journal club on aspects of information, quantum theory, and gravity
25 Mar 2026
Andrew J. Groszek and Charles W. Woffinden
What if every known communication channel were blocked: no radio, no light, no sound? Is physics out of options? In this talk, we’ll argue that it isn’t. We explore an unconventional idea: using gravity itself as a wireless communication channel. By simply moving a mass back and forth, a sender can modulate the local static gravitational field, which a distant receiver can detect using an off-the-shelf gravimeter. Unlike electromagnetic signals, gravity cannot be shielded, screened, or turned off—and that makes it a uniquely “unblockable” carrier of information.
We introduce the basic physics behind gravitational communication, show how it can be analysed as an antenna problem with well-defined data rates, directionality, and noise, and then present an experimental demonstration. Using nothing more exotic than an antiquated elevator and a 1980s gravimeter, we have successfully transmitted a 49-bit gravitational message through a brick wall. While this is not the future of high-bandwidth Wi-Fi, it opens up a surprisingly rich intersection of gravitation, information theory, and experimental ingenuity—and raises the delightful possibility that you really could communicate using gravity.