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-   -   Elemental Puzzle (https://www.mersenneforum.org/showthread.php?t=5503)

davar55 2010-04-04 15:00

I was wondering: in an element such as Lanthanum (#57) or
Cerium (#58) how are the valence electrons determined to be
s2 and f1 in La or s2 and f2 in Ce, rather than say La=s2d1 or
even Ce=s2p2 or s2d1p1(outside of the context of the surrounding
elements in the periodic table?)

As a whole, how does one distinguish the sub-shell (energy level)?

xilman 2010-04-04 15:14

[quote=davar55;210558]
According to my theory, elements 116,118,120,121, and 122
each have a stable isotope when surrounded by a
complete complement of electrons.[/quote]Stable with respect to which reaction(s)?

As you appear to accept that the actinide elements exist, you don't seem too concerned about stability with respect to beta-decay, alpha decay and spontaneous fission. It's hard to tell from your earlier statements whether other, rarer, reactions are of concern [I]vis-a-vis[/I] existence of elements.
[quote=davar55;210558]
There is a complementarity between protons and electrons,
and it is the mass difference that induces the fact that the
protons are central AND their electric field property generates
the electron shell structure.[/quote]Now you part company with all nuclear physicists, as far as I can tell.

The conventional view is that nucleons interact via the strong force and it is this which allows them to cluster together in the nucleus against the repulsive electromagnetic force between the protons and the nil-to-negligible EM interaction between a neutron and other nucleons.

In the conventional view, mass has relatively little to do with the binding. Replace the proton in hydrogen with a positron and you form a perfectly good atom called positronium. Positronium chemistry is well established and certainly much richer and much better characterized than is, say, Cn chemistry.

Replace the proton in hydrogen with a positive muon and you get muonium. Again, muonium chemistry is well established.

Google will turn up numerous pieces of evidence in support of the above statements.

Paul

sichase 2010-04-05 01:57

[quote=xilman;210542]Good post!

AIUI, Davar has previously used the word "element" in a rather non-standard way. You and I use the conventional term, where it refers to the number of protons bound in the nucleus. He seems to think an element must also be stable when electrically neutral with a full complement of electrons.

Please be a little careful when saying that orbital electrons have "only a few eV of negative binding energy". That is true of electrons which experience only a small effective nuclear charge. So it's true for valence electrons but emphatically wrong for high-Z inner core electrons where binding energies can be many keV. It doesn't alter your conclusion, AFAIK, but I think it pays to state such things precisely.

(Added in edit: actually, K-capture is a well-known mechanism by which a nucleus is stabilized by extra-nuclear electrons. However, K-capture converts one element into another and the electron doesn't remain extra-nuclear. It's inverse, beta-decay, has analogous properties. I suspect that your hypothetical element would also be unstable with respect to K-capture.)

Paul[/quote]

There's no good motivation that I can see for redefining "element" to include any notion of stability. If you did it, what would you gain? The important question (as you know) is what the spectrum of bound states is.

You make an important point about electron binding. I was being sloppy, and three orders of magnitude is a bit much to lose track of, especially in light of the interesting relativistic effects that happen for tightly bound electrons near a high Z^2 nucleus.

Susceptibility to K-capture should depend on the binding energy of the decay product, which I have no way to estimate. At the neutron drip line, giving up a neutron in favor of a proton (e.g., through beta decay) would generally increase stability. At the proton drip line, it's the converse. But a real answer would depend on the details.

If this conversation goes on much further, I'm going to be in trouble. :=) It has been about 15 years since I worked in nuclear physics; my knowledge is stale and, at the moment, all my books are packed up during an office move. So you are going to pull me out into deep water on anything that cannot be Googled!

--Scott

davar55 2010-04-30 16:51

1 Attachment(s)
Here's the latest version of my cosmology monograph. It's been
restructured, retexted, and updated to cover some additional topics.
It's 12 pages long. There are a few more topics I'd like to add,
when I'm prepared to. Comments much appreciated.

lavalamp 2010-04-30 20:00

[quote=davar55]I "claim" that I can "prove" this number of rows, subshells,
and consequently, elements.[/quote]Do it.

CRGreathouse 2010-04-30 21:28

12 pages of fluff. There's no proof or supporting evidence anywhere.

ccorn 2010-06-22 15:27

Big Bang vs. Steady-State
 
I stumbled over this sleeping thread yesterday and spent an afternoon reading through the discussion. It is interesting, mostly because the participants have managed to get some debatable content into this thread.

I agree with the critics that no serious reason for this "New Cosmology" has been brought forward so far. Plainly, it seems to me that inventing new unseen particle types and new unseen dimensions without verifiable predictions, in addition to non-falsifiable propositions e.g. about how exploding black holes might reverse entropy growth, is no promising way to establish anything. However, building up a theory from a small set of axioms and fitting it to facts seems to be a nice and perhaps fruitful try which does not deserve to be ridiculed. After all, string theory does so, too. (Here, I would like to see that black hole/entropy thing excluded from the comparison.)

As you probably also know, sneering about big bang cosmology has been fashionable for the longer part of that theory's history. Initially, the predicted age of the universe according to the first estimates of the Hubble "constant" was less than the earth's age. Had Mersenneforum existed at that time, a proponent of big bang theory would have been torn to pieces here, and rightly so.

