Unified field theory of (the not mathematically well-defined) quantum electrodynamics. One can extend this system to include the weak and strong nuclear forces to get the Einstein–Yang–Mills–Dirac System. The French physicist Marie-Antoinette Tonnelat published a paper in the early 1940s on the standard commutation relations for the quantized spin-2 field. She continued this work in collaboration with Erwin Schrödinger after World War II. In the 1960s Mendel Sachs proposed a generally covariant field theory that did not require recourse to renormalisation or perturbation theory. In 1965, Tonnelat published a book on the state of research on unified field theories. In 1963 American physicist
Unified communications voice mail from any communication device at any time. It expands beyond voice mail services to data communications and video services. With unified communications, multiple modes of business communications are integrated. Unified communications is not a single product but a collection of elements that includes: "Presence"—knowing where intended recipients are, and if they are available, in real time—is a key component of unified communications. Unified communications integrates all systems a user might already use, and helps those systems work together in real time. For example, unified communications technology could allow a user to seamlessly collaborate with another person on a