Nagging questions (AMA)

[SasQ 1,376]

I've seen recently several threads appeared with different kinds of questions, more or less serious/strange/etc., but I guess all simply coming out of curiosity. I asked some myself, too. (Guilty.)

 

This has got me an idea:

 

I bet anyone of you has some nagging questions, which you carry in your head since long time, and no one ever could answer you to them. Right? E.g. why is there that white crayon in the crayon box? Or why is the sky blue at day, red at sunset, and black at night? Or why are we being forced to remove irrationality from the denominator of our fractions in math classes? Or where do we know the digits of the number pi from? Or why is the heat flowing from hotter to colder objects and not the other way around? Or what is time anyway? Or how can a high-jumper jump higher than his own height? Or why are some thick objects transparent, when some other, thinner object are not? And lots & lots of other questions, I guess...

 

But I also noticed that many of these questions I can answer (I'm a smart pony after all, if you didn't notice ). And I guess that many of you could know the answers for some other people's nagging questions, too. So why don't we just make a bargain? 

 

I like solving problems, and I'm unstoppable in my drive for knowing the answers. This way I found (or discovered) answers to many of the nagging questions from my childhood and adult life. And many people come to me and start asking more questions as soon as they notice I can answer them.

 

That's why I'm curious of your nagging questions. What bothers you from your earliest childhood to this day? Do you have some questions which no teacher in your school could answer? Or something you always wanted to understood but no one could explain it to you in a comprehensible manner? (People tell me that I have a talent for simplifying things and explaining in a comprehensible manner, so you can count on me ). Please ask your questions here in this thread. And if you see a question of your peer you think you know the answer, feel free to help your friend I'll try to answer them too, if not here, then I'll try to write a whole article about that on my website if I find something interesting enough (There are some interesting articles already you can check out. E.g. about solving quadratic equations in your head, using simple geometry instead of the dreaded quadratic formula.)

 

What do you think of this idea?

And don't forget to post your nagging questions

Edited February 19, 2014 by SasQ

[Scootalove 10,689]

I like this idea!

 

Here's my nagging question: I've always wondered, how weight is distributed on a scale in Math but I've never found the answer to it. So, how is weight distributed on a scale in Math?

[Doctor XFizzle 8,669]

If we were able to send a man to the moon back in the darn 60s, why haven't we done it since 1972 with much better technology and advancement?

 

We should have like a colony on the moon by now.

[PsychedelicPony 440]

Can you explain to me Quantum Physics, I understand that is something to do with randomness, but what does it actually mean in terms of real life application?

[SasQ 1,376]

Wow, you're quick

 

@@Scootalove, can you be more specific? I'm not sure I understand your question correctly. What weight do you mean and what scale? And how is it related to Math?

 

@@Doctor XFizzle, interesting question. Unfortunately I don't know about any NASA workers lurking at these forums, so you probably won't get any convincing answers. (Especially that you cannot count on it even from the NASA officials.) But if we really ever landed on the Moon (there are some theories that the whole event has been forged, you know, slow-motion video playback to simulate lower gravity, the U.S. flag waving by the wind which couldn't happen on the Moon etc.), I suppose it happen in the past because U.S.A. and Soviet Union has been competing about who will get there first, so they did it at all cost. Now, when the game is over, there's not much a reason to go to the Moon (been there, seen it, no cheese there), and another such a mission would cost lots of money which, at the time of financial crisis, could be better spent. Moreover, when you look closer at our spacecraft technology, it's pretty old and quirky: we can leave our Mother Earth only in a big metal can with a huge fire underneath. Extraterrestrials are surely laughing their green shit out when watching our equipment 

 

Can you explain to me Quantum Physics

 

Sure I can! This is my favorite subject after all

 

I understand that is something to do with randomness, but what does it actually mean in terms of real life application?

 

This is how Quantum Physics is always presented by the scientists and "scientific" media: as something beyond our comprehension, full of absurd weirdness, randomness, chaos, hidden dimensions, particles being at different places at the same time, and other "quantum miracles" happening when you go down into the "quantum realm", as they call it (the atomic scale). And that there are limits to our comprehension which we will never be able to cross. This trend of scientific decadence has been started by Niels Bohr and his Copenhagen cullies, and it persists to this day. But from my own studies in this subject I can tell you that they couldn't be more wrong!

 

Quantum Physics has nothing to do with randomness (nor point particles flying around, to be honest), and it isn't limited only to atomic scale. (Actually you can observe quantum effects in human scale, too, and you don't need any expensive laboratory equipment for that.) All the confusion comes from misunderstanding some experiments and taking wrong assumptions on the start, which then avalanche on everything which follows, causing weird paradoxes and misunderstanding. Nature is simple, and it doesn't hide from us. You can understand it if you study it carefully. If you drop the false assumptions, all the paradoxes are gone, and you can then understand Quantum Physics with ease 

 

So what are those wrong assumptions? The biggest culprit is this: point particles. When you assume they exist, you're already in the bushes, because there are no point particles. Matter is made of waves, and only waves. Nothing else is needed. These waves can sometimes appear to us as if there were some particles there, but this is just appearance. One of the forefathers of Quantum Physics (the real one), Erwin Schrödinger, once said:

 

"What we observe as material bodies is nothing more than shapes and changes in the fabric of space.

Particles are only shaumkronnen (foam on water)."

 

He meant that space itself can bend and ripple, similarly to a water surface, creating wave motions, which we perceive as matter, light, fields and forces. We cannot see the "water" (space) and its motion (waves) directly, we can only observe the foam, which may appear to us as particles. But there are no particles flying around in there. We can imagine that there are some particles, but then we are in trouble, because then you will observe that those particles can appear out of nowhere, or be at different places at the same time, and you need to bring in statistics and probability to describe them, but this will lead to strange paradoxes and absurd theories. You don't need all of that to understand Quantum Physics.

 

OK, so let me now explain you Quantum Physics in a simple way.

 

At the deepest level, there's only Space. The space has elasticity: it can bend and ripple, similarly to water surface on a lake, creating waves. Those waves are disturbances in the perfect balance, and they can transmit information from one place to another, without taking the Space with them. This is the only true motion possible (and only one needed), because it leaves the Space where it is, and can transmit information from place to place nevertheless. Always with the speed of light, c.

