Video encyclopedia

Flashback calendar

German biophysicist Erwin Neher is born

His main interest is the cell physiology. Together with Bert Sakmann, Neher was first to record the currents of single ion channels on a live cell. Ion channels are pore-forming proteins in the cell membrane which allow ions to pass. Neher and Sakmann developed special laboratory technique called patch clamp.

General relativity

German physicist Albert Einstein publishes his general theory of relativity in academic journal Annalen der Physik. General relativity describes gravity as a geometric property of space and time, unified into single four-dimensional continuum called space-time. It is more precise than old description of gravity by Isaac Newton.

American psychologist B. F. Skinner is born

He is known as a proponent of behaviorism – often condemned school of thought in psychology. The behaviorists assumed that all behaviors are reflexes produced by a response to certain stimuli in the environment or consequence of that individual's history, especially reinforcements and punishments. Free will is an illusion for them.

Electrical battery

An electric battery is a device consisting of one or more electrochemical cells with external connections provided to power electrical devices such as flashlights, smartphones, and electric cars. When a battery is supplying electric power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that when connected to an external circuit will flow and deliver energy to an external device. When a battery is connected to an external circuit, electrolytes are able to move as ions within, allowing the chemical reactions to be completed at the separate terminals and so deliver energy to the external circuit. It is the movement of those ions within the battery which allows current to flow out of the battery to perform work. Historically the term "battery" specifically referred to a device composed of multiple cells, however the usage has evolved additionally to include devices composed of a single cell.

Anniversaries of the (in)famous