The quantum nature of gravity remains an open question in fundamental physics, lacking experimental verification. Gravitational waves (GWs) provide a potential avenue for detecting gravitons, the hypothetical quantum carriers of gravity. However, by analogy with quantum optics, distinguishing gravitons from classical GWs requires the preservation of quantum coherence, which may be lost due to...
Aiming to explore quantum gravity, low-energy experiments have been proposed to test whether Newtonian gravity can generate quantum entanglement or not. However, the weakness of gravity hinders experimental realization. In this talk, we propose a novel optimal method to probe gravity-induced entanglement. We consider the gravitational interaction between a particle trapped in a shallow...
Understanding physical phenomena at the intersection of quantum mechanics and general relativity remains one of the major challenges in modern physics. Among various approaches, experimental tests have been proposed to investigate the dynamics of quantum systems in curved spacetime and to examine the quantum nature of gravity in the low-energy regime. However, most previous studies have...
Can we test the quantum mechanical nature of gravitational fields? Milligram-scale optomechanical experiments present a frontier for bridging quantum mechanics and gravitational physics by aiming to strike a balance between 1) making gravitational couplings of the controlled objects dominant and 2) making the motions of these objects quantum noise dominated. Required systems necessitate...
We establish limitations and bounds on the transmission of quantum states between gravitationally interacting mechanical oscillators under different models of gravity. This provides benchmarks that can enable tests for quantum features of gravity. Our proposal does not require the measurement of gravitationally induced entanglement and only requires final measurements of a single subsystem. We...
The dynamics of quantum systems in indefinite spacetimes—such as superpositions of macroscopically distinct semiclassical geometries—have been studied extensively in the contexts of quantum reference frames and quantum field theory in curved spacetimes. These studies typically assume that quantum states associated with different spacetimes (i) form a complete orthonormal basis and (ii) possess...
We nonperturbatively examine the emission rate of acceleration-induced radiation from a uniformly accelerated gapless qudit-type Unruh-DeWitt detector. We find that the emission rate can be written as Larmor’s formula multiplied by a factor that depends on the detector’s initial state. In particular, certain initial states of integer-spin detectors do not produce radiation. Although the...
I will review some recent progresses in the characterization of the properties of spacetimes with relativistic symmetries deformed at the Planck scale (DSR), relying on the exchange of signals between DSR relativisitc observers.
We present a general framework for understanding the finite-time operation of relativistic quantum thermal machines, focusing on their energy optimization. As an example, we introduce an Otto thermodynamic cycle where the working medium is a qubit Unruh-DeWitt detector interacting with a massless, conformally coupled scalar field in the Hartle-Hawking vacuum of a (2+1)-dimensional BTZ black...
We present an explicit construction of a relativistic quantum computing architecture using a variational quantum circuit approach that is shown to allow for universal quantum computing. The variational quantum circuit consists of tunable single-qubit rotations and entangling gates that are implemented successively. The single qubit rotations are parameterized by the proper time intervals of...
QFT models involving detectors are usually modelled perturbatively out of necessity, however, there are certain situations when non-perturbative methods can be used. When the detector is a finite dimensional qudit, non-perturbative modelling is possible if the detector interacts suddenly and very quickly ($\delta$-switching) or if the detector is degenerate (zero energy gap). When the detector...
