Alternatives to general relativity

Alternatives to general relativity are <a href="/facts/Physical_theory/Cs2Y12rQ">physical theories</a> that attempt to describe the phenomenon of <a href="/facts/Gravitation/bqAN7DdQ">gravitation</a> in competition with <a href="/facts/Albert_Einstein/CNTet8qu">Einstein's</a> theory of <a href="/facts/General_relativity/jVsoIg8X">general relativity</a>. There have been many different attempts at constructing an ideal theory of <a href="/facts/Gravity/bqAN7DdQ">gravity</a>. These attempts can be split into four broad categories based on their scope:

<ol><li>Classical theories of gravity, which do not involve quantum mechanics or force unification.</li>
<li>Theories using the principles of <a href="/facts/Quantum_mechanics/BRc3Mzgr">quantum mechanics</a> resulting in <a href="/facts/Quantum_gravity/t7whBMNE">quantized gravity</a>.</li>
<li>Theories which attempt to explain gravity and other forces at the same time; these are known as <a href="/facts/Classical_unified_field_theories/ALLCtaE7">classical unified field theories</a>.</li>
<li>Theories which attempt to both put gravity in quantum mechanical terms and unify forces; these are called <a href="/facts/Theory_of_everything/rpossh4t">theories of everything</a>.</li></ol>
None of these alternatives to general relativity have gained wide acceptance. 
General relativity has withstood many <a href="/facts/Tests_of_general_relativity/yDgwtNrw">tests</a> over a large range of mass and size scales. When applied to interpret astronomical observations, cosmological models based on general relativity introduce two components to the universe, <a href="/facts/Dark_matter/y5HgX55N">dark matter</a> and <a href="/facts/Dark_energy/6bWIYewA">dark energy</a>, the nature of which is currently an <a href="/facts/List_of_unsolved_problems_in_physics/vJ3d1A83">unsolved problem in physics</a>. The many successful, high precision predictions of the <a href="/facts/Lambda-CDM_model/DmlhJHQU">standard model of cosmology</a> has lead astrophysicists to conclude it and thus general relativity will be the basis for future progress. However, dark matter is not supported by the <a href="/facts/Standard_model_of_particle_physics/LhVGf9ow">standard model of particle physics</a>, physical models for dark energy do not match cosmological data, and some cosmological observations are inconsistent. These issues have lead to the study of 
alternative theories of gravity.

Alternatives to general relativity open-in-new

Alternatives to general relativity