Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Aquarius on 30/07/2015 17:33:17
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[;)]
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If you view two atoms seperated by space say the hydrogern atom, both with electrons spinning around them in a clockwise direction they will in effect be emitting eltromagnetic waves towards and away from each other.
That's incorrect. In fact it was for reasons exactly like this that gave birth to quantum mechanics (QM). Electrons in atoms don't radiate. In fact a postulate in QM states that a particle doesn't even have a position until its measured.
When the waves make contact they be viewed as 2 helices or a vortices rather than sinusoidal electric and magnetic waves ...
What are you basing that assertion on? Waves merely add together and interference results.
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The formulae for a helix is along the lines of x = sin(t) y = cos(t) Z = t, which are the equivalent of maxwells idea re electro magnetic radiation.
That's merely the parametric equation for a curve. It's not the expression for an electromagnetic wave. All electromagnetic waves (except in special circumstances such as certain modes in a waveguide) have no component of either the E or B field in the direction of the flow of energy, i.e. in the direction that the wave is moving.
.. electons orbit around a nucleus and will present a +ve then a -ve polarity in space which will generate a pulsating electric field ...
As I said in my first post that is incorrect. Electrodynamics, as you appear to be familiar with it, does not behave according to Maxwell's equations at the subatomic level. At that level you have to use Quantum Electro Dynamics (QED), i.e. the quantum theory of radiation. I explained that in my previous post and you ignore it. May I ask why?
which will of course on average cacel out but not without generating an electromagnetic wave, I think Debroglie assigned a frequency to all matter, relating E = hf, I dont know how to assign this to a planet.
That's only meaningful for objects at the atomic level, i.e. elementary particles, atoms and molecules. It's not meaningful for macroscopic objects such as particles of dust, cars, planets etc.
But im pretty sure if an atoms transmitting radio waves it will do it if its an atom in space or viewed from the size of a planet in space. As I think i said my maths is a bit rusty.
I'm sorry to tell you this but everything you've said is wrong. You'll have to study quantum mechanics to understand why.
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One last thing QEd is on the minute scale, i used the bohr model to try to make it clear what i was talking about.
There are two problems with that (1)your assertions/assumptions are wrong. I.e. they don't correspond to reality and (2) the Bohr model is wrong. That's why it was replaced with quantum mechanics. Bohr constructed a model of the hydrogen atom in an attempt to predict the observed spectrum of hydrogen. He depicted the hydrogen atom as a small, positively charged nucleus surrounded by an electron that travel in circular orbits around the nucleus. The problem with the Bohr model is that it predicts that the atom will radiate a continuous spectrum as the electron spirals in as it looses energy and will collapse after a short time, i.e. about in about 16 picoseconds. To resolve this problem Bohr imposed two postulates. The first one postulated that the electron could only move in certain orbits, known as stationary states, without radiating. The second postulate requires that the atom can only radiate when it makes a transition from one stationary state to another.
Therefore QED ISNT applicable therefore you missed the point. [:)]
You're quite wrong claiming that QED isn't applicable is wrong. Actually its quantum mechanics that really applies here, not QED in particular since we're talking about atoms. QED is quantum mechanics of electrodynamics so in that sense it applies. But to study the hydrogen atom one uses quantum mechanics. And then you can learn what you need to know about the radiation they emit. And they don't emit radiation in the form of continuous waves but as photons, i.e. particles if light. But I most certainly didn't miss the point. However your point is incorrect since, and I'm sorry to say it like this so please forgive me, because you don't understand quantum mechanics.
Also your visualization, for lack of a better word, of an EM wave as a parametric trajectory is quite wrong. In general there's never a requirement for and EM wave to be sinusoidal but when the motion of the source is sinusoidal then so is the radiation. But on the atomic level particles are not things that have a position as a function of time. That's classical mechanics.
I suggest that you read a book on quantum mechanics.
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One last thing QEd is on the minute scale, i used the bohr model to try to make it clear what i was talking about. Therefore QED ISNT applicable therefore you missed the point. [:)]
The problem with the Bohr model is that it predicts the emission of EM radiation, which doesn't happen. Therefore it's a bad starting point for any further discussion and has little scientific value. Quantum mechanics builds mathematical models of what actually happens, and is very useful.
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The problem with the Bohr model is that it predicts the emission of EM radiation, which doesn't happen.
Yeah, but Alan! As I explained above, to "solve" that problem Bohr forwarded two postulates. The first one postulated that the electron could only move in certain orbits, known as stationary states, without radiating. The second postulate requires that the atom can only radiate when it makes a transition from one stationary state to another. I.e. Bohr in effect postulated that Maxwell's laws don't hold at subatomic levels.
