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Why Planck's Formula For Black Body Radiation Is Used To Measure The Cbr?


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#103 exchemist

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Posted 02 June 2019 - 03:06 PM

As it seems to be relevant to the contentions of Marmet, I thought I would post a link to this discussion from physics stack exchange about why a gas cannot be a black body: https://physics.stac...atter-and-gases

 

Marmet seems to have the idea that all matter emits what he calls Planck radiation. It appears that it does not. 



#104 exchemist

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Posted 02 June 2019 - 03:13 PM

1) It refers to the real origin of CBR: BBT or random noise?

3) Depth is meant to measure the thickness (within the visible universe's spherical volume) from which we can detect

    the strongest and the faintest components of CBR below 1 Thz. As EM radiation is under the inverse square law, there

    are max and min values which are detectable. Everything below min values is power undetectable, because it's below the

    noise threshold of our receivers (which have several sources of noise by themselves).

4) It's an undue answer, because the bullet shouldn't be there, and the paragraph is an extension of 3).

5) We can suggest. We are free people and laws don't forbid us to think.

1) no obviously it is not noise. The radiation temperature is clear. Ocean Breeze has even picked it up on his research ship. It is the tiny inhomogeneities in it , of the order of a hundred thousandth of the signal itself, that are hard to detect accurately.

 

3) I still do not know what you mean by "thickness", nor do I understand why the inverse square law is relevant. That is relevant to emission from a point source, but this radiation comes from all over the sky.

 

5) Sure you can. So long as you account for the observations and make predictions for testing the alternative hypothesis.   



#105 Flummoxed

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Posted 03 June 2019 - 03:04 AM

As it seems to be relevant to the contentions of Marmet, I thought I would post a link to this discussion from physics stack exchange about why a gas cannot be a black body: https://physics.stac...atter-and-gases

 

Marmet seems to have the idea that all matter emits what he calls Planck radiation. It appears that it does not. 

 

I double check everything, especially on physics stack exchange, where contradictory answers thrive. Planck radiation is emitted by all matter according to wiki and every other source I looked up. https://en.wikipedia...ki/Planck's_law

 

It appears matter does emit planck radiation.

 

Marmets theory seems plausible http://www.newtonphy...smic/index.html and might be worth a full and proper discussion. 



#106 exchemist

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Posted 03 June 2019 - 03:27 AM

I double check everything, especially on physics stack exchange, where contradictory answers thrive. Planck radiation is emitted by all matter according to wiki and every other source I looked up. https://en.wikipedia...ki/Planck's_law

 

It appears matter does emit planck radiation.

 

Marmets theory seems plausible http://www.newtonphy...smic/index.html and might be worth a full and proper discussion. 

I did that too, but view that Wiki article with a little scepticism, as it talks in generalities about the emission/absorption process and does not seem to deal with the specifics of gases at all.

 

Whereas I can see the guy on stack exchange knows his stuff. He is mentioning all the different ways that the (electronic) band absorption and emission of molecular gases might stretch into broader regions of the spectrum, (via Doppler broadening, red shifts etc), to make the gas seem more like a black body, but even after doing this it is clear they cannot be.

 

I have also checked other sources, as I could not see how a non-polar diatomic gas could possibly emit and absorb so-called "Planck radiation". What I have found is that indeed they can't. So it seems to be an untrue statement that "all matter" emits and absorbs Planck radiation. 

 

If you think about it, this fits with the observation that on Earth, temperature decreases with altitude. Air is heated by the ground, not by heat from the sun passing through. That is because the main constituents N2, O2, have no way of absorbing the radiation.  

 

I have read Marmet's article and find it highly unconvincing. It seems littered with errors. Our previous conversation about atomic and molecular hydrogen provides another example. I was explaining how the formation of molecular hydrogen is actually quite difficult in the very rarefied environment of interstellar space. But Marmet claims, contrary to everybody else*, that there is actually lots of molecular hydrogen and we just can't detect it because it is transparent - but then claims it emits "Planck radiation", which I don't believe it can do, for the reasons I've just given. So he seems to me to be trying to have it both ways and defying physics in the process.  

 

So frankly I'm not surprised he got sacked from his academic job and resorted to self-publishing stuff. I expect he went a bit crazy - certainly looks that way to me. This article of his simply does not appear at all credible, at any rate, to this physical chemist :).

