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Here are some inventions, discoveries or developments that may be coming or should be coming. Some of these are food for thought, some are a bit fanciful, and some are outright predicitons. More and more streets, parks and buildings have video cameras watching over them and the people who use them. Some hosts for cameras are mobile. Police departments are putting cameras into patrol cars. Some are government operated, but most are privately owned. The main use is to provide security. These video cameras also provide a record of what happens, for example in police proceedings. The driving forces seem to be demand for security, better technology and dramatically shrinking prices. The next step could be to integrate the cameras. If we link the cameras' output, presumably using the Internet, and feed the data into a supercomputer complex, all sorts of analysis becomes possible. Someone could ask that supercomputer what a particular person did on a certain day. The supercomputer would search through the video data, locate all images of the desired person, and report back. Is this possible today? Heck no. For one thing, the cameras are not linked. For another, we do not have anywhere near enough computing power to pull this off. But give us several years to develop more powerful massively parallel supercomputers, add more advanced databases with a lot of pre-indexing (sort of like Internet search engines do to allow users to quickly find content in Web sites), and this may be possible. Greg Bear postulates this setup in his novel Queen of Angels. In the novel, society has set up legal safeguards in the form of an agency called Citizen Oversight that must approve requests for the data, so that the analog of a search warent is necessary to search the video records in this manner, which, to some extent, deals with the privacy (or Big Brother) issue. Robert Ludlum shows a scarier version of this possibility in his novel The Prometheus Deception . Ludlum does not handle the technology well, but he shows what could go wrong if these capabilities are misused. An article on related technology, using tiny sensors that are not video cameras, is in Business Week at Tech Wave 2: The Sensor Revolution, though you have to subscribe to Business Week to read it. This is the use of extremely tiny (nano-sized) machines to carry out activities where their small size is an advantage. Medicine is an abvious use if we can make nano machines that are small enough to enter the body. Survelliance is a potential if we can build nano machnes that can communicate and also read radio signals or interpret light (i.e. have a camera). Greg Bear suggests they could be used in war. See for example his novel Moving Mars, where he has nano machines operating in concert with pre-programmed group intelligence, perhaps analogous to the way hive insects, like ants and bees, work. John Barnes uses nano machines in some of his novels (Earth Made of Glass for example) to construct buildings and the like, again assuming some sort of pre-programmed guidance. In practice, we will have to see about much of this. Not only do we have to figure out how to make nano sized machines that are actually useful in some manner, but we have to find a way to provide them with energy and durability. Cheap Cooling / Air Conditioning Air conditioning, the term we use for the technology that we ordinarily use to cool buildings and cars, is expensive. In fact, it is more expensive than heating the same room or vehicle. Intuitively, this does not make sense, though most of us realize that air conditioning is an inefficient process. Why is air conditioning so expensive? We cannot just directly cool the air. When we heat something, we convert some form of energy to heat. We do not waste too much. Almost the opposite, other forms of activity tend to generate waste heat. Look at light bulbs, for example. To cool something, air conditioners compress a liquid, let it expand (which cools it like people cool by evaporating sweat from their bodies, since evaporation is a form of expansion), and pump it into the region we want to cool, where the liquid is warmed by the air that we want to cool, which in turn cools that air. As the process repeats, the air conditioner transfers heat outside the area we are cooling, at the cost of energy to pump and compress the liquid. Note that no "cooling" has been created -- we have just moved heat energy around. By the way, the same applies to refrigerators, too. Contrast this with heating, where we actually make things warmer overall. What exactly does it mean for something to be warmer or cooler? It means that the various molecules that make up the substance (air in your room, meat in your refrigerator) are vibrating, or moving around, faster (warmer) or slower (colder). At the low level of molecules, heat is just speed. A point to note here is that the assorted molecules are moving at different speeds. Something's warmth is the average speed of those molecules. Some molecules will be moving faster and some slower, but, if we lower the average speed, it gets colder. We need a cheap means to lower the average speed of moleclues in an area then, so we can cool it cheaply. We cannot just blast "cold" into the air, like we can do with heat energy. Air conditioners suck heat energy out, as we explained above, but they take too much energy. We need a trick. Here is the trick. We are interested in average energy of these molecules. All we need to do is to remove the fastest (hottest) molecules from our area, and replace them with some slow moving (cool) molecules from the surrounding area. Yes -- we do have to replace them. We are trying to cool things, not create vacuums. If we can make this exchange, then we have cooled one area, in return for making the surrounding area warmer. Air conditioners also move heat around, but at the cost of too much energy. Air conditioners do not employ the trick of just trading fast for slow molecules. To make this trade of molecules moving at different speeds, we use the fact that faster vibrating molecules take up more room, because they are moving around more. However, they all do move. We need a way to get a lot of hot molecules to leave our area and to bring in some slower & cooler molecules. Picture a screen with real tiny holes that work in one direction. In the direction leading out of our area, we have slightly bigger holes that let fast molecules out. In the direction leading in, we have smaller holes, so only slower molecules can enter. Remember, we are looking for averages here. We want hotter molecules on average to leave and colder molecules on average to come in. We do not need all our molecules to go or stay, just a small per cent, so we can feel the difference. This kind of technique is unlikely to be able to achieve absolute zero or to make liquid oxygen -- we just want to cool a room or keep our soft drinks cold. We have to invent some sort of filter to do this. Maybe we can make the filter out of an exotic material. Maybe we can make it out of a magnetic field of some sort. If someone can invent this, it could revolutionize much of the way we live. Yes, this device would be useful for heating, too, by running it in reverse. It seems more relevant for cooling, since the device is likely to require some energy to operate and cooling requires more energy than heating. Here is the joker and problem with this invention-to-be. It could violate the Second Law of Thermodynamics. The Second Law says we cannot get more energy out of a substance than we put in. We could get energy by using the (now) hotter area to, say, make steam from the (now) colder substance, for example. Thus, it should take at least as much energy as we could theoretically extact from the differing temperatures our filter has created in order to operate our filter. This relates to the concept of entropy . Entropy is kind of like a measure of the amount of disorder in the universe. The universe does not want to be organized, or ordered. To order it, such as by putting cold things in one place and hot in another, takes energy. Tbink about it. If we could cool an area using this filter at no energy cost, then use the resulting temperature difference to generate steam and power something, we would have a perpetual energy machine. Not going to happen. But, let's see if we cannot be more efficient at cooling than we currently are. Maybe our filter will use only as much energy as the theoretical minimum, or only a little more. That is a lot better than current air conditioners. Most of us know that eating meat has some real disadvantages. It is not particularly healthy, having a lot of cholesterol and fat, with much of the fat being an unhealthy version of fat, though not as bad as some would claim. Raising meat is economically inefficient. Meat animals, such as cows, pigs and chicken, eat plant food. Instead of just growing the plants and eating them, to get meat, we grow plants, feed the plants to the animals, then eat the animal. This, from a purely economic perspective, wastes a lot of resources. To be more efficient economically, we tend to mistreat the animals, such as by confining them to small areas, or feeding foodstuffs (such as corn) that are not naturally part of their diet to cattle. Note -- some exceptions do exist to these last two principles. For example, ranchers can raise cattle in somewhat arid pasture, where they eat grasses, a natural diet for cows, that would not be suitable for human consumption, on land that does not readily grow alternate crops, typically due to lack of water or poor soil. Still, we raise most meat animals these days using resource-intensive food sources that require lots of water and fertilizer. Nevertheless, we eat meat anyway. Most of us really like meat, even crave it. Meat tends to be an easy source of protein and various other nutrients. Suppose we had a food that tasted as good as meat and was an excellent source of protein, yet was healthy and economically efficient? The way to do this is to invent plants that grow meat on them, perhaps as roots, perhaps as leaves, perhaps as fruits. These plants would produce meat that resembles beef, pork, chicken, buffalo or other meats. We would design the plants to not have cholesterol or unhealthy fats. It seems reasonable that clever genetic engineering could do this. Last Update:06 January 2005 ©2002, 2003, 2004, 2005 HereAndOk. All Rights Reserved. |
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