arXiv subjects

Thomas Mann

Publications and source records attributed to Thomas Mann.

5 recordsLinked to original sources

arXiv2026

AI Research Preference Models

AI research agents (AIRA) can now carry machine learning experiments from proposal through implementation and evaluation. Yet progress on frontier tasks is throttled by the cost of evaluations that can consume days of GPU time. When an agent can propose far more candidates than it can afford to run, progress depends on its research preference: how it allocates a fixed execution budget across many candidates. We introduce AI Research Preference Models (RPMs) that predict which candidate solution is most promising, without paying the cost of running them all. We build RPMs from frozen pretrained language models in two variants: an inference-only model that reasons over candidate plans, code, and previously executed solutions, and an agentic model that additionally runs small-scale pilot experiments. Integrated into the AIRA-dojo research agent and evaluated on the machine learning research benchmark AIRS-Bench, the two variants increase the average normalized score from 0.684 to 0.711 and 0.729, respectively. Both reach the unguided agent's 24-hour performance in roughly 15 hours, using less than two-thirds of its execution budget, and together yield new state-of-the-art results on two AIRS-Bench tasks.

cs.AI↗

arXiv2023

Mirror-mediated ultralong-range atomic dipole-dipole interactions

In three dimensions, dipole-dipole interactions which alter atomic level shifts and spontaneous decay rates only persist over distances comparable to the wavelength of the emitted light. In this paper we show that it is possible to significantly extend the range of these interactions with the help of a partially transparent asymmetric mirror interface. Suppose two two-level atoms are placed on opposite sides of the interface, each at the position of the mirror image of the other. In this case, their emitted light interferes almost exactly as it would when the atoms are right next to each other. Hence their dipole-dipole interaction assumes an additional maximum, even when the actual distance of the atoms is several orders of magnitude larger than the transition wavelength. Although the resulting ultralong-range interactions are in general relatively weak, we expect them to find applications in quantum technology, like non-invasive quantum sensing.

quant-ph↗

arXiv2021

The quantum optics of asymmetric mirrors with coherent light absorption

The local observables of the quantised electromagnetic field near a mirror-coated interface depend strongly on the properties of the media on {\em both} sides. In macroscopic quantum electrodynamics, this fact is taken into account with the help of optical Green's functions which correlate the position of an observer with all other spatial positions and photon frequencies. Here we present an alternative, more intuitive approach and obtain the local field observables with the help of a quantum mirror image detector method [Furtak-Wells et al., Phys. Rev. A 97, 043827 (2018)]. In order to correctly normalise electric field operators, we demand that spontaneous atomic decay rates simplify to their respective free space values far away from the reflecting surface. Our approach is interesting, since mirror-coated interfaces constitute a common basic building block for quantum photonic devices.

quant-ph↗

arXiv2020

Spontaneous emission of atomic dipoles near two-sided semi-transparent mirrors

Atom-field interactions near optical interfaces have a wide range of applications in quantum technology. Motivated by this, this paper revisits the spontaneous emission of atomic dipoles in the presence of a two sided semi-transparent mirror. First we review the main properties of the quantised electromagnetic field near a semi-transparent mirror. To do so, we employ a quantum mirror image detector method which maps the experimental setup which we consider here onto analogous free space scenarios. We emphasise that the local density of states of the electromagnetic field depends on the reflection rates of both sides of the mirror surface. Hence it is not surprising that also the spontaneous decay rate of an atomic dipole in front of a semi-transparent mirror depends on both reflectance rates. Although the effect which we describe here only holds for relatively short atom-mirror distances, it can aid the design of novel photonics devices.

quant-ph↗

arXiv2014

Higgs Factory and 100 TeV Hadron Collider: Opportunity for a New World Laboratory within a Decade

Suggestions have been made for a 80-100 km circumference Future Circular Collider (FCC) that could ultimately contain a circular e+e- ring collider operating as a Higgs Factory as well as a 100 TeV hadron collider. Those suggestions have motivated us to propose an approach in which the project is sited at the location at the SSC tunnel, which has the lowest tunnel cost ever. The low tunnel cost would make it cost-effective to locate the 100 TeV Hadron Collider in a 270 km circumference tunne, using 4.5 Tesla superconducting magnets. The SSC tunnel itself would be used to house the Higgs Factory and the injector for the Hadron Collider. The injector for the Higgs Factory would be also used as a driver for an X-ray Free Electron Laser with unique capabilities for protein crystallography. The location of the project at a location with favorable geotechnology for minimum-cost tunneling, and low-cost/low-risk technology for the SRF and superconducting magnets, open the possibility to build the proposed laboratory within a decade.

physics.acc-ph↗