Far out cosmology: dark energy and dark matter (Introduction)

by David Turell , Sunday, November 15, 2020, 15:17 (1467 days ago) @ David Turell

They MUST exist, but we do not know what they are:

http://cosmos.nautil.us/short/135/dark-matter-is-our-friend?mc_cid=f7a1ff6950&mc_ei...

"Dark matter is our friend. Dark matter creates the galaxies and all the other large structures that are held together by gravity. Without dark matter the universe would just be a thin soup of ordinary matter. There would be no galaxies, no stars, no heavy elements, no rocky planets, and no life. So we owe a tremendous debt to dark matter.

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"For various theoretical reasons, the most natural value of the total density of the universe is a quantity called critical density, and observations indicated that ordinary matter plus dark matter account for less than that. In 1991 my collaborators and I considered the possibility that the remainder was a form of energy that Einstein called the cosmological constant or, more generally, what we know today as dark energy. We worked out how a cosmological constant would affect the formation of gravitationally bound structures such as galaxies and galaxy clusters.

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"These models fit the COBE data, but the real confirmation did not come until 1998, when two competing teams of astronomers independently found that the expansion of the universe has been speeding up—the telltale effect of the cosmological constant. The clincher has been measurements by two follow-ups to COBE, NASA’s WMAP satellite and the European Space Agency’s Planck satellite, which confirm the predictions of the double-dark theory with fantastic precision.

"Even those of us who helped to create the model are amazed it works so well. Some astrophysicists have worried that its predictions might disagree with observations of certain regions, such as the smallest galaxies and the cores of galaxies or galaxy clusters. But improved simulations have refined the predictions and appear to have resolved these issues. We now at last have a picture of the evolution and structure of the universe that might actually be true.

"But the model does not tell us what dark matter and dark energy are; it simply captures their large-scale effects. We still have no direct evidence for either supersymmetry or WIMPs. Alternative explanations of dark matter have been proposed, but there is no convincing evidence for them, either.

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"Physicists and astronomers are working hard to identify dark matter and dark energy, and when we do, it could well represent a revolution in our understanding of the fundamental nature of the universe greater than the one that gave us the Standard Model.

"The ongoing cosmological revolution has implications so profound and far-reaching that it cannot help but alter how we humans view our place in the universe. We will need to seek new modes of understanding. Although no one ever imagined the bizarre universe that science is discovering, we can draw on the entire human experience to try to make sense of it.

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"Our goal has been to explain how we humans arose from and fit into the modern universe. We seek to connect ideas such as the double-dark universe with other aspects of science and philosophy, including ancient wisdom traditions. For example, Native American and other traditional cultures hold that humans arose from the earth and bear close relationships with other animals. That is consonant with modern science.

"The brief moment of cosmic inflation that started our expanding universe has analogues in ancient Egyptian creation myths and in the ideas of Kabbalah, medieval Jewish mysticism.

"The first three parts of the Kabbalistic tree of life are Keter, Hokhmah, and Binah. Like Keter, eternal inflation is the infinite source of all possibilities; like Hokhmah, cosmic inflation is the exit from eternity that prepares the blueprint for the future universe; like Binah, the expanding universe has turned the primal plan into spacetime and galaxies. Binah was seen as female in Kabbalah. It is a bit startling to identify the expanding universe with a womb, yet there is something reassuring about positing motherly understanding as a cosmic quality. Hokhmah was seen as male, while Keter was beyond gender, nicely balancing things out.

"The idea that any aspect of the universe is either male or female is, of course, not to be taken literally. But there is no reason that people outside science should process the ideas of modern cosmology in the same way that scientists have. Science is discovering a remarkable unity and intricacy to the natural world, and mythological concepts can perhaps help us experience these connections."

Comment: Conundrums wrapped in mysteries. We know of dark matter and dark energy by their effects. God creates in mysterious ways and Jewish mystics in the Kabbalah had a clue!