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  1. #1 Glass 
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    How does light manage to travel through glass and emerge at nearly the exact same spot on the other side? I know that most glass is afflicted by various deformations in its structure, but some high grade glass, such as that which composes my computer desk does not possess any notable light distorting attributes. It seems as if light moves through too many atoms to not be effected....do the atoms essentially ignore the photons? You could say that they only pass through the vast distance between the electron orbits and the nucleus...but then that would apply to all matter; unless...there is some type of field that normally catches the photons while going through the empty space that is not present in glass. Perhaps the chemistry of the components conveying the glass form a type of comb filtering of their fields, rendering the space in between unaffected.


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  3. #2 Re: Glass 
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    Quote Originally Posted by Cold Fusion
    How does light manage to travel through glass and emerge at nearly the exact same spot on the other side? I know that most glass is afflicted by various deformations in its structure, but some high grade glass, such as that which composes my computer desk does not possess any notable light distorting attributes. It seems as if light moves through too many atoms to not be effected....do the atoms essentially ignore the photons? You could say that they only pass through the vast distance between the electron orbits and the nucleus...but then that would apply to all matter; unless...there is some type of field that normally catches the photons while going through the empty space that is not present in glass. Perhaps the chemistry of the components conveying the glass form a type of comb filtering of their fields, rendering the space in between unaffected.
    I was taught that light when it hits the surface of glass, is slowed, and then accelerated. So that it carries an exact picture of what it was carrying before it hit the glass. I was taught that it was electrons carrying the light.



    If you took a look at this link you can see that electrons are doing everything just fine. Until we get to light. Light is something a lot can see and a lot of people have a lot of hands on experience with.
    When light was just electrons a lot of people started to hypothesis that these little electrons were working just like Universal Scientists said they were. From working with light they determined that they had no weight or mass.

    And that electron events were velocity driven. Things became very easy to understand. And that is when the government hired poor scientists to hide real science.

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    And that is when the government hired poor scientists to hide real science.
    And all the governments of the world did this? Could you open up a thread to discuss your conspiracy delusions and leave proper threads alone please?

    Anyway AFAIK, the absorption of photons by a medium depends on the excitation energy of valence electrons. If this energy band excludes most or all of the visible spectrum, little or nothing gets absorbed and the path is undisturbed. In liquids some of the energy can go into rotating water molecules, absorbing it thus and adding to the internal kinetic energy of the medium. Also, I think there is a difference between the atomic structures of plain glass and crystal. I think crystal is, as the name suggests, crystalline, so the molecules are lined up in a grid that provides a greater chance for photons to travel through the medium without encountering a molecule. Obviously the thicker the medium, the less the chance of a photons to escape unscathed becomes. You could take a look at these subjects: Mean free path, Beer-Lambert law, Attenuation coefficient. I hope you can find your answers there or in the links they include. :wink:
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    Quote Originally Posted by KALSTER
    And that is when the government hired poor scientists to hide real science.
    And all the governments of the world did this? Could you open up a thread to discuss your conspiracy delusions and leave proper threads alone please?

    Anyway AFAIK, the absorption of photons by a medium depends on the excitation energy of valence electrons. If this energy band excludes most or all of the visible spectrum, little or nothing gets absorbed and the path is undisturbed. In liquids some of the energy can go into rotating water molecules, absorbing it thus and adding to the internal kinetic energy of the medium. Also, I think there is a difference between the atomic structures of plain glass and crystal. I think crystal is, as the name suggests, crystalline, so the molecules are lined up in a grid that provides a greater chance for photons to travel through the medium without encountering a molecule. Obviously the thicker the medium, the less the chance of a photons to escape unscathed becomes. You could take a look at these subjects: Mean free path, Beer-Lambert law, Attenuation coefficient. I hope you can find your answers there or in the links they include. :wink:
    Wow, why don't you go and open up a thread for your conspiracy delusions. It can be a discussion about the honesty, and integrity of law makers on earth. Heck you can call for the burning of American history, what is left of it. It shows nothing but total corruption from law makers, accept when men like Benjamin Franklin and George Washington team up.

    Did you ever see the link to the last Universal Scientist? Why don't you go and find the rest of them for me. That last Universal Scientist is where Einstein claimed to get his information that a bomb might be made from Uranium Isotope.

    Eat some spinach or something. Watch Rocky. Do something.

    Just out of curiosity is radiant heat still electrons?

    Because if radiant heat is electrons, they penetrate a silicon wafer. That has a high dielectric strength. Yet no light is emitted.

    In my teachings electrons had no mass or weight either. Neither did matter.

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    William McCormick
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  6. #5  
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    Quote Originally Posted by William McCormick
    Wow, why don't you go and open up a thread for your conspiracy delusions.
    Speak for yourself, bozo! You’re the one who is hijacking Cold Fusion’s thread here!
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    Quote Originally Posted by JaneBennet
    Quote Originally Posted by William McCormick
    Wow, why don't you go and open up a thread for your conspiracy delusions.
    Speak for yourself, bozo! You’re the one who is hijacking Cold Fusion’s thread here!
    Jane I do not hijack, I attempt to highlight poor science. I have a lot of work here.

    I like the avatar, it captures the inner you.

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    William McCormick
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  8. #7  
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    Quote Originally Posted by William McCormick
    Jane I do not hijack, I attempt to highlight poor science.
    You go round threads hijacking them by spewing your pseudoscientific spam all over them, that’s what you do! You are a troll (albeit a subtle one). Please do everyone a favour and GTFO!
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    You go girl!

    I don't understand why william is ignored by moderation. :? He double and triple posts all the time, posts a million dubious links to his website, that almost smell like spam, preaches psuedoscience....as fact, ignores good advice, has no shame, and an apparent agenda for chaos. Dude, go away!!
    Chance favours the prepared mind.
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    although I agree, since he started a really hard-to-understand discussion on a simple question of mine, I have to say we are all of us right now spamming someones thread , so lets leave the critic talk about "William McCormick" for what they are, and let him take a conclusion from the posts already posted.
    ow and Glass is a liquid, so that makes it easier for light to pass through, but a few posts before me this was already said. :wink:
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    Glass is a liquid
    I know this is a common misconception, but in truth it is not a liquid and I apologise if you think that is what I was saying in my post. :wink:

    This is from the Wiki Site on Glass:

    "Ordinary glass is prevalent due to its transparency to visible light. This transparency is due to an absence of electronic transition states in the range of visible light. The homogeneity of the glass on length scales greater than the wavelength of visible light also contributes to its transparency as heterogeneities would cause light to be scattered, breaking up any coherent image transmission".

    You'll also find a piece on the misconception that glass flows over time. It is an amorphous solid and a supercooled liquid; it could technically be qualified as a liquid due to its lack of a first-order phase transition, but it exhibits zero flow over time.
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    How can photons rotate water molecules?
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

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  13. #12  
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    Quote Originally Posted by Cold Fusion
    How can photons rotate water molecules?
    From the Wiki sites on Permativity and Diatomic molecule:

    "Quantum-mechanical interpretation

    In terms of quantum mechanics, permittivity is explained by atomic and molecular interactions.

    At low frequencies, molecules in polar dielectrics
    (like water I think) are polarized by an applied electric field, which induces periodic rotations. For example, at the microwave frequency, the microwave field causes the periodic rotation of water molecules, sufficient to break hydrogen bonds. The field does work against the bonds and the energy is absorbed by the material as heat. This is why microwave ovens work very well for materials containing water. There are two maxima of the imaginary component (the absorptive index) of water, one at the microwave frequency, and the other at far ultraviolet (UV) frequency.

    At moderate frequencies, the energy is too high to cause rotation, yet too low to affect electrons directly, and is absorbed in the form of resonant molecular vibrations. In water, this is where the absorptive index starts to drop sharply, and the minimum of the imaginary permittivity is at the frequency of blue light (optical regime). This is why water is blue, and also why sunlight does not damage water-containing organs such as the eye.

    AND

    For microscopic, atomic-level systems like a molecule, angular momentum can only have specific discrete values........This spacing between the lowest two rotational energy levels of O2 is comparable to that of a photon in the microwave region of the electromagnetic spectrum.
    (I am guessing that, among others, the same is true for H<sub>2</sub>O )"
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    Quote Originally Posted by KALSTER
    Glass is a liquid
    I know this is a common misconception, but in truth it is not a liquid and I apologise if you think that is what I was saying in my post. :wink:
    I don't know who to believe, because in a museum here in holland I was told that the first electric machines (they have the largest I believe) were malfunctioning because the glass flowed away. I heard there that the Glass that we use today has a very small amount of Hg in it, that would make the glass solid.
    Furthermore one of my teachers at school once told me he had seen different thicknesess in shards of glass from the same sheet. the sheet of glass had been standing vertically and had broken when someone had put his bike against it. the top was thin as a sheet of paper and the lower end was more than three times as thick as it should have been.

    now as I said. I do not know who to believe, but this is what my teachers tell me..

    I'm searching for the truth.. - again..
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    Quote Originally Posted by Psamathos
    I don't know who to believe, because in a museum here in holland I was told that the first electric machines (they have the largest I believe) were malfunctioning because the glass flowed away. I heard there that the Glass that we use today has a very small amount of Hg in it, that would make the glass solid.
    Furthermore one of my teachers at school once told me he had seen different thicknesess in shards of glass from the same sheet. the sheet of glass had been standing vertically and had broken when someone had put his bike against it. the top was thin as a sheet of paper and the lower end was more than three times as thick as it should have been.

    now as I said. I do not know who to believe, but this is what my teachers tell me..

