After Nixon's election, problems still continued. For many months the North and South famously debated over the shape of the table that would be used at the Paris Peace Conference. The North favored a circular table, in which all parties, including Viet Cong representatives, would appear to be equal in importance. The South argued that only a rectangular table was acceptable, for only a rectangle could show two distinct sides to the conflict, the North and South. Eventually a compromise was reached, in which representatives of the North and South government would sit at a circular table, with members representing all other parties sitting on individual square tables around them.
For starters, how about we talk a little bit about evidence? Let's take a subject that is central, core Science, but has no immediate hot-button relevance to Religion.
PeacfulNCurious, how much do you know about the atom? Neither of us have ever seen one. Then again, neither of us have ever seen anything else!
Note: In this sense, I take the liberty of including photons as, in a functional way, part of the atom structure, specifically part of the Quantum ElectroDynamic, or QED, structural understanding of the atom. Science nerds love to call it QED because that has for centuries been the last line of every geometry proof: "quod erat demonstrandum", ie., "(that) which was necessary to be proved". As all nerds know, the Pun is the Highest form of Humor.
From one point of view (ah! puns!) all we have ever seen is photons. Ask David Hume about that. But I digress.
Neither of us have ever seen an atom, so's we'd know it, at least not with the naked eye.
PeacfulNCurious, you've asked the forum a lot of questions. Can we ask you some? Is that fair?
PeacfulNCurious, do you believe in (acknowledge the existence, the universality, the accepted wisdom about) atoms? Things you've never seen?
Scientists are geeks, in that they love gadgets, by which they are confident they have the ability to EXTEND THE POWER OF THEIR FIVE SENSES.
Galileo used the lenses of Dutch lensgrinders to create the telescope, enabling him to see what could not be seen.
PeacfulNCurious, do you trust what you see thru telescopes and binoculars?
Nearly 2000 years earlier, Eratosthenes measured the diameter of the earth to a very respectable degree of accuracy:
QUOTE (-> | QUOTE | After Nixon's election, problems still continued. For many months the North and South famously debated over the shape of the table that would be used at the Paris Peace Conference. The North favored a circular table, in which all parties, including Viet Cong representatives, would appear to be equal in importance. The South argued that only a rectangular table was acceptable, for only a rectangle could show two distinct sides to the conflict, the North and South. Eventually a compromise was reached, in which representatives of the North and South government would sit at a circular table, with members representing all other parties sitting on individual square tables around them.
For starters, how about we talk a little bit about evidence? Let's take a subject that is central, core Science, but has no immediate hot-button relevance to Religion.
PeacfulNCurious, how much do you know about the atom? Neither of us have ever seen one. Then again, neither of us have ever seen anything else!
Note: In this sense, I take the liberty of including photons as, in a functional way, part of the atom structure, specifically part of the Quantum ElectroDynamic, or QED, structural understanding of the atom. Science nerds love to call it QED because that has for centuries been the last line of every geometry proof: "quod erat demonstrandum", ie., "(that) which was necessary to be proved". As all nerds know, the Pun is the Highest form of Humor.
From one point of view (ah! puns!) all we have ever seen is photons. Ask David Hume about that. But I digress.
Neither of us have ever seen an atom, so's we'd know it, at least not with the naked eye.
PeacfulNCurious, you've asked the forum a lot of questions. Can we ask you some? Is that fair?
PeacfulNCurious, do you believe in (acknowledge the existence, the universality, the accepted wisdom about) atoms? Things you've never seen?
Scientists are geeks, in that they love gadgets, by which they are confident they have the ability to EXTEND THE POWER OF THEIR FIVE SENSES.
Galileo used the lenses of Dutch lensgrinders to create the telescope, enabling him to see what could not be seen.
PeacfulNCurious, do you trust what you see thru telescopes and binoculars?
Nearly 2000 years earlier, Eratosthenes measured the diameter of the earth to a very respectable degree of accuracy:
Eratosthenes made a surprisingly accurate measurement of the circumference of the Earth. Details were given in his treatise On the measurement of the Earth which is now lost. However, some details of these calculations appear in works by other authors such as Cleomedes, Theon of Smyrna and Strabo. Eratosthenes compared the noon shadow at midsummer between Syene (now Aswan on the Nile in Egypt) and Alexandria. He assumed that the sun was so far away that its rays were essentially parallel, and then with a knowledge of the distance between Syene and Alexandria, he gave the length of the circumference of the Earth as 250,000 stadia.
