Lene Hau. Lene Vestergaard Hau (born November 13, 1959 in Vejle, Denmark) is a Danish physicist. In 1999, she led a Harvard University team who, by use of a Bose-Einstein condensate, succeeded in slowing a beam of light to about 17 metres per second, and, in 2001, was able to stop a beam completely.
Zeta is the sixth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 7. It was derived from the Phoenician letter zayin. Letters that arose from zeta include the Roman Z and Cyrillic Ð.
Also found in: Dictionary, Thesaurus, Legal, Encyclopedia, Wikipedia. zeÂ·ta poÂ·tenÂ·tial. the degree of negative charge on the surface of a red blood cell; that is, the potential difference between the negative charges on the red cell and the cation in the fluid portion of the blood. zeta potential.