This is all explained at: https://en.wikipedia.org/wiki/Bohr_model
Also, as the electron spirals inward, the emission would rapidly increase in frequency as the orbit got smaller and faster. This would produce a continuous smear, in frequency, of electromagnetic radiation. However, late 19th century experiments with electric discharges have shown that atoms will only emit light (that is, electromagnetic radiation) at certain discrete frequencies.
To overcome this difficulty, Niels Bohr proposed, in 1913, what is now called the Bohr model of the atom. He suggested that electrons could only have certain classical motions:
1.Electrons in atoms orbit the nucleus.
2.The electrons can only orbit stably, without radiating, in certain orbits (called by Bohr the "stationary orbits"[5]) at a certain discrete set of distances from the nucleus. These orbits are associated with definite energies and are also called energy shells or energy levels. In these orbits, the electron's acceleration does not result in radiation and energy loss as required by classical electromagnetics. The Bohr model of an atom was based upon Planck's quantum theory of radiation.
3.Electrons can only gain and lose energy by jumping from one allowed orbit to another, absorbing or emitting electromagnetic radiation with a frequency ν determined by the energy difference of the levels according to the Planck relation: ...
Therefore it's a bad starting point for any further discussion and has little scientific value.
Quite true.
Quantum mechanics builds mathematical models of what actually happens, and is very useful.
Also quite true.
However I myself sometimes visualize the atom in terms of the Bohr model. Textbooks on electrodynamics often use that model to visualize the cause of magnetism in terms of the electron creating a current as if moves around the nucleus, thus creating a magnetic dipole moment. So its not as if it can't be found and utilized in elementary ways when visualizing some processes.
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Hmm. I thought atomic magnetism was all about unpaired spins, not orbits, and electromagnetism was all about delocalised charge carriers.
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Hmm. I thought atomic magnetism was all about unpaired spins, not orbits, and electromagnetism was all about delocalised charge carriers.
The atomic currents that I'm referring to are called Amperian currents. Does that ring a bell? Also, as I sure you know, there are various forms of magnetism, i.e. diamagnetism, paramagnetism and ferromagnetism.
This is discussed in Modern Electrodynamics by Andrew Zangwill. This is an excellent text by the way. I think that it was David Griffiths that recommended it to me. It's new on the EM textbook scene. It was published in 2013.
Zangwill talks all about this starting on page 499 in the section entitled Orbital Magnetization
Ampere was the first to suggest that microscopic "molecular currents" are responsible for the magnetic fields produced by matter. Today, we understand this to be true for systems where an external field is needed to bias the direction of microscopic or macroscopic circulating currents to produce a non-zero net magnetic moment. In quantum mechanics, every electron in an eigenstate with orbital wave function Psi(r) contributes a steady, dissipationless, current density
(13.8) <Author gives current density in terms of wave function, i.e. jk(r) = ...>
Each jk(r) describes a closed current loop and thus a magnetic moment.
If you'd like you can read the entire section in it. You can download the text from:
http://bookos-z1.org/book/2066342/cb9a5f
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two atoms ...both with electrons spinning around them in a clockwise direction cause attraction
Electrons don't follow a fixed, 2-dimensional orbit like a planet around the Sun. They fill a certain volume around the atom, and all we know is the probability that they will be found in a particular position.
However, electrons do have a small magnetic field (as does the Hydrogen nucleus). In a covalent bond (https://en.wikipedia.org/wiki/Covalent_bond) between two hydrogen atoms, you can imagine two electrons "pairing up" as opposing magnets, bringing the two hydrogen atoms together as a hydrogen molecule. They are still distributed in a cloud around the hydrogen nuclei, but at room temperature, a hydrogen molecule has a lower energy state than two separate hydrogen atoms.
If Antimatter had an anticlockwise spin it would be repelled from matter.
Antimatter annihilates very rapidly with matter: the lifetime of "positronium (https://en.wikipedia.org/wiki/Positronium)" is around 125 picoseconds. They don't repel.
all matter having a clockwise spin would attract
Just as electrons with opposite spin can pair up, releasing energy, so the magnetic fields of the electron and nucleus can be aligned in the same or opposite directions, with a small difference in energy. This produces the 21cm hydrogen line (https://en.wikipedia.org/wiki/Hydrogen_line), used in radio astronomy to detect clouds of neutral hydrogen atoms in space.
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PmbPhy: I) your assertions/assumptions are wrong, (2)the Bohr model is wrong, (3)quite wrong (4)claiming that QED isn't applicable is wrong, (5) as a parametric trajectory is quite wrong, (6) your point is incorrect since,(7) you don't understand
Well obviously Thor had nothing on the above post; seven instances in one tiny post of about seven lines!
PmbPhy: The first one postulated that the electron could only move in certain orbits, known as stationary states, without radiating. The second postulate requires that the atom can only radiate when it makes a transition from one stationary state to another.
