  In the current era of high-z galaxy discovery with JWST and ALMA, our ability
to study the stellar populations and ISM conditions in a diverse range of
galaxies at Cosmic Dawn has rapidly improved. At the same time, the need to
understand the current limitations in modeling galaxy formation processes and
physical properties in order to interpret these observations is critical. Here,
we study the challenges in modeling galaxy dust temperatures, both in the
context of forward modeling galaxy spectral properties from a hydrodynamical
simulation and via backwards modeling galaxy physical properties from mock
observations of far-infrared dust emission. Using the Simba model for galaxy
formation combined with Powderday radiative transfer, we can accurately predict
the evolution of dust at high redshift, though several aspects of the model are
essentially free parameters (dust composition, sub-resolution dust in
star-forming regions) that dull the predictive power of the model dust
temperature distributions. We also highlight the uncertainties in the backwards
modeling methods, where we find the commonly used models and assumptions to fit
FIR SEDs and infer dust temperatures (e.g., single temperature, optically thin
modified blackbody) largely fail to capture the complexity of high-z dusty
galaxies. We caution that conclusions inferred from both simulations -- limited
by resolution and post-processing techniques -- and observations -- limited by
sparse data and simplistic model parameterizations -- are susceptible to unique
and nuanced uncertainties that can limit the usefulness of current high-z dust
measurements.
