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Does Quantum Mechanics Mean There Is A Finite Number Of Colours?


Omnifarious
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Forgive me if my reasoning is based on flawed logic and information. I am no physics expert.

As I understand it when light strikes an object the energy of the photons is absorbed by the atoms that make up the object. An atom's electrons can only orbit its nucleus at one level or another, nothing in between. When the atom absorbs the photon, the electrons jump up another level before going back down again. When this happens a new photon is emitted by the atom, it's energy dictated by the level the electron fell. Once this photon enters the eye we perceive it as a color prepending on how much energy it has. This is the photoelectric effect.

In other words, when I turn on the light in my living room, the light hits my walls and is absorbed by the atoms in the purple paint. They tune the light to their own frequency, in a sense dye the light, and eject it out into the world. This is how we not only see in colour but see at all.

Atoms that emit photons at very specific levels and only a finite number of levels, like cars have a finite number of gears and are either in one or another.

From this line of reasoning, I suspect that means there are a finite number of possible colors. That the spectrum we can see is quantized and not continuous. If light depends on the atoms in the physical matter to give them colour and atoms can only emit photons at a fixed set of discrete frequencies based on what element they are, then it would follow there are a fixed, finite number of colours, of shades that could possibly exist in the universe.

Is this true? Is every photon that comes off an object the same? Does this apply to monitor too? Is every colour we see part of a fixed pallet? Something predetermined and unchangeable? Like a cheap art program where you can only select from a list of pre-programmed colours? Is mixing paints, mixing atoms of various elements together make it continuous or is it still quantized and finite? It is said that colour is a wavelength and a wavelength can be any length and there can be an infinite number of differences between 2 points if you make the integer small enough. So there can hypothetically be any wavelength, any colour, any shade within the visible spectrum. But how can wavelengths be infinitely variable if they depend on atoms that can only emit wavelengths of certain colours? Yes I know that photons come from other places as well as atoms, but I'm talking about their colourization, once it leaves an object.

I write this because I have always been a very creative person and this idea is very upsetting to me. I have discussed this sort of thing with others but some of them were not very sympathetic or And if it's a vast but finite number of colours it would still upset me. Without going into how human perception works, could you answer my question? This is very important to me so please, if you answer, make the argument intelligent and open-minded. I know from personal experience that scientists sometimes talk about unproven things as if they are proven. I've never been able to pick up on that so if your answer is based on something that's still theoretical, please let me know because I tend to take things literally and think in absolutes. Someone talks about a theory like it's a truth and I can't help but assume it's already been proven beyond a doubt.

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Forgive me if my reasoning is based on flawed logic and information. I am no physics expert.

 

As I understand it when light strikes an object the energy of the photons is absorbed by the atoms that make up the object. An atom's electrons can only orbit its nucleus at one level or another, nothing in between. When the atom absorbs the photon, the electrons jump up another level before going back down again. When this happens a new photon is emitted by the atom, it's energy dictated by the level the electron fell. Once this photon enters the eye we perceive it as a color prepending on how much energy it has. This is the photoelectric effect.

 

In other words, when I turn on the light in my living room, the light hits my walls and is absorbed by the atoms in the purple paint. They tune the light to their own frequency, in a sense dye the light, and eject it out into the world. This is how we not only see in colour but see at all.

 

Atoms that emit photons at very specific levels and only a finite number of levels, like cars have a finite number of gears and are either in one or another.

 

From this line of reasoning, I suspect that means there are a finite number of possible colors. That the spectrum we can see is quantized and not continuous. If light depends on the atoms in the physical matter to give them colour and atoms can only emit photons at a fixed set of discrete frequencies based on what element they are, then it would follow there are a fixed, finite number of colours, of shades that could possibly exist in the universe.

 

Is this true? Is every photon that comes off an object the same? Does this apply to monitor too? Is every colour we see part of a fixed pallet? Something predetermined and unchangeable? Like a cheap art program where you can only select from a list of pre-programmed colours? Is mixing paints, mixing atoms of various elements together make it continuous or is it still quantized and finite? It is said that colour is a wavelength and a wavelength can be any length and there can be an infinite number of differences between 2 points if you make the integer small enough. So there can hypothetically be any wavelength, any colour, any shade within the visible spectrum. But how can wavelengths be infinitely variable if they depend on atoms that can only emit wavelengths of certain colours? Yes I know that photons come from other places as well as atoms, but I'm talking about their colourization, once it leaves an object.

