Revolução na Teoria de Gravitação?

Gravity as an entropic force

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Verlinde's statistical description of gravity as an entropic force leads to the correct inverse square distance law of attraction between classical bodies.

The hypothesis of gravity being an entropic force has a history that goes back to research on black hole thermodynamics by Bekenstein andHawking in the mid-1970s. These studies suggest a deep connection between gravity and thermodynamics. In 1995 Jacobson demonstrated that the Einstein equations describing relativistic gravitation can be derived by combining general thermodynamic considerations with the equivalence principle.^[1] Subsequently, other physicists have further explored the link between gravity and entropy.^[2]

In 2009, Erik Verlinde disclosed a conceptual theory that describes gravity as an entropic force.^[3] This theory combines the thermodynamic approach to gravity with Gerardus 't Hooft's holographic principle. If proven correct, gravity is not a fundamental interaction, but an emergent phenomenon which arises from the statistical behaviour of microscopic degrees of freedom encoded on a holographic screen.^[4]

Verlinde's suggestion of gravity being an entropic phenomenon attracted considerable media^[5][6] exposure, and led to immediate follow-up work in cosmology,^[7][8] the dark energy hypothesis,^[9] cosmological acceleration,^[10][11] cosmological inflation,^[12] and loop quantum gravity.^[13] Also, a specific microscopic model has been proposed that indeed leads to entropic gravity emerging at large scales.^[14]

[edit]See also

• Entropic Spacetime Theory
• Entropic elasticity of an ideal chain
• Entropic force
• Gravitation
• Induced gravity

[edit]References

This article uses bare URLs in its references. Please use proper citations containing each referenced work's title, author, date, and source, so that the article remains verifiable in the future. Help may be available. Several templates are available for formatting. (March 2010)

1. ^ Thermodynamics of Spacetime: The Einstein Equation of State, Ted Jacobson, 1995
2. ^ Thermodynamical Aspects of Gravity: New insights, Thanu Padmanabhan, 2009
3. ^ http://www.volkskrant.nl/wetenschap/article1326775.ece/Is_Einstein_een_beetje_achterhaald Dutch newspaper 'Volkskrant', 9 December 2009
4. ^ On the Origin of Gravity and the Laws of Newton, Erik Verlinde, 2010
5. ^ The entropy force: a new direction for gravity, New Scientist, 20 January 2010, issue 2744
6. ^ Gravity is an entropic form of holographic information, Wired Magazine, 20 January 2010
7. ^ Equipartition of energy and the first law of thermodynamics at the apparent horizon, Fu-Wen Shu, Yungui Gong, 2010
8. ^ Friedmann equations from entropic force, Rong-Gen Cai, Li-Ming Cao, Nobuyoshi Ohta 2010
9. ^ It from Bit: How to get rid of dark energy, Johannes Koelman, 2010
10. ^ Entropic Accelerating Universe, Damien Easson, Paul Frampton, George Smoot, 2010
11. ^ Entropic cosmology: a unified model of inflation and late-time acceleration, Yi-Fu Cai, Jie Liu, Hong Li, 2010
12. ^ Towards a holographic description of inflation and generation of fluctuations from thermodynamics, Yi Wang, 2010
13. ^ Newtonian gravity in loop quantum gravity, Lee Smolin, 2010
14. ^ Notes concerning "On the origin of gravity and the laws of Newton" by E. Verlinde, Jarmo Makela, 2010

[edit]Further reading

• Gravity: the inside story, T Padmanabhan