User:Jclerman/sandbox4

Critique of the isotope boxes template

The traditional standard of scientific publications is that tables be accompanied by a caption describing them, how they are generated (thus allowing for their verification), and a glossary of the terms used.

When, like in an encyclopaedia, there are multiple tables of the same kind, a general "help file" or its equivalent is fully acceptable (if an explicit link is provided in the table's caption). Likewise, Wikipedia wouldn't publish either an illustration without a caption or a graph withou a caption and/or lacking explicitly labeled coordinate axes.

In the particular case of the isotope boxes, the "help file" should have shown "nuts and bolts" examples of how to construct a table for each type of radioactive decay and for stable isotopes.

Lacking both a caption and a glossary, the table-naïve reader is confronted with the task of interpreting (right or wrong) the meaning of the boxes in each one of the isotope tables.

The following two cases summarize such interpretations based on the face-value of the text included in the respective boxes.

Similar considerations apply to the tables generated for all other isotopes.

Case #1

For Carbon-14 this table was generated:

a. Nowhere Carbon-14 appears in the table or in a caption to the table. The reader is consequently puzzled.

b. The first column shows the isotope Carbon-13 in its heading, with a box that says "Produced from" Nitrogen-18 and Boron-14. The table-naïve reader lacks an explanation of what's the relationship of these isotopes with Carbon-14, the one that the article is about.

c. The second column titled "Isotopes of Carbon" contains a sole entry which is a link to "Decay chain" leading to "main decay chains (or families) ... observed in nature, commonly called the thorium series, the radium series (not uranium series), and the actinium sëries." Again, the naïve reader can't see the implications of these decay chains for the Carbon-14 isotope decay.

d. The third column titled "Carbon-15" says that it "Decays to" Nitrogen-14 which, again, it's not the article's object, i.e., the isotope Carbon-14.

e. Then the puzzled reader attempts to correlate the boxes in the table with the text of the article. Surprisingly, the article doesn't mention any of these: Carbon-13, Nitrogen-18, Boron-14. The only object common to the table and the text is Nitrogen-14 and the decay reaction given in the text doesn't appear in the table.

f. The table doesn't state whether the given formation reaction applies to natural or artificial production of the isotope. Not a trivial matter for environmental isotopes.

Conclusion:

The table-naïve reader finds that the table and the article present contradictory information about the formation and decay of Carbon-14, and such a decay table as given to be of no use.

Case #2

For Carbon-13 this table was generated:

a. Nowhere Carbon-13 appears in the table or in a caption to the table. The reader is consequently puzzled.

b. The first column shows the isotope Carbon-12 in its heading, with a box that says "Produced from" Nitrogen-13 and Boron-13. The table-naïve reader lacks an explanation of what's the relationship of these isotopes with Carbon-13, the one that the article is about.

c. The second column titled "Isotopes of Carbon" contains a sole entry which is a link to "Decay chain" leading to "main decay chains (or families) ... observed in nature, commonly called the thorium series, the radium series (not uranium series), and the actinium sëries." Again, the naïve reader can't see the implications of these decay chains for the Carbon-13 non-existing decay since it's a stable isotope.

d. The third column titled "Carbon-14" says that it "Decays to" Stable, which contradicts the fact that the isotope Carbon-14 is radioactive, contradicts the information of the second column that says that "Isotopes of Carbon" have a decay chain. Moreover, the reader can't understand why Carbon-14 is listed in a table which presumably is about Carbon-13.

e. Then, the puzzled reader attempts to correlate the boxes in the table with the text of the article, unsuccessfully.

f. The table doesn't state whether the given formation reaction applies to natural or artificial production of the isotope. Not a trivial matter for environmental isotopes

Conclusion:

The table-naïve reader finds that the table and the article present contradictory information about Carbon-13, and such decay table to be confusing if not useless.

General considerations

Before investing time and effort in the next version of the template, consider whether (not in order of importance & not a complete list):

1. Is the generated table fool-proof ?
2. Does the table summarize the text of the article re formation and decay processes ?
3. Does the table contribute new information ?
4. Can the table be correctly parsed faster or better than the text ?
5. Can the reader reproduce the table ?

