vaakumi

Vaakumi is the Finnish term for vacuum, describing a region in which the pressure is very low and there is little or no matter remaining. In physics and engineering, vaakumi refers to an environment where gas molecules are sparse, enabling systems to operate without air resistance, condensation, or chemical reactivity from surrounding air. The concept includes both natural space devoid of matter and engineered environments created by removing air.

Vacuum quality is categorized by the achieved pressure: rough vacuum, high vacuum, and ultra-high vacuum, with progressively lower pressures and different practical implications for experiments and manufacturing. Realized vaakumi conditions are achieved with different pumping technologies depending on the required level of emptiness.

Pumps suitable for producing vaakumi range from positive-displacement pumps, which expel gas to create a low-pressure environment, to momentum-transfer pumps, such as turbomolecular and diffusion pumps, which move gas molecules out of the chamber. In ultra-high vacuum, specialized pumps like ion pumps and cryopumps are used. Vacuum systems rely on seals, chamber design, and outgassing control to maintain low pressures. Pressure is measured with gauges, including Pirani or thermocouple gauges for rough vacuum, and ionization gauges for high and ultra-high vacuum.

Applications of vaakumi include electron microscopy, surface science and spectroscopy, semiconductor manufacturing, thin-film coatings, vacuum insulation for buildings and vessels, space simulation, and degassing of sensitive chemical compounds.

Historically, attempts to create vacuum date to early modern science, with Otto von Guericke's air-pump experiments in the 17th century, followed by Torricelli's barometer and Boyle's experiments. In Finnish technical usage, vaakumi remains the standard term for vacuum, with tyhjiö more formal or scientific synonym in some contexts.