At the start of the nineteenth century, only gas and oil lamps were to be found in homes and businesses, communications took the form of handwritten letters that took days to travel across the country, and several weeks across oceans. But by the end of the century electric light bulbs were common. By 1865, a telegraph cable connected the United States and England....

Have you ever imagined a world without transistors ? Yes ? Then you are in for a major surprise. When you wake up in the morning, what are some of the first things you do? You probably check your phone, and maybe turn on the toaster? Well, both of those are out of the picture in a world without transistors. You’d have to make your toast the old fashion way, telephones would all....

In theoretical physics,negative mass is a matter whose mass is of opposite sign to the mass of normal matter. Such matter would violate one or more energy conditions and show some strange properties.It is used in certain speculative theories,such as on the construction of wormholes. Originally the closest known real representative of such matter is a region....