Cosmologic philosophy: more fine tuning (Introduction)

by David Turell , Monday, September 21, 2015, 04:43 (3351 days ago) @ David Turell

No one knows why the constants have the value they have. They just ARE:-http://aeon.co/magazine/science/the-universal-constants-that-drive-physicists-mad/-"So, let's assume that these constants really are constant. Are they fundamental? Are some more fundamental than others? What do we even mean by ‘fundamental' in this context? One way to approach the issue would be to ask what is the smallest set of constants from which the others can be derived. Sets of two to 10 constants have been proposed, but one useful choice has been just three: h, c and G, collectively representing relativity and quantum theory.-***
"In 1899, Max Planck, who founded quantum physics, examined the relations among h, c and G and the three basic aspects or dimensions of physical reality: space, time, and mass. Every measured physical quantity is defined by its numerical value and its dimensions. We don't quote c simply as 300,000, but as 300,000 kilometres per second, or 186,000 miles per second, or 0.984 feet per nanosecond. The numbers and units are vastly different, but the dimensions are the same: length divided by time. In the same way, G and h have, respectively, dimensions of [length3/(mass x time2)] and [mass x length2/time]. From these relations, Planck derived ‘natural' units, combinations of h, c and G that yield a Planck length, mass and time of 1.6 x 10-35 metres, 2.2 x 10-8 kilogrammes, and 5.4 x 10-44 seconds. Among their admirable properties, these Planck units give insights into quantum gravity and the early Universe.-"But some constants involve no dimensions at all. These are so-called dimensionless constants - pure numbers, such as the ratio of the proton mass to the electron mass. That is simply the number 1836.2 (which is thought to be a little peculiar because we do not know why it is so large). According to the physicist Michael Duff of Imperial College London, only the dimensionless constants are really ‘fundamental', because they are independent of any system of measurement. Dimensional constants, on the other hand, ‘are merely human constructs whose number and values differ from one choice of units to the next'.-"Perhaps the most intriguing of the dimensionless constants is the fine-structure constant ?. It was first determined in 1916, when quantum theory was combined with relativity to account for details or ‘fine structure' in the atomic spectrum of hydrogen. In the theory, ? is the speed of the electron orbiting the hydrogen nucleus divided by c. It has the value 0.0072973525698, or almost exactly 1/137.-"Today, within quantum electrodynamics (the theory of how light and matter interact), ? defines the strength of the electromagnetic force on an electron. This gives it a huge role. Along with gravity and the strong and weak nuclear forces, electromagnetism defines how the Universe works. But no one has yet explained the value 1/137, a number with no obvious antecedents or meaningful links. The Nobel Prize-winning physicist Richard Feynman wrote that ? has been ‘a mystery ever since it was discovered… a magic number that comes to us with no understanding by man. You might say the “hand of God” wrote that number, and “we don't know how He pushed his pencil”.'-"Whether it was the ‘hand of God' or some truly fundamental physical process that formed the constants, it is their apparent arbitrariness that drives physicists mad. Why these numbers? Couldn't they have been different?
" (my bold)-Comments: If these constants were any different there would be no humans