An international research team that included scientists from the University of Regensburg, Germany, scientists from Berkeley and Yale University, USA, Cambridge, UK, and Tsukuba, Japan, measured a very strange effect occurring in a medium of a relatively new type of semiconductor material. According to the results, some electrons in this material behave as if they have a negative mass.
Note that many things in the world around us are characterized only by positive values. Until recently, the mass or weight of a physical object was also a positive quantity, which was one of the unsolved mysteries of modern physics. However, there are many things in nature with negative values of some of their characteristics, and what would happen if the mass of an object could also become a negative value?
According to the laws of Newtonian mechanics, the force applied to an object is equal to the value of its mass multiplied by the acceleration of motion (F=m*a). In other words, if a force is applied to an object, it begins to move with acceleration. However, if you try to kick a stone with negative mass, you should be careful; that stone will fly backward. Similarly, a golf ball with negative mass, once in the water, will not be braked by the resistance of the water, but instead will move with acceleration.
Basically, all of these laws apply at the atomic level as well. We know that the mass of an atom of an element is determined in large part by the mass of the nucleus of that atom, the sum of the masses of all the protons and neutrons in the nucleus. The effective mass of the third component of the atom, the electrons, depends largely on the properties of the electronic material in which these electrons move.
When an electron moves in a material, it constantly collides with other electrons and atomic nuclei. Such collisions cause the electron, which has a positive mass, to slow down and produce a phenomenon known as the electrical resistance of the material. However, if the electron suddenly becomes negative mass, it will lose energy during collisions, accelerating in the process. And it is precisely these effects that scientists were able to observe for the first time in the history of science.
Scientists used a relatively new type of semiconductor material, tungsten diselenide, whose sheet is practically one-atom thick. When this material is illuminated by laser light, it begins to glow, the electrons absorb the photon energy of laser light and, after a short time, emit their own photon of a characteristic red color. The color of the emitted photons corresponds to the fundamental energy of the electron in the semiconductor, which should always shine only red.
However, scientists were able to observe a surprising effect; when tungsten diselenide was irradiated with a red laser, the material’s electrons emitted not only red light, but also a higher-energy blue light. As further studies showed, the low-energy red photons were converted into high-energy blue photons through an extraordinary effect.
By performing spectral analysis, the scientists concluded that the sources of blue light photons were precisely electrons with negative mass. And such an unexpected experimental discovery can be confirmed in the future by a special electronic device with elements similar to those now used in quantum computing technology.
At the moment, this discovery still looks like something unbelievable; nevertheless, scientists have already managed to think of several areas of its practical application. For example, the negative mass effect of electrons can be used to create superfast computers, in circuits in which electrons will move without encountering resistance. Scientists are also very interested in the moment of electron transition from positive mass to negative mass and vice versa. This moment is somewhat related to the attempt to divide a number by zero or to the concept of a black hole in modern cosmology. Nevertheless, at the moments of such transitions very exotic phenomena may occur, which can be put at the service of all mankind in the future.