 

 

 

* Acc Wiki, the interstellar medium of the Milky Way is <1% molecular hydrogen: https://en.wikipedia...rstellar_medium


Edited by exchemist, 03 June 2019 - 03:43 AM.


#107 Flummoxed

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Posted 03 June 2019 - 04:47 AM

I did that too, but view that Wiki article with a little scepticism, as it talks in generalities about the emission/absorption process and does not seem to deal with the specifics of gases at all.

 

Whereas I can see the guy on stack exchange knows his stuff. He is mentioning all the different ways that the (electronic) band absorption and emission of molecular gases might stretch into broader regions of the spectrum, (via Doppler broadening, red shifts etc), to make the gas seem more like a black body, but even after doing this it is clear they cannot be.

 

I have also checked other sources, as I could not see how a non-polar diatomic gas could possibly emit and absorb so-called "Planck radiation". What I have found is that indeed they can't. So it seems to be an untrue statement that "all matter" emits and absorbs Planck radiation. 

 

If you think about it, this fits with the observation that on Earth, temperature decreases with altitude. Air is heated by the ground, not by heat from the sun passing through. That is because the main constituents N2, O2, have no way of absorbing the radiation.  

 

I have read Marmet's article and find it highly unconvincing. It seems littered with errors. Our previous conversation about atomic and molecular hydrogen provides another example. I was explaining how the formation of molecular hydrogen is actually quite difficult in the very rarefied environment of interstellar space. But Marmet claims, contrary to everybody else*, that there is actually lots of molecular hydrogen and we just can't detect it because it is transparent - but then claims it emits "Planck radiation", which I don't believe it can do, for the reasons I've just given. So he seems to me to be trying to have it both ways and defying physics in the process.  

 

So frankly I'm not surprised he got sacked from his academic job and resorted to self-publishing stuff. I expect he went a bit crazy - certainly looks that way to me. This article of his simply does not appear at all credible, at any rate, to this physical chemist :).

 

 

 

* Acc Wiki, the interstellar medium of the Milky Way is <1% molecular hydrogen: https://en.wikipedia...rstellar_medium

 

 

Whilst the wiki link you posted above indicates < 1 % molecular hydrogen :)  it appears to contradict some of your other conclusions above and since it is generally accepted wiki is a dodgy source.

 

I dug up a better link on the interstellar medium. H2 can not be detected directly, but it does exist in dark clouds in space http://casswww.ucsd....orial/ISM.html 

 

Edit when H1 binds with H1 to form H2 it is exothermic, and will give of radiation.


Edited by Flummoxed, 03 June 2019 - 04:49 AM.


#108 exchemist

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Posted 03 June 2019 - 05:43 AM

Whilst the wiki link you posted above indicates < 1 % molecular hydrogen :)  it appears to contradict some of your other conclusions above and since it is generally accepted wiki is a dodgy source.

 

I dug up a better link on the interstellar medium. H2 can not be detected directly, but it does exist in dark clouds in space http://casswww.ucsd....orial/ISM.html 

 

Edit when H1 binds with H1 to form H2 it is exothermic, and will give of radiation.

It's certainly possible it contradicts something I've said. I don't claim to be an astrophysicist, merely a physical chemist who can usually read and understand physical science from other disciplines. I'd be very interested to know what in detail. Can you give an example?  

 

I can't open the link, unfortunately. Does it come up with a higher abundance of H2 than Wiki?

 

Lastly, I notice this is the second time you have asserted that radiation is emitted when 2 hydrogen atoms combine to form a molecule. Can you provide evidence for this claim? I have some difficulty with the idea, for the reasons I have explained. 



#109 exchemist

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Posted 03 June 2019 - 06:34 AM

It's certainly possible it contradicts something I've said. I don't claim to be an astrophysicist, merely a physical chemist who can usually read and understand physical science from other disciplines. I'd be very interested to know what in detail. Can you give an example?  

 

I can't open the link, unfortunately. Does it come up with a higher abundance of H2 than Wiki?

 

Lastly, I notice this is the second time you have asserted that radiation is emitted when 2 hydrogen atoms combine to form a molecule. Can you provide evidence for this claim? I have some difficulty with the idea, for the reasons I have explained. 