Of course how accurate this value is depends on the length of the stadium and scholars have argued over this for a long time. The article [11] discusses the various values scholars have given for the stadium. It is certainly true that Eratosthenes obtained a good result, even a remarkable result if one takes 157.2 metres for the stadium as some have deduced from values given by Pliny. It is less good if 166.7 metres was the value used by Eratosthenes as Gulbekian suggests in [11].
<br>PeacfulNCurious, do you trust the common belief that the earth is roughly 25,000 miles in circumference?
So nerdy Scientists have long realized that machinery, physical and mental, ee. gg., levers and formulas, have the power to extend our physical and mental powers, and I mean to discuss in particular observational machinery. I'll tell you where I'm heading: the spectroscope!
Great minds as diverse as Newton the Physicist and Goethe the poet became fascinated by prisms, and their ability to break a beam of light into a colored spectrum (Newton's word -- Latin: "ghost").
PeacfulNCurious, do you . . . naah, I won't go there.
This brief (Fair Use) clip from the Britannica (which I paid for, on CD) tells about the glorious, thrilling early history of the spectroscope:
| QUOTE | The composite nature of white light was first demonstrated by Isaac Newton (1664) when he allowed sunlight entering a round hole in a shutter to pass through a glass prism and fall on a screen. The resulting elongated image of the Sun, showing the same gradation of colours as the rainbow, he called a spectrum. In 1800 William Herschel studied the solar spectrum with the aid of thermometers and found the greatest effect beyond the red end, thus discovering infrared radiation. In 1801 Johann Wilhelm Ritter, studying the effect of solar radiation upon silver salts, found this action extending beyond the violet, thus discovering ultraviolet rays.
The first connection between spectral colour and wavelength appeared in 1802, when Thomas Young applied his wave theory of light to calculate the approximate wavelengths of the seven colours recognized by Newton. In 1814 Joseph von Fraunhofer modified Newton's experiment by substituting a narrow slit for a hole and a telescope for a screen. Under these conditions he observed the continuous spectrum of the Sun interrupted by hundreds of dark lines, still known as Fraunhofer lines. Fraunhofer constructed the first diffraction gratings, and with these he determined the wavelengths corresponding to many of these lines. Although Fraunhofer and others observed that certain bright lines in the spectra of flames seemed to coincide with dark lines in the solar spectrum, it remained for Gustav Robert Kirchhoff in 1859 to enunciate the generality of this phenomenon and to emphasize the fact that each species of atom has a uniquely characteristic spectrum.
<br>Fraunhofer was perhaps a good industrious capitalist, trying to make it in the lensgrinding business. He was probably more motivated by the irritating unwanted spectra around the edges of telescope images due to chromatic aberration, caused by the fact that blue light bends more than red light (due to its higher energy) when passing from air to glass to air.
The method used is achromatic lenses, the invention of which were Fraunhofer's chief concern at that time. Since Flint Glass and Crown Glass have different refractive indices, due to different chemistry, by making a sandwich of two half lenses of different glass, one can get some control over chromatic aberration that spoils a good view of a star.
But the thing that impresses me most about this guy was his craftsmanship. Here's a brief discussion of early grating manufacture, from http://snl.mit.edu/papers/Nanoruler-White-Paper3.pdf
QUOTE (-> | QUOTE | The composite nature of white light was first demonstrated by Isaac Newton (1664) when he allowed sunlight entering a round hole in a shutter to pass through a glass prism and fall on a screen. The resulting elongated image of the Sun, showing the same gradation of colours as the rainbow, he called a spectrum. In 1800 William Herschel studied the solar spectrum with the aid of thermometers and found the greatest effect beyond the red end, thus discovering infrared radiation. In 1801 Johann Wilhelm Ritter, studying the effect of solar radiation upon silver salts, found this action extending beyond the violet, thus discovering ultraviolet rays.
The first connection between spectral colour and wavelength appeared in 1802, when Thomas Young applied his wave theory of light to calculate the approximate wavelengths of the seven colours recognized by Newton. In 1814 Joseph von Fraunhofer modified Newton's experiment by substituting a narrow slit for a hole and a telescope for a screen. Under these conditions he observed the continuous spectrum of the Sun interrupted by hundreds of dark lines, still known as Fraunhofer lines. Fraunhofer constructed the first diffraction gratings, and with these he determined the wavelengths corresponding to many of these lines. Although Fraunhofer and others observed that certain bright lines in the spectra of flames seemed to coincide with dark lines in the solar spectrum, it remained for Gustav Robert Kirchhoff in 1859 to enunciate the generality of this phenomenon and to emphasize the fact that each species of atom has a uniquely characteristic spectrum.