 

In each medium, waves have a constant speed of propagation: they cannot go faster than the speed of light; but they cannot go slower either!    So how can we ever see objects slower than light in our everyday life? That's because waves can mix. If they have different wavelengths (distances between subsequent crests, or between troughs), they can produce "beats": they form "wave packets" of waves of varying amplitude, which themselves can move with a slower speed than their component waves, similarly to a Mexican wave in a stadium. (Fun fact: they can also go faster! But that's whole another story...) This is called "group velocity" of the wave packet, as opposed to the "phase velocity" of its component waves. (The phase is just an information about where we are in the whole cycle. As with phases of the Moon.)

 

A single wave with single frequency (or "pure tone") repeats itself indefinitely in every direction, so it doesn't have any distinct points which you could say: "The wave is here."

But once you mix in more waves with different wavelengths, they start forming "wave packets", and they're getting more and more localized in space, because where all those component waves meet in their crest, all these crests reinforce each other, producing a bigger crest (same with two or more troughs). And where the crest and trough meet, they cancel each other out and we have flat line. But since these waves have all different frequencies, they cannot keep in sync with each other too often, and there won't be many places where all those crests meet. Here's how it looks like:

 

 

Now you can roughly estimate where the wave packet starts and where it ends. But there's a downside: the more wavelengths you mix in, the lesser you know about which particular wavelength is there. The truth is: they're all there. In the same way there can be lots of different frequencies in the radio signal at the same time. Why is it important? Because it tell us something about our culprits ("particles").

 

I hope you already noticed that those "wave packets" are somewhat similar to what is often described as "particles". They can move, they have certain location in space, and they can carry some information: the wavelengths mixed into it. And those properties of waves can be directly translated into our "physical" notions, such as energy, momentum, mass, charge etc. Here's how:

 

You might have heard that red light has longer wavelength than blue light. And that blue light is more "energetic" than red light: you need more energy to produce blue light, and you can transmit more energy with it to some receiver. That's right: the faster the wave wiggles back and forth, the higher is its energy. The mathematical relation between them, as found by Max Planck, is as follows:

   E = h f

where E is energy, f is frequency (how fast it wiggles), and h is just a number, called Planck's constant, which allows us to translate from units of frequency (Hertzs) to units of energy (Joules). It plays a similar one as a conversion factor between miles and kilometers, or between Farenheit and Kelvin temperature scales. Don't let the physicists mislead you: Planck's constant is not some mysterious property of Nature; it is an artifact which comes solely from our arbitrary choice of units! If we were using different units for energy and frequency, the value of this constant would also differ. We can even choose our units in a "natural" way, so that this constant will turn into 1 and disappear from the equation. And then you will see that energy and frequency are actually different names for the same phenomenon.

 

Same is with momentum. But instead of in time, it takes place in space. The more wavelengths can be packed in one unit of space (e.g. an inch), the "denser" the wave is, and the harder it would be to change its motion. That's why the wavelength (actually its inverse, which is officially called "wave number" from historical reasons, but I like to call it "spatial frequency", because it tells how many crests you encounter when you move along the wave by one unit of space, so it is analogous to wave frequency in time which tells how many impulses you hear in one unit of time) could be mapped into momentum. Here's the formula for it, found by Louis de Broglie:

  p = h / ? = h k

where p is momentum, ? (Greek letter "lambda") is wavelength, k is wave number (or frequency in space) and h is again Planck's constant. See how it pops out in both contexts? It's a universal conversion factor between wave properties and Classical Physics notions such as energy and momentum And notice the symmetry: Frequency in time is energy, when multiplied by Planck's constant. Frequency in space (wave number k) is momentum, when multiplied by Planck's constant. They're all just different names for these frequencies, and are measured in different units (less natural). It's all from historical reasons, because when we discovered momentum and energy, we didn't know yet that there are any waves hiding behind all these phenomena.

 

Now, recall the wave packets.

As I said, the more different wavelengths you mix together, the more "short" (localized in space) the wave packet becomes. Sounds familiar?   Yes, this is what we know as Heisenberg's Uncertainty Principle! It's not some limitation to our measuring devices or senses; it's not Nature hiding from us or plotting against us to deceive us; it has nothing to do with randomness. It's just a simple observation that waves are extended in space. They don't occupy one particular place (or point) -- some part of the wave can be here, the other part there... and trying to fit it into some abrupt boundaries is against its nature. It's like you were trying to tell precisely where the elephant is: you cannot point any particular place, because the elephant is not a point! It occupies some region of space. You can tell that the elephant starts roughly here (where his trunk is), and ends roughly there (where his tail ends). Same is with waves: you cannot tell exactly where the wave is, because it occupies some region of space. The more wavelengths you will mix, the better you'll be able to bound this region, because the wave packet gets shorter. But the downside is that now you cannot tell its momentum with equal precision, because the more different wavelengths are there, the less you can point at any particular wavelength. That's because this is a mix! They're all there at the same time! In the same way as there are multiple frequencies in the radio signal, or multiple colors of light mixed in the white light from the Sun. But you don't use probability to tell what are the chances to find any particular color there, don't you? You just use the glass prism to decompose the white light into its spectrum (or rainbow, as Pegasi call it ). All these colors are contained there. In the same way, all these wavelengths are there in the wave packet, and since all of them can be seen as different momenta, the wave packet doesn't have any particular momentum, but a whole bunch of them. Same with energies (frequencies). Heisenberg's uncertainty is a simple result of how waves mix together. There's nothing mysterious in it, and Wave Physicists knew this rule years before.

 

There's a funny story about Heisenberg's Uncertainty involving Niels Bohr and Charles Townes, the inventor of laser:

When Townes proclaimed that he invented laser, Bohr came to him particularly to tell him he's wrong, and his laser cannot work, because it breaks the Uncertainty Principle of his Copenhagen colleague, Werner Heisenberg. When he came there, and Townes has shown him a working prototype of the laser, Bohr retreated strategically and he never returned to this subject again.