Exponential decay

I am not sure how to cite this. From what I can tell, mean lifetime really is replacing the notion of half-life.

Where? In general? In math? In electric engineering? In physics of particles? In biology? In ...?

Sure, this is a bit of a general impression. But I doubt I can find any single source that can verify it.

A single source won't do it when you cite opinions rather than facts.

My impression comes from all of the textbooks I have read and all of the professors who have taught me.

Again subjective. My "all" sets (of books and professors) might be smaller or larger than yours and that those of the wikipedia users.

As a matter of fact, I am pretty sure that I have read something directly declaring, "A few older authors on this subject may refer to half-life instead of mean lifetime. Half-life is an outdated term related to the mean lifetime by [formula]."

Don't put quotation marks if it's not a verbatim text AND if you can't provide a verifiable source. When you become a practicing scientist and submit a paper for publication it will be rejected if a quotation is not duly sourced.

I will try to look for the source.

Good. Please, send me scans.

Please help me if you have any better ideas.

I'm trying, that's why I commented on your edits and in your new paragraph (below).

Teply 05:55, 11 June 2006 (UTC)

Jclerman 12:15, 11 June 2006 (UTC)

• I just looked in the introductory physics textbooks that I had around, namely Tipler & Mosca Physics for Scientists and Engineers and Tipler & Llewellyn Modern Physics.

Unfortunately my university library does NOT have these texts. They refuse to purchase market oriented editions that make annual or biannual trivial changes in order to be able to sell frequently updated texts rather than let students rely on "used books". And I have NOT been able to get them from the publisher unless I can prove that I have adopted them for my classes. And Wikipedia does NOT qualify as a class because the definition of a class is "some 40 copies sold". Furthermore, you should try to use better rooted in time and more advanced references, if possible written by practicing scientists. Real world editors of scientific journals wiil require that from you when the time arrives.

Tipler & Mosca uses the mean lifetime for damped harmonic oscillators and RC circuits.

Mean lifetime of what? Not of the oscillator or the circuit. I'd like to see a scan.

Tipler & Llewellyn introduces mean lifetime in the very first chapter without any mention of half-life whatsoever in its discussion of muon decay as an example experiment for special relativity.

Why would they? Would it have meaning for a muon? Sorry if this appears to be a quiz. It's my long established teaching style. To ask questions rather than to repeat answers.

In both books, the section on nuclear decay mentions both mean lifetime and half-life, but the mean lifetime is introduced first with the half-life written in terms of mean lifetime.

Correct. It should be evident why, don't you see it? Then the half-life can both be defined and described. Defined as a half of something and described as related to something else. It might not be obvious before spending some time in an isotopes lab. And up to now we've covered only two narrow branches of physics, and maybe one of nuclear engineering.

Although the Wikipedia article for damped harmonic oscillators is rather messy and does not really mention either one, the article on RC circuits strictly uses mean lifetime.

I can't find the expression mean lifetime in the RC circuit article. Moreover I wouldn't know the lifetime of what you refer to. Of the circuit? Please, be precise.

I do admit, however, that I have more or less ignored biological applications. Acute toxicity, for example, is often gauged by measuring the amount of poison needed to kill half (on average) of a sample of lab rats.

If you try to refer to the quantity LD-50, how would it relate to half-life or mean lifetime? Am I missing something in your comment?

Unfortunately, that article is still a stub, but general systems of biological halflife (yes, the misspelling is there, and I am in the process of trying to have it moved back to biological half-life) certainly use the notion of half-life.

Yes, it does. It probably lacks (as most other related articles) to clearly state why and when the quantity called half-life is important.

I will try to make the distinction between the physics/engineering mean lifetime and the biology half-life tomorrow morning. Teply 06:55, 11 June 2006 (UTC)

Try to do it after reviewing my comments and questions, so we can avoid further iterations. You might want to try a draft text in this discussion page so we can discuss it before moving it to the article page. And, please, send me scans of your supporting texts. Jclerman 13:11, 11 June 2006 (UTC)