


 💫Si eres Autor prueba la opción Nueva Entrada




'Dark Sky' is the Open Source Dark Matter Simulator

May 7, 2015 // 05:00 AM EST

Pretty cool, huh?

What you are looking at is a visualization from the Dark Sky simulations, one of the largest and most sophisticated models of how dark matter evolves that has ever been produced.

Each point traces the density of dark matter, color-coded according to its instantaneous velocity—the speed and direction of the particle at a certain point in time—and interacting with other particles according to a complex algorithm which simulates the effects of gravity.

Simulations like Dark Sky, made by a small conglomerate of scientists from Los Alamos National Laboratory, Stanford, Paris Institute of Astrophysics, University of Illinois, and the University of Chicago, help fill in the gaps not only between particle physics and cosmology, but also the first moments of our universe to the present day. They provide crucial insight into the mystery of dark matter, which is generally considered to be the cosmological scaffolding upon which everything else in the universe is built.
In the standard cosmological model, dark energy comprises roughly 68 percent of our universe, dark matter about 27 percent, and baryonic matter—which we might consider as "normal" or visible matter—accounts for a measly 5 percent of the makeup of the universe. Clearly, dark matter and dark energy are integral to the existence of life as we know it, but despite their importance, we know remarkably little about them.

This visualization by Ralf Kaehler shows a slice of one of the dark sky simulations, where the particles are built up in Morton-order, just like they are stored in memory and on a disk.

This is where Dark Sky comes in, hoping to shed some light on the situation, so to speak, by rendering the interactions between dark matter and dark energy visible.

"[Dark Sky] is a statistically similar universe to our own, but it’s not actually simulating our universe," said Sam Skillman, a postdoctoral researcher at Stanford’s Kavli Institute for Particle Astrophysics and Cosmology. “We run simulations, each of which is representative of what a universe like ours should look like. Then we compare it to our universe and see if it’s consistent.”

Dark matter was first postulated by Jan Oort in 1932 based on his observation of the stellar motion within the Milky Way. The measurements which led him to the conclusion that dark matter must exist were later discovered to be entirely erroneous, however, so the real theoretical origins of dark matter reside with Fritz Zwicky. In 1933, Zwicky discovered that the motion of a galaxy cluster he was observing was not conducive to the amount of mass calculated to be present in that cluster.

This "missing mass" observed by Zwicky is now referred to as dark matter, the invisible scaffolding of the universe which makes the formation of baryonic structures like galaxies possible. Understanding dark matter will provide crucial insight into early galactic formation, an area of our universal history about which we know relatively little.

Read more Perfect Worlds

2 comentarios:

  1. I had a feeling that the matter that we can see, the baryonic matter, was less than 50% of the universe, but not as little as 5%! I am surprised! Thank you for the information, Cindy. I can only conclude that baryonic matter is a whole lot more dense than dark matter or dark energy, otherwise there would be no equilibrium, and the chaos would be much worse. What do you think?

  2. I quite agree Paula. Fore every reaction there is an equal and opposite reaction. I believe that law holds true for dark energy and dark matter . Energy and mass.