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

wild card is the fusion machine of Philo Farnsworth, the unsung coinventor of TV. As a child, Farnsworth originally got the idea for TV by thinking of the way a farmer plows his fields, row after row. He even sketched the details of his prototype at the age of fourteen. He was the first to transfer this idea to a fully electronic device capable of capturing moving images on a screen. Unfortunately, he was unable to capitalize on his landmark invention and was mired in lengthy, messy patent fights with RCA. His legal battles even drove him crazy, and he voluntarily checked himself into an insane asylum. His pioneering work on TV went largely unnoticed.
    Later in life, he turned his attention to the fusor, a small tabletop device that can actually generate neutrons via fusion. It consists of two large spheres, one inside the other, each made of a wire mesh. The outer mesh is positively charged, while the inner mesh is negatively charged, so protons injected through this mesh are repelled by the outer mesh and attracted to the inner mesh. The protons then smash into a hydrogen-rich pellet in the middle, creating fusion and a burst of neutrons.
    The design is so simple that even high school students have done what Richter, Pons, and Fleischmann could not do: successfully generate neutrons. However, it is unlikely that this device will ever yield usable energy. The number of protons that are accelerated is extremely small, and hence the energy resulting from this device is very tiny.
    In fact, it is also possible to produce fusion on a tabletop using a standard atom smasher or particle accelerator. An atom smasher is more complicated than a fusor, but it can also be used to accelerate protons so that they can slam into a hydrogen-rich target and create fusion. But again, the number of protons that are fused is so small that this is an impractical device. So both the fusor and atom smasher can attain fusion, but they are simply too inefficient and their beams are too thin to produce usable power.
    Given the enormous stakes, no doubt other enterprising scientists and engineers will have their chance to turn their basement contraptions into the next mega invention.

FAR FUTURE (2070 TO 2100)
    AGE OF MAGNETISM
    The previous century was the age of electricity. Because electrons are so easily manipulated, this has opened up entirely new technologies, making possible radio, TV, computers, lasers, MRI scans, etc. But sometime in this century, it is likely that physicists will find their holy grail: room temperature superconductors. This will usher in an entirely new era, the age of magnetism.
    Imagine riding in a magnetic car, hovering above the ground and traveling at several hundred miles per hour, using almost no fuel. Imagine trains and even people traveling in the air, floating on magnetism.
    We forget that most of the gasoline we use in our cars goes to overcoming friction. In principle, it takes almost no energy to ride from San Francisco to New York City. The main reason this trip consumes hundreds of dollars of gasoline is because you have to overcome the friction of the wheels on the road and the friction of the air. But if you could somehow cover the road from San Francisco to New York with a layer of ice, you could simply coast most of the way almost for free. Likewise, our space probes can soar beyond Pluto with only a few quarts of fuel because they coast through the vacuum of space. In the same way, a magnetic car would float above the ground; you simply blow on the car, and the car begins to move.
    The key to this technology is superconductors. It has been known since 1911 that mercury, when cooled to four degrees (Kelvin) above absolute zero, loses all electrical resistance. This means that superconducting wires have no energy loss whatsoever, since they lack any resistance. (This is because electrons moving through a wire lose energy as they collide with atoms. But at near absolute zero, these atoms are almost at rest, so the electrons can easily slip through them without losing energy.)
    These superconductors have strange but marvelous properties, but one severe disadvantage is that you have to cool them to near absolute zero with liquid hydrogen, which is very expensive.
    Therefore, physicists were in shock in 1986 when it was announced that a new class of superconductors had been found that did not need tobe cooled to these fantastically low temperatures. Unlike previous materials like mercury or lead, these