Quantum theory appears to allow some kind of connection between entangled particles, but not enough to send messages. Antony Valentini argues this is a conspiracy: there must be something deeper than quantum, where nonlocality can actually be used to send messages, but it is hidden from view in standard quantum experiments. In this episode of the Quantum Foundations Podcast, Valentini uses Pilot-wave theory to explain the physics of the nonlocal subquantum world. He discusses various ways that the theory could be experimentally tested, by looking for signatures of violations of the Born rule in extreme environments, such as the early universe. He also discusses the radical technological implications of subquantum physics, if we were able to harness it.

Valentini recently released a book for a general audience explaining these ideas, "Beyond the Quantum: A Quest for the Origin and Hidden Meaning of Quantum Mechanics".

What if quantum particles have no gravity? In this episode of the Quantum Foundations Podcast, Professor Gerard Milburn explains how this radical idea could solve open problems in quantum theory and lead towards a theory of quantum gravity. It comes with extreme consequences for quantum measurements; the formation of black holes; and even the beginning of the universe. From a new understanding of Bell experiments to a cosmological arrow of time, find out if dropping gravity from the equation could be the start of transforming the field of quantum science and technology.

If there really is a quantum reality for every possible outcome of a measurement, then where do measurement probabilities come from? Dr Tony Short at the University of Bristol has used a set of intuitive assumptions to derive probability in a quantum multiverse. In this episode we discuss his motivations for exploring the many-worlds interpretation; what his assumptions are and how they lead to the Born rule for measurement probabilities; and how these ideas fit within the broader landscape of research in quantum foundations, probability and the many-worlds interpretation.