 

I write this because I have always been a very creative person and this idea is very upsetting to me. I have discussed this sort of thing with others but some of them were not very sympathetic or And if it's a vast but finite number of colours it would still upset me. Without going into how human perception works, could you answer my question? This is very important to me so please, if you answer, make the argument intelligent and open-minded. I know from personal experience that scientists sometimes talk about unproven things as if they are proven. I've never been able to pick up on that so if your answer is based on something that's still theoretical, please let me know because I tend to take things literally and think in absolutes. Someone talks about a theory like it's a truth and I can't help but assume it's already been proven beyond a doubt.

 

It's a good argument and I like your reasoning, but the answer is no, the frequency of light/radio is linear no discrete incremental.

 

A photon of light is not generated simply by an electron changing valance bands, and by valance bands only, plus the balance band size if not fixed, it varies, that is the mechanism that produces thermal expansion for example. The valance band 'size' is a function of the energy state of the atom.

 

Also: valance bands are not the only possible states of electrons in atoms, hyperfine states are possible and common, that means it's not a 'quantum leap' between states with no in between. 

 

I think when a photon is absorbed or emitted by an electron the electron undergoes or has undergone a 'rate of change' change in both velocity (electric field) and rotation (magnetic field, indicated by Faraday rotation). As the electron undergoes both changes at the same time the electric field and the magnetic field are 'coupled' (they are produced by the one electron), and you get a photon of ElectroMagnetic radiation (light). 

 

But electrons are always moving, but generally the rate of change is relatively constant, so you just get 'EM noise' from the atom, and 'heat'. 

 

The amount of time it takes to go through that rate of change (of velocity and rotation), becomes the WAVELENGTH of the photon of light, it's the amount of time it takes for the electron to go through that motion.

 

When I talk about light being generated by driving an electron through an electric field change, and a magnetic field change such that the electron creates a photon. It is something every radio experienced electronics engineers knows to be a fact.

 

That is how you generate or receive light (in this case not visible light or radio, it's all the same thing, no different), you create a current (magnetic field) and a voltage (electric field) on a wire (antenna) in a particular way, at a particular rate of change that turns the current and voltage into electron motion over time that creates that coupled electric and magnetic field from the electrons motion change.

 

Same for receiving light (radio), the EM fields more the electron (excite it) and that in turn produces voltage and current in the wire that you can detect and measure (and listen to, or 'see'). 

 

Do we really know that magnetic fields and electric fields accelerate and rotate electrons (and makes them move) ??

 

Yes, we absolutely do know that, it is a fact, it's how a cathode ray tube works, the old style glass 'picture tube' on your own TV uses at different times electric fields and magnetic fields to accelerate electrons and to move them so they strike the screen where they are supposed too.

 

Faraday rotation is another thing, what Faraday rotation is is the change in polarization of light going through matter (interacting with electrons) when that matter is in a magnetic field.

 

Electrons respond to both electric fields and magnetic fields, they move in response to those fields, the same electron moves in two different ways (velocity and rotation) depending on being and electric field or a magnetic field, because it is the same electron with two different motions, you can consider the electric field and the magnetic field to be 'coupled' (coupled because it's from the same source, the electron).

 

I also do not like the idea of people talking about unconfirmed or unproven things as if they are fact, so I have tried to base my explanation fully on what is already well know and well understood. 

 

A radio engineer, or someone who knows how radio works, actually knows exactly how light works, how it is detected and created.

 

To create a photon you drive an electron through an electric field change and a magnetic field change at the same time, you voltage creates the electric field and current creates the magnetic field and you drive the electron through an acceleration and rotation. 

 

To detect a photon the photon impacts the electron, the electric and magnetic fields of the photon drives the electron through the same change and that in turn generates an electric field and a magnetic field, which is a voltage and current in a wire that you can detect.

 

As a side note:

 

Electrons are super cool! I means without them little guys we would be screwed, electrons (with photons they create) are the USB ports of matter!

 

(lastly) the E force and the M force are two different and distinct forces, they are NOT one 'EM force', although as they both do something to electrons they are of course related. But it is not one unified force.. 

