How Quantum Mechanics Screws with our Perception of Reality Quantum physics says goodbye to reality Some physicists are uncomfortable with the idea that all individual quantum events are innately random. This is why many have proposed more complete theories, which suggest that events are at least partially governed by extra "hidden variables". Now physicists from Austria claim to have performed an experiment that rules out a broad class of hidden-variables theories that focus on realism -- giving the uneasy consequence that reality does not exist when we are not observing it (Nature 446 871). Some 40 years ago the physicist John Bell predicted that many hidden-variables theories would be ruled out if a certain experimental inequality were violated – known as "Bell's inequality". Bell's trick, therefore, was to decide how to orient the polarizers only after the photons have left the source. Many realizations of the thought experiment have indeed verified the violation of Bell's inequality.
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. Theoretical physicists are those scientists who work in that twilight zone cutting edge realm between reality and science fiction. 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. © 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). According to Einstein's general relativity, massive objects warp spacetime so that anything traveling through it, including light, takes a curving path. The effects would usually be tiny, so that we wouldn't notice the difference in most observations of stars, galaxies and other cosmic phenomena. Whereas it is too soon to know if these scenarios might describe the truth, they are intriguing. 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. The nature of dark matter is unknown, but physicists have suggested that it, like visible matter, is made up of particles. 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. 2. Several experiments are searching for dark matter, and some of them may have even already found it. 3. 4.
Dark energy and dark matter How world works. Bohr and beyond: a century of quantum physics › Opinion (ABC Science) In Depth › Analysis and Opinion Our understanding of the quantum world began with Niels Bohr's discovery of the quantum atom in 1913. Bohr would be astounded by where his theory has since led, says Professor David Jamieson. Bohr's discovery of the quantum nature of the atom, published when he was a young man of 28, was an important pioneering contribution to the earliest days of quantum physics. This field emerged to explain the common sense-defying behaviour of atoms, molecules and light at the smallest scales, forming the foundations on which we have built one of the greatest and most successful theories of all time — quantum mechanics. What is quite remarkable to modern eyes was that Bohr had very little to go on. The true nature of the atom as an incredibly tiny nucleus surrounded by a cloud of orbiting electrons had only been discovered a few years earlier, in the separate work of physicists Thomson and Rutherford. ^ to top Bohr's quantum atom: nature is digital From theory to evidence
Higgs boson: Call to rename particle to acknowledge other scientists 22 April 2013Last updated at 13:00 ET By Pallab Ghosh Science correspondent, BBC News "Fathers" of the Higgs, L-R: Francois Englert, Peter Higgs, Carl Hagen and Gerald Guralnik One of the scientists who helped develop the theory of the Higgs boson says the particle should be renamed. Carl Hagen believes the name should acknowledge the work of others - not just UK physicist Peter Higgs. The long-running debate has been rekindled following speculation that this year's Nobel Prize for Physics will be awarded for the Higgs theory. The detection of a particle thought to be the Higgs was announced at the Large Hadron Collider in July last year. American Prof Hagen told BBC News: "I have always thought that the name was not a proper one. Continue reading the main story “Start Quote Peter Higgs was treated as something of a rock star and the rest of us were barely recognised. End QuoteProf Carl HagenRochester University, New York Peter Higgs is open to a name change to "H Boson" Nobel Prize