The heart receives its own supply of blood from a network of arteries, called the coronary arteries. Two major coronary arteries branch off from the aorta near the point where the aorta and the left ventricle meet:
Walton, Ernest Thomas Sinton - Student Encyclopedia (Ages 11 and up) (1903-95), Irish physicist. Born in County Waterford, Ireland, Walton, with Sir John D. Cockcroft, received the 1951 Nobel prize in physics for the development of the first nuclear-particle accelerator.
The theory provided a good description of the spectrum created by the hydrogen atom, but needed to be developed to suit more complicated atoms and molecules. In 1925, Werner Heisenberg formulated a type of quantum mechanics based on matrices. In 1927 he proposed the uncertainty relation, setting limits for how precisely the position and velocity of a particle can be simultaneously determined.