Far objects' red shift has been considered with quite a few dissimilar explanations. [url=http://www.ams.org/notices/200101/fea-daigneault.pdf]Here is one of them[/url]. Naturally, it also comes with a different explanation for the cosmic background radiation. I should remark that the creator of that theory is said to have not been respectful for contradicting data either, but his idea is nevertheless refreshing, as it shows that there is yet another way of realizing redshift etc with an understandable model, and that the only way of judging any theory is by matching it with experimental evidence.

My impression from the cosmo1.txt is that its author has a serious desire for a beautiful theory. That's not a bad thing actually. Now, davar55 may or may not like this, but I'd like to point out that the big picture of his so-called "new cosmology" seems to be not so new at all, as it resembles yet another offspring of the steady-state-principle. That principle has had quite a few renowned proponents, and it is not an easy one to sneer about.

There are some problems with steady-state theories in general, however, and at least two of them have shown up here:

First, the idea of a steady-state universe is a very strong hypothesis. By stating that there is no way to derive a definite age or size of the universe, and that its evolutional history is an infinite repetition of the present, steady-state theory is like a relativistic theory on steroids. Among other things, this leads to problems with entropy considerations, as we can see here.

Second, that strong steadyness actually has axiomatic character for its proponents. According to them, strong steadyness shall not be subject to verification by experiment, but taken as a basic principle for any further consideration. "Steady-statesmen" seem to be prepared to fit any part of their cosmology to experimental evidence except for the steadyness principle. In that view, allowing the strength of the steady-state hypothesis to be reduced would mean losing the principle, that is, losing the reason for developing a cosmological model at all. Therefore, any theoretic capriole is undertaken to support the strong steady-state hypothesis.

This reminds us of the epicycle models for planetary motion, held up just in order to still support the idea that any model for planetary motion should be built on circles. With more and more empirical facts challenging the ever more to-be-refined and complicated model, other theories gained attraction. It seems that this has happened in the struggle between big bang and steady-state cosmologies too. Simon Singh has [url=http://www.simonsingh.net/Big_Bang.html]written about that[/url].

I'd like to see this thread taken up again, this time with concentration on empirical facts that actually divide big bang cosmology from steady-state cosmology. Would you contribute?

IMHO redshift and cosmic background radiation do not count by themselves, as they can be (and apparently have been) integrated into steady-state theories. Please recall that the acoustic Doppler effect had to be established by experiment, with velocities made certain by the setup. When reporting on his first systematical observations regarding redshift of distant galaxies, Hubble expressly did not rule out interpretations of the redshift other than a Doppler effect. That is, in order to argument with redshift, you have to come up with experimental data from approaches later than Hubble's time.

Here are the points I can come up with, and they are frightfully few:

* Big bang cosmology does explain the observed ratio of hydrogen to helium in the universe. In a steady-state model, there is no reason for that specific ratio.

* Steady-state cosmology does not explain why we have no quasars in our neighborhood. In big bang cosmology, the universe has a definite age, and quasars are supposed to be phenomena of mostly young, or early, galaxies, hence are more probable when billions of light years away.

Please add to this list.

lfm 2010-06-22 17:42

For me one of the biggest questions about the big bang theory is where did this inflation thing come from. It sure seems arbitrary to me, just tacked on to get from 0 to 1. Like with the supposed infinite density at time zero we are starting with a singularity with no where to go outward from there. It just looks like a bunch of hand waving to get out of it. Like all the constants just become variables with little reason I can see.

Ok,I am not a physicist and nor a mathematician, just a computer programmer. So I guess I will never really understand it.

davar55 2010-12-18 20:32

[quote]For me one of the biggest questions about the big bang theory is where did this inflation thing come from. It sure seems arbitrary to me, just tacked on to get from 0 to 1. Like with the supposed infinite density at time zero we are starting with a singularity with no where to go outward from there. It just looks like a bunch of hand waving to get out of it. Like all the constants just become variables with little reason I can see.

OK, I am not a physicist and nor a mathematician, just a computer programmer. So I guess I will never really understand it.[/quote]It is arbitrary, which was part of my objection to Big Bandwagon too.
This new cosmology as presented in the monograph (eventually I hope
to extend it, if I'm on the right track) rejects a starting point to
existence, hence an origin in time of spacetime. Einstein understood.

davar55 2010-12-25 04:41

[quote=lavalamp;213657]Do it.[/quote]

Actually prove it mathematically, here in the mforum?

Forgive me my keys, but this is principally a math forum.

I will, I hope, eventually provide an updated monograph,
but it's in the works. Stay tuned (not too soon, though).

davar55 2010-12-25 04:48

Previously in this thread:

[quote=cheesehead;188555]Then how does your theory explain the [I]factual observation[/I] that when slow neutrons are falling in vacuo under the influence of gravity, they fall at only certain discrete rates -- that is, that gravitational force has been physically demonstrated to occur only in discrete quanta, not continuously as Newtonian mechanics has it?

(Yes, this was the outcome of an actual experiment in 2001.

[URL]http://physicsworld.com/cws/article/news/3525[/URL]

[URL]http://www.freerepublic.com/focus/fr/610487/posts[/URL])[/quote]

[quote=xilman;188701]So far, so good.
However, this conclusion is not the one I draw from the results of the experiment. My conclusion is that the energies of the neutrons in a gravitational potential well are quantized in accordance with theory.

The experiment says nothing about the quantum structure of the potential well itself. Exactly the same result would have been predicted if gravity is a quantum field or a classical continuous field.
[/quote]

Yes. This cosmology (see the attachment to an earlier post) explains
that gravity is continuous, not discrete.


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