BEGIN:VCALENDAR VERSION:2.0 CALSCALE:GREGORIAN PRODID:iCalendar-Ruby BEGIN:VEVENT CATEGORIES:Lectures & Presentations DESCRIPTION:The Physics & Astronomy Colloquium Series presents Jianjun Dong of Auburn University\, discussing "Unifying Heat Conduction Across Time an d Length Scales: A Time-Domain Approach to Transient Heat Conduction" on Ja nuary 31.\n\n \n\nAbstract: Understanding ultrafast and nanoscale heat cond uction is crucial for advancing thermal management in nanotechnology. Tradi tional approaches\, such as Fourier's law and heat diffusion equation\, fai l to capture the non-diffusive behavior observed at these scales.\n\n \n\nT his talk introduces a time-domain theoretical framework based on Zwanzig’s statistical theory of irreversible processes\, bridging macroscopic transpo rt equations with microscopic material properties. Central to this theory i s the time-domain transport function\, which captures equilibrium time-corr elation functions of heat fluxes and generalizes the concept of transport c oefficients\, such as thermal conductivity.\n\n \n\nA key outcome of this f ramework is that heat conduction is no longer equivalent to heat diffusion. Instead\, conduction encompasses both onset wave dynamics and long-time di ffusion dynamics\, with the transition governed by the decay timescale of t he transport functions. This approach provides a seamless description of he at conduction\, from wave-like second sound propagation to Fourier diffusio n\, while avoiding mesoscopic constructs like phonon drift velocity in conv entional phonon hydrodynamics.\n\n \n\nThe theory also offers a robust foun dation for interpreting transient thermal techniques\, such as time-domain thermoreflectance (TDTR)\, and modeling heat dissipation in advanced materi als. By integrating atomistic insights with continuum-scale equations\, thi s framework enables the design of materials and interfaces with optimized t hermal properties\, paving the way for breakthroughs in nanotechnology and energy systems. DTEND:20250131T220000Z DTSTAMP:20250223T231953Z DTSTART:20250131T211000Z GEO:39.322732;-82.10287 LOCATION:Walter Hall\, 145 SEQUENCE:0 SUMMARY:Physics Colloquium | Unifying Heat Conduction Across Time and Lengt h Scales: A Time-Domain Approach to Transient Heat Conduction\, Jan 31 UID:tag:localist.com\,2008:EventInstance_48710019163307 URL:https://calendar.ohio.edu/event/physics-colloquium-atomic-jan-31 END:VEVENT END:VCALENDAR