Podcast appearances and mentions of David W Hogg

When gazing into the deep expanse of the universe and finding the distant quasars and galaxies, we notice a particular feature that is commonplace no matter where we look: the further away the galaxy or deep sky object is, the redder, or the longer wavelength, the object appears; it seems that a galaxy like the Andromeda Galaxy is far less red than a comparable galaxy that is 1.6 billion light years away. This feature was once noticed by the astrophysicist Edwin Hubble, a physicist that will be spoken of frequently in this chapter, who found that this reddening paradigm was more profound the further one looked out into the universe (a galaxy 100 million light years away will appear less “redshifted” than a galaxy 2 billion light years away, even if the two galaxies have the same compositions). This redshifting determined for Hubble that the universe was expanding, and he proved his findings through what is known as the Doppler Effect, which is the phenomenon that creates the redshifting Hubble used to determine that the universe was expanding. In this chapter, we will discuss the Doppler Effect, how it occurs, and what it represents. References Classical Doppler Effect - Wikipedia https://en.wikipedia.org/wiki/Doppler_effect Relativistic Doppler Effect - Wikipedia https://en.wikipedia.org/wiki/Relativistic_Doppler_effect Cosmological Redshift - COSMOS https://astronomy.swin.edu.au/cosmos/c/cosmological+redshift Cosmological Expansion - Wikipedia https://en.wikipedia.org/wiki/Expansion_of_the_universe Comoving and Proper Distance in Cosmology - David W. Hogg https://cds.cern.ch/record/387177/files/9905116.pdf Future of Cosmological Expansion - Wikipedia https://en.wikipedia.org/wiki/Future_of_an_expanding_universe Heat Death - Wikipedia https://en.wikipedia.org/wiki/Heat_death_of_the_universe Fate of the Universe - Wikipedia https://en.wikipedia.org/wiki/Ultimate_fate_of_the_universe Entropy - Wikipedia https://en.wikipedia.org/wiki/Entropy Thermodynamic Free Energy - Wikipedia https://en.wikipedia.org/wiki/Thermodynamic_free_energy

The 3rd Wetton lecture, 19th June 2018 delivered by Professor David W. Hogg, Center for Cosmology and Particle Physics, New York University In the last 20 years, the astronomical community has found thousands of planets around other stars, and we now know that many or even most stars in our Galaxy host planets. These planets have been found by making exceedingly precise measurements of stars. Some of the planets we find are extremely strange; most known planetary systems are very different from our own Solar System. Here we will look at how these measurements are made, and how planets are found in the data. The data analysis - the search for the planets in the mountains of data - involves cutting-edge ideas from data science and machine learning. These technologies are transforming our capabilities in astronomy.

Cite: Jo Bovy, Hans-Walter Rix, and David W. Hogg, “The Milky Way Has No Thick Disk,” The Astrophysical Journal 751 (June 1, 2012): id. 131.