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That the spectrum we can see is quantized and not continuous. If light depends on the atoms in the physical matter to give them colour and atoms can only emit photons at a fixed set of discrete frequencies based on what element they are, then it would follow there are a fixed, finite number of colours, of shades that could possibly exist in the universe.

 

You have to be saying that there is a finite number of ways to proportionally combine two or more different forms of physical matter?

 

But I would say 'yes' to your question because everything must be finite. 

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Thank you for your detailed reply.

Frankly some of it went beyond my knowledge, I'd like to break it down and ask you to clarify some things.

 

A photon of light is not generated simply by an electron changing valance bands, and by valance bands only, plus the balance band size if not fixed, it varies, that is the mechanism that produces thermal expansion for example. The valance band 'size' is a function of the energy state of the atom.

 

Also: valance bands are not the only possible states of electrons in atoms, hyperfine states are possible and common, that means it's not a 'quantum leap' between states with no in between. 

 

Just to be clear I know that photons don't just come from objects, they come from light sources. But I specifically wanted to talk about the ones that come of objects and get their colour in the process. Or are you saying those kind of photons are created by additional means?

 

Are valance bands the levels of electrons I was talking about?

 

I thought the bands were absolutely fixed, I was told that electrons are either in one band or another, never anything in between, that was a basic principle of quantum mechanics. How can this be if the bands aren't absolute in position?

 

When you say the bands vary, do you mean they shift in the atom? Or do they vary from atom to atom? I thought all atoms of the same element were exactly alike. That's why they always make the same colour.

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Thank you for your detailed reply.

Frankly some of it went beyond my knowledge, I'd like to break it down and ask you to clarify some things.

 

 

Just to be clear I know that photons don't just come from objects, they come from light sources. But I specifically wanted to talk about the ones that come of objects and get their colour in the process. Or are you saying those kind of photons are created by additional means?

 

Are valance bands the levels of electrons I was talking about?

 

I thought the bands were absolutely fixed, I was told that electrons are either in one band or another, never anything in between, that was a basic principle of quantum mechanics. How can this be if the bands aren't absolute in position?

 

When you say the bands vary, do you mean they shift in the atom? Or do they vary from atom to atom? I thought all atoms of the same element were exactly alike. That's why they always make the same colour.

I see where you're trying to go. Colours must be finite at some point. Not the same as Pi in which the last digit is infinite.

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Thank you for your detailed reply.

Frankly some of it went beyond my knowledge, I'd like to break it down and ask you to clarify some things.

 

 

Just to be clear I know that photons don't just come from objects, they come from light sources. But I specifically wanted to talk about the ones that come of objects and get their colour in the process. Or are you saying those kind of photons are created by additional means?

 

Are valance bands the levels of electrons I was talking about?

 

I thought the bands were absolutely fixed, I was told that electrons are either in one band or another, never anything in between, that was a basic principle of quantum mechanics. How can this be if the bands aren't absolute in position?

 

When you say the bands vary, do you mean they shift in the atom? Or do they vary from atom to atom? I thought all atoms of the same element were exactly alike. That's why they always make the same colour.

 

Apart from nuclear decay or reaction, or when you smash a proton at CERN, every photon (all light/radio) comes from electrons (it's also probably from electrons that produce light from nuclear reactions as well).

 

 

 

But I specifically wanted to talk about the ones that come of objects and get their colour in the process. Or are you saying those kind of photons are created by additional means?

 

This could get too complicated really quickly, and quantum mechanics does not really help in understanding.

 

Essentially, valence electrons balance out the energy state of the nucleus of the atom, so you have to think of it as an energy state not a fixed distance, so a valance band is the position for an electron that corresponds to the change of the nucleus. 

Electrons can exchange that position, in an atom, or it can share to different valence positions at the same time (covalent electrons).

 

An electron moving from one band to another can produce a photon (called 'atomic excitation'), and electron can also produce a photon by breaking away completely from the atom, that is called ionizing radiation. 

 

But most light is just created by an electron absorbing or releasing energy, without a valence change or the creation of an ion (atom with a missing electron).

 

So it does not really matter if there are fixed positions that electrons sit at normally, or if there is or is not 'nothing' in between, it is confusing for people when they are told of the 'quantum leap' that the electron does not exist between these bands, because we know by observation that electrons do in fact exist in between these states. The states themselves are fixed (by energy, not distance) and that fixed position is to balance the change of the atom.

