Theory of everything differ both from gravity and from electromagnetism. A further hurdle was the acceptance that in a TOE, quantum mechanics had to be incorporated from the start, rather than emerging as a consequence of a deterministic unified theory, as Einstein had hoped. Gravity and electromagnetism could always peacefully coexist as entries in a list of classical forces, but for many years it seemed that gravity could not even be incorporated into the quantum framework, let alone unified with the other fundamental forces. For this reason, work on unification, for much of the twentieth century, focused on understanding the three "quantum" forces:
Unified budget Unified budget In the United States a unified budget is a federal government budget in which receipts and outlays from federal funds and the Social Security Trust Fund are consolidated. The change to a unified budget resulted in a single measure of the fiscal status of the government, based on the sum of all government activity. When these fund groups are consolidated to display budget totals, transactions that are outlays of one fund group (i.e., interfund transactions) are deducted to avoid double counting. The United States government adopted a unified budget in the Johnson administration in 1968, beginning with the