Table of Contents Author Guidelines Submit a Manuscript
Letter to the Editor
Research Article
Advances in High Energy Physics
Volume 2017, Article ID 1683075, 4 pages
Letter to the Editor

Response to: Comment on “Does the Equivalence between Gravitational Mass and Energy Survive for a Composite Quantum Body?”

1Department of Physics, University of Arizona, 1118 E. 4th Street, Tucson, AZ 85721, USA
2L. D. Landau Institute for Theoretical Physics, 2 Kosygina Street, Moscow 117334, Russia

Correspondence should be addressed to A. G. Lebed; ude.anozira.scisyhp@debel

Received 28 February 2017; Accepted 31 May 2017; Published 10 October 2017

Academic Editor: Shi-Hai Dong

Copyright © 2017 A. G. Lebed. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The publication of this article was funded by SCOAP3.


We have recently shown that both passive and active gravitational masses of a composite body are not equivalent to its energy due to some quantum effects. We have also suggested idealized and more realistic experiments to detect the above-mentioned inequivalence for a passive gravitational mass. The suggested idealized effect is as follows. A spacecraft moves protons of a macroscopic ensemble of hydrogen atoms with constant velocity in the Earth’s gravitational field. Due to nonhomogeneous squeezing of space by the field, electron ground state wave function experiences time-dependent perturbation in each hydrogen atom. This perturbation results in the appearance of a finite probability for an electron to be excited at higher energy levels and to emit a photon. The experimental task is to detect such photons from the ensemble of the atoms. More realistic variants of such experiment can be realized in solid crystals and nuclei, as first mentioned by us. In his recent comment on our paper, Crowell has argued that the effect, suggested by us, contradicts the existing experiments and, in particular, astronomic data. We show here that this conclusion is incorrect and based on the so-called “free fall” experiments, where our effect does not have to be observed.