 

But the energy states of atoms and electrons can vary, and it is continuously variable (no jumps), so the distance of the bands can vary (but the number of the bands cannot). 

 

So if that distance can vary then the velocity of the electron has to be able to change as well, if the orbit is larger the velocity will be higher.

 

Light is produced when an electron undergoes a change (two changes in fact, a velocity change and a alignment change). However long in time it takes for that change to happen is the length of the light produced. (the lights wavelength or colour). 

 

So in this terminology a 'band' is a region, or an area in which the electron can exist in in a stable state.

 

So it is within this band that gives us by far the most light we experience, so it is the transient or 'rate of change' of the motion within this band.

 

 

 

I thought the bands were absolutely fixed, I was told that electrons are either in one band or another, never anything in between, that was a basic principle of quantum mechanics. How can this be if the bands aren't absolute in position?

 

The bands are fixed, but they are still bands so they are not really fixed! (does that clear up everything LOL).

 

There are things in between as well, they just don't tend to stay there, but we use the fact that there is not 'nothing' in between in science (for example atomic clocks). So electrons CAN be in between.

 

So bands are fixed but variable, and you can have in between. 

 

But within that band things are not fixed, you can be high in the band or low in the band, how long it takes in time for the electron to transition from high to low or low to high in that band is the amount of time it takes to create the photon, the photon moving at constant speed then has a specific length (wavelength).

 

The wavelength of light is the 'colour' of light. The 'band' is continuously variable (within the band), so there is no fixed colour produced by this process, the colour of light is continuously variable.

 

IF, light was only produced by electrons jumping states (the quantum leap), then there is a very limited number of possible states of an atom, that would mean that there would be a very limited number of possible colours (frequencies) that matter would produce, but we don't see any limit to the number of colours. 

 

I don't think I'm being very helpful here, getting bogged down. 

 

Yes there are bands or states electrons exist in, and they are fixed (and quantized, there are whole numbers of them), but that does not help you, there are fixed band positions, but even within that position the electron can vary in position and velocity.

 

It is that change in velocity and position/alignment that generates an electric field and a magnetic field transient how fast that change happens determines the length (colour) of the light produced, or when light is absorbed the light creates that change in the electron.

 

When you shine a light on an object, the photon from you light moves the electron, because the electron moves a photon of light is produced and you see that light. 

 

I'm not helping I am sure: but try this.

 

Think about the electron in a atom being attached to the nucleus by a spring like the wheel of your car is attached to the car, you can have more than one spring (end to end) but the springs are quantized (only whole numbers of springs), but the spring has a range of motions it can be from fully compressed (and short) to fully stretched (and long), so there is a linear (continuous) number of positions that spring can be in between compressed and stretched. How long it takes to compress or stretch that spring determines the 'rate of change' of the springs length.

 

The colour of the light produced by the changing spring (electron attached) depends on the speed of the car and the size/length of the bump.

 

Sorry again, I don't know if I am being any help, I spent my life in engineering and science studying how light and matter interact, but science communication is not my strongest, and the concepts are a bit complex. I hope I helped and feel free to ask anything.. 

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Forgive me if my reasoning is based on flawed logic and information. I am no physics expert.

 

As I understand it when light strikes an object the energy of the photons is absorbed by the atoms that make up the object. An atom's electrons can only orbit its nucleus at one level or another, nothing in between. When the atom absorbs the photon, the electrons jump up another level before going back down again. When this happens a new photon is emitted by the atom, it's energy dictated by the level the electron fell. Once this photon enters the eye we perceive it as a color prepending on how much energy it has. This is the photoelectric effect.

 

OK

 

In other words, when I turn on the light in my living room, the light hits my walls and is absorbed by the atoms in the purple paint. They tune the light to their own frequency, in a sense dye the light, and eject it out into the world. This is how we not only see in colour but see at all.

 

 

OK
 
 
Atoms that emit photons at very specific levels and only a finite number of levels, like cars have a finite number of gears and are either in one or another.

 

 

Not quite. As you said, “a new photon is emitted by the atom, it's energy dictated by the level the electron fell”  When the electron drops  from a high energy level to a lower level, and a single photon is released, the energy E, of that photon is equal to the difference between those 2 energy levels. The frequency of the light is determined by f = E/h. Where E is energy and h is Planck’s constant.

