Classical unified field theories to isospin rather than electromagnetism; this is related to a discrete (or ""internal"") symmetry known to Einstein as "displacement field duality". Einstein became increasingly isolated in his research on a generalized theory of gravitation, and most physicists consider his attempts ultimately unsuccessful. In particular, his pursuit of a unification of the fundamental forces ignored developments in quantum physics (and vice versa), most notably the discovery of the strong nuclear force and weak nuclear force. Inspired by Einstein's approach to a unified field theory and Eddington's idea of the affine connection as the sole basis for differential geometric structure for space-time,
Unified voicemail Unified voicemail Unified voicemail is the combination of different voicemail bearers into a single voicemail system. Using dedicated DID /DDI numbers for each mailbox, the mailbox can be used on a variety of devices and end-points. This is similar to what GSM providers use for their voicemail systems. Mobile phones and traditional analog phones need to support conditional call diversion to enjoy unified voicemail. Unified voicemail can be extended into unified messaging as already used. Some telephone users have several telephone accounts, which may include home, work, mobile, and SIP numbers. Unified voicemail provides a single voicemail for several accounts.