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The dipolar zero-modes of Einstein action: An informal summary with some new issues

G. Modanese
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Abstract

We recall the main features of metric vacuum fluctuations which have the global property int d^4x sqrt{g(x)} R(x) = 0, even though R(x) does not vanish locally. We stress that these fluctuations could mediate an anomalous coupling between the gravitational field and coherent matter. Some new issues are discussed: (1) these fluctuations still imply that =0; (2) they are not extrema of the action; (3) for finite duration, their volume in phase space is not zero; (4) vacuum fluctuations of this kind are not allowed in QED; (5) their null-action property is a nonperturbative feature; (6) any -real- pure e.m. field generates zero-modes of this kind, too, up to terms of order G^2.

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G. Modanese. 2000-11-08. The dipolar zero-modes of Einstein action: An informal summary with some new issues. https://arxiv.org/abs/gr-qc/0011030

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