 

But the frequency, f is not exactly defined by this equation because atoms are never in any exactly predictable energy state. Therefore, photon emission does not happen at an exact frequency, but within a narrow range of frequencies.

 

Also, the photoelectric effect isn’t the only way that photons are released by atoms. The photoelectric effect involves only bound electrons which have a particular amount of energy determined by their orbital position.

 

There is another phenomenon that involves the collision of a photon with a free electron*

 

*Free electrons or electrons which have low binding energy compared to the energy of the incident photon, and these will not be forced into a discrete transition as in the photoelectric effect, but instead react according to Compton scattering.

 

In Compton scattering, the shift in the wavelength of the photon, before and after its collision, is equal to Planck’s constant divided by the rest mass of the electron times the speed of light

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The bands are fixed, but they are still bands so they are not really fixed! (does that clear up everything LOL).

 

There are things in between as well, they just don't tend to stay there, but we use the fact that there is not 'nothing' in between in science (for example atomic clocks). So electrons CAN be in between.

 

So bands are fixed but variable, and you can have in between. 

 

But within that band things are not fixed, you can be high in the band or low in the band, how long it takes in time for the electron to transition from high to low or low to high in that band is the amount of time it takes to create the photon, the photon moving at constant speed then has a specific length (wavelength).

 

The wavelength of light is the 'colour' of light. The 'band' is continuously variable (within the band), so there is no fixed colour produced by this process, the colour of light is continuously variable.

 

 

Yes there are bands or states electrons exist in, and they are fixed (and quantized, there are whole numbers of them), but that does not help you, there are fixed band positions, but even within that position the electron can vary in position and velocity.

 

I'm trying to follow this. As I understand it, electrons are either in one band or another, in that way they are quantised. But they can exist anywhere within the band they occupy, in this way the electrons are not quantised. The space inside the band is not quantised. Plus bands can shift their positions and bands can vary from atom to atom, even if they are the same element. Is that right?

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I'm trying to follow this. As I understand it, electrons are either in one band or another, in that way they are quantised. But they can exist anywhere within the band they occupy, in this way the electrons are not quantised. The space inside the band is not quantised. Plus bands can shift their positions and bands can vary from atom to atom, even if they are the same element. Is that right?

 

yes, but it's not that electrons can be in one band or another, it is that the number of bands are whole numbers, plus the number of electrons in each band (in stable matter), is fixed, so that is again 'quantized', but for the higher bands the number of electrons can also vary, (in one particular band you might have 4 electrons, but you could also have 3. 

 

Semiconductors rely on that, it's called the 'electron-hole model', that is if you have a band that has room for 4 electrons but there is only 3 electrons in that band that 4th position is called 'a hole', it is a position that an electron can be in but it not.

 

But yes, the bands are 'fixed' in an energy band, and the number of electrons that can reside in that band is fixed, but the number of electrons actually in that band might be different from what can be in that band.

 

Electrons can just bands, to leave all the bands so you have a naked nucleus.

 

So the position of the bands can vary, and the position of the electrons in that band can vary (in position and velocity, or alignment and velocity). 

 

Electrons are quantized, you either have an electron or you do not, the number of bands are quantized, there is a whole number of bands (never a fraction of a band). 

 

BUT: electrons CAN exist between the bands, and can go from band to band, so the position or velocity and or alignment of the electrons is NOT quantized at all. And it's the position/alignment and velocity (rate of change) that produces or absorbs light. 

 

That is why there is an infinite number of possible values for the colour (frequency/wavelength) that light can be in, and they are not discrete numbers.

 

 

 

The space inside the band is not quantised. Plus bands can shift their positions and bands can vary from atom to atom, even if they are the same element. Is that right?

 

Essentially yes, but more accurately though would be to say the electron can shift it's position within the band, but the number of bands is fixed. And the number of bands depends on the atom. 

 

Electrons can also be in more than one atoms band, but none of that really matters.

 

As Ocean was saying, there is really no limit to the number of colours of light, and you could have light VERY long wavelengths (1 cycle every 10,000 years).

 

There is no theoretical upper limit to the frequency of light, but I believe there is a practical limit, that seems to be in the region of 1x10-15 meters.

