TY - JOUR
T1 - Variational principle for gravity with null and non-null boundaries
T2 - a unified boundary counter-term
AU - Parattu, Krishnamohan
AU - Chakraborty, Sumanta
AU - Padmanabhan, T.
N1 - Funding Information:
The research of TP is partially supported by J.C.Bose research grant of DST, India. KP and SC are supported by the Shyama Prasad Mukherjee Fellowship from the Council of Scientific and Industrial Research (CSIR), India. KP and SC would like to thank Kinjalk Lochan for discussions.
Publisher Copyright:
© 2016, The Author(s).
PY - 2016/3/1
Y1 - 2016/3/1
N2 - It is common knowledge that the Einstein–Hilbert action does not furnish a well-posed variational principle. The usual solution to this problem is to add an extra boundary term to the action, called a counter-term, so that the variational principle becomes well-posed. When the boundary is spacelike or timelike, the Gibbons–Hawking–York counter-term is the most widely used. For null boundaries, we had proposed a counter-term in a previous paper. In this paper, we extend the previous analysis and propose a counter-term that can be used to eliminate variations of the “off-the-surface” derivatives of the metric on any boundary, regardless of its spacelike, timelike or null nature.
AB - It is common knowledge that the Einstein–Hilbert action does not furnish a well-posed variational principle. The usual solution to this problem is to add an extra boundary term to the action, called a counter-term, so that the variational principle becomes well-posed. When the boundary is spacelike or timelike, the Gibbons–Hawking–York counter-term is the most widely used. For null boundaries, we had proposed a counter-term in a previous paper. In this paper, we extend the previous analysis and propose a counter-term that can be used to eliminate variations of the “off-the-surface” derivatives of the metric on any boundary, regardless of its spacelike, timelike or null nature.
UR - http://www.scopus.com/inward/record.url?scp=84960897678&partnerID=8YFLogxK
U2 - 10.1140/epjc/s10052-016-3979-y
DO - 10.1140/epjc/s10052-016-3979-y
M3 - Article
AN - SCOPUS:84960897678
VL - 76
JO - European Physical Journal C
JF - European Physical Journal C
SN - 1434-6044
IS - 3
M1 - 129
ER -