending snow storm. Then you go back to the article and try to remember where you left off. A few minutes later you think about checking your email and promptly do so. All along you might have been receiving and responding to text messages on your phone. From your perspective this may seem like harmless multitasking, but your brain is being spoiled by instant gratification. Over long periods of time, excessive internet use can make people generally impatient and prone to distraction. The brain learns that distractions are okay and interruptions are enjoyable. We like constant updates nowadays, but previous generations were accustomed to longer periods of sustained attention—focusing on each task until it was finished. For them, mail was received once a day or even less often. They read about topics one at a time and usually in some logical order. Today, reading on the internet is directed by the stream of consciousness, and topics can be quite random. Switching between multiple webpages will break a reader's concentration and increase the cognitive load. That means your brain must work harder to keep track of what you are reading, and less mental energy is used to absorb and process the information on those pages. In accordance with that change in behavior, the brain becomes better at managing multiple tasks and worse at reading comprehension.

Slow reading is good for maximizing the intellectual benefit of textual information. But information is no longer a scarce commodity. Rather than straining to get new information, we are now striving to contend with an overabundance of content. People are finding new ways to organize, search, and analyze the vast amounts of data provided by the internet. On a personal level, people tend to forgo slow reading and adopt skimming as their primary reading method. With so much content to absorb, it is difficult to slow down one's reading for fear of missing out on something. People learn about more varied topics, but they have only a passable understanding of each one. In this way, the internet makes more people “well-rounded,” but it subtly hinders any achievement of expertise by overfeeding us with content. Where does this copious content come from, anyway?

The internet creates a two-way stream of information. Not only can data be downloaded, but it can be uploaded, too. Every time someone sends a tweet, uploads a video, creates a blog post, edits a Wikipedia page, or updates a social networking profile, that person is contributing to internet content. Try to imagine one million YouTube users, and each one uploads a one minute video on the same day. In just one day, YouTube would have acquired one million minutes of video content. Without any interruptions (eating, sleeping, etc.), it would take someone almost two years to watch all those videos. Think about that!

All this exchange of content makes people dependent and addicted to internet use. The anguish some people experience when their internet connections fail, or when their cellphones are missing, is evidence of this. GPS devices in cars are great, but, when they do not work properly, many people can find themselves distressingly lost. Texting for some people has become so important that interrupting conversations and work is acceptable and commonplace. When the phone beckons, all must pause for a couple lines of text to be read and then answered. Such behavior would have been considered deplorable in the twentieth century, but nowadays it is rather normal.

For good or bad, the internet is helping extinguish many aspects of life from the last century. One of the most precious things would be free time for deep thinking. The Industrial Revolution made us more productive and efficient so we could have more time to spend on family, hobbies, etc. Now we cannot get enough work-hours to earn all the money we want. And when we are not at work, the internet tempts us with countless new things—videos, articles, games, messages. Sooner or later we have to squeeze in time for sleeping, although not enough for most of us. Where is the time for thinking? For daydreaming, meditating, getting a perspective on our lives? We are losing that time to the internet, much like earlier generations lost it to watching television. When there is time to just sit and think, many of us cannot stand it and languish for access to a computer. Spending time face-to-face with family members and friends is diminishing as well. Video on demand, texting, and other forms of personalized content use eliminate the need for shared experiences. Why watch television with your family when you can watch your shows any time you want on the internet. You no longer have to be in the same room with someone for conversation if you can text or video-conference with them. MP3 players make listening to radios and jukeboxes unnecessary.

What will future internet users be like? Without self-restraint, they will be even more impatient and easily distracted than today. Their writing will be painfully concise. Perhaps the average book's word count will go down. Textbooks, or curricula in general, will be customized excerpts from the online collection of all human knowledge. Nearly all of people's education will come from the internet, not parents and teachers. They will appear to live in separate worlds from an external observer. As they navigate physical environments, earphones let them listen to anything they want. Tiny screens let them see anything they want. And the internet gives them any information they might need in daily tasks. Using the internet as a second brain, they will appear much more knowledgeable and capable than us. They will be more productive because of their connection to cyberspace, but this augmentation will come at a cost. Future users will feel anxious whenever they are disconnected. Sleep deprivation will be a major health concern. The physical world will seem less real than the digital one. Take the internet away, and its users might struggle to cope even with mundane situations. With the internet, they may eventually seem omniscient.

Too much internet use reduces our ability to concentrate, and its distractions hinder the learning process. Depending on your point of view, that is okay because the internet holds more information than we could ever hope to absorb. We just need to make sure that relevant information is available whenever it is needed. Some old-fashioned moderation would protect our mental focus from significantly deteriorating. If we take the time to contemplate what we learn once in a while, then our brains should experience intellectual prosperity. So far we have seen a net benefit from the internet, and, hopefully, we will continue to adapt to our technologies without losing ourselves in the process.