You forgot to mention that when an electron is revolving around the nucleus it is a charged particle that is accelerating and should therefore be radiating. It won’t stop radiating just because someone states that electrons in such and such orbits never radiate. Why the orbiting electron doesn’t radiate is one of the foremost reasons fr the introduction of wave-particle duality. Feynman claims that the oribiting electron is continually emitting and absorbing ‘virtual’ electrons and this hypotheses is supported by the empirical evidence provided by the Lamb Shift experiment. This is almost a classical explanation for why the electron does not lose energy and plummet into the nucleus, it is constantly regulating its energy through emission and absorption of ‘virtual’ electrons. I maybe wrong about this and I am pretty sure going by the evidence that you won’t be shy about telling me so BUT think about it, maybe its you that is wrong once in a way.
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You forgot to mention that when an electron is revolving around the nucleus it is a charged particle that is accelerating and should therefore be radiating.
That is incorrect. You're confusing classical physics with quantum physics. As explained thoroughly above, the undisturbed atom doesn't radiate electromagnetic energy as it would from an accelerated electron because when it is "unwatched," the electron cannot be thought of as an accelerated particle in an orbit. All physicists learn this in their second year of undergrad study. It's basic to quantum mechanics. In fact it was problems such as this that spurred physicists into creating quantum mechanics. If the electrons really did move in classical planet like orbits (which they don't - the Bohr model is wrong) then the electron would spiral into the nucleus in 16 picoseconds. Matter simply wouldn't exist as we know it because atoms wouldn't be stable.
If you really want to learn more about this rather than merely claim that quantum mechanics is wrong then see:
http://www.physlink.com/Education/AskExperts/ae688.cfm
It won’t stop radiating just because someone states that electrons in such and such orbits never radiate.
This is where you need to learn more about quantum mechanics.
Why the orbiting electron doesn’t radiate is one of the foremost reasons fr the introduction of wave-particle duality.
That's correct.
Feynman claims that the oribiting electron is continually emitting and absorbing ‘virtual’ electrons and this hypotheses is supported by the empirical evidence provided by the Lamb Shift experiment.
Wrong! Also, the Lamb shift has nothing to do with this. Where on Earth did you get such a notions from?
The explanation of this problem was given by quantum mechanics when Feynman was a child. It has absolutely nothing to do with virtual particles. In any case virtual electrons is not the kind of radiation emitted by accelerating electrons. And virtual particles don't even exist. That's why they're called "virtual". They're simply a concept which is used to help with the mathematical constructs of quantum field theory. I.e. see: https://en.wikipedia.org/wiki/Virtual_particle
In physics, a virtual particle is an explanatory conceptual entity that is found in mathematical calculations about quantum field theory.
I maybe wrong about this ...
I'm sorry to be the one to inform you of this but you are most definitely wrong about this. Sorry.
..and I am pretty sure going by the evidence that you won’t be shy about telling me so BUT think about it, maybe its you that is wrong once in a way.
Believe me when I say that (1) I only post when I'm certain that I know what I'm talking about and (2) if I'm wrong I immediately admit it. In fact, you can ask anybody about that. In fact someone just commented on that fact the other day in my "select membership" forum.
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That is incorrect. You're confusing classical physics with quantum physics. As explained thoroughly above, the undisturbed atom doesn't radiate electromagnetic energy as it would from an accelerated electron because when it is "unwatched," the electron cannot be thought of as an accelerated particle in an orbit. All physicists learn this in their second year of undergrad study.
This reasoning seems to be right out of George Berkeley, Bishop of Cloyne, also known as Bishop Berkeley, the Irish- English Philosopher, who claimed that when the Universe was unwatched it existed only in the mind of God. In his treatise The Principle of Human Knowledge– he remarked:
” All the choir of heaven and furniture of earth - in a word, all those bodies which compose the frame of the world - have not any subsistence without a mind. George Berkeley
One may agree with this statement OR disagree with it BUT there is one crucial difference; in philosophical arguments it is not allowed to say ‘you are wrong’ or ‘that is wrong’ because if something like that is said then it would have to be shown why it was said and on what grounds. Since, the question of whether an electron might or might not radiate according to whether it was being observed or not is very much a debatable topic, the use of the term ‘you are wrong’ or ‘you are incorrect’ might be too strongly worded for a philosopher.
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One may agree with this statement OR disagree with it BUT there is one crucial difference; in philosophical arguments it is not allowed to say ‘you are wrong’ or ‘that is wrong’ because if something like that is said then it would have to be shown why it was said and on what grounds. Since, the question of whether an electron might or might not radiate according to whether it was being observed or not is very much a debatable topic, the use of the term ‘you are wrong’ or ‘you are incorrect’ might be too strongly worded for a philosopher.