 

 

Think about satellites orbiting the earth, the height of the satellite can vary some are in low earth orbit some are much further away, but they exist in a position in space that is 'allowed' by their velocity, you can have more than one satellite in that position, or you can have none. But you have a quantum number of satellites, and for electrons a fixed 'velocity range' that they can exist in. but their position in that orbit can vary, as can their velocity, and their rotation, none of those things are quantized. 

 

I'm almost tempted to get on a rant about popular science presenters about how they try to make these things seem astonishing an amazing, and making claims about things like electrons 'not existing' between the energy position valence bands, and all softs of other not justified claims.

 

If you hear someone say 'we only know down to the Planck length' ask them how close to the Planck length can they get. IF they even give you an answer they will have to admit (if they even know the length) that we can get NO WHERE even close to anything at that scale.

 

I do not even think they can explain how quantum mechanics is even a theory, if they think they can ask them what the theory states.

 

(See now I am ranting, sorry about that), I think you have it pretty good though.

 

That is also how big we believe an electron is and it is the wavelength of the highest frequency light (Gamma Rays), that's about 20 zero's longer that the Planck length, So I see no possible practical way to get light any or much higher than what we already observe.

 

And can get no where near anything even remotely close to the Planck length, to the degree that even using that term is completely meaningless.. 

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There are no gaps in the EM spectrum; it is thought to be continuous but it is probably within a finite range with wavelengths ranging from one Planck length up to the size of the universe. Whether or not you consider there are an infinite number of colors within that incredibly large, yet finite range, is more of a philosophical question than one that science can provide a definite answer for.

 

Remember that infinity itself is a concept, not a number. Rest assured there are more possible colors than you can ever count even if you could count them until the end of time but you can only see a very narrow range of them.

 

Electromagnetic Radiation Spectrum

 

Electromagnetic spectrum of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object. The electromagnetic spectrum extends from below frequencies used for modern radio to gamma radiation at the short-wavelength end, covering wavelengths from thousands of kilometers down to a fraction of the size of an atom. The long wavelength limit is the size of the universe itself, while it is thought that the short wavelength limit is in the vicinity of the Planck length, although in principle the spectrum is infinite and continuous.

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yes, but it's not that electrons can be in one band or another, it is that the number of bands are whole numbers, plus the number of electrons in each band (in stable matter), is fixed, so that is again 'quantized', but for the higher bands the number of electrons can also vary, (in one particular band you might have 4 electrons, but you could also have 3. 

 

Semiconductors rely on that, it's called the 'electron-hole model', that is if you have a band that has room for 4 electrons but there is only 3 electrons in that band that 4th position is called 'a hole', it is a position that an electron can be in but it not.

 

But yes, the bands are 'fixed' in an energy band, and the number of electrons that can reside in that band is fixed, but the number of electrons actually in that band might be different from what can be in that band.

 

Electrons can just bands, to leave all the bands so you have a naked nucleus.

 

So the position of the bands can vary, and the position of the electrons in that band can vary (in position and velocity, or alignment and velocity). 

 

Electrons are quantized, you either have an electron or you do not, the number of bands are quantized, there is a whole number of bands (never a fraction of a band). 

 

BUT: electrons CAN exist between the bands, and can go from band to band, so the position or velocity and or alignment of the electrons is NOT quantized at all. And it's the position/alignment and velocity (rate of change) that produces or absorbs light. 

 

That is why there is an infinite number of possible values for the colour (frequency/wavelength) that light can be in, and they are not discrete numbers.

 

 

Essentially yes, but more accurately though would be to say the electron can shift it's position within the band, but the number of bands is fixed. And the number of bands depends on the atom. 

 

Electrons can also be in more than one atoms band, but none of that really matters.

 

As Ocean was saying, there is really no limit to the number of colours of light, and you could have light VERY long wavelengths (1 cycle every 10,000 years).

 

There is no theoretical upper limit to the frequency of light, but I believe there is a practical limit, that seems to be in the region of 1x10-15 meters.

 

I'm hearing that bands and electrons are fixed but they are also not? Are there some aspects that are quantised and some not? and are the ones that are finite in possibilities?

By the way, when I was talking about the possibilities of light, I wasn't necessarily talking about it's wavelength going on forever. But rather weather infinitely variable in it's length.

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I'm hearing that bands and electrons are fixed but they are also not? Are there some aspects that are quantised and some not? and are the ones that are finite in possibilities?

