Two roads to the null energy condition

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The null energy condition has sweeping consequences in general relativity. I argue here that it has been misunderstood as a property exclusively of matter, when in fact it arises only in a theory of both matter and gravity. I then derive an equivalent geometric formulation of the null energy condition from worldsheet string theory, where it arises beautifully as simple Einstein's equations in two dimensions. But further, I show that this condition also has a thermodynamic origin, following from a local version of the second law of thermodynamics, applied to gravitational entropy. Thus, far from being an incidental property of matter, the validity of the null energy condition hints at the deep dual origins of gravity.

Original languageEnglish (US)
Article number1544030
JournalInternational Journal of Modern Physics D
Volume24
Issue number12
DOIs
StatePublished - Oct 1 2015

Fingerprint

roads
Null
road
thermodynamics
Energy
gravity
energy
Gravity
gravitation
Second Law of Thermodynamics
Sweeping
entropy
Einstein Equations
String Theory
Einstein equations
General Relativity
string theory
relativity
Two Dimensions
Thermodynamics

Keywords

  • black hole thermodynamics
  • Energy conditions
  • gravitational aspects of string theory

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science
  • Mathematical Physics

Cite this

Two roads to the null energy condition. / Parikh, Maulik.

In: International Journal of Modern Physics D, Vol. 24, No. 12, 1544030, 01.10.2015.

Research output: Contribution to journalArticle

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