What is the moral of this story?

When you understand wave phenomena properly, you can build laser, no matter what your fellow Physicists with their absurd theories tell about it So study wave phenomena and you will start noticing the simplicity behind Quantum Physics. All complexities of Quantum Physics come from misunderstanding of these simple wave phenomena.

 

There is still a lot of interesting things to say about Quantum Physics, e.g. the infamous Double Slit experiment, or quantum effects (teleportation, tunneling, faster-than-light communication etc.), why scientists think the "particle" can be at different places at the same time, how atoms work and how they exchange energy as light. But I'll leave it to some other time. I think what I wrote above is a good starting point, and I'll stop here to not overtake the thread. Other people have questions too, and I never meant this thread to be a one-actor show   If you have some further questions, though, feel free to ask. You can always start a separate thread, or send me a PM (however there might be other people interested in it, so maybe it's better to leave it public).

Edited February 19, 2014 by SasQ

[PsychedelicPony 440]

Thanks, I think I understood most of that.

 

 

Follow up question, how does Schrodinger's Box fit in to all that. That we can't know if there is a cat in there or not and to open the box would ruin the data. Is this because of the fact we can't exactly know where the wave packets are (the cat in the region in space) that we can't know if it's there and if we open the box we change the circumstances of the box and where it sits in its region in space? or am I totally off based?

Edited February 19, 2014 by PsychedelicPony

[GenderIsAnIllusion 2,177]

If I square root apple, then add orange, what does Coconut equal?

[Scootalove 10,689]

Wow, you're quick

 

@@Scootalove, can you be more specific? I'm not sure I understand your question correctly. What weight do you mean and what scale? And how is it related to Math?

I mean the weight of two objects on a scale, that's what I was asking.

[SasQ 1,376]

 

 

I mean the weight of two objects on a scale

 

OK, what about them? I still don't see a problem.

Is your question about forces on a lever arm, like this one?

 

 

 

 

If I square root apple, then add orange, what does Coconut equal?

 

A peculiar drink

 

Seriously though, numbers are useless without units. You can think of apples and oranges as different units which numbers can operate on. Let's use A for Apples, and O for Oranges. For example, 2 Apples, or 2A in short, means: "Start with no apples, add one (unit), and another one (another unit)". You repeat adding the unit twice. But oranges are different units. So if you add them up, they just make a bunch, but remain separate. In the same way as 2x + 3y, you have 2A+3O (two apples and three oranges).

 

If you had 4 apples and square root them, this means just to put them into a square shape, which makes two rows of 2 apples in each row, that is, a square with side 2. So the square root of 4 apples would be 2 apples. But if you have just one apple, its square root is still 1. So if you have one apple, and you add one orange, you get 1A+1O as a result. Apples and oranges doesn't mix if you consider them to be different units.

 

Now if you try to equate them with coconut (let's use C for Coconuts), you have a third distinct unit: 1A + 1O = 1C. If you have equation like that, then the same terms of its left hand side should be equal to the according terms on the right hand side. Think of it as a balance scale: left hand side of the equation is the left hand scale, and the right hand side of the equation is the right hand scale of the balance. And whatever you do with them, they have to remain in equilibrium. For example, if you had an equation like this: xC + 3C = 5C (unknown number of coconuts closed in a box and three more coconuts equals five coconuts), you can tell right away that there shall be 2 coconuts hidden in the x box. In the same way, if you had an equation like this: xC + 3O = 2C + yO (a box of x coconuts and three oranges on one side, equals 2 coconuts and y oranges in another box), then you can compare them term by term: oranges with oranges, coconuts with coconuts, and tell right away that there should be 2 coconuts in the x box, too, because they have to balance 2 coconuts on the right hand side. And there should be 3 oranges in the y box to balance the other 3 oranges from the left hand side.

 

In this case, your equation doesn't make sense, because it means: root(1A) + 1O = 1C, or after simplification: 1A + 1O = 1C. You have one coconut on the right, but no coconuts on the left. This would mean 0C = 1C, which is false.

 

Unless you're interested in comparing their weights instead, no matter what fruits they are. But then you don't treat them as distinct units of different fruits. Instead of counting fruits, you count kilograms, for example. Counting fruits won't do, because every fruit will have different weight. You can treat those fruits as weights, if you know how much does any of them weight separately. For example, if one coconut weighs 0.5 kg, and you have just that coconut on one scale, balanced with one apple and one orange on the other scale, then you know that one apple and one orange together weigh 0.5 kg in total. Or, if you know that one apple weighs 0.3 kg and one orange weighs 0.2 kg, then the equation 1A + 1O = 1C has to be substituted as 0.3 kg + 0.2 kg = x kg, which tells you that one coconut weighs 0.5 kg.

 

Does that answer your question?

 

 

 

Follow up question

 

Well, no one seems to answer questions except me, so let's do that...

 

 

 

How does Schrodinger's Box fit in to all that. That we can't know if there is a cat in there or not and to open the box would ruin the data. Is this because of the fact we can't exactly know where the wave packets are (the cat in the region in space) that we can't know if it's there and if we open the box we change the circumstances of the box and where it sits in its region in space? or am I totally off based?

 

There's an article on my website which explains exactly that (see under "Schrödinger's feline friend" heading). Take a look at it, and if you had any follow-up questions, feel free to ask.

 

As a bonus, there's an explanation of quantum entanglement with simple, human-scale objects, which shows, how much scientists are mistaken in their descriptions of this phenomenon.

 

I plan to write a follow up to that article soon, about quantum clairvoyance and entanglement through time because I invented some experiments that everyone can do himself with human-scale objects (playing cards) to recreate the "miracles" scientists do with atomic particles in their labs, and convince himself that there's nothing mysterious in it. Just wrong understanding of the phenomenon.

[Scootalove 10,689]

OK, what about them? I still don't see a problem.

Is your question about forces on a lever arm, like this one?

 

 

 

 

 

 

 

Yeah, that's what my question is asking. Sorry if I didn't explain it very well.

[Kel_Grym 1,917]

To be perfectly blunt I believe the universe is governed by newtonian physics (at least above the quantum level), and every phenomena, including even free-will, has a physical explanation.

 

I understand that there is a huge division however, between objective reality and subjective reality, and even though I believe that every subjective sensation including sensory experience, thoughts, and emotions are determined by the brain and that those experiences are merely an effect...I cannot wrap my mind around what that effect is.

 

Qualia. What the heck is it? I know what it is on a philisophical level, but what IS it? You can't scoop the qualia out of my grey matter and touch it. Can it be defined as metaphysical? Or since it's determined by the brain, would it be more proper to call it sub-physical? I don't think there is a connection between the phenomena of qualia and quantum physics. But what do I know?

 

Does qualia occupy a space? Is it non-local? How does my qualitative experience "tune-in" as it were to specifically me? Why not someone else? If everything I sense, think, and feel is an effect of this brain, and I identify with this "effect" specifically, what is the mechanism for it?

 

If all qualia is non-local, what keeps all the collective qualia in the universe seperate from each other? Is it generated or is it some kind of field that the brain simply expresses itself in?

 

Is it even physicaly possible for us to really know this? It's like trying to figure out the velocity and position of a photon at the same time. I can percieve the world, yet for all my efforts, I cannot percieve my perception...

[Brony Number 42 10,069]

 

 

When Townes proclaimed that he invented laser, Bohr came to him particularly to tell him he's wrong, and his laser cannot work, because it breaks the Uncertainty Principle

 

The laser still has to satisfy the uncertainty principle. Like you were saying, a wave packet of some well defined frequency spectrcum will have a broad spectrum of wave numbers. Quantum was not my field of expertise and it has been years since I've studied it. Spectral decomposition fascinates me.

 

Good explanations, although it would take longer to explain why QM isn't so mysterious. Popular media likes to make it out to be some magical thing.

[Frith is Magick 1,471]

 

 

...Quantum Physics...

I had a slight nerdgasm reading that.

 

It has been established that matter is made of waves, and that everything has a wavelenth. I remember back in physics calculating the slit size in a diffraction grating needed to diffract a human. My question combines physics and neuroscience: what would the diffraction of a complex object look like? If an animal was to somehow be diffracted, how would things like thoughts and personalities work between the original and the diffracted versions?  

[Lightwing 12,970]

Here's a tricky one...

 

Is black a color...Or the lack of color?

[SasQ 1,376]

Here's a tricky one... Is black a color...Or the lack of color?

There are no colors in the physical world. Color is what our brains perceive when certain wavelengths of light strike the light-sensitive receptors of the retina inside our eyes. Our brains can even perceive colors which don't exist in the real world ? violet and pink are examples of that.

 

There are different kinds of light-sensitive cells, each of them is tuned to a different wavelength of light, like a little radio antenna. But sending all those signals to the brain would require way more "wires" going from the eye to the brain, so nature invented a neat "compression method" to make the optical nerve cord thinner: it equipped us with additional neurons (nerve cells) inside the retina which first compare the signals from their surrounding photocells and then encode them as just three separate signals which it has chosen for the "primary colors".

 

As I wrote in my Color conspiracy article, that could be any three independent wavelengths (colors) ? that is, none of them could be made of composing the other two ? but Nature has chosen "red", "green" and "blue" for our eyes, because of the special properties of these wavelengths of light: "red" and "blue" wavelengths lay roughly at the edges of the range our eyes can perceive, and they are an octave apart ? that is, the wavelength for "red" is twice as long as the wavelength for "blue". And the wavelength of "green" lays in the middle of these two.

(There's another interesting question about why are these wavelengths at the edges of the visible range, but I'll save it for another time.)

 

So when a particular wavelength of light gets into your eye, and it strikes the photocells, these neurons are trying to figure out what wavelength it is, by comparing how much it resonates with different photocells, and how much it is similar to these three "primary" wavelengths: How much "red" is in it? And how much "green"? And how much "blue"? If the wavelength is exactly one of these three, then there's no problem: just send "100% red" signal to the brain, for example. But when the wavelength is somewhere in-between, the nerve cells in the retina cannot decide, and they send a signal to the brain: "Well, this seems 50% red and 50% green", and then your brain perceives it as "yellow". If it were "75% red, 50% green", then it would be perceived as "orange".

 

Notice that your retina can be easily fooled, because ? for the reason of using this "compression" trick ? it cannot tell whether it actually is being stroke by one single wave with a wavelength in between "red" and "green", or by two different waves with these exact wavelengths of "red" and "green". They will induce exactly the same reaction in these photocells. Stop for a while and think about this profound observation! Two different wavelengths can produce the same effect as one wavelength in between of these two. This fact alone means that you cannot map wavelengths of light to colors in a 1:1 way! Each wavelength of light would have some "color" associated in your brain, but this same "color" perception can be reproduced from many different combinations of wavelengths.

 

Our brains can even produce perception of colors which don't have any corresponding single wavelengths in real world. This interesting phenomenon happens when the photo cells are being stroke by a mix of "red" wavelength and "blue" wavelength, and the neurons in the retina cannot decide if this wavelength is "red" or "blue". They just send a signal to the brain: "Well, this seems half-blue, half-red." And then your brain, forced to map this combination of signals into some perception of color, perceives it as "violet" or "pink" (depending of how much of the "red" and "blue" components are there in the signal). But there is no single wavelength for "violet" or "pink" in the real world. Your brain is just fooling you

 

Now to the black & white:

 

When your photocells are being stroke by all the three "primary" wavelengths for "red", "green" and "blue", or any other combination of three independent wavelengths (e.g. "cyan", "magenta" and "yellow"), or even just by two colors which are "complement" to each other (e.g. "blue" and "yellow"), then the neurons in your retina cannot decide which of these three "primary" signals is stronger, and just send an information to the brain: "Well, this is 33% red, 33% green, 33% blue". And then your brain perceives it as pure white light.

 

Notice, however, that you don't have to use these three particular "primary" colors to see white, nor even use as many as three colors at all! Just two are enough, as long as they are "complementary colors" ? that is, those which lay opposite to each other on the color wheel.

 

Why is that? What makes them "complementary" to our brains?

Well, notice that when the "yellow" wavelength strikes your photocells, these neurons cannot decide for sure if this wavelength is "red" or "green", and they say something like "Well, this is 50% red and 50% green", and your brain would perceive it as "yellow". But there's also that other wavelength which resonates mostly with the photocells for "blue". So the neurons say: "Oh, now this seems rather like 33% red, 33% green, aaaand 33% blue", so your brain understands this signal again as white.

 

This is also a profound observation, because it means that your eyes cannot tell how many wavelengths have been mixed in there when you see something as "white": There could be just two wavelengths (for "complementary colors"), or three wavelengths (for "primary colors"), or millions of wavelengths, or a continuous spectrum ("full rainbow") as it is in the light coming from stars like our Sun.

 

(BTW notice how many images are there in the Internet which include violet or even pink into the visible spectrum of light. This shows how strong is the illusion of our brains about the existence of these particular "colors".)

 

Why is this important?

Because nowadays the corporations and governments force people to use so called "energy-saving light bulbs" (which aren't even light bulbs anymore, but glow lamps, which use plasma glow instead of incandescence). Sure, they save energy, but there's a cost of it popping out in another place: they fool your eyes that you see white by mixing only several wavelengths of light. Here's a photo I made using a spectroscope I constructed myself from a piece of cardboard and a broken DVD:

 

 

As you can see, there are only several wavelengths present (characteristic to the chemical element called Mercury, which is poisonous, BTW) instead of the full rainbow of wavelengths one can find in true white light coming from the Sun. Do you really believe that such a poor spectrum is as good for your body as the rich spectrum from the Sun or an incandescent light bulb? Well, tell it to your skin cells, which require particular wavelengths of light to produce certain vitamins and coenzymes (such as Q10). If your skin doesn't look good, think about what kinds of light you "feed" it. I prefer sunbathing my body as much as I can, feeding it with rich spectrum of the full rainbow of light in perfect Harmony instead of some cheap imitations of Harmony the corporations are trying to force upon me. I advice you the same.

Mane Six approves it too

 

OK, so now when you know everything about color perception, I can answer your question about black:

 

Suppose you mix the wavelengths in a way that neurons in your retina cannot decide any of the "primary colors", so they say "33% red, 33% green, 33% blue", and your brain perceives it as "white". But if the light is dimmer, these three equal signals for "red", "green" and "blue" would be weaker too. Let's say "10% red, 10% green, 10% blue", which is 30% in total, so this light will appear also as a shade of "white" for your brain, but only 30% of the brightest white, that is, "dark gray". If there's no light at all, the signal will be "0% red, 0% green, 0% blue", and this is what your brain would perceive as "black".

 

Your brain always perceives something. It always perceives some "color", even if this perception means "black". So one can say that "black" is a color ? colors are just perceptions of your brain, and this is some perception in your brain after all.

 

But this perception corresponds to no light coming from some particular direction into your eyes. If you see some object as "black", this means that this object does not send or reflect any light into your eyes. Can we say that this object has a color "black"? Not quite, because ? as you hopefully understand now ? color is not a property of the object itself (the pigment is); it's something which is being made up in your brain.

Can we say that this object is being seen as black? Yes.

Can we say that this object doesn't send any light? Yes.

Can we see that it has a pigment which absorbs all wavelengths of light and doesn't reflect any? Yes.

Can we say that it has a "black" color? No.

 

"But wait! I know that apples are red. Why can't I say that they have the red color?"

Because, again, this is not a property of the apples. It depends on the light reflected from them, but it can be altered by changing the lighting conditions. I can use a lamp which doesn't send these particular wavelengths which apples usually reflect, and then they would reflect nothing, so you will see black apples. But are they really "black"? They're neither "black" nor "red". They just usually reflect the wavelength we perceive as "red", and when they have nothing to reflect, they will appear "black" to us. At night everything appears "black", no matter their pigments.

Bananas reflect wavelengths which we perceive as "yellow". It can be pure "yellow" wavelength, or a mix of "green" and "red" wavelengths as well, and you can't tell which one is it. If I shine them with a lamp which sends only "green" wavelength of light, then you will see "green" bananas.

 

That's why physicists need to be careful when speaking of "colors". We need to distinguish what is "real" (wavelengths of light) from what is only a perception of our senses (colors), a creation of our brain in response to these wavelengths.

 

I hope this answers your question. But if you have some follow-up questions, please feel free to ask.

 

The laser still has to satisfy the uncertainty principle. Like you were saying, a wave packet of some well defined frequency spectrum will have a broad spectrum of wave numbers.

Sure. But recall that lasers are special: they produce light waves which are monochromatic, that is, all waves in the laser light have only one wavelength, all the same. They're also 100% coherent, that is, all these waves travel in the same exact direction, they don't diverge. A perfect plane wave, with a focus point at infinity. These two properties make them appear as if they were pure sinusoids.

 

As I said earlier, pure sinusoid of only one wavelength = only one momentum (since momentum is inversely proportional to the wavelength, or directly proportional to the "spatial frequency" as I call it). This means that we can know its momentum with 100% certainty. We still cannot know precise point-wise position along the laser beam, but we can at least narrow it to a line in one precise direction.

 

Sure, lasers obey the Uncertainty Principle in a way, but they also show us a way around it. They are perfect examples of why the Uncertainty Principle is misunderstood by modern physicists: it doesn't say that the world is random and we cannot measure it as precisely as we please. It only says that there are certain measurements which are inter-dependent, that is, they are parts of the same information, because of the wave nature of matter and light.

 

Notice that when you make two laser beams interfere, you will get a precise distribution of wave nodes and precise distribution of interference fringes. Doesn't seem much "random" or "unpredictable" or "fuzzy" to me at all.

 

Same goes with atomic orbitals of electrons in chemical molecules: they form precise standing wave formations, with precise geometrical distribution of wave nodes, which in turn make the precise geometrical forms of crystals possible. When you look at a crystal, you actually see a human-scale replica of the geometry of wave nodes between particular atoms in the molecular grid. This microscopic geometry, when repeated billions of times, is reflected in human scale in the shape of the whole crystal. If quantum world were as fuzzy and random as scientists are trying to convince us it is, crystals wouldn't possibly exist.

Edited April 8, 2014 by SasQ

[Brony Number 42 10,069]

 

 

laser light have only one wavelength, all the same

 A laser is produced when a lot of electrons transistion from one energy level to another. Isn't there an uncertainly in the energy levels of the two states that produces the photon? Maybe I should say "distribution of energy" instead of uncertainty. So that the energy of the photon comes from a distribution, rather than a delta spike. The distribution will be narrow, but finite. Thus when you plot the frequency spectrum you don't have a delta spike, but a narrow distribution. And isn't it true that the laser is not coherent all the time? The frequency will be the same, but the phase can suddenly change. So if you were watching the phase of the wave, it would suddenly change randomly. Are these two phenomena true, and/or related to the undertainly preinciple?

 

I worked with a heterodyne interferometer but that was 5 years ago, and I'm not a laser expert. As I recall, the phase of the laser would not stay constant. That is why we split the beam in two and did a relative phase measurement. Another reason to do that is we didn't have eletronics that could detect a MHz singal, but we measured a kHz beat signal.

[SasQ 1,376]

A laser is produced when a lot of electrons transistion from one energy level to another.

Quite. When you heat something up, or pass an electric current through it, or excite it in some way, there also will be lot of electrons transitioning between energy levels, emitting light. But the problem is that they will do it in an unordered (incoherent) way: at different moments of time, in different directions, and with different phases.

 

Laser action is a special case of emission where atoms emit light in sync with each other. They all do it in the exact same direction (coherence in space, thanks to which the laser beam doesn't diverge with distance), at the exact time when the other wave of light passes them by (coherence in time and phase), and they emit light of the same exact wavelength (monochromatic).

 

Coherence of collective systems is what allows to observe quantum phenomena at human scale, so it's benefiting to study them. Other examples are superconductors (where electronic waves travel in loops unisono), and superfluids (like liquid helium, where a whole liquid behaves like a single atom).

 

Isn't there an uncertainly in the energy levels of the two states that produces the photon?

Not that I know of. I see you have a PhD in physics, so I suppose you know very well that atoms can emit/absorb light only of exact wavelengths (which is responsible for the line spectra). So one just needs to choose the excitation energies so that there were only two energy levels reachable for these atoms, and one transition between them. Atoms won't use other energy levels unless they absorb a proper portion (quantum) of energy (frequency) to switch into it. If no light of that particular frequency is available, they cannot switch to that energy state.

 

There's also a little known detail that not all transitions can produce emission of light. For example, transitions between "s" (spherical) orbitals won't produce light, because the orbital would oscillate in an in-out fashion, like a pulsating air bubble. (This would rather produce longitudinal EM waves which are not well known to most physicists from what I observe.) On the other hand, the transition between "p" orbitals and "s" orbitals, or between two "p" orbitals (dumbbells), would produce oscillation of charge in one particular direction, that is, a dipole moment, which works like a little radio antenna: it would emit light polarized in that direction. One can even produce quadrupole emitters by transitions between two "p" orbitals with different "angular momentum" orientation (e.g. "px" and "py").

 

As you can see, lasers can be explained classically with waves, because atoms are just light-emitting antennae/resonators. You just need to see them as waves, not "probability distributions" (which lack the phase information, which is the key if you want to relate them to electric charges and fields). There are no "quantum jumps" ─ these transitions need some time to occur, they're gradual, not abrupt or instant.

 

So that the energy of the photon comes from a distribution, rather than a delta spike.

Laser spectrum should be exactly the delta spike, since it is monochromatic. When you pass it through a glass prism or a diffraction grating, it will bend, but not spread into component "colors", because it doesn't have any. It's a single sine wave, with a single wavelength (not counting the moments when you turn the laser on/off).

 

Unless you create a laser which uses different transitions at the same time. Then it perhaps could have some components, but still these will be spikes on the spectrum, not a continuous distribution (Gaussian curve).

 

It is quite funny that scientists forget about the continuous spectrum and speak about quantized spectrum when talking about atomic emission/absorbtion of light. Well, it's quantum physics after all, it should be about quanta and quantization, right? But then what about the continuous spectrum from the stars they compare their line spectra with?

 

But on the other hand they forget about quantized spectra when they speak about Heisenberg's Uncertainty Principle, and look for Gaussians everywhere instead of spikes of color

 

The distribution will be narrow, but finite.

Welp, then we would have to dump the quantum theory of energy levels, orbitals and line spectra to the trash can, I guess. Since the theory says about exact wavelengths and wave nodes in quantized conditions.

 

And isn't it true that the laser is not coherent all the time? The frequency will be the same, but the phase can suddenly change. So if you were watching the phase of the wave, it would suddenly change randomly.

I didn't know of such phenomena, so if you know something more, please elaborate. I'm always open to learn something new. And I don't have enough equipment yet to test it myself (which otherwise I'd do with pleasure).

 

Are these two phenomena true, and/or related to the undertainly preinciple?

Don't know about Uncertainty, but I think that such phase shifts wouldn't do much harm, since absolute phase is not an observable in Quantum Theory as far as I know. One can only observe relative phase. (Though perhaps someday someone will figure out how to measure it, so I wouldn't bet on that.) So the phase shifts could be observable perhaps, and they could appear on the spectrum as short-lasting additional spikes or spreads, but I don't know how this could ruin anything or allow measuring something which couldn't be considered measurable already.

 

I worked with a heterodyne interferometer but that was 5 years ago, and I'm not a laser expert.

Interesting nevertheless. If you have some interesting observations/conclusions to share, feel free to contact me on priv or something.

 

As I recall, the phase of the laser would not stay constant. That is why we split the beam in two and did a relative phase measurement.

Yes, this is a good way to make sure both beams be always in phase.

Edited April 8, 2014 by SasQ

[Brony Number 42 10,069]

...

Quantum and lasers were not my field. And I don't do physics any more. But I thought I remembered something about enegy levels being blurred due to quantum effects. I'm too busy not caring about physics to care.I did not pursue it as a career after graduation. But I do want to learn more as a hobby.

[M'aiq the Liar 5,804]

Why are elections in all places at once until viewed? 

[Dattebayo 2,850]

Double D, from "Ed, Edd, and Eddy"...

Is he bald, or...?

[Brony Number 42 10,069]

Double D, from "Ed, Edd, and Eddy"...

Is he bald, or...?

There was an episode where Ed and Eddy saw him with his hat off, but the audience didn't see it. The other 2 were horrified. Edd told them to never tell anyone. I bet he has a condition that makes him bald and gives him a deformed his head.

[Dattebayo 2,850]

There was an episode where Ed and Eddy saw him with his hat off, but the audience didn't see it. The other 2 were horrified. Edd told them to never tell anyone. I bet he has a condition that makes him bald and gives him a deformed his head.

I saw that, I just wanted to know if anyone ever saw what's underneath it...\

 

Do you think he has a dead congenital twin attached to his head...?

[GenderIsAnIllusion 2,177]

OK, what about them? I still don't see a problem.

Is your question about forces on a lever arm, like this one?

 

 

 

 

A peculiar drink

 

Seriously though, numbers are useless without units. You can think of apples and oranges as different units which numbers can operate on. Let's use A for Apples, and O for Oranges. For example, 2 Apples, or 2A in short, means: "Start with no apples, add one (unit), and another one (another unit)". You repeat adding the unit twice. But oranges are different units. So if you add them up, they just make a bunch, but remain separate. In the same way as 2x + 3y, you have 2A+3O (two apples and three oranges).

 

If you had 4 apples and square root them, this means just to put them into a square shape, which makes two rows of 2 apples in each row, that is, a square with side 2. So the square root of 4 apples would be 2 apples. But if you have just one apple, its square root is still 1. So if you have one apple, and you add one orange, you get 1A+1O as a result. Apples and oranges doesn't mix if you consider them to be different units.

 

Now if you try to equate them with coconut (let's use C for Coconuts), you have a third distinct unit: 1A + 1O = 1C. If you have equation like that, then the same terms of its left hand side should be equal to the according terms on the right hand side. Think of it as a balance scale: left hand side of the equation is the left hand scale, and the right hand side of the equation is the right hand scale of the balance. And whatever you do with them, they have to remain in equilibrium. For example, if you had an equation like this: xC + 3C = 5C (unknown number of coconuts closed in a box and three more coconuts equals five coconuts), you can tell right away that there shall be 2 coconuts hidden in the x box. In the same way, if you had an equation like this: xC + 3O = 2C + yO (a box of x coconuts and three oranges on one side, equals 2 coconuts and y oranges in another box), then you can compare them term by term: oranges with oranges, coconuts with coconuts, and tell right away that there should be 2 coconuts in the x box, too, because they have to balance 2 coconuts on the right hand side. And there should be 3 oranges in the y box to balance the other 3 oranges from the left hand side.

 

In this case, your equation doesn't make sense, because it means: root(1A) + 1O = 1C, or after simplification: 1A + 1O = 1C. You have one coconut on the right, but no coconuts on the left. This would mean 0C = 1C, which is false.

 

Unless you're interested in comparing their weights instead, no matter what fruits they are. But then you don't treat them as distinct units of different fruits. Instead of counting fruits, you count kilograms, for example. Counting fruits won't do, because every fruit will have different weight. You can treat those fruits as weights, if you know how much does any of them weight separately. For example, if one coconut weighs 0.5 kg, and you have just that coconut on one scale, balanced with one apple and one orange on the other scale, then you know that one apple and one orange together weigh 0.5 kg in total. Or, if you know that one apple weighs 0.3 kg and one orange weighs 0.2 kg, then the equation 1A + 1O = 1C has to be substituted as 0.3 kg + 0.2 kg = x kg, which tells you that one coconut weighs 0.5 kg.

 

Does that answer your question?

 

 

 

Well, no one seems to answer questions except me, so let's do that...

 

 

 

There's an article on my website which explains exactly that (see under "Schrödinger's feline friend" heading). Take a look at it, and if you had any follow-up questions, feel free to ask.

 

As a bonus, there's an explanation of quantum entanglement with simple, human-scale objects, which shows, how much scientists are mistaken in their descriptions of this phenomenon.

 

I plan to write a follow up to that article soon, about quantum clairvoyance and entanglement through time because I invented some experiments that everyone can do himself with human-scale objects (playing cards) to recreate the "miracles" scientists do with atomic particles in their labs, and convince himself that there's nothing mysterious in it. Just wrong understanding of the phenomenon.

Consider my mind blown...... O yeah

[SCS 7,537]

Hey @SasQ, I'm not sure if you're still answering questions here, but if you are I have a bunch for if/when you have time. I've been reading through a bunch of your symbolism posts and you seem to be incredibly knowledgeable about a lot of my primary interests. 
 
I may jump around a bit in regard to subject matter in my questions. 
 

---

• One of my main passions in life is mathematics. However, one thing that frustrates me is that I do not have a good understanding of what things actually mean in mathematics, what their foundations are, where they come from, how they work at a deeper level, and so on. I'm currently in 11th grade, and I'm wrapping up my studies in the courses AP Calculus AB and AP Statistics. Both are designed to mirror college level courses, the former designed to mirror an introductory course regarding the calculus of single-variable functions in college, and the latter designed to mirror an introductory course regarding algebra-based probability and statistics. For Calculus, one thing that I both take pride and concern in is that one of my strongest skills is in the area of finding derivatives and antiderivatives. I am often able to flow through such problems with ease, even trickier derivatives requiring use of the Chain Rule or antiderivatives requiring u-substitution. What concerns me about this is that this does not require me to think much at all. It has become an automatic process. What I wish to understand but currently do not is what all of this stuff means, and where it came from. Why does u-substitution work? How would one derive its most fundamental proof? Why is the derivative of the natural logarithm function equal to the reciprocal function? Why is the derivative of sine cosine? My teacher does teach us the meaning behind things, but I just feel like I'm not getting it. Memorizing mathematical rules and techniques has its place, but that will only get me so far. If I want to truly study life with math (which I do), I need to be able to figure out what it all means. So, I'm not asking you to explain all of math to me, though providing some example explanations would be great, but most of all I would love to learn how to think about math at a deeper conceptual level, how to understand what everything means beyond the basic computations.
  