Where did all this talk of "philosophy" come from? This is about physics, not philosophy. And it's a matter of observation and not opinion whether an atom radiates as you suggest. The spectra of atoms are discrete, not continuous and that means that they radiate in terms of photons and not continuous radiation from accelerating photons. Also if what you said was right, as I keep explaining twice already, atoms can't exist. They'd decay by the electrons spiraling into the nucleus in a few picoseconds. I can also be shown using quantum mechanics merely from the axioms. That's why I said you have to learn quantum mechanics to really understand this.
In quantum mechanics there is no mechanism for atoms to radiate in the manner which you described and its for that reason that it can be said to have been shown. It's tricky since you can't prove a negative.
Do mind if I ask you a question? If so then may I ask why haven't you substantiated anything that you've asserted so far? I.e. what evidence do you have that electrons radiate in that manner? Why don't the atoms collapse when all the energy is radiated away?
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Some of what i note has recently be confirmed on some atom basher a recently. Ie photons can recombine producing higher energy atoms.
Where did you read this?
Space is made up of dipole magnets which can exist all the time come into existence and disappear it doesnt matter.
What? Since when?
Due to random events these little dipoles join together aquiring energy so that we become aware of their mass, if the spin pole over pole they are photons if they spin radially they are either electrons or positrons, if they join together in a toroid shape they can become protons neutrons have trapped an electron.
Where did all of this come from? None of it is true.
Sorry had too mmuch to drink and was annoyed by some teling me that qed is scientific fact andd not a useful mathemmatical tool to give useful answers fopr something you dont understand.
Who said that and why do you object to it? Who said it was math for what someone doesn't understand?
You sure do post a lot of unfounded assertions.
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I have more assertionds than you would believe,. my wife has recently checked my spelling and suggested i shouldnt fuel my head with drink. Kind regards Aquarius. Debate to follow, ? ride the wave or be sucked back by the undercurrent. xxxxxc
Wonderful. May we now assume that we've fully addressed your question to your satisfaction? If so then I myself have no desire for a debate after we've answered your questions to your satisfaction.
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If you view two atoms seperated by space say the hydrogern atom, both with electrons spinning around them in a clockwise direction
False, electrons don't do that in the hydrogen atom (at least in the fundamental level as you intend). they will in effect be emitting eltromagnetic waves towards and away from each other.
But they don't; deal with it. When the waves make contact they be viewed as 2 helices or a vortices ...
You are going off on a tangent, here. I suggest you to study physics at university, if you really want a correct description of the subatomic world.
And don't write silly sentences as "Ok I do have a book on QED and String theory i was starting to read , ill get on reading it and maybe come back in a couple of weeks". Given the level of knowledge of quantum physics you show in your posts (very close to zero), it's totally improbable that you could learn such subjects "in a couple of weeks".
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lightarrow
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Sorry had too mmuch to drink and was annoyed by some teling me that qed is scientific fact andd not a useful mathemmatical tool to give useful answers fopr something you dont understand.
Drink and clear thinking don't mix. QED is scientific fact, maths has always been an integral part of science.
We might think we understand Newton's laws of motion just because we can draw pretty pictures of billiard balls, but without the maths we can't predict what will happen and when. It gets complex when there are lots of billiard balls in 3d and they don't behave as in classical dynamics.
probability is a mathematical workaound for something you dont understand,
That's not true. One of the biggest pitfalls in probability is not understanding the system you are trying to work with.
Probability is a very scientific and well proven tool. If we want to study the behaviour of traffic at a complex interchange, we could try to model the behaviour of individual cars, start time, acceleration, stopping for a newspaper, etc. However, if we make sufficient observations we can use probability to make very accurate predictions of traffic flow, but we don't need to know the colour, make and model of every individual car.
QM is very successful at predicting the behaviour of atoms and molecules. Currently, no one has come up with an alternative that gives the same degree of accuracy.
Some of what i note has recently be confirmed on some atom basher a recently. Ie photons can recombine producing higher energy atoms.
I think if you go to the original research you'll find it doesn't say what you think.
Under normal circumstances photons don't join together to form atoms.
The experiment you are thinking of was performed at close to 0 K and showed some interesting interactions between molecules and photons.
I'm quite sure that future experiments will teach us a great deal about the nature of particles. I'm particularly interested in what is being done with weak interactions, these experiments are beginning to show significant results, some early ones even confirm the wave nature of the photon's probability.
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And don't write silly sentences as "Ok I do have a book on QED and String theory i was starting to read , ill get on reading it and maybe come back in a couple of weeks". Given the level of knowledge of quantum physics you show in your posts (very close to zero), it's totally improbable that you could learn such subjects "in a couple of weeks".
ROTFL. Normally I despise your sarcasm but in this case its hilarious, because its so true!