QUOTE:

In May 1999, the head of the physics department came to Marmet’s office and said: “Ce n’est pas ton bureau que nous voulons, ton problème est que tu remets en question les principes fondamentaux de la physique.”   (“We do not want your office,  your problem is that you keep questioning the fundamental principles of physics.”)  Three months later, a letter was sent requiring Marmet's office to become unoccupied before the end of the month. 

 

UNQUOTE



#110 exchemist

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Posted 03 June 2019 - 06:57 AM

I deleted a post defending Marmet, where I said that he hadn't been sacked.

 

He was sacked, indeed. He explain it by himself at his site, mantained by his son and others:

 

http://www.newtonphy...nfo/author.html

 

Quote from the son's Obituary:

 

  His interest in astronomy led him to study the numerous anomalies observed by astronomers, especially the inconsistent redshifts reported in the works of H. Arp.  To explain these anomalies, Dr. Marmet suggested that an energy loss mechanism resulting from dipole emission could leave the same signature on spectral absorption lines as the Doppler redshift.  The dipole is created by momentum transfer of a photon in its interaction with a single molecule in a low density gas.  Observations of massive quantities of molecular hydrogen by the European Space Agency's Infrared Space Observatory confirms there is enough interstellar gas to support his hypothesis that the cosmological redshift is not entirely of Doppler origin.  The mechanism still waits for a detailed quantum mechanical development and experimental verification in the laboratory.  He also proposed other models to explain non-intuitive quantum mechanical phenomena and relativity.  He is said to be a strong critic and a mighty rebel in physics.  He leaves many incomplete ideas and many colleagues still wishing to discuss with him.

He will be missed as a good experimentalist and also as my father.

 

----------------- End of quote-------

 

No wonder he was black-listed. He followed theories from Halton Arp, a bigger figure than him in the fight against "stablishment's dogmas".

 

The history of his final years adventure is related by his son (I pressume and quote):

 

In 1997-99, physicists of the establishment showed fierce disagreement with the fact that Marmet’s research implied that the fundamental principles of physics were being questioned.  Although the experimental work, which could determine the energy of numerous quantum stated was highly appreciated and even honored, the physics establishment required that the author should stop questioning the fundamental principles of physics.  The author was first informed by NSERC (Natural Science and Engineering Research Council of Canada) to stop doing that fundamental research despite the fact that, being theoretical, it required no research funds - all research grants were used for the experimental work needed for the electron impact apparatus.  Since the fundamental research was still going on the following year, the grant was cut to zero, putting an end to experimental work using the monoenergetic electron beams. 

  In May 1999, the head of the physics department came to Marmet’s office and said: “Ce n’est pas ton bureau que nous voulons, ton problème est que tu remets en question les principes fondamentaux de la physique.”   (“We do not want your office,  your problem is that you keep questioning the fundamental principles of physics.”)  Three months later, a letter was sent requiring Marmet's office to become unoccupied before the end of the month.  Without research grant and being expelled from his office, Dr. Marmet continued his research alone at home.

  This was the irrevocable death of a unique instrument in the world, which was able to measure the electronic structure of negative ions and their ionization efficiency curve using a high resolution monoenergetic electron beam.  A few months later, the instrument was destroyed.  Also, this shows that physics is not only a science, it is a doctrine.  Therefore, there are heretics.   It's not different from Galileo’s time!

 

--------------------------------

 

More clear than this, impossible.

 

Stablishment (tptb) doesn't like to fund dissidence. Only coincidence.

Yes, he was sacked. From reading the linked article we have been discussing I am not surprised. 

 

What is curious about Louis Marmet's obituary is that he talks as if the cosmological redshift is of Doppler origin. Looks as if the poor physics has continued from father to son.  


Edited by exchemist, 03 June 2019 - 07:07 AM.


#111 exchemist

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Posted 03 June 2019 - 08:24 AM

exchemist, I have a question for you regarding how the whole thing of CBR started 80 years ago.

 

Back in the late '30s and early '40s, some "cosmologists" (it wasn't an stablished branch of astronomy yet) theorized about the average

temperature of the whole universe, discounting the hot spots that galaxies were.

 

Out of our earthly understanding of temperature, related to the kinetic theories of gaseous atmosphere, to talk about temperature in the

space is a very tricky subject, because only theories of radiating heat can apply (as far as I know).