    I'm searching for the truth.. - again..
    From the Wiki page on Glass:

    "Behavior of antique glass

    The observation that old windows are often thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a matter of centuries. It is then assumed that the glass was once uniform, but has flowed to its new shape, which is a property of liquid. The likely source of this unfounded belief is that when panes of glass were commonly made by glassblowers, the technique used was to spin molten glass so as to create a round, mostly flat and even plate (the Crown glass process, described above). This plate was then cut to fit a window. The pieces were not, however, absolutely flat; the edges of the disk would be thicker because of centripetal force relaxation. When actually installed in a window frame, the glass would be placed thicker side down for the sake of stability and visual sparkle.[23] Occasionally such glass has been found thinner side down or on either side of the window's edge, as would be caused by carelessness at the time of installation.

    Mass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets were cut into smaller window panes with nonuniform thickness. Modern glass intended for windows is produced as float glass and is very uniform in thickness.
    "

    There is more to be found under the quoted heading with further explanations. :wink:
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  16. #15  
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    Quote Originally Posted by William McCormick
    Jane I do not hijack, I attempt to highlight poor science. I have a lot of work here.
    You wouldn't recognise any form of science if it jumped up and bit you in the proverbial. I am growing bored of issuing you warnings publicly and privately. Shape up, or ship out. Understand?
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by William McCormick
    Jane I do not hijack, I attempt to highlight poor science. I have a lot of work here.
    You wouldn't recognise any form of science if it jumped up and bit you in the proverbial. I am growing bored of issuing you warnings publicly and privately. Shape up, or ship out. Understand?
    Is radiant heat still electrons?

    Because if it is, still electrons, it passes through a very dielectric, mirror computer wafer. And does not even stop to heat the wafer. You cannot see light through the wafer.

    If it is photons, according to multi subatomic particle people, it emits no light. And passes through a computer wafer.



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    Quote Originally Posted by Psamathos
    I don't know who to believe, because in a museum here in holland I was told that the first electric machines (they have the largest I believe) were malfunctioning because the glass flowed away. I heard there that the Glass that we use today has a very small amount of Hg in it, that would make the glass solid.
    I am sorry but your teacher is full of it. There is the possibility that some glass they used in ye olden times just melted due to thermal load when a soft soda-lime-silica (SLS)-glass was used. "Soft" in glass-speak means low melting point and not low Vickers/Brinell/Knoop-hardness. And I still have to find a industrially used glass that has a mercury compound in it. And even if someone for whatever moronic reason puts some mercuric oxide in the batch it would most likely behave like Lead-oxide i.e. as a network modifier that actually lowers melting point, chemical durability and mechanical strength.

    Quote Originally Posted by Psamathos
    Furthermore one of my teachers at school once told me he had seen different thicknesess in shards of glass from the same sheet. the sheet of glass had been standing vertically and had broken when someone had put his bike against it. the top was thin as a sheet of paper and the lower end was more than three times as thick as it should have been.

    now as I said. I do not know who to believe, but this is what my teachers tell me..

    I'm searching for the truth.. - again..
    If this was really the case then this was due to poor process controll during sheet glass production and shure as hell had nothing to do with glass "flowing" after it cooled below it's working temperature. Just to give you an example: at it's "working point" a SLS-glass has a viscosity of around 10^4 poise at a temp of roughly 1200 to 1300°C. 10^4 poise can be compared with the viscosity of cold honey. The annealing point of such a glass is around 500°C the viscosity is already at 10^14 poise. A viscosity of 10^14 poise can only be measured with special techniques e.g. suspending a weight on a glass fiber and measuring the elongation of this fiber. And for all practical purposes this is allready solid, no flowing under it's own weight can be observed at this temp. Now extrapolate the viscosity curve down to room temp and you'll end up with something like 10^28 to 10^30 poise. Around 14 to 16 ORDERS OF MAGNITUDE higher than at the annealing point. No flow whatsoever will happen. Period.
    The whole bull about glass resembling a supercooled liquid comes from the 1920ies and is outdated as hell.
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    okay, now I see.. I am still waiting for a reply from the museum, because of course this I want to have more than one source for my information. Anyway, thanks for the info :wink:
    now ... about that light-through glass that should have been the subject of this topic... :wink:
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  21. #20  
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    Quote Originally Posted by Psamathos
    okay, now I see.. I am still waiting for a reply from the museum, because of course this I want to have more than one source for my information.
    Museums, unless for working scientists (like the Natural History Museum in London), may not contain enough expertise to answer a technical question like that.

    Simpler to refer to a classic like Professor J E Gordon's The New Science of Strong Materials where you will get chapter and verse on the differing solid state structures of glasses and crystalline substances and why both alike are solids anyway.
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