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PRESENT BY DISTURBANCE. “A DM sub-halo passing by a stellar stream gives the stars in the stream a kick and perturbs their orbits, leading to a gap in the stream which is observable for sub-halo masses.” (DM = dark matter). https://lnkd.in/e6ifiQMn View in LinkedIn

PROBING WARM DARK MATTER. “The linear power spectrum, and hence the mass of WDM particles, can be probed via the Lyman-alpha forest. The Lyman-alpha forest is the absorption lines in spectra of galaxies and quasars from the Lyman-alpha electron transition in intergalactic neutral hydrogen ‘clouds’.” (WDM = Warm dark matter). https://lnkd.in/e6ifiQMn View in LinkedIn

THE AUTHOR. “NG, Y. JACK, KENAN PROFESSOR. Harvard University, Ph.D. Physics, 1974 (thesis advisor: J. Schwinger). Harvard University, M.A. Physics, 1969 (graduate advisor: S. Glashow). University of California at Berkeley, B.A. Physics, 1968. Postdoctoral Fellow, Institute for Advanced Study, Princeton, 1974-1976. Research Associate, Stanford Linear Accelerator Center, Stanford, 1976-1978.” https://lnkd.in/e98wCbH5 View in LinkedIn

THE PAPER. “Entropy and Gravitation—From Black Hole Computers to Dark Energy and Dark Matter, by Y. Jack Ng, Institute of Field Physics, Department of Physics and Astronomy, University of North Carolina, Chapel Hill.” https://lnkd.in/emmgb6JD View in LinkedIn

We are still peering haplessly into the heavens. https://lnkd.in/eDyMRAvC View in LinkedIn

“the light of sense " "Goes out, but with a flash that has revealed " "The invisible world.” " "WORDSWORTH, THE PRELUDE (1850) 5: 600-602. Free online version. https://lnkd.in/e6GepCV6) View in LinkedIn

RADICAL BIOLOGY. “Morowitz’s book “Energy Flow in Biology” laid out his pioneering thesis that “the energy that flows through a system acts to organize that system.” The Wikipedia entry for “Life” quotes Morowitz’s assertion that “life is a property of an ecological system rather than a single organism or species.” (A remarkable man). https://lnkd.in/efGrNub9 View in LinkedIn

PEERING INTO THE HEAVENS. “We can also probe the nature of dark matter (i.e. deviations from ‘vanilla’ cold dark matter which just interacts gravitationally) using astronomical and cosmological observations.” https://lnkd.in/e6ifiQMn View in LinkedIn

WAITING FOR GODOT. “To detect dark matter we need to know how it’s distributed, in particular in the Milky Way galaxy, and there has been significant recent (and ongoing) progress in this field from both observations and simulations.” https://lnkd.in/e6ifiQMn View in LinkedIn

ELEPHANT IN THE ROOM. “The ΛCDM cosmological model, in which the Universe is flat with 25% of the energy density being in the form of cold, non-baryonic, dark matter is a good fit to a wide range of observations (nucleosynthesis, CMB, large scale structure, type 1a supernovae). However we don’t (yet...) know what dark matter (or dark energy) is.” (ΛCDM = A-Cold-Dark-Matter standard model of cosmology; CMB = cosmic microwave background). https://lnkd.in/e6ifiQMn View in LinkedIn