///////////////////Relativity passes new test of time
14 November 2007, 11:33:37
Scientists will have to look harder for physics beyond the Standard Model
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The industry of life
01 November 2007, 12:00:00
Molecular machines and the new thermodynamics
//////////////////30 YR DPM FORT
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How Cell Phones Can Cause Autism
13 November 2007, 13:03:00 Dr. Mercola
The incidence of Autism has increased almost 60-fold since the 1970’s. There is no consensus as to what the exact cause of the increase is, but new evidence points towards an as yet little regarded possibility -- the electromagnetic radiation (EMR) emitted by cell phones and other wireless devices, in combination with heavy metal poisoning.
A new study published in the Journal of the Australasian College of Nutritional and Environmental Medicine examined the results of removing all EMR from the presence of autistic children who were undergoing heavy metal detoxification treatment. The results were dramatic, and the children showed far greater improvement than those who underwent heavy metal detoxification in the presence of EMR.
Many have postulated that autism may result from poisoning with metals such as mercury. But heavy metal detoxification protocols have previously had only mixed results as a method of treatment. EMR expert Dr. George Carlo, however, noted that in the presence of EM radiation, cells tend to go into emergency mode and “close”, which could trap heavy metals and other toxins within the cell
Wireless Radiation in the Etiology and Treatment of Autism: Clinical Observations and Mechanisms
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The Rise and Fall of Pharmacracy
13 November 2007, 13:01:50 Dr. Mercola
By Christopher Kent, DC, JD
Psychiatrist Thomas S. Szasz (1) has written extensively on the medicalization of American politics. Medicalization is defined as a process or tendency whereby the phenomena, which had belonged to another field such as education, law, religion, and so on, have been redefined as medical phenomena. (2) Thus, medicalization is a process by which the medical profession asserts authority over a sphere of life previously overseen by guardians of morality.
Szasz describes the ideologies of legitimization: theocracy (God’s will); democracy (consent of the governed); socialism (economic equality); and pharmacracy (the therapeutic state). The emergence of the therapeutic state is a product of the 20th century.
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New Research on How Sunshine Decreases Infections
12 November 2007, 13:44:06 Dr. Mercola
A study of more than 2,000 women has found those with higher vitamin D levels showed fewer aging-related changes in their DNA. A second study, examining almost 1,000 patients in West Africa, showed that low vitamin D levels are common among tuberculosis (TB) patients. Lack of vitamin D has been linked in previous studies to multiple sclerosis, rheumatoid arthritis, and other diseases.
Cells have built-in DNA clocks, known as telomeres. Measuring the length of these strands of DNA is one way of examining the aging process at a cellular level.
Women with higher levels of vitamin D are more likely to have longer telomeres, and vice versa. This means that people with higher levels of vitamin D may actually age more slowly than people with lower levels of vitamin D. No wonder vitamin D has a protective effect on so many diseases, ranging from MS and TB to heart disease and cancer -- it keeps your body young!
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Put Down the Bacon! Obesity Causes Cancer
02 November 2007, 12:20:29 Dr. Mercola
There is more evidence than ever that a person who weighs too much is more likely to develop several types of cancer, according to a landmark report out Wednesday.
And forget eating bacon, sausage and lunchmeat. No amount is considered completely safe, according to the analysis from the American Institute for Cancer Research and the World Cancer Research Fund.
A panel of experts from around the world reviewed more than 7,000 large-scale studies and spent five years developing the report, which includes 10 recommendations for cancer prevention.
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Can Smoking Cause Depression?
30 October 2007, 13:07:19 Dr. Mercola
Smoking cigarettes may make teens more susceptible to depression, alcohol abuse, and illegal drug use, a new report states.Based on data from a government drug use survey, researchers concluded that teens who smoke are nine times more likely to abuse alcohol and 13 times more likely to abuse illegal drugs than teens who don't smoke.
Sources:
WebMD Medical News October 23, 2007
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Foundations of Big Bang Cosmology
The Big Bang model of cosmology rests on two key ideas that date back to the early 20th century: General Relativity and the Cosmological Principle. By assuming that the matter in the universe is distributed uniformly on the largest scales, one can use General Relativity to compute the corresponding gravitational effects of that matter. Since gravity is a property of space-time in General Relativity, this is equivalent to computing the dynamics of space-time itself. The story unfolds as follows:
Given the assumption that the matter in the universe is homogeneous and isotropic (The Cosmological Principle) it can be shown that the corresponding distortion of space-time (due to the gravitational effects of this matter) can only have one of three forms, as shown schematically in the picture at left. It can be "positively" curved like the surface of a ball and finite in extent; it can be "negatively" curved like a saddle and infinite in extent; or it can be "flat" and infinite in extent - our "ordinary" conception of space. A key limitation of the picture shown here is that we can only portray the curvature of a 2-dimensional plane of an actual 3-dimensional space! Note that in a closed universe you could start a journey off in one direction and, if allowed enough time, ultimately return to your starting point; in an infinite universe, you would never return.
Before we discuss which of these three pictures describe our universe (if any) we must make a few disclaimers:
Because the universe has a finite age (~13.7 billion years) we can only see a finite distance out into space: ~13.7 billion light years. This is our so-called horizon. The Big Bang Model does not attempt to describe that region of space significantly beyond our horizon - space-time could well be quite different out there.