 

There are two formulae which are used in astrophysics, when temperature is an issue, and both are related directly to radiation.

 

The oldest one (Stefan, 1879) is very simple and connect radiating power per unit area with the fourth power of temperature (in °K). It was used

by Stefan himself to estimate the Sun's surface temperature 150 years ago, and remain as an undisputed tool in astrophysics to derive a lot of

info about stars (temperature, size, luminosity) even today.

 

The second one (Planck, 1901) is quite more complex because it involves statistical behaviors (Maxwell-Boltzmann-Gibbs statistical mechanics).

The complexity lies in its three components: 1) the amount of resonance modes of EM waves inside a cavity (independant of temperature); 2) the

unit energy quantum of a given EM wave (h.f) and 3) the statistical distribution of energy along the spectrum, which is the exponential part that

makes the difference between Rayleigh's PDF (flat) and Planck's PDF (gaussian like curved shape being function of f and T).

 

I'd like very much if you help to reconstruct the history of the current CBR behavior, starting with the original thoughts of the first ones who dared

to approximate a value of average temperature for the whole universe. The values that appeared between the 30's and the 50's varied in a wide

range between 4°K and 50°K.

 

My question to you is this: What theory did the early cosmologists used to estimate the temperature of the universe?

 

I think that they should have worked very hard to discount "singularities" in the isotropic conception of the universe, like the billion-trillions of galaxies

which were not meant to be considered. It was already known by then that distances between galaxies were huge, in the order of tens of Bly. So,

assuming that they discounted the accumulated energy of such hot-spots into the "volume" of the universe, the above question is:

 

Did they approximated results by Stefan? Did they averaged part of the Planck's spectrum (area under the curve)? Another theory that I'm not aware of?

 

I'd really appreciate your comments about the early stage of the development of the CBR theory that we know today.

Sorry, no. I am not a cosmologist and have neither the time nor the interest to go digging through the history to see how estimates of "temperature", if there were any, may have been arrived at. But there is nothing stopping you from doing that and providing us with the most concise and clear links you can find.  

 

All I can do is try to keep the physics and chemistry people use in these discussions more or less on the rails, to the best of my ability.

 

You are quite right that temperature is indeed a dodgy concept in interstellar space. The atoms and molecules are too far apart for a thermal equilibrium energy distribution to be set up. Without that, temperature is undefined.

 

This is yet another reason to be suspicious of our friend Marmet, with his imagined and highly dubious clouds of molecular hydrogen, which he thought can magically radiate like a black body, even though they have no dipole (i.e. no appropriate "oscillator" in black-body-speak) and would thus be transparent in the microwave and IR regions.     


Edited by exchemist, 03 June 2019 - 08:26 AM.


#112 exchemist

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Posted 05 June 2019 - 09:38 AM

After a long thread questioning why Planck's formula for Black Body Cavity Radiation was

being used to describe the Cosmic Background Radiation, this post is the final in this journey.

 

The next figure represents the instrumentation used at COBE's FIRAS to measure the CBR.

 

I've been researching about the kind of instrumentation used on-board at COBE satellite, and

all remits to the 1946 R. Dicke's paper where he proposed to mix and substract Planck's noise

from CBR, by using a switching amplifier plus a mixer plus a "Dicke bolometer". He patented it.

 

In few words, his instrumentation substracts Planck's noise (from references) from the received

CBR. He does so by amplifying the differences between Planck's noise and the CBR, and the

difference is amplified and "read" using a "Dicke's bolometer". This allowed to see anisotropies.

 

As Dicke's assumption (and also NASA's assumption) is that CBR has the form of Planck's

radiation, everything what was done was a "self-fulfilling" prophecy, so it's fallacious.

 

And, as I suspected, everything around COBE, WMAP and PLANCK's satellites and the results

for the detailed measurement ARE WRONG, FALSIFIED.

 

Every time this kind of measurements were performed, on Earth or in outer space, there was a

prior assumption that it SHOULD FOLLOW Planck's radiation.

 

After all, the genial Planck provided the only available formulae to predict radiation spectra of a

black body cavity as a function of frequency and absolute temperature. Science HAS NOT any

other alternative than using this theory, even when Planck would disapprove it, because it's a

violation of the Kirchoff's theorem, which driven the search for an answer for the second half

of the XIX century among thermo-electro-dynamicists.