<br>Fraunhofer was perhaps a good industrious capitalist, trying to make it in the lensgrinding business. He was probably more motivated by the irritating unwanted spectra around the edges of telescope images due to chromatic aberration, caused by the fact that blue light bends more than red light (due to its higher energy) when passing from air to glass to air.
The method used is achromatic lenses, the invention of which were Fraunhofer's chief concern at that time. Since Flint Glass and Crown Glass have different refractive indices, due to different chemistry, by making a sandwich of two half lenses of different glass, one can get some control over chromatic aberration that spoils a good view of a star.
But the thing that impresses me most about this guy was his craftsmanship. Here's a brief discussion of early grating manufacture, from http://snl.mit.edu/papers/Nanoruler-White-Paper3.pdf
Not without argument [2], the making of the first diffraction grating is often credited to the American astronomer David Rittenhouse (1732-1796) in 1785. He had a watchmaker cut very fine screws out of two pieces of small brass wire, and in the thread of these screws he laid hairs. Crude as it may be, this simple grating was sufficient to demonstrate the effect of light diffraction. Unfortunately, want of leisure made Rittenhouse pursue the idea no further, and his work, though published [3], attracted little attention at the time.
It was not until 1813 that the German physicist Joseph von Fraunhofer (1787-1826) reinvented the diffraction grating. A master instrument maker, Fraunhofer was dissatisfied with the quality of screw-wire-wound gratings and proceeded to build the first-ever grating ruling engine. A ruling engine, in a most simplistic description, is composed of two key parts: a carriage which holds the grating blank, and a very sharp tool, which is almost exclusively a diamond point, for burnishing the blank. During ruling, the diamond is dragged across the blankone of Fraunhofers first trials used a glass substrate covered with a thin layer of gold. When the ruling of one groove is complete, the carriage moves across by one grating period, (ie., the distance between the parallel scratches) under the guidance of a well-made leadscrew so the next groove can be ruled. Thus he produced gratings with much finer periods (ie., lines closer together) than previously achieved. With these improved gratings, he was able to accurately measure the absorption lines in the solar spectrum, now known as the Fraunhofer lines [4].
<br>So Fraunhofer was also a high class machinist.
By the way, here are some fine images of early gratings, to give you a hands-on feel/smell of the laboratory.
MIT professor George R. Harrison (1898-1979), the former head of the Spectroscopy Lab and later Dean of Science and one of the pioneers in the design of modern grating ruling engines, once wrote: No single tool has contributed more to the progress of modern physics than the diffraction grating, especially in its reflecting form [1].
Let me cut to the chase here, PeacfulNCurious, as I dearly hope you are I can't wish a better state on anyone, frankly.
The Atom, invisible to the naked eye by a factor of 10,000, CAN BE SEEN by various methods, if only indirectly. By virtue of the amazing accuracy of modern spectroscopes, thanks to pioneers like Fraunhofer, whose work even we laymen can sort of understand, we have fairly intimate knowledge of the composition of stars billions of light years away. We also know they are hurtling away from us at breakneck speeds, because all of the Fraunhofer lines (so well known each of these black lines are incredibly specific colors of photons which can't get out of the star's atmosphere because they are absorbed by one and only one (each color that is) energy level shift of an electron in one and only one element) the Fraunhofer lines, I say, are displaced towards the red end of the spectrum due to the Doppler Effect (Red Shift).
Questions for PeacfulNCurious:
--1. Curiousity
a. Are you curious about the natural world, about science, in areas where Faith doesn't collide at all?
b. Or only in areas where Faith appears to collide? That, you see, will tell you something,
not about Science, but about Yourself.
The great Pythagorean Motto: GNWQI SEAUTWN (GNOW-thi say-off-TONE) - "Know thyself",
is well worth obeying.
--2. Technology
a. Do you agree that technology has the power to extend our five senses far beyond what we are born with
b. Or is all that machinery untrustworthy?
--3. Method
a. Do you agree with Francis Bacon, and all those who came after in the adherence to what
is known as the Scientific Method, that confidence in conclusions, within limits, can be
achieved by means of "formulation and testing of hypotheses"?
b. Or do you secretly cherish the belief that "Nothing can really be known for sure by means of the five senses"
 
If you answered NO to the"a." part or YES to the "b." part of any of these questions, how can we possibly even communicate?
But if you answered YES to all the "a." parts, we definitely have a basis for further discussion.
Last question: Did you find this discussion of Spectroscopy interesting so far? Did it encourage you to seek deeper into the accumulated knowledge of mankind?
With genuine affection for you and all peaceful and curious people, I am a
ProudPrimate
PS. -- hope to continue this discussion, based on your input.
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Makes me think the whole world is going boxy!