Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

the computer business. Instead of etching transistors, engineers etch tiny mechanical components, creating machine parts so small you need a microscope to see them.
    Scientists have made an atomic version of the abacus, the venerable Asian calculating device, that consists of several vertical columns of wires containing wooden beads. In 2000, scientists at the IBM Zurich Research Laboratory made an atomic version of the abacus by manipulating individual atoms with a scanning microscope. Instead of wooden beads thatmove up and down the vertical wires, the atomic abacus used buckyballs, which are carbon atoms arranged to form a molecule shaped like a soccer ball, 5,000 times smaller than the width of a human hair.
    At Cornell, scientists have even created an atomic guitar. It has six strings, each string just 100 atoms wide. Laid end to end, twenty of these guitars would fit inside a human hair. The guitar is real, with real strings that can be plucked (although the frequency of this atomic guitar is much too high to be heard by the human ear).
    But the most widespread practical application of this technology is in air bags, which contain tiny MEM accelerometers that can detect the sudden braking of your car. The MEM accelerometer consists of a microscopic ball attached to a spring or lever. When you slam on the brakes, the sudden deceleration jolts the ball, whose movement creates a tiny electrical charge. This charge then triggers a chemical explosion that releases large amounts of nitrogen gas within 1/25 of a second. Already, this technology has saved thousands of lives.

NEAR TERM (PRESENT TO 2030)
    NANOMACHINES IN OUR BODIES
    In the near future, we should expect a new variety of nanodevices that may revolutionize medicine, such as nanomachines coursing throughout the bloodstream. In the movie
Fantastic Voyage,
a crew of scientists and their ship are miniaturized to the size of a red blood cell. They then embark on a voyage through the bloodstream and brain of a patient, encountering a series of harrowing dangers within the body. One goal of nanotechnology is to create molecular hunters that will zoom in on cancer cells and destroy them cleanly, leaving normal cells intact. Science fiction writers have long dreamed about molecular search-and-destroy craft floating in the blood, constantly on the lookout for cancer cells. But critics once considered this to be impossible, an idle dream of fiction writers.
    Part of this dream is being realized today. In 1992, Jerome Schentag of the University at Buffalo invented the smart pill, which we mentioned earlier, a tiny instrument the size of a pill that you swallow and that can be tracked electronically. It can then be instructed to deliver medicines to the proper location. Smart pills have been built that contain TV camerasto photograph your insides as they go down your stomach and intestines. Magnets can be used to guide them. In this way, the device can search for tumors and polyps. In the future, it may be possible to perform minor surgery via these smart pills, removing any abnormalities and doing biopsies from the inside, without cutting the skin.
    A much smaller device is the nanoparticle, a molecule that can deliver cancer-fighting drugs to a specific target, which might revolutionize the treatment of cancer. These nanoparticles can be compared to a molecular smart bomb, designed to hit a specific target with a chemical payload, vastly reducing collateral damage in the process. While a dumb bomb hits everything, including healthy cells, smart bombs are selective and home in on just the cancer cells.
    Anyone who has experienced the horrific side effects of chemotherapy will understand the vast potential of these nanoparticles to reduce human suffering. Chemotherapy works by bathing the entire body with deadly toxins, killing cancer cells slightly more efficiently than ordinary cells. The collateral damage from chemotherapy is widespread. The side effects—including nausea, loss of hair, loss of strength, etc.—are so severe that some cancer patients would rather die of cancer than subject themselves to this torture.
    Nanoparticles may change all this. Medicines, such as chemotherapy drugs, will be placed inside a molecule shaped like a capsule. The nanoparticle is then allowed to circulate in the bloodstream, until it finds a particular destination, where it releases its medicine.
    The key to these nanoparticles is their size: between 10 to 100 nanometers, too big