 

Sad, but true: The basis for the Big Bang Theory ARE FALSIFIED. And everyone has to shut up.

 

Dicke%2BBolometer.jpg

What is Planck's "noise", please? I am not familiar with this term.



#113 VictorMedvil

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Posted 05 June 2019 - 11:56 AM

I agree with dubbel this entire thread is cranky, whenever you hear the term self-fulfilling prophecy outside time travel paradoxes you know it to be crank. cranks to the left of em, cranks to the right of em.


Edited by VictorMedvil, 05 June 2019 - 11:57 AM.

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#114 Dubbelosix

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Posted 05 June 2019 - 05:03 PM

Dubbelosix, I wanted you to know that I'm putting you in my Ignore List once I finish this post.

 

I don't want to trigger you or hurt in anyway your feelings, so I consider that this is the best thing to do.

 

First time ever that I use this feature.

 

The audacity to repeat such a claim in two different posts, shows me you are nothing but an attention seeker, but I hold by my word... either the thread is removed or closed in a few days time, or I leave.



#115 Flummoxed

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Posted 01 July 2019 - 03:00 AM

It's certainly possible it contradicts something I've said. I don't claim to be an astrophysicist, merely a physical chemist who can usually read and understand physical science from other disciplines. I'd be very interested to know what in detail. Can you give an example?  

 

I can't open the link, unfortunately. Does it come up with a higher abundance of H2 than Wiki?

 

Lastly, I notice this is the second time you have asserted that radiation is emitted when 2 hydrogen atoms combine to form a molecule. Can you provide evidence for this claim? I have some difficulty with the idea, for the reasons I have explained. 

 

I don't wish to reopen the thread. 

 

Here is the link again, it seems the end of the URL became corrupted http://casswww.ucsd....torial/ISM.html just in case it does it again it should read ISM.html at the end.

 

I understand that to break H2 into H + H requires energy, it seems logical to a none chemist when they come together that they must lose energy. I may be wrong as 

I remember very little about chemistry. 



#116 exchemist

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Posted 01 July 2019 - 03:17 AM

I don't wish to reopen the thread. 

 

Here is the link again, it seems the end of the URL became corrupted http://casswww.ucsd....torial/ISM.html just in case it does it again it should read ISM.html at the end.

 

I understand that to break H2 into H + H requires energy, it seems logical to a none chemist when they come together that they must lose energy. I may be wrong as 

I remember very little about chemistry. 

You are quite right of course about that but the point is how can that energy be lost before the atoms rebound again? In chemical kinetics this is a real issue. Because energy is conserved, when a bond forms the reacting species, by definition, have enough energy to break the bond again and fly apart. In the case of reacting gases at what we think of as normal pressures, the frequency of intermolecular collisions is high enough to provide ways for the energy of what is called the "activated complex" to be redistributed to other molecules before this happens.  

 

But in the hard vacuum of interstellar space this is not so. There will sometime be occasions when there is another molecule is close enough to help do this but it will be fairly infrequent. Yes, the only other available process would be spontaneous radiation, by the activated complex excited state created when the two atoms interact. However I am not sure such a process exists. Bear in mind there are plenty of spectroscopic energy level changes that do NOT occur because they are forbidden by the so called selection rules (rules to do with the symmetry of the wavefunctions before and after)  I can't find evidence for this radiation process.

 

What I do find is research like one: https://ntrs.nasa.go...19730011435.pdf. which is all about hydrogen recombination when there is a third body to stabilise the activated complex.  


Edited by exchemist, 01 July 2019 - 03:18 AM.

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#117 Flummoxed

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Posted 01 July 2019 - 05:39 AM

You are quite right of course about that but the point is how can that energy be lost before the atoms rebound again? In chemical kinetics this is a real issue. Because energy is conserved, when a bond forms the reacting species, by definition, have enough energy to break the bond again and fly apart. In the case of reacting gases at what we think of as normal pressures, the frequency of intermolecular collisions is high enough to provide ways for the energy of what is called the "activated complex" to be redistributed to other molecules before this happens.  

