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The Elegant Universe Part 2 - String's The Thing - PBS NOVA

The Elegant Universe Part 2 - String's The Thing - PBS NOVA

The Search For The History Of The Universe's Light Emission The light emitted from all objects in the Universe during its entire history - stars, galaxies, quasars etc. forms a diffuse sea of photons that permeates intergalactic space, referred to as "diffuse extragalactic background light" (EBL). Scientists have long tried to measure this fossil record of the luminous activity in the Universe in their quest to decipher the history and evolution of the Cosmos, but its direct determination from the diffuse glow of the night sky is very difficult and uncertain. Very high energy (VHE) gamma-rays, some 100,000,000,000 times more energetic than normal light, offer an alternative way to probe this background light, and UK researchers from Durham University in collaboration with international partners used the High Energy Stereoscopic System (HESS) gamma-ray telescopes in the Khomas Highlands of Namibia to observe several quasars (the most luminous VHE gamma-ray sources known) with this goal in mind. Source: PPARC

Dark Matter: The Larger Invisible Universe | Joe Arrigo PERSPECTIVE Normal matter—you, me, oatmeal, mountains, oceans, moons, planets, galaxies—make up about twenty-percent of the universe; the other eighty-percent is dark matter—star-stuff we cannot see or detect…yet. Why are scientists so certain this enigmatic matter exists? Because the evidence permeates the universe, first observed by Fritz Zwicky, when he measured the motions of galaxies and calculated that there wasn’t enough visible matter to affect galaxies to extent they were being pulled around.WWWFirst, there isn’t enough gravitational force within galaxies to bind and hold them in their current formation; then there is an invisible element that keeps them rotating faster than scientists would expect, clusters of galaxies bend and distort light more than they should, and supercomputer simulations exhibit that clouds of ordinary matter in the early universe did not have enough gravity to create the tight formations of galaxies we now see.

The Theory of Everything | Joe Arrigo PERSPECTIVE The above equation was written by Dr. Michio Kaku, theoretical physicist, who gradu­ated first in his physics class at Harvard, and, when he was in high school built a 2.3 million electron volt atom-smasher in his parents garage. It is an equation for String Field Theory—a theory that may unite The Theory of Relativity with Quantum Theory, into a uni­fied theory called The Theory of Everything. For thirty years Einstein sought a unified theory of physics that would integrate all the forces of nature into a single beautiful tapestry. String Theory says that at the subatomic level, there are vibrating strings—that particles like protons, electrons and quarks are nothing but musical notes on a tiny vibrating string, that all the stupendous activities in the universe are born from a sub-atomic loop of energy deep within all matter. At this moment, no one on earth is smart enough to solve this theory. © Joe Arrigo

In a "Rainbow" Universe Time May Have No Beginning What if the universe had no beginning, and time stretched back infinitely without a big bang to start things off? That's one possible consequence of an idea called "rainbow gravity," so-named because it posits that gravity's effects on spacetime are felt differently by different wavelengths of light, aka different colors in the rainbow. Rainbow gravity was first proposed 10 years ago as a possible step toward repairing the rifts between the theories of general relativity (covering the very big) and quantum mechanics (concerning the realm of the very small). The idea is not a complete theory for describing quantum effects on gravity, and is not widely accepted. Nevertheless, physicists have now applied the concept to the question of how the universe began, and found that if rainbow gravity is correct, spacetime may have a drastically different origin story than the widely accepted picture of the big bang. Yet the concept has its critics.

Four things you might not know about dark matter Not long after physicists on experiments at the Large Hadron Collider at CERN laboratory discovered the Higgs boson, CERN Director-General Rolf Heuer was asked, “What’s next?” One of the top priorities he named: figuring out dark matter. Dark matter is five times more prevalent than ordinary matter. It seems to exist in clumps around the universe, forming a kind of scaffolding on which visible matter coalesces into galaxies. Dark matter shows up periodically in the media, often when an experiment has spotted a potential sign of it. Here are four facts to get you up to speed on one of the most exciting topics in particle physics: 1. Illustration by: Sandbox Studio, Chicago At this moment, several experiments are on the hunt for dark matter. In the 1930s, astrophysicist Fritz Zwicky was observing the rotations of the galaxies that form the Coma cluster, a group of more than 1000 galaxies located more than 300 million light years from Earth. 2. 3. 4. First, they could detect it directly.

Dark energy and dark matter How Quantum Mechanics Screws with our Perception of Reality How world works. Quantum Mechanics and Reality, by Thomas J McFarlane © Thomas J. McFarlane 1995www.integralscience.org Most traditional [spiritual] paths were developed in prescientific cultures. Consequently, many of their teachings are expressed in terms of cosmologies or world views which we no longer find relevant. . .The question then naturally arises: Is it possible to incorporate both science and mysticism into a single, coherent world view? The primary purpose of this essay is to explain how quantum mechanics shows that the materialistic common sense notion of reality is an illusion, i.e., that the objective existence of the world is an illusion. The appearance of an objective world distinguishable from a subjective self is but the imaginary form in which Consciousness Perfectly Realizes Itself. Now listen to Niels Bohr, the pioneer of 20th century physics: An independent reality, in the ordinary physical sense, can neither be ascribed to the phenomena nor to the agencies of observation. [3] To quote Bohr and Heisenberg once more,

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