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Hi, I am a string theorist and a publicist.


Apr
20
revised Is the Mendeleev table explained in quantum mechanics?
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Apr
20
comment Is the Mendeleev table explained in quantum mechanics?
Dear DrSAR, the answer to your question is No, there is no joke or irony, neither intended nor unintended, in my answer. It was a well-defined question whether a subset of physics describes some class of observations and the answer is obviously Yes. I think it's good that this question was asked because people - and not only those who love to visit witches to predict the future etc. - often associate elementary low-energy physics such as atomic physics with lots of mystery that doesn't exist. All these things are almost perfectly understood.
Apr
20
answered Question about SL(2,Z) duality of string theory/N=4 SYM
Apr
20
revised Is the Avogadro's constant equal to one?
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Apr
20
awarded  Nice Answer
Apr
19
awarded  Announcer
Apr
19
comment Is the Avogadro's constant equal to one?
One should study all these things somewhat systematically and controllably but you may review what awaits you e.g. here en.wikipedia.org/wiki/Spacetime and en.wikipedia.org/wiki/Natural_units and en.wikipedia.org/wiki/Special_relativity
Apr
19
comment Is the Avogadro's constant equal to one?
Could you please be more specific about what do I need it for? I surely don't need to use or mention the word, in a written or spoken form, or introduce a symbol for it. I don't need it. Physics doesn't need to talk about the universal constant in the same way as we don't need to add the factor "1" before every letter representing a variable. Again, the cases of $N_A$ and $c$ are isomorphic. In the past, both of them were infinite constants and people didn't know that matter was made of atoms of a specific size; and space and time were unified in a single spacetime that may be Lorentz-rotated.
Apr
19
revised Is the Avogadro's constant equal to one?
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Apr
19
comment Is the Avogadro's constant equal to one?
Yes, in relativity, one may measure time in meters and distances in seconds because relativity shows that time and distance are fundamentally the same quantity, just in different directions. You might measure height in different units than width but because objects may be rotated and standing people may lie in their beds, it makes sense to use the same unit for height and width. The case of time and distance is analogous because the Lorentz transformation - transition from one frame to another - is doing an analogous thing as the rotations; and it induces a conversion between length and time.
Apr
19
revised Is the Avogadro's constant equal to one?
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Apr
19
comment Is the Avogadro's constant equal to one?
Excellent analogy, Mark, +1. ;-)
Apr
19
comment Is the Avogadro's constant equal to one?
Thanks a lot, @David, such a comment from an important member often calms me down. ;-) Dear Bane, $c$ is one because 1 light second is equal to 299,792,458 meters and 1 light second is really the same thing as 1 second. So the "proofs" that they're one in the clever systems of units are fully analogous and they may only be done if one adopts the fundamental equivalence or convertibility of distances and times (relativity, $c=1$), or the fundamental equivalence of the information about the amount and the number of molecules ($N=1$). If one doesn't adopt them, the constants are just not one.
Apr
19
revised Is the Avogadro's constant equal to one?
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Apr
19
revised Is the Avogadro's constant equal to one?
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Apr
19
comment Is the Avogadro's constant equal to one?
Dear @Pygmalion, you live in a misconception. If you happened to read papers on particle physics (or related fields), you would see that almost none of them contains $c$ for the speed of light because $c=1$ in particle physics. There is no inconsistency coming from it - we just eliminate one independent unit, thus simplifying many formulae - and particle physicists are using these units all the time and "think in terms of them". The fact that you're not used to thinking in relativistic terms doesn't mean that there is something wrong about the natural relativistic units with $c=1$.
Apr
19
comment Is the Avogadro's constant equal to one?
Dear @Bane, nope, the situations with $N_A$, $c$, $\hbar$, and others are completely isomorphic to each other. In general systems of units, none of them may be considered to be "one". In a clever system of units, they may be used to convert meters to seconds (or moles to dimensionless numbers of molecules) which means that one may consider these conversion factors to be equal to one.
Apr
19
answered Is the Avogadro's constant equal to one?
Apr
19
comment fitting free QFTs into the Haag-Kastler algebraic formulation
Dear @Urs, citation counts are far from perfect but you would have a much better idea - by many orders of magnitude - about the value of various papers if you meticulously observed them. Surely you don't want to suggest that this Longo-Witten paper is comparable in its importance to Belavin-Polyakov-Zamolodchikov, do you? The LW paper is really maths, not physics. Moreover, the references to AQFT are self-citations to Longo+Rehren so they surely don't carry much information, do they?
Apr
19
comment fitting free QFTs into the Haag-Kastler algebraic formulation
Arnold, the exception you may have been thinking about is Coleman's proof that there are no Goldstone bosons in 2D, projecteuclid.org/…