 

But in the hard vacuum of interstellar space this is not so. There will sometime be occasions when there is another molecule is close enough to help do this but it will be fairly infrequent. Yes, the only other available process would be spontaneous radiation, by the activated complex excited state created when the two atoms interact. However I am not sure such a process exists. Bear in mind there are plenty of spectroscopic energy level changes that do NOT occur because they are forbidden by the so called selection rules (rules to do with the symmetry of the wavefunctions before and after)  I can't find evidence for this radiation process.

 

What I do find is research like one: https://ntrs.nasa.go...19730011435.pdf. which is all about hydrogen recombination when there is a third body to stabilise the activated complex.  

 

I am going to have to demonstrate my ignorance. :) At near absolute zero in the near vacuum of space, two H atoms forming H2 would lose potential energy not kinetic/thermal energy to another atom, which is not available in the vacuum of space. If they did not they would just fly apart would they not? Energy comes in the form of kinetic or potential energy. If the process was radioactive, Energy is radiated in the form of either  Alpha, Beta, Gamma or Xrays

 

Gamma and Xray are normally associated with high energy radiation. Alpha radiation is to do with Helium atoms being ejected so is not applicable to hydrogen. That leaves perhaps Beta radiation or some form of very low level EM radiation, as the only mechanism for losing energy when H2 is formed from H in the vacuum of space, at near absolute zero.



#118 exchemist

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Posted 01 July 2019 - 09:12 AM

I am going to have to demonstrate my ignorance. :) At near absolute zero in the near vacuum of space, two H atoms forming H2 would lose potential energy not kinetic/thermal energy to another atom, which is not available in the vacuum of space. If they did not they would just fly apart would they not? Energy comes in the form of kinetic or potential energy. If the process was radioactive, Energy is radiated in the form of either  Alpha, Beta, Gamma or Xrays

 

Gamma and Xray are normally associated with high energy radiation. Alpha radiation is to do with Helium atoms being ejected so is not applicable to hydrogen. That leaves perhaps Beta radiation or some form of very low level EM radiation, as the only mechanism for losing energy when H2 is formed from H in the vacuum of space, at near absolute zero.

Well up to a point. Forget β radiation: that is made up of electrons, so it would leave you with an ion. Forget γ as well, as that is far too energetic and comes from nuclear reactions. X-rays come from very energetic transitions in the cores of multi-electron atoms with high nuclear charge, so these would not be relevant either. No it would have to be some process for photon emission, in the UV I imagine, by which the electrons can lose energy.

 

The problem I see can be illustrated in the molecular orbital diagram in this: https://chem.librete..._Orbitals_of_H2

 

(I tried to cut and paste the diagram but the website won't let me, so you'll have to follow the link.)

 

 

As the 2 atoms approach one another the 2 1s orbitals influence one another and two new molecular orbital states are formed, one bonding and one antibonding. Until some form of energy release can occur, one electron goes into each state, the sum of the energies remains the same as that of the free atoms, and the net bonding effect is zero. So effectively, you are proposing that the electron that starts to find itself going into the antibonding orbital has a radiative process by which it can drop down and join the one in the bonding orbital. 

 

I am saying I am not sure that is possible. Generally, these transitions need to involve a change of one unit of angular momentum, because the emitted photon carries away one unit of angular momentum. So for example in the spectrum of atomic hydrogen, a transition from a p orbital to an s is allowed, but between two s orbitals is forbidden. Such considerations give rise to what are known as the spectroscopic "selection rules", which limit the number of lines you can actually see compared to all the potential combination of changes in state that you could imagine.  

 

It's too glib to say the 2 atoms just radiate away the energy: they may not be able to, because of the laws of quantum physics.  


Edited by exchemist, 01 July 2019 - 09:13 AM.


#119 Flummoxed

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Posted 01 July 2019 - 10:43 AM

 

 

It's too glib to say the 2 atoms just radiate away the energy: they may not be able to, because of the laws of quantum physics.  

 

If H +H cant get rid of energy would they be stable ? H2 is stable, so maybe you are right they lose energy via low level photon emission resulting in very low level radiation throughout all of space.

 

An interesting thing about H2 being hard to detect, it is a candidate for dark matter.  https://principia-sc...tation-anomaly/ which might make Verlindes entropic gravity which I favour on occasion and MOND theories a little tenuous, and amusingly might also call into question the Hot big bang.