Events at Physics |
Events During the Week of May 12th through May 19th, 2024
Sunday, May 12th, 2024
- Academic Calendar
- Graduate School Spring 2024: Doctoral degree deadline
- Time: 11:55 pm - 12:55 am
- Abstract: Degree candidates must complete all steps: CONTACT: 262-2433, gsacserv@grad.wisc.edu
Monday, May 13th, 2024
- Academic Calendar
- Spring Semester Grading deadline
- Abstract: *Note: actual end time may vary.* URL:
- Academic Calendar
- Graduate School Summer 2024: Summer Degree Window Period begins
- Abstract: CONTACT: 262-2433, gsacserv@grad.wisc.edu
Tuesday, May 14th, 2024
- No events scheduled
Wednesday, May 15th, 2024
- Preliminary Exam
- The Physical Characteristics of Faint, High-redshift Dusty Star-forming Galaxies
- Time: 2:00 pm - 4:00 pm
- Place: Sterling Hall, Room B343
- Speaker: Stephen McKay, Physics PhD Graduate Student
- Abstract: Once entirely undetected in large galaxy surveys, dusty star-forming galaxies (DSFGs)--a population of massive, dust-enshrouded galaxies with prodigious star formation rates (SFRs)--contribute heavily to the cosmic star formation history at high redshifts (z ≳ 1). However, since their original detection nearly three decades ago as submillimeter galaxies (or SMGs), a detailed understanding of these galaxies has been extremely difficult to obtain for large samples, in particular for faint sources that fall below typical wide-field survey limits. In this talk, I will discuss my work on inferring the multiwavelength properties of large samples of high-redshift DSFGs using observations with the Atacama Large Millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope (JWST). I will describe how my work will shed light on crucial characteristics of the faint DSFG population, including their dust content, stellar populations, ongoing star formation, molecular gas, and, ultimately, their obscured contribution to the Universe's star formation history across cosmic time.
- Host: Amy Barger, Vernon Barger
- Department Coffee Hour
- Physics Cookie Potluck
- Time: 2:00 pm - 3:00 pm
- Place: University Ave steps or (in case of bad weather) 2120 CH
- Abstract: Let’s celebrate the end of the semester and kick off the summer with a cookie potluck! Bakers should bring a batch of their best to share! If you’re not a baker or don’t have time, just come hang out with us for a bit to have a cookie or two (we always have plenty!). For the bakers, it’d be helpful if you can mark your goodies with an allergens list (especially helpful to mark nuts/no nuts, dairy-free, gluten-free, etc.). If the weather’s nice, let’s gather outside on the front steps (overlooking University Ave). If it’s not so nice, look for us in 2120 CH.
Thursday, May 16th, 2024
- R. G. Herb Condensed Matter Seminar
- Joynt Fest
- Time: 9:00 am - 6:00 pm
- Place: 2241 Chamberlin Hall
- Speaker: Invited Speakers
- Abstract: Program will be updated soon
- Host: Alex Levchenko
- Thesis Defense
- Axionic Blue Isocurvature Perturbations: Generation and Forecast
- Time: 12:00 pm - 2:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Sai Chaitanya Tadepalli, Physics PhD Graduate Student
- Abstract: When additional degrees of freedom are considered during inflation, a crucial aspect of early-universe physics emerges: the generation of isocurvature quantum fluctuations, akin to independent quantum perturbations. These fluctuations can offer valuable insights into inflation and the presence of spectator fields and their mass scales. Current data tightly constrains the cold dark matter (CDM) isocurvature amplitude on scales k<0.1 h/Mpc. However, blue-tilted (spectral index >1) isocurvatures can be invisible on large scales and leave a huge imprint on small scales. This thesis explores the generation and forecast of axionic blue-tilted isocurvature perturbations.
In the first part of this thesis, we study the generation of CDM uncorrelated blue-tilted isocurvature perturbations for the axions when the axionic sector is far out of equilibrium during inflation through an initial Peccei-Quinn symmetry breaking field displacement. We investigate two distinct models, where these fluctuations originate from the dynamical evolution of the radial field through the quadratic and quartic components of the effective potentials. In the quadratic case, we find that there exist parametric regions with a strong resonant spectral behavior that leads to rich isocurvature spectral shapes. A consequence of this nonlinearity-driven resonance is the chaotic nature of the map that links the underlying Lagrangian parameters to the isocurvature amplitudes. In the quartic scenario, we propose a novel method to generate the blue-tilted spectrum over a large range of scales by utilizing the classical conformal limit.
In the second part of the thesis, we present a Fisher forecast for the Euclid and MegaMapper experiments in their ability to detect blue isocurvature perturbations. We construct the theoretical predictions in the EFTofLSS and bias formalisms and report optimistic results highlighting the potential for detecting the CDM blue isocurvature amplitude in forthcoming surveys. - Host: Daniel J Chung
Friday, May 17th, 2024
- No events scheduled
Saturday, May 18th, 2024
- No events scheduled
Sunday, May 19th, 2024
- Academic Calendar
- Faculty contract year ends
- Abstract: *Note: actual end time may vary.* URL: