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posted on Mar, 15 2015 @ 12:31 PM

originally posted by: LibertyKrueger

originally posted by: dragonridr

originally posted by: Bedlam

originally posted by: mbkennel

If you sort of know where it is, then it's going to be moving around even at T=0.

So...can it emit phonons even in ground state/T=0?

A ground state is merely the lowest energy level an atom can have. Doesn't mean there is no energy. with an atom say we have an electron we add to much energy it flies off. This is what we call ionization. Now electron does not have to be in a particular place or energy level.An electron state is a superposition of states of definite energy level (energy eigenstates).Now even in a ground state an atom has potential energy. Let's say I set a glass of water in a cup and place it on the table. That water will sit there forever until something perturbed it such as us shaking the glass. Now the water is no longer in its lowest energy state.

Now atoms are the same way if nothing perturbs the electron in to excited energy eigenstate, then it simply will never decay it sits there becausr energy eigenstates are stationary; they do not evolve into anything other than themselves.But here's the catch being completely without external perturbation is actually impossible. The uncertainty principle provides the electromagnetic field with vacuum fluctuations. Meaning even our electron in our atom is constantly being shaken up even in its lowest energy state.

Actually, I think it's the other way around. That the vacuum fluctuations of the EM field are driven by the motions of matter rather than those fluctuations being primarily responsible for matters motions. The reason that I think that matters motions are primarily internally driven is because of the reported increase of internal frequency as the temperature of matter approaches absolute zero. As the outer structure of matter is being prevented from moving, it provides a more solid surface against which the internal deflections of the masses momentum take place. This increases the effective rebound energy of that internal deflection thereby increasing the frequency of those motions by eliminating the deflective losses that moving the external particle structure would impart.

You misunderstand me vacuum fluctuations don't give the atom energy it disturbs it. meaning an atom never truly reaches it's lowest energy state possible. Back to my glass of water the water inside will sit still without outside interaction. Now I vitae the table it will find its lowest energy state basically create currents in our glass. That is now it's lowest energy level possible.

Well even an atom in its ground state has a constant outside force and that is vacuum energy. As for the other part are you saying frequency increases the colder the atom have to explain what you mean.

posted on Mar, 15 2015 @ 12:58 PM

originally posted by: LibertyKrueger
The reason for the question is due to an anomaly I came across in some published works that seem to indicate that the vibrational frequencies of matter are slowing very slightly over time. If that's the case, then it might need to be accounted for by changing or revising our assumptions about what is driving those motions.
It would help if you cited the research you're talking about, but since you didn't, let me take a guess and you can cite other research if this isn't what you're talking about.

The vibration of matter in the universe is slowing down slightly over time, and while the cosmic microwave background (CMB) was considered "an anomaly" when first discovered, it's no longer an anomaly but understood to be radiation leftover from the big bang.

The current temperature of the CMB is about 2.72548±0.00057 K which is about 1100 times cooler due to expansion of the universe, than it was when formed. Since the universe is continuing to expand at an accelerated rate, the CMB is predicted to continue to cool accordingly, and vibrations of matter in the universe will be reduced as a result. This is of course a generality, since new stars will continue to form and when they do the vibration/temperature of matter in the newly formed star will increase, so the cooling doesn't apply to all matter. However all the estimates I've seen for the percentage of baryonic matter in stars say the percentage is relatively low.

edit on 15-3-2015 by Arbitrageur because: clarification

posted on Mar, 15 2015 @ 02:03 PM

originally posted by: mbkennel

originally posted by: Bedlam

originally posted by: mbkennel

If you sort of know where it is, then it's going to be moving around even at T=0.

So...can it emit phonons even in ground state/T=0?

No, not propagating ones which carry off energy to infinity. (it is in the ground state after all).

Heh.

posted on Mar, 15 2015 @ 02:37 PM

The state of electromagnetism is a function (quantum mechanical wavefunction) of functions (the E&B fields), which has certain requirements imposed upon it which use Planck's constant such that when you make a modal expansion in some function basis you sum up elementary terms, each one of which, is called a 'photon', and if the photon has a definite frequency it has a proportional energy and momentum and there is a minimum non-zero amplitude.

is it ? Or is it more that the functions are mathematical constructs trying to visualize how it could look like.

Another way to see the EM field and it's E and M interactions is without any chunkiness in it.
Fluid like, where the field is the fluid and the E and B forces are pressure like effects.

Everything is made out of stuff obeying laws of quantum field theory, as far as we can tell. Particles are the 'expansion' of the quantum fields in some useful quantum mechanical bases.

well NO!
The theory of yours is limited to chunkiness, uncertainty and a constant speed C which are
imperative for it to work.
Reality is not obeying any laws of quantum field theory ! Quantum field theory is describing at it's best ques what reality is.

posted on Mar, 15 2015 @ 02:59 PM
Is it physforum relocated?

Dejavu

DO

posted on Mar, 15 2015 @ 03:09 PM

Sure...

Quantum mechanics is also the most precisely tested and most successful theory in the history of science.

But if you think you can do better, go ahead.

posted on Mar, 15 2015 @ 03:21 PM

One question - phase space. I know the definition and have an inkling of it's purpose and use but cannot grasp it's practical usefulness.

posted on Mar, 15 2015 @ 04:36 PM
The pendulum example in the Wikipedia article should be pretty self explanatory. It's an alternate way of looking at the motion of the pendulum. You can calculate the motion of the pendulum without using phase space, so it's not a requirement to use phase space.

Likewise there is an alternate formulation of quantum mechanics using phase space, but similarly I think anything you can do with phase space you can also do without using phase space. Maybe some experts here have used phase space more than I have and can tell you more.

posted on Mar, 15 2015 @ 04:44 PM
Some crackpot decided to take on.

How many dimensions we have out there?

My question.

DO

posted on Mar, 15 2015 @ 04:56 PM

I suppose the answer depends on whether or not you believe string theory, (or M-theory), or should I call it "string hypothesis"? It's never been proven but a popular version says there are 11 dimensions, and there are other hypotheses that have different numbers of dimensions. Space-time has four dimensions that we know of, but I don't think anybody is sure about the extra seven dimensions, or whatever number of extra dimensions is in a particular hypothesis.

posted on Mar, 15 2015 @ 05:01 PM

originally posted by: Arbitrageur

I suppose the answer depends on whether or not you believe string theory, (or M-theory), or should I call it "string hypothesis"? It's never been proven but a popular version says there are 11 dimensions, and there are other hypotheses that have different numbers of dimensions. Space-time has four dimensions that we know of, but I don't think anybody is sure about the extra seven dimensions, or whatever number of extra dimensions is in a particular hypothesis.

Ok. How we can post here our questions when we all know there will be an answer similar to the above?

Thanks anyway, dude.

DO

posted on Mar, 15 2015 @ 05:09 PM
Some questions will have fairly definite answers which have a high probability of being correct based on lots of experimental evidence.

Other questions will be at the limits of our knowledge where nobody has any definite answers. The problem with string theory so far is it hasn't been tested, though some people have ideas on how they might test it. Until those experiments are performed and the answers obtained, I don't see how you can expect any better answer. The thread title is "Ask any question you want about Physics"; it says nothing about guaranteeing there will be an answer.

edit on 15-3-2015 by Arbitrageur because: clarification

posted on Mar, 15 2015 @ 06:20 PM

originally posted by: mbkennel

a) There is an electric field in the direction of oscillation. It's vector direction is static (unchanging with time), so there is no *radiation* in the direction looking straight on the oscillation.

But if the electric field, or vector, is attached the the particle; and the particle is moved, will not the electric field or vector be moved in that direction? I suppose first we must ask, or perhaps this has something to do with the nature of electron spin but; if an electron exists in free space; Can we agree that you as an entity, can approach the electron from 'all surrounding angles'? You can be above the electron, you can be below it, you can be on 360 degrees of its sides, and all possible other angles one can surround a point? From this comprehension, if you were to put the electron into motion in separate trials, from each possible angle of approach, to an ultimate frame of reference, is the ensuing EM radiation, created and propagated exactly the same when the electron is approach and accelerated in separate trials from every possible angle?

Before you accelerate the electron, is there not an electric field in all directions in relation to the electron? Why when you move the electron, the electric fields attached 360 degrees surrounding the electron (and potentially more degrees dimensionally) are not all moved?

b) The dynamics of the electric and magnetic field are not the same as mechanical strings.

The field lines are partial representations of the vector field, which is a vector at every point in space, the same way that contour lines on a geophysical plot are representations of the scalar elevation field. They are graphical shortcuts, not physical objects.

They represent physical objects, if physical object is defined as "that which is not nothing", and then EM radiation is referred to as a physical object.

The state of electromagnetism is a function (quantum mechanical wavefunction) of functions (the E&B fields), which has certain requirements imposed upon it which use Planck's constant such that when you make a modal expansion in some function basis you sum up elementary terms, each one of which, is called a 'photon', and if the photon has a definite frequency it has a proportional energy and momentum and there is a minimum non-zero amplitude.

So in my ball and fishing line example. Or electron in free space. The electron in free space, must be attached to a substance of non nothingness, which when the electron is moved, that substance is moved and is detected as EM radiation. The substance must exist and have a greater than 0 value, prior to the electron being moved. (I just had a thought wondering if its possible, well ive had this thought before, that all of our theories are a bit iffy, regarding these fundamental things like electron existing and relating to EM radiation and field, because we on earth are constantly moving in multiple directions, spinning, revolving, rotating, orbiting, orbiting, traveling linearly, all in relation, and it might be that our comprehension of electron and relation to its light creation is not based off of something fundamental and underlying space, but related to the relative motion of all physical bodies and their complex regular motions in the systems, and the reaction of when quanta, namely for example and electron, is focused in on its relation to altering its position relatively to all other traveling bodies in the system, and the result is energy being freed up from the other bodies, like every time we do an experiment with an electron it is like taking a tire iron while driving 60 mph down a high way, sticking your arm out the window of the moving car and dragging the tire iron on the ground, and sparks are flying out, and so you think that fundamentally, the tire iron representing a fundamental particle, every time you accelerate it sparks fly, though I suppose what is so baffling about the apparent reality and subsequent theory, is that it appears as if the entire universe is full to the brim with pavement, and there are tire irons everywhere, and every a tire iron is accelerated, the pavement which exists every where, starts to propagate a sparking, not in all directions 360 degrees squared or cubed, but none the less)...so the substance that is attached to the electron;

posted on Mar, 15 2015 @ 06:23 PM

originally posted by: mbkennel
The state of electromagnetism is a function (quantum mechanical wavefunction) of functions (the E&B fields), which has certain requirements imposed upon it which use Planck's constant such that when you make a modal expansion in some function basis you sum up elementary terms, each one of which, is called a 'photon', and if the photon has a definite frequency it has a proportional energy and momentum and there is a minimum non-zero amplitude.

(continued)

When you invoke separate conceptual and actual, theoretical and practical field lines, essences and characteristics of substance, electric and magnetic field, how does that transfer over to this substantial view of the substance the electron is attached to; if we can approach the electron from all angles and recieve results equally, isotropically (I am prepared for you to say due to the nature of spin, we cannot, but require you to express the nature of the existence of the substance surrounding the electron, which demands that this cannot be so, or what the meaning of the fundamental characteristic of the electron itself is, that this cannot be so); what is the nature of this substance that it itself has two distinguished characteristics? Or, is electric and magnetic not two different things, but two different results from the same one thing? If I slap you on the cheek it is possible your cheek will hurt, and my hand will hurt, and both of our feelings may be altered, woah, thats 4 different distinct characteristics all from one singular event.

Physics used to be called Natural Philosophy, for good reason. I suggest you study it. The concepts and assertions of truth generally accepted cannot be adequately conveyed by linguistic means alone. The description of the photon above is pretty much jibberish unless you have experience with the mathematics and physics that it refers to.

I wonder if you're lazy.

I am not lazy, I am an all or nothing type of person, and I have dedicated this all or nothing attitude to a few other pursuits. Because I cannot dedicate my self fully to physics, I am not going to attempt to learn everything about physics, thus my interest lies in the most fundamental, which is what I most want to know about anyway, and physics itself has not even successfully comprehended this, and this is all I want to know, so why would I dedicate a massive amount of time and mind memory to beating around the biggest bush, to leave me with the exact same questions I have for the vacancies in modern theory I have now?

posted on Mar, 15 2015 @ 07:09 PM

originally posted by: KrzYma

The state of electromagnetism is a function (quantum mechanical wavefunction) of functions (the E&B fields), which has certain requirements imposed upon it which use Planck's constant such that when you make a modal expansion in some function basis you sum up elementary terms, each one of which, is called a 'photon', and if the photon has a definite frequency it has a proportional energy and momentum and there is a minimum non-zero amplitude.

is it ? Or is it more that the functions are mathematical constructs trying to visualize how it could look like.

Another way to see the EM field and it's E and M interactions is without any chunkiness in it.
Fluid like, where the field is the fluid and the E and B forces are pressure like effects.

That doesn't make sense, and at least regular fluids can't support transverse forces like magnetism. E&B are the fields. The late 19th century was looking for all sorts of mechanical and fluid like models for electromagnetism until Einstein & the Michaelson-Morely experiments. The mechanical properties necessary were so strange and unlikely that it didn't make sense.

Everything is made out of stuff obeying laws of quantum field theory, as far as we can tell. Particles are the 'expansion' of the quantum fields in some useful quantum mechanical bases.

well NO!
The theory of yours is limited to chunkiness, uncertainty and a constant speed C which are
imperative for it to work.
Reality is not obeying any laws of quantum field theory ! Quantum field theory is describing at it's best ques what reality is.

Which is why I said "as far as we can tell".

By the way, the 'quantization' in quantum mechanics is not quite the same thing as simple 'quantization' or 'discretization' as found in electronics.

posted on Mar, 15 2015 @ 07:15 PM

originally posted by: ImaFungi

originally posted by: mbkennel

a) There is an electric field in the direction of oscillation. It's vector direction is static (unchanging with time), so there is no *radiation* in the direction looking straight on the oscillation.

But if the electric field, or vector, is attached the the particle; and the particle is moved, will not the electric field or vector be moved in that direction?

In the direction of motion? No. It's not something mechanical.

I suppose first we must ask, or perhaps this has something to do with the nature of electron spin but; if an electron exists in free space; Can we agree that you as an entity, can approach the electron from 'all surrounding angles'? You can be above the electron, you can be below it, you can be on 360 degrees of its sides, and all possible other angles one can surround a point? From this comprehension, if you were to put the electron into motion in separate trials, from each possible angle of approach, to an ultimate frame of reference, is the ensuing EM radiation, created and propagated exactly the same when the electron is approach and accelerated in separate trials from every possible angle?

No. I showed the formula before. There is an angular dependence based on the motion patterns of the charge and the observation point.

They are not the same as mechanical strings, but there must be some physical substance, and mechanical mechanism, as to how this function of reality occurs. An electron existing in free space, what is it attached too that allows it to propagate EM radiation; is the electric and magnetic field a densely packed medium of photons?

It's the EM field whose fine underlying dynamics is represented as a summation of allowable modes each of which is called a 'photon'.

There must be some substance there, or energy if you want to call it that, some non nothing to be most clear.

Just the fields in all space.

The electron exists, there must exist surrounding it, non electron, but non nothing, which when the electron is shaken, the non nothing the electron is attached to, is also shaken, and this is what is detected as EM radiation. The non nothing that the electron is attached to, that you term the electric and magnetic field line system or field or vector or scaler, must be something that exists. It must at every point in space (potentially, depending on how densely packed it is... of course it most likely is not so densely packed that an volume of few planck lengths of average energy density is isotropic) so like all things, there might be a gradient, a meshing, a webbing, a netting, a fielding. A bath tub of still water for example, would we say there is a non 0 value point every where in the volume? Or would we admit that when we zoom in there is real nothing space in between actual substantial particles of mass and energy, and so it cannot be said every point in the volume is of equal value? Likewise, the electron existing in free space, it is attached to a non nothing substance, which when the electron is moved, it moves, and in this way its movement can be detected and termed EM radiation. Prior to the electron being approached and moved, can the non nothing space surrounding the electron, attached to the electron, that moves when the electron is moving, can that local volume of space (I am not referring to any substance of space, other than the substance medium responsible for being detected as EM radiation), so I shall say can the local volume of substance which is responsible for being detected as EM radiation, be said to have equal value at all planck points prior to the electrons acceleration?

No, the field's strength drops off as 1/R^2. The direction is radial away from the positive charge and in towards a negative charge (this is a convention).

This is what i mean when I ask, what is the average energy density of the undisturbed EM field

In c.g.s units the energy density at any location is (|E|^2 + |B|^2)/8pi with E and B being the vector of the field at that point.

and because you and science doesnt know,

Fortunately we know.

The state of electromagnetism is a function (quantum mechanical wavefunction) of functions (the E&B fields), which has certain requirements imposed upon it which use Planck's constant such that when you make a modal expansion in some function basis you sum up elementary terms, each one of which, is called a 'photon', and if the photon has a definite frequency it has a proportional energy and momentum and there is a minimum non-zero amplitude.

So in my ball and fishing line example. Or electron in free space. The electron in free space, must be attached to a substance of non nothingness, which when the electron is moved, that substance is moved and is detected as EM radiation. The substance must exist and have a greater than 0 value, prior to the electron being moved. (I just had a thought wondering if its possible, well ive had this thought before, that all of our theories are a bit iffy, regarding these fundamental things like electron existing and relating to EM radiation and field, because we on earth are constantly moving in multiple directions, spinning, revolving, rotating, orbiting, orbiting, traveling linearly, all in relation, and it might be that our comprehension of electron and relation to its light creation is not based off of something fundamental and underlying space, but related to the relative motion of all physical bodies and their complex regular motions in the systems, and the reaction of when quanta, namely for example and electron, is focused in on its relation to altering its position relatively to all other traveling bodies in the system, and the result is energy being freed up from the other bodies, like every time we do an experiment with an electron it is like taking a tire iron while driving 60 mph down a high way, sticking your arm out the window of the moving car and dragging the tire iron on the ground, and sparks are flying out, and so you think that fundamentally, the tire iron representing a fundamental particle, every time you accelerate it sparks fly, though I suppose what is so baffling about the apparent reality and subsequent theory, is that it appears as if the entire universe is full to the brim with pavement, and there are tire irons everywhere, and every a tire iron is accelerated, the pavement which exists every where, starts to propagate a sparking, not in all directions 360 degrees squared or cubed, but none the less)...so the substance that is attached to the electron;

Again, all covered in 1st semester electromagnetism.

posted on Mar, 15 2015 @ 07:55 PM

originally posted by: LibertyKrueger
The reason for the question is due to an anomaly I came across in some published works that seem to indicate that the vibrational frequencies of matter are slowing very slightly over time. If that's the case, then it might need to be accounted for by changing or revising our assumptions about what is driving those motions.

originally posted by: Arbitrageur
It would help if you cited the research you're talking about, but since you didn't, let me take a guess and you can cite other research if this isn't what you're talking about.

The evidence for this (although not well known) is very simple. In the 300+ years prior to 1960 there were 164 separate published measurements of the speed of light using 16 different measurement techniques that always showed a slight decrease from formally obtained results. That steady slowing trend stopped suddenly when they started using atomic clocks in the 1960s which indicates that both the measured quantity (speed of light) and the new measuring tool (atomic clocks) are changing at the same rate, so no relative change would be detected between the two. There is other evidence for this as well. Because the former standard for determining the length of a second was based on orbiting bodies before 1967, the gravitational constant should be changing if atomic frequencies are constant. Statistical studies of the gravitational constant haven't shown any such variation. If atomic frequencies are slowing, then the properties of the atom such as Planck's constant et al should also be changing. Statistical studies of past measurements do indeed show these changes and in a direction that is consistent with slowing atomic frequencies. So the speed of light is tied to the vibrational frequencies of matter and both are slowing very slightly.

See M.E.J. Gheury de Bray's work "The Velocity of Light" Science, Vol. 66 Supplement x, Sept 30, 1927, "The Velocity of Light" Nature, p. 464, March 24, 1934, "The Velocity of Light" Nature, p. 522, April 4, 1931, T.C. Van Flandern's work "Is the Gravitational Constant Changing?" The Astrophysical Journal, Vol. 248 pp.813-816, Sept. 1, 1981, "Is the Gravitational Constant Changing?" Precision Measurement and Fundamental Constants II, National Bureau of Standards (U.S.A.) Special Publication 617, pp. 625-627, 1984, and Alan Montgomery and Lambert Dolphin's work "Is the Velocity of Light Constant in Time?" Galilean Electrodynamics, Vol. 4, No. 5, pp. 93-97, Sept/Oct 1993.

posted on Mar, 15 2015 @ 08:50 PM

originally posted by: LibertyKrueger
If atomic frequencies are slowing...

And again, what do you mean by this? Do you mean bond vibratory frequencies, or the frequency of emissions during an electron transition, what? "Frequencies" is one of those words that's not very revelatory.

posted on Mar, 15 2015 @ 09:07 PM
There have been some various competing claims about whether or not there have been variations measured in the fine structure constant, of which the speed of light is a component and such variation would be one way we could tell if the speed of light was actually changing. Whether the claims of variation in fine structure constant are true or not I don't know, but even if they are true, the claimed changes are very small so this puts constraints on how much the speed of light could have changed, as explained here:

Is the speed of light constant?

What would it mean to say that c varied with time? Would it actually mean anything? In conventional units, the metre is defined as the distance that light travels in about 3 nanoseconds. (This is not quite the same thing as saying that the metre is the distance travelled in 1/c seconds.) Suppose that we calibrate marks on a ruler using this definition one year, then next year find that light takes longer than 3 ns to travel the length of the ruler. According to the definition, we wouldn't say that the speed of light had fallen, but that the ruler had lengthened. How could that be? What would that mean?

Now the size of the ruler depends upon the size of atoms, which in turn is related (in our units) to quantum mechanical and electrical quantities. Could the atoms in the ruler have grown because electricity had faded, or because Planck's constant had increased? How would we know which?

Time, space, electricity and quantum mechanics
Our imaginary experiment shows that electrical and quantum effects are inter-related. Charge is carried by electrons and protons, which are subject to (quantum) mechanical laws. It is meaningless to talk of changes in an electromagnetic constant or a quantum mechanical one alone. Asking whether the speed of light changes over time superficially appears to be a reasonable question: it makes grammatical sense. But it doesn't make scientific sense. In science, a proposition must be, in principle, testable. (For instance, if you propose that there is an invisible gorilla in the room, and that she has no mass and no effects that can be detected, then your proposition is not a scientific one.)

The fine structure constant, α
So is there something that physicists can measure for which a change over time would have meaning? Yes, there is. Any quantity that doesn't have units can be measured as a ratio. For example, the fine structure constant α is a measure of the relationship between electromagnetic effects and quantum effects and it has no units.

Because it has no units, we can think of it as a ratio. Here is a simple explanation: In the Bohr-de Broglie-Sommerfeld model of the hydrogen atom, an electron 'orbits'* a proton, 'travelling' in a circle at 'speed' vH. In this picture, the fine structure constant

α = vH/c

and takes a value close to 1/137. (There are few pure numbers in physics, and so the number 137 is especially memorable for physicists.) Let's look at more basic expressions for α later. For now, let's ask:

Has the fine structure constant changed over time?
The obvious answer is "not much, or we should have noticed it". The temperature of stars (including the sun) is a strong function of α, so even a modest change would have been very observable.
So if we aren't seeing much of a change in the temperature of stars over the last 200 years, which is a function of the fine structure constant, and as far as I know, we aren't, then if the speed of light varied at all in the last 200 years, it can't be by very much. What I think are the most plausible ideas for speed of light changing relate to time scales at the birth of the universe, and we will need more measurements to confirm or rule out such claims but to my knowledge the most accurate measurements show the fine structure constant is pretty constant, meaning very tight limits have been placed on how much it could have changed.

However Alan Montgomery and Lambert Dolphin's paper doesn't seem to mention or consider implications for the fine structure constant that I can see, so their treatment of the topic appears to be incomplete, as they don't provide supporting data of stellar temperature changes to support their claim of changes in the speed of light (and thus changes in the fine structure "constant").

posted on Mar, 16 2015 @ 09:14 PM

originally posted by: ImaFungi

No, virtual photon is a term used in Quantum Electrodynamics for interactions. If you read Feynman's QED book it might clear up some of that.
Why do you say science doesn't know the energy of a position, "x" in a quantum field?
Just because there is no eigenstate for x you would still have a superposition of different field values (phi) and it works out like a quantum wave measurement.

It's a quantum object so there is still going to be quantum features, superpositions and energy density probabilities.

As to particles having zero vibration, that is not possible because of the Uncertainty Principle. There is always an amount of position or momentum that cannot be known so a particle with zero movement will never be observed.

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