It is possible that the universe has a more complicated global topology than that which is portrayed here, while still having the same local curvature. For example it could have the shape of a torus (doughnut). There may be some ways to test this idea, but most of the following discussion is unaffected.
Matter plays a central role in cosmology. It turns out that the average density of matter uniquely determines the geometry of the universe (up to the limitations noted above). If the density of matter is less than the so-called critical density, the universe is open and infinite. If the density is greater than the critical density the universe is closed and finite. If the density just equals the critical density, the universe is flat, but still presumably infinite. The value of the critical density is very small: it corresponds to roughly 6 hydrogen atoms per cubic meter, an astonishingly good vacuum by terrestrial standards! One of the key scientific questions in cosmology today is: what is the average density of matter in our universe? While the answer is not yet known for certain, it appears to be tantalizingly close to the critical density.
Given a law of gravity and an assumption about how the matter is distributed, the next step is to work out the dynamics of the universe - how space and the matter in it evolves with time. The details depend on some further information about the matter in the universe, namely its density (mass per unit volume) and its pressure (force it exerts per unit area), but the generic picture that emerges is that the universe started from a very small volume, an event later dubbed the Big Bang, with an initial expansion rate. For the most part this rate of expansion has been slowing down (decelerating) ever since due to the gravitational pull of the matter on itself. A key question for the fate of the universe is whether or not the pull of gravity is strong enough to ultimately reverse the expansion and cause the universe to collapse back on itself. In fact, recent observations have raised the possibility that the expansion of the universe might in fact be speeding up (accelerating), raising the possibility that the evolution of the universe is now dominated by a bizarre form of matter which has a negative pressure.
The picture above shows a number of possible scenarios for the relative size of the universe vs. time: the bottom (green) curve represents a flat, critical density universe in which the expansion rate is continually slowing down (the curves becomes ever more horizontal). The middle (blue) curve shows an open, low density universe whose expansion is also slowing down, but not as much as the critical density universe because the pull of gravity is not as strong. The top (red) curve shows a universe in which a large fraction of the matter is in a form dubbed "dark energy" which is causing the expansion of the universe to speed up (accelerate). There is growing evidence that our universe is following the red curve.
Please avoid the following common misconceptions about the Big Bang and expansion:
The Big Bang did not occur at a single point in space as an "explosion." It is better thought of as the simultaneous appearance of space everywhere in the universe. That region of space that is within our present horizon was indeed no bigger than a point in the past. Nevertheless, if all of space both inside and outside our horizon is infinite now, it was born infinite. If it is closed and finite, then it was born with zero volume and grew from that. In neither case is there a "center of expansion" - a point from which the universe is expanding away from. In the ball analogy, the radius of the ball grows as the universe expands, but all points on the surface of the ball (the universe) recede from each other in an identical fashion. The interior of the ball should not be regarded as part of the universe in this analogy.
By definition, the universe encompasses all of space and time as we know it, so it is beyond the realm of the Big Bang model to postulate what the universe is expanding into. In either the open or closed universe, the only "edge" to space-time occurs at the Big Bang (and perhaps its counterpart the Big Crunch), so it is not logically necessary (or sensible) to consider this question.
It is beyond the realm of the Big Bang Model to say what gave rise to the Big Bang. There are a number of speculative theories about this topic, but none of them make realistically testable predictions as of yet.
To this point, the only assumption we have made about the universe is that its matter is distributed homogeneously and isotropically on large scales. There are a number of free parameters in this family of Big Bang models that must be fixed by observations of our universe. The most important ones are: the geometry of the universe (open, flat or closed); the present expansion rate (the Hubble constant); the overall course of expansion, past and future, which is determined by the fractional density of the different types of matter in the universe. Note that the present age of the universe follows from the expansion history and present expansion rate.
As noted above, the geometry and evolution of the universe are determined by the fractional contribution of various types of matter. Since both energy density and pressure contribute to the strength of gravity in General Relativity, cosmologists classify types of matter by its "equation of state" the relationship between its pressure and energy density. The basic classification scheme is:
Radiation: composed of massless or nearly massless particles that move at the speed of light. Known examples include photons (light) and neutrinos. This form of matter is characterized by having a large positive pressure.
Baryonic matter: this is "ordinary matter" composed primarily of protons, neutrons and electrons. This form of matter has essentially no pressure of cosmological importance.
Dark matter: this generally refers to "exotic" non-baryonic matter that interacts only weakly with ordinary matter. While no such matter has ever been directly observed in the laboratory, its existence has long been suspected for reasons discussed in a subsequent page. This form of matter also has no cosmologically significant pressure.
Dark energy: this is a truly bizarre form of matter, or perhaps a property of the vacuum itself, that is characterized by a large, negative pressure. This is the only form of matter that can cause the expansion of the universe to accelerate, or speed up.
One of the central challenges in cosmology today is to determine the relative and total densities (energy per unit volume) in each of these forms of matter, since this is essential to understanding the evolution and ultimate fate of our universe.
////////////////////DEEP SPACETIME=http://www.pbs.org/deepspace/timeline/
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