By the way, when I was talking about the possibilities of light, I wasn't necessarily talking about it's wavelength going on forever. But rather weather infinitely variable in it's length.

 

The number of bands is quantised, and yes, they are finite in possibilities. 

 

I know it's a bit confusing, if you think about the 'solar system' basic model for atoms, you can think of a hydrogen atom as being a proton with an electron orbiting around it. 

 

The orbit of the electron is some distance from the proton and is a 'band' of values, also the distance of that entire band can vary in distance from the proton (depending on factors like heat etc). 

 

BUT for a hydrogen, there is ONLY one band, plus there is a whole number of electrons that can occupy that band.

 

The total number of electrons in an atom is basically how many protons are in the nucleolus of the atom, such as 1 for hydrogen and 2 for helium. 

 

But a band can only have so many electrons in it, if the atom has lots of protons, it will have many bands each one filled with the required number.

 

So the number of electrons in a band is fixed, and the number of bands are fixed. 

 

Light is produced by the movement of an electron within it's particular band, not by it jumping bands, but also that the entire band itself can be in a different position is shown by increase in frequency (colour) of light when something gets hotter for example. (also with thermal expansion).

 

When matter gets hotter the bands get further away from the nucleus the band is still the same, there is still only a fixed number of them, but it's bigger. The actual width of the band itself is probably the same. But the entire atom is larger.

 

 

By the way, when I was talking about the possibilities of light, I wasn't necessarily talking about it's wavelength going on forever. But rather weather infinitely variable in it's length.

 

 

Yes, I know that, but someone else was commenting on frequency (colour) range.. 

 

So, yes, there is an infinite number of colours between red and slightly blue red. 

 

An engineer would say it is linear, a mathematician would say it is a continuous function, as opposed to a digital or discreate function, a discreate function is the number of electrons, and the number of bands, the linear function is the diameter of the bands.

 

The other linear function is the position and alignment and velocity of the electron within that band, that variability is what gives us the continuous spectrum of colours and frequencies of light. 

 

So light is produced by the electrons jiggling around within their own stable band within stable matter, not from moving to a new band or leaving a band at all, that is more about chemistry and chemical reactions than the production of light. But light CAN break the electron bond and ionize the atom. But for visible light and for the colours and frequencies of light (and radio), it is the motion of the electrons in the stable matter, in their stable bands.

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I'm hearing that atoms can change the light they emit when they get hot or have chemical interactions.

Is that what makes the spectrum continuous? And is it the only thing?

The paint on my walls, heating it or creating a chemical reaction would shift it but what about when it's just there at normal temperatures? Is the continuous spectrum only available to it that way or could you have an object able to give of any wavelength on it's own? 

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I'm hearing that atoms can change the light they emit when they get hot or have chemical interactions.

Is that what makes the spectrum continuous? And is it the only thing?

The paint on my walls, heating it or creating a chemical reaction would shift it but what about when it's just there at normal temperatures? Is the continuous spectrum only available to it that way or could you have an object able to give of any wavelength on it's own? 

 

The colour that something appears to be is a function of the atomic and chemical structure of the thing you see, and what you see is the colour that the thing is NOT absorbing, a leaf is green because it is absorbing all the other colours and not green, but that is more a function of how bound and fixed the electrons are in the matter. 

 

To to get matter to emit high frequency light you need to give the electrons enough energy to go through a change in a shorter amount of time, so that is often done by temperature. You might see your fan heater element glowing slightly red, that is lower frequency light (red and infrared felt more as heat). 

 

But as you increase the energy and temperature, the frequency of the light will get higher, and you will get white light with the full spectrum of colours, heating the wall is not going to make any real difference to the colour of the light it reflects, but will change the colour of the light it emits by itself. It's called 'colour temperature'. 

 

But different types of matter absorb light at different frequencies, (that's how a mass spectrometer works) and it's used in astronomy. 

 

But if green light falls on a leaf, that colour of light is not used by the plant for energy, so it is not absorbed, and it is not converted into heat (and lower frequency light, like infrared). Instead the green photon strikes an electron, that electron jiggles a bit within it's band and in it's atomic structure, and that electron emits a green photon, that you see as reflected green light.

 

In something transparent, (like glass), the electrons are probably in very narrow bands that do not allow the light to jiggle at all, so there is little or no absorption or emission, although the light still does slightly interact with the electrons. 

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