Past Events

Abstract: Low energy collisions between molecules in the atmosphere lead to about 50% of the particles that act as the seeds for cloud droplets. Many of these molecules, and many of the other particles, are the result of human activity. Therefore cloud droplet concentrations have increased over the industrial period. The increase has led to a poorly quantified cooling effect on Earth that has offset perhaps a third of historical warming from greenhouse gases. The CLOUD experiment at CERN is a laboratory facility for the study of atmospheric particle formation.

The Department of Biochemistry invites professors and scientists fr

The power of quantum information lies in its capacity to be nonlocal, encoded in correlations among entangled particles.  By contrast, the interactions between particles are typically local, posing both conceptual and practical challenges in understanding, generating, and harnessing entanglement.  To circumvent this bottleneck, we trap an array of atom clouds in an optical resonator that mediates effectively nonlocal interactions, letting photons act as messengers that convey information between distant sites.

Following in the tradition of other NASA missions like Hubble and the James Webb Space Telescope, the Habitable Worlds Observatory (HWO) is a future NASA FUV-NIR flagship that will revolutionize multiple areas of astrophysics. A challenging next frontier of astronomy and planetary science is to directly image temperate Earth-sized in planets in the habitable zones of Sun-like stars, measure their spectra, and search them for signs of life. HWO will be the first observatory designed to tackle the question “Are we alone?”.

Optical lattice clocks that interrogates N atoms for an interrogation time T can, in principle, reach the quantum-projection-noise (QPN) instability σ_y (τ)∼1/(πν_0 T√Nτ), with ν_0 the clock frequency and τ the averaging time. In practice, however, dead time between preparation and readout aliases the local-oscillator (LO) frequency noise (Dick effect [1]), so the achievable instability is set by the LO noise spectrum and the duty cycle rather than by the QPN limit. This motivates zero-dead-time (ZDT) operation, which removes aliasing by maintaining continuous interrogation.

Almost exactly 100 years ago, in the early months of 1926, Erwin Schrödinger published a series of four papers that would transform not only the prevailing theories of physics but also mankind’s very understanding of the nature of reality.

CU Physics Prof. James Thompson explains how superheroes' understanding of fundamental physics ensures truth and thwarts villains! Sparks, explosions and plenty of action will punctuate this free STEM show that's open to students of all ages.

For over 40 years, CU Wizards presents FREE STEM Saturday morning shows for kids and their families. Visit: www.colorado.edu/cuwizards

For the overwhelming majority of organisms, effective communication and coordination are critical in the quest to survive and reproduce. A better understanding of these processes can benefit from physics, mathematics, and computer science – via the application of concepts like energetic cost, compression (minimization of bits to represent information), and detectability (high signal-to-noise-ratio). My lab's goal is to formulate and test phenomenological theories about natural signal design principles and their emergent spatiotemporal patterns.

Join us to explore the science and engineering behind the light sources that enable advanced semiconductor manufacturing. This lecture connects industrial innovation at ASML and CLS with fundamental physics, highlighting how precision engineering, high‑power lasers, and decades of development shape modern technology.

What really changes when you step outside academia? And what do you wish someone had told you before you made the leap? ASML employees will share candid stories about challenges, trade‑offs, and unexpected wins along the way. We’ll talk openly about professional shifts, visibility, mentorship, and the often-invisible skills that shape careers beyond publications and CVs. Designed as a conversation rather than a lecture, the session leaves plenty of space for questions, reflections, and real dialogue.

Jayson Stewart shares his personal journey from JILA to ASML and what surprised him most about moving from academia into industry. The talk is intentionally light on technical details and focuses on real-world lessons and how life at JILA prepares one for a career with impact. Expect candid reflections, practical advice, and plenty of time for Q&A.​

Abstract: Effective field theories (EFTs) form the basis of our most successful theories of matter, both in particle physics and in condensed matter physics. But the structure of EFTs poses a challenge to many standard philosophical accounts of theory structure and content. In particular, the inability to cast EFTs in terms of exact mathematical objects defined at all scales suggests that philosophical accounts of theory interpretation ought to be modified to deal with approximate, scale-relative ontologies.

Abstract: The mineralogy of our planet is a fingerprint of history—a durable archive of the physical and chemical conditions that have evolved over 4.5 billion years. Minerals record temperatures and pressures, redox states and fluid compositions, preserving evidence that spans the earliest violent collisions of solar-system formation to human activities that occurred only yesterday. Yet Earth’s mineral story reaches far deeper in time, extending back to the very origins of the elements themselves.

The Department of Biochemistry invites professors and scientists from other universities and institutes to present seminars at the University of Colorado Boulder throughout the academic year. These seminars provide an opportunity for faculty and students to learn about exciting current research.

Nuclear spins are usually not thought to participate in chemical reactions. However, in the ultracold temperature regime, we have a new opportunity to examine this general statement with quantum mechanical details. In this talk, I will present our ongoing investigations into the roles of nuclear spins, quantum coherence, and entanglement in molecule-molecule reactions and atom-molecule collisions, utilizing a one-of-a-kind ultracold KRb molecule apparatus inspired from the original set of JILA KRb experiments 17 years ago.

The interaction of the electronic spin and molecular vibrations mediated by spin-orbit coupling governs spin relaxation in molecular qubits. We derive a dynamic molecular spin Hamiltonian that includes both adiabatic and non-adiabatic spin-dependent interactions, and we implement the computation of its matrix elements using density functional theory. The dynamic molecular spin Hamiltonian contains a novel spin-vibronic interaction with non-adiabatic origin in addition to the conventional molecular Zeeman and dipolar spin interactions with adiabatic origin.

The evolutionary history, and likely habitability, of exoplanet atmospheres depends on the space weather of their host stars. Understanding the particle environment, including the wind density, magnetic field strength, and velocity field, impinging on exoplanet systems remains a significant open question. This unknown impacts the interpretation of exoplanet atmosphere observations and the ongoing search for biosignatures, with facilities like JWST.

Synchronization—the spontaneous emergence of phase coherence among interacting oscillators—is a ubiquitous phenomenon in classical systems, from pendulum clocks to biological rhythms. In quantum systems, however, coherence is fragile, and environmental noise is usually viewed as its primary adversary. This colloquium explores a counterintuitive regime in which noise itself becomes a resource, driving rather than destroying coherent behavior.