Unification of Forces : There have been physicists who have tried to combine a few of the above fundamental forces . These are listed in table below .
Name of Physicist |
Year |
Achievement in Unification |
Isaac Newton |
1687 |
Unified celestial and terrestrial mechanics . |
Hans Christian Oersted and Michael Faraday
1820 and 1830 Unified electric and magnetic phenomena respectively to give rise to electromagnetism .
James Clerk Maxwell 1873
Unified electricity , magnetism and optics to show that light is an electromagnetic wave .
Sheldon Glashow , Abdus Salam , Steven Weinberg
Carlo Rubia , Simon Vander Meer
1979
1984
Gave the idea of electro-weak force which is a combination of electromagnetic and weak nuclear force .
Verified the theory of elctro-weak force .
Conserved Quantities
Physics gives laws to summarize the investigations and observations of the phenomena occurring in the universe .
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Physical quantities that remain constant with time are called conserved quantities . Example , for a body under external force , the kinetic and potential energy change over time but the total mechanical energy ( kinetic + potential ) remains constant .
Conserved quantities can be scalar ( Energy ) or vector ( Total linear momentum and total angular momentum ).