   
• How do you think about the world at a deeper conceptual level in regard to physics? I want to be a physicist, yet I am coming to realize that I have yet to be able to develop the ability to truly think about and understand physical phenomena in my mind. The only real physics course I have taken thus far was Advanced Physics in 10th grade. I plan to take AP Physics I next year. In all honesty, I understood virtually nothing in the physics course I took last year. This was in part due to my poor academic habits back then that I have been overcoming this year, but I feel like I'm just not used to thinking about the world in the way necessary to understand physics, and I wish to develop that ability. Another issue is that I found the class to be boring, so I lost motivation to try to understand. My main interests lie in theoretical physics, quantum mechanics, and astronomy/astrophysics. These are the specific areas of physics that I wish to pursue professionally. But the thing is, I need to understand the basics before I could hope to understand what I want to be able to do research in some day. It's not that I doubt my ability to do this: I think I do have the ability. I'm just not sure how to expand it and develop it. I'm used to thinking about the world on a spiritual and philosophical level. I have done that so much that I have developed a strong ability to do so. Thinking about the world that way just feels natural to me. It's not something I learned. It's something I just do. However, I am also interested in studying life physically, and I'm not quite sure what the proper mindset is to approach such problems. So, I'm not so much asking you to explain physics to me, but it would be great if you could give me advice in regard as to how one can think about physics at a deeper level.
  
   
• Unless I am mistaken, you are a lucid dreamer. How did you develop that ability? I have a strong interest in doing so, but in all honesty I struggle with maintaining enough focus on that endeavor along with all other sorts of things I encounter and think about in daily life. I have had a few lucid dreams more recently: they seemed to occur simply as a result of being interested in, thinking about and reading about the idea. What sort of things have you successfully used lucid dreaming for? Does it help you in spiritual endeavors (if you have any, I'm not sure whether or not you have any spiritual beliefs)? Does it help you with mathematics or physics at all? I plan to attempt to push lucid dreaming to the absolute limits (if there are absolute limits), to see what is possible.
  
   
• I will likely begin to encounter multivariable calculus later next year. I am taking AP Calculus BC next year. The official BC curriculum is designed to mirror a second semester course in the calculus of single-variable functions that introduces more advanced integration techniques, infinite series, the calculus of polar curves and parametric functions, as well as an introduction to the basics of vector calculus. However, if I get the same teacher next year that I got this year (and I hope I will, he is a wonderful teacher) from what I have heard he will likely finish the entirety of the actual BC curriculum by February, and then introduce us to multivariable calculus even though it's not on the BC test at all. So, I would like to be as prepared as possible to encounter that next level of calculus. If you could give me a summary and explanation of its main processes and ideas, how it relates to single-variable calculus, and what it all means at a deeper level, that would be awesome.
  
   
• What are your thoughts on out of body experiences, near death experiences, and their potential relation to dreams? I'm not entirely sure what I think about that yet. I have had experience with both OBEs and lucid dreaming. They felt like two distinctly separate categories of experience, but I do not have anywhere near enough experience with either yet to determine the validity of that impression. For example, it is possible that they only felt different because I expected them to be different.
  
   
• I hope to become a physicist when I am an adult. My main areas of interest in physics would be theoretical physics, quantum mechanics, and astronomy/astrophysics. I'm not sure whether or not my current educational plans are good. At the very least, I plan to do a double major in mathematics and physics as an undergraduate. The major in mathematics would be not only to strengthen my mathematical foundation to help me succeed in the theoretical areas of physics, but because I love mathematics and have a tremendous interest in it. I am also very interested in philosophy. I am strongly considering going for a triple major in mathematics, physics, and philosophy, but I just don't know if that would be reasonable in terms of the amount of work required to do something like that. However, I feel like doing all three would best prepare me for what I want to do, which is to figure out mysteries of life. The college I plan to go to also has a program in which you can earn both a bachelor's degree and a master's degree in mathematics in only five years, and I plan to do that. After I complete all of my undergraduate studies, I would go on to a graduate program to earn a PhD in physics. After that, I would try to find research positions relevant to my primary interests in the field. However, I don't want to just be a physicist. I want to be a mathematician and a philosopher as well. I want to discover the world using not only physics, but mathematics, philosophy, and spirituality as well. I do not want to take a solely left-brained approach to life, neither do I want to take a solely right-brained approach to life. I feel that doing both would enable me to understand life at a much deeper level. So, do you think my educational plans would provide me with the knowledge and skills necessary to accomplish something like this? Or, is the formal educational system a waste of time? Would I be better off learning on my own through books and the internet? Or, would a combination of both going through the formal education system and doing learning on my own be the most ideal?
  
   
• I have a lot of interest in ancient knowledge: sacred geometry, spirituality, occultism (not of the dark variety), and so on. Many people label this as "mumbo jumbo" nowadays, but I think doing that is unwise. I don't know whether or not ancient knowledge is correct, but if people accepted it as wisdom they did so for a reason. Even if that reason were incorrect, it would be worthwhile to know about it and think about it. Besides, when attempting to figure out life and the world, it would be pretty silly to disregard thousands of years of thought that came before my own. Now, the problem is is that my knowledge in these areas is very minimal, and I'm not sure where to start in regard to learning more. Where, and how, would you recommend that I start learning more about these things?

These are the main questions I wish to ask you for now. I may have more to ask you at a later time, if you wouldn't mind.

[Shady Bubbles 429]

You all forgot the most important question of all!

 

Will it blend?

 

 

 

But no seriously, if a tree falls in a forest and no one is around, does it make a sound? This can't be that hard to test, all you'd need is a simple audio recorder. Set up a tree to fall at the push of a button (say a mechanism that will saw the tree down or something) and drive far far away. Push the button, then go back and retrieve the tape. How have we not tested this already?