If I went back in time and showed Edison a movie on a DVD, would he ever be able to figure out how it worked? How many specific things would he have to invent along the way, in order to arrive at DVD technology?
How much help would it be to him, just to know that the end-product *can *be made?
At the very least, he would have to know about lasers (solid state ones, not the low-tech ones from the 60s), microprocessors, integrated circuits, plastic, transistors, binary math, digital-analog converters, NTSC/PAL video standards, audio standards, LCD displays, LEDs, signals theory, optics, photovoltaics, fiber optics, etc. And that’s just for the player. For a CRT television to display the movie, you’d need to learn about electron guns, luminescent phosphors, vacuum tubes, big capacitors, alternating current (Mr. Edison learned some valuable lessons about that stuff later on.)
The amount of technology that goes into modern electronics is truly staggering. That’s why there aren’t people like Edison anymore to invent things; it took hundreds of engineers to build the first DVD player, because the amount of knowledge required to do so is so immense.
Edison also wasn’t much of an engineer. Edison basically tried lots of crap until he found something that worked, instead of sitting down with pencil and paper and figuring it out beforehand. Mind you, Edison’s method does have it’s merits. If the Generally Accepted Theory is flat out wrong, then working it out on paper beforehand isn’t going to help you.
Finally, Edison wasn’t a lone inventor working out of his gargage (though he did cultivate that image). He had a large staff of people working under him, who would basically take an idea that Edison had, and try to make something with it. Edison got the patents for this because as a condition of their employment, his underlings had to sign over any potential patent rights to him.