13 DEC 2011 by ideonexus

 The Creation of Carbon in Stars

The first step occurs when older stars start to accumulate helium, which is produced when two hydrogen nuclei collide and fuse with each other. This fusion is how stars create the energy that warms us. Two helium atoms can in turn collide to form beryllium, an atom whose nucleus contains four protons. Once beryllium is formed, it could in principle fuse with a third helium nucleus to form carbon. But that doesn't happen, because the isotope of beryllium that is formed decays almost immediatel...
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Requires a very delicate balance of natural laws. If the strong nuclear force were to change by as little as 0.5 percent, there would be no carbon or oxygen in the Universe.

13 DEC 2011 by ideonexus

 Carbon VS Silicon Life

Though one might imagine "living" organisms such as intelligent computers produced from other elements, such as silicon, it is doubtful that life could have spontaneously evolved in the absence of carbon. The reasons for that are technical but have to do with the unique manner in which carbon bonds with other elements. Carbon dioxide, for example, is gaseous at room temperature, and biologically very useful. Since silicon is the element directly below carbon on the periodic table, it has simi...
Folksonomies: life alien life xenobiology
Folksonomies: life alien life xenobiology
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While we can imagine living computers, it is hard to imagine silicon life spontaneously forming in the universe.

13 DEC 2011 by ideonexus

 The Strong Anthropic Principle

The weak anthropic principle is not very controversial. But there is a stronger form that we will argue for here, although it is regarded with disdain among some physicists. The strong anthropic principle suggests that the fact that we exist imposes constraints not just on our environment but on the possible form and content of the laws of nature themselves. The idea arose because it is not only the peculiar characteristics of our solar system that seem oddly conducive to the development of h...
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Our existence puts constraints on the very laws of nature.

08 JUN 2011 by ideonexus

 Everything Comes from Stars

What gravity is and why it is, no one knows. Albert Einstein spent most of his life trying to figure it out, but the secret eluded him. it is simply a fact that everything in the universe with mass pulls on everything else. If it weren't for the initial outward impetus of the Big Bang, gravity would have caused the entire universe to collapse into a heap. (Indeed, someday the cosmic collapse may happen, if and when the initial impetus is expended, although the best evidence suggests that the ...
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The Big Bang to the formation of stars, which formed the elements crucial to life. It takes 1,000 calories of sunlight to evaporate one thimbleful of water.