# The atoms of spacetime and the cosmological constant

@article{Padmanabhan2017TheAO, title={The atoms of spacetime and the cosmological constant}, author={Thanu Padmanabhan}, journal={Journal of Physics: Conference Series}, year={2017}, volume={880} }

I describe an approach which relates classical gravity to the quantum microstructure of spacetime. In this approach, the field equations arise from maximizing the density of states of the matter plus geometry. The former is identified using the thermodynamics of null surfaces. The latter arises from the existence of a zero-point length in the spacetime which associates an internal degree of freedom with each event in the spacetime, in the form of a fluctuating vector of constant norm. The…

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