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Recently I was told that scientific papers in English use - log_e while French papers use - ln to denote natural logarithms.

The two notations do mean the same. But I was informed that using the notation ln for natural logarithms in scientific papers in English language is inappropriate and I should use only log_e. But I have always been using log for log-base-10 and ln for natural logarithms. (At least this was what I was taught in school)

Do such notations vary from language to language?

I am referring to the publications specific to IEEE, Elsevier etc. related to the Electrical and Electronics field.

Shreedhar
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    They certainly vary from one discipline to another even within a language. Engineers assume "log" is a common (base-10) log whereas mathematicians assume "log" is the natural log. Computer scientists will typically assume it is the binary (base-2) log. Solution? Be clear and consistent. Explicitly state what your notation means. – whuber Jul 12 '17 at 13:27
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    I would keep using $\ln$ – Aksakal Jul 12 '17 at 14:04
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    See [In statistics, should I assume $\log$ to mean $\log_{10}$ or the natural logarithm $\ln$?](https://stats.stackexchange.com/questions/205312/in-statistics-should-i-assume-log-to-mean-log-10-or-the-natural-logarit?rq=1) – Firebug Jul 12 '17 at 19:50
  • @Firebug Yes. I already checked the link that you mentioned. But my question was specific to publications and those related to EEE. (PS: check the last line. To avoid the confusion of duplicate question, I clarified it.) – Shreedhar Jul 19 '17 at 07:57

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There are two meta-principles here.

  1. If in doubt possibly ambiguous notation should be explained. That can be done concisely and just once. Explaining your notation is good scientific and mathematical manners and essential if you want to be easily understood (we won't discuss the opposite case). There are common-sense limits to this. Depending on context and likely readership, you might not need to explain that $\pi$ is the number 3.14159... or even that $\Gamma()$ means the gamma function. Someone who wanted to explain $+$ and $-$ as addition or subtraction would be regarded with puzzlement by reviewers and editors unless they were addressing elementary audiences or trying to be ultra-rigorous about something fundamental.

  2. Individual journals, publishers and/or societies may have a preferred house style, which always takes precedence even when it is ill-advised. If you dislike it, publish elsewhere, or become the Editor and change it.

But what you were told about logarithms (by whom? or where? what reason to respect their views?) seems to me poor advice.

I have been using $\ln$ as one notation for natural logarithms for 50 years and never come across any prejudice that it is not acceptable in written scientific English. According to one common story, $\ln$ notation was invented by an American mathematician! See e.g. this thread on Mathematics SE.

What I have found is a pure mathematical prejudice that logarithms should be written $\log$. That is expressed in Paul Halmos' autobiography, for example. In such circles, $\log$ is regarded as the only notation needed and $\ln$ or $\log_{10}$ as the resort of oily- or muddy-handed scientists and engineers.

Conversely, in a statistical context I would recommend explicit use of $\log_{10}$ if that is what you are using. Loosely, the more statistics you use, the more likely it is that logarithms mean to you natural logarithms, so that $\log$ defaults to meaning natural logarithms. This is largely because any argument based directly or indirectly on differential and integral calculus is immensely cleaner and simpler using natural logarithms $\ln$ or $\log$ as inverse to exponentiation.

The main benefit of $\ln$ is that, assuming only a good high school mathematical background, it is immediately clear what it means.

Nick Cox
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    (+1) "[...] I'd [...] tell my students that the exponential that $2$ is the logarithm of is not $10^2$ but $e^2$; that's how mathematicians use the language. The use of $\ln$ is a textbook vulgarization. Did you ever hear a mathematician speak of the Riemann surface of $\ln z$?" - Halmos (1985), *I Want to be a Mathematician: An Automathography*, Ch.12, p.271. – Scortchi - Reinstate Monica Jul 12 '17 at 15:16
  • @Nick. Thank you for the suggestions. I too am familiar and have been using the same concepts as you said. Currently i'm pursuing my thesis with a French university and they got me confused with it. But I do not blame them as we can see there are so many variations for the same thing depending on the field (mathematics, physics, engg etc.) as said by user[whuber] above. The question, although quite trivial hindered my publication for a week or two. Anyways, thanks again for clarifying. – Shreedhar Jul 13 '17 at 07:55