Science, Culture and Integral Yoga

...Active Galactic Nuclei - thought to be powered by supermassive black holes that devour large amounts of matter - are the most likely candidate for the source of the highest-energy cosmic rays that hit Earth.

Using the Pierre Auger Observatory, the team of scientists found that the sources of the highest-energy particles are not distributed uniformly across the sky. Instead, the Auger results link the origins of these mysterious particles to the locations of nearby galaxies that have active nuclei in their centres.

Active Galactic Nuclei (AGN) have long been considered sites where high-energy particle production might take place. They swallow gas, dust and other matter from their host galaxies and spew out particles and energy.

While most galaxies have black holes at their centre, only a fraction of all galaxies have an AGN. The exact mechanism of how AGNs can accelerate particles to energies 100 million times higher than the most powerful particle accelerator on Earth is still a mystery. ... more »

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Monday, January 28

Universe may be 4 billion years older -- possible solution to dark energy enigma

by ronjon on January 28, 2008 02:13PM (PST)

“Dark energy is the largest contribution — 76 per cent — to the content of the universe in our present standard cosmology. It is postulated as a smooth energy in the vacuum of space, which makes the expansion of the universe want to accelerate,” Dr. Wiltshire said. “But why such stuff should exist, with a particular tiny density, is a complete mystery."

Galaxies do appear to be moving away from each other and at an ever-increasing rate. But Dr Wiltshire claims such “acceleration” is an illusion, due to us misinterpreting observations based in galaxies, where space is not expanding. Clusters of galaxies are spread in filaments and bubbles around huge voids. Most of the volume of the universe, where space is expanding, is in empty voids. Once variations within this uneven distribution are taken into account, he says, we don't need exotic dark energy.

Dr Wiltshire’s latest research, published in New Journal of Physics, Physical Review Letters, and Astrophysical Journal Letters, focuses on solving for an average of the lumpy distribution of matter in the universe as it evolved, rather than a smooth distribution assumed 80-90 years ago by Einstein, Friedman and Lemaître, whose models are still the standard cosmological models today. ... more »

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Friday, January 11

Mathematics, Purpose, and Truth: An Interview with Astrophysicist Janna Levin

by ronjon on January 11, 2008 03:48PM (PST)

Thanks to RY Deshpande for recommending this article. ~ rj

As a theoretical physicist, Janna Levin probes whether the universe is finite or infinite. As a novelist, she explored the separate but parallel lives of two influential 20th-century scientists: Kurt Gödel and Alan Turing. Their work laid the foundations for computer intelligence while challenging fundamental notions about how we can know what is true. ... more »

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Chandra data reveal black holes spinning near speed of light may effect new star formation

by ronjon on January 11, 2008 12:07PM (PST)

...According to Einstein's theory, a rapidly spinning black hole makes space itself rotate. This effect, coupled with gas spiraling toward the black hole, can produce a rotating, tightly wound vertical tower of magnetic field that flings a large fraction of the inflowing gas away from the vicinity of the black hole in an energetic, high-speed jet...

One significant consequence of powerful, black hole jets in galaxies in the centers of galaxy clusters is that they can pump enormous amounts of energy into their environments, and heat the gas around them. This heating prevents the gas from cooling, and affects the rate at which new stars form, thereby limiting the size of the central galaxy. Understanding the details of this fundamental feedback loop between supermassive black holes and the formation of the most massive galaxies remains an important goal in astrophysics. ... more »

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Tuesday, January 8

4 Year-Old Postmodern Cosmology Challenges 20-Year Mainstream Cosmology

by ronjon on January 8, 2008 10:19AM (PST)

Postmodern cosmology is celebrating its fourth anniversary with the publishing of its Big Bang cosmology theory in a book entitled "How Dark Matter Created Dark Energy and the Sun". The original form of the cosmology theory is described in Part X under the title, "Cosmic-Ray Cosmology: Drexler's Unified Theory of Dark Matter, Accelerating Expansion, and Star Formation."

The postmodern Big Bang cosmology theory is based upon utilizing the tangible Relativistic-Proton dark matter, which is related to cosmic-ray protons. Postmodern cosmology is able to use many observations that are more astronomical and relies on considerably fewer hypotheses than does today's mainstream Big Bang cosmology, which is based upon intangible Cold Dark Matter.

...the problem with current Big Bang cosmology is not a shortage of available relevant astronomical observations, but that the Cold Dark Matter hypotheses cannot generally show compatibility with an added independent astronomical observation without adding another new hypothesis. On the other hand, increasing the number of astronomical observations will increase the net significance for the postmodern Big Bang cosmology, which utilizes Relativistic-Proton dark matter. ... more »

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