Title: Not–quite–primordial black holesAbstract: In this talk, I will discuss a new mechanism for the formation of seeds of supermassive black holes at early cosmic epochs. Enhanced density fluctuations with amplitudes that are not large enough to form primordial black holes post-inflation can still lead to collapsed dark matter halos at very early times. For halos forming prior to 1+z ~ 200, the Cosmic Microwave Background (CMB) … Read More

Title: On the Run from the Dark Side of the Muon Abstract: In a high-energy muon collider, the beam emits collinear particles that act as partons within the muon with parton distribution functions. I will present a method to search for new physics by exploiting deviations in Standard Model parton distribution functions due to modifying their scale evolution. One can simply select … Read More

Talk title: Higher Axions Abstract: A large fraction of the experimental efforts searching for the (QCD) axion focus on smaller-scale, time-intensive, resonant searches. These searches would greatly benefit from a precise estimate of the axion mass. In theory, the axion mass can be inferred from the observed dark matter abundance and numerical simulations point towards an axion mass (slightly) higher … Read More

Title: Mapping the string axiverse Abstract: Considerable progress has recently been made in understanding the string axiverse in Calabi–Yau compactifications. In this talk I discuss how this axiverse elucidates the quantum gravity prior on axion effective theories and advocate for a modular approach which organizes axiverse statistics around topology. This is illustrated through a study of fuzzy axion dark matter, … Read More

Title: Speedup of Wave-Like Dark Matter Searches Using Entangled Qubits Abstract: Quantum sensing provides novel techniques that can accelerate searches for dark matter (DM). Recent proposals use entangled GHZ states for wave-like DM sensing, where quadratic scaling of the signal can be achieved through coherent addition of amplitudes from each qubit. In this talk, I will show that unlike analogous schemes in … Read More

Title: Spinning up structure in the late early universe Abstract: Current and upcoming cosmological service will provide an unprecedented wealth of information about the distribution of matter on (sub)galactic scales.  These scales broadly enter the cosmic horizon between BBN and CMB epochs.  The excellent agreement between BBN and CMB observations of the early universe makes it challenging for physics beyond the standard … Read More

Title: Global Structure of Symmetries in Particle Physics Abstract: As particle physicists we usually think about small fluctuations of fields, but the phenomenology of our theories can depend crucially on the global structure of the field space. First I’ll discuss an ambiguity in the Standard Model gauge group, whose different versions make different model-independent predictions for the existence of fractionally … Read More

Title: Light Boson Dark Matter & Nonlinear Plasma Dynamics Abstract: Light boson dark matter, such as dark photons and axions, can resonantly convert into electromagnetic excitations in astrophysical and cosmological plasmas, providing powerful probes of light dark matter. Existing constraints and detection strategies typically assume linear plasma response. In this talk, I discuss how nonlinear plasma dynamics qualitatively modify this picture. … Read More

Title: The Next Phase Transition of the Universe: From Metastable Higgs Vacuum Decay to Broken Color and Charge Abstract: Our universe has already gone through a sequence of dramatic phase transitions—possibly including grand unification, electroweak symmetry breaking, and the QCD transition. However, this sequence may not be over yet. The Standard Model Higgs field may still reside in a metastable vacuum, and … Read More

Title: Electroweak Symmetry Restoration at High Energies Abstract: With the milestone discovery of the Higgs boson at the LHC, detailed study of its properties becomes a high priority for collider physics. After a brief overview of the properties of the longitudinal gauge bosons and the Higgs boson, we revisit the Goldstone boson equivalence theorem and define the “electroweak symmetry restoration” (EWSR) … Read More