User talk:Mossig

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Hello, Mossig, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Again, welcome! Dunc|☺ 11:31, 6 September 2005 (UTC)

Contents

[edit] Base stations

Hi, could you clarify specifically when adding more base stations does not result in greater irradiation? You mention "Only adds if new channels are added" but I'm not clear what you mean. --- Barrylb 15:13, 25 May 2006 (UTC)

[edit] fdtd simulation of in-vitro exposure setups

Hi Mossig, sorry for the delay in responding... yes, here are some references: [1] [2] [3] [4] [5]. As you see the maximum variation - both as calculated and as measured - using standard containers (Petri dishes or rectangular flasks) is on the order of 3dB. Non-standard container/exposure systems like strip-lines can bring that down to maybe 0.5-1.0dB, but are not used in most studies. Compare that with the AFRL model of a head which has a variation on the order of 36dB, and the variation in whole-organism studies using small lab animals which are on the same order of magnitude, 20-30dB. The point is that if in-vitro studies show an effect at a certain power level, then a whole organism in which any part is at that level can reasonably be expected to have a similar effect in that part, and so looking at the peak voxels in a whole-organism FDTD simulation is correct. ObsidianOrder 02:58, 14 November 2006 (UTC)

Response on talk-page: http://en.wikipedia.org/wiki/Talk:Mobile_phone_radiation_and_health Mossig 15:32, 1 January 2007 (UTC)

[edit] Electromagnetic radiation and health

Hi Mossig - I think that EM Radiation and EMFs are probably close enough in the context of the article -- I think the crucial element in the article is relevance and balance -- thanks for your common sense input on this one, it is appreciated at the moment! Topazg 08:23, 27 June 2007 (UTC)

[edit] re:Damadian article

I have replied on my talk page. Hopefully I didn't create net additional work by my edits! Abecedare 22:19, 15 August 2007 (UTC)

[edit] Tycho Brahe parallax problems

Dear Mossig, Thanks very much indeed for you most interesting information and its sources. However I do not immediately understand the rationale of the repeated observations over a 6 month interval. Certainly if the planets (including the Sun) showed some daily parallax and the supernova always showed less, this would prove it was further away then they were, and showing none whatever would suggest it could be as far away as the fixed stars. But although the maximum daily parallax of the planets changes over time as they orbit the Sun and is at a minimum at conjunction, even 6 months nightly observations would not be enough to establish any daily parallax of the object was even less than this, nor even necessarily relevant, depending upon planetary configurations at that time. Certainly repeated observations on many different nights would be important for establishing the reliability of the eventual concluding relative parallax judgment, but this applies equally to parallax relative to the Moon as to the planets. So what on earth was the significance of the 6 month period of repeated nightly observations to determine whether it was specifically further away than the planets ? Certainly if one wished to determine if it was further away than even the furthest point on the furthermost planetary sphere, and thus beyond the planets, then presumably in that era one would need to establish whether its daily parallax was greater than that of Saturn at solar conjunction. But then a 6 month interval is not an especially required period of nightly repetition of observations to establish the reliability of daily parallax observations, even if Saturn had happened to be at conjunction or thereabouts in 1572. Six months sounds suspiciously like half the solar/terrestrial year when the Earth-Sun relative positions change by 2 AU whether on the geocentric or heliocentric model. But on a circular orbit the Sun's change of position would not change an orbiting planet's minimum daily parallax. I remain baffled.

But the practical point is, if observations over 6 months, or indeed over any other period, were somehow crucially required in respect of changing planetary orbital positions to establish the objects' parallax was always less than that of any planet, then this should surely not be omitted from the text. But since reportedly Tycho found the object never showed any daily parallax whatever, and also given I have no knowledge Tycho ever detected any observable daily parallax for superior planets Jupiter or Saturn at conjunction, I can see no rationale for it. But pro tem I revise the proposed text with the following provisional amendments, which includes the nightly repetition of observations, but is neutral as to whether that repetition was required for any purpose beyond establishing the reliability of observations.

'However, Tycho's repeated observations over several months revealed that the object never showed any daily parallax against the background of the fixed stars within the same night. A terrestrial atmospheric object nearer than the Moon should show a greater daily parallax than the Moon's, which is in the order of 1 degree of arc in six hours. But since it had no daily parallax whatever, not even as much as the Sun that Tycho put at 3 arcminutes nor any of the planets, he concluded the object was so far away as to be in the realm of the daily rotating sphere of the fixed stars.' --80.6.94.131 (talk) 17:16, 28 December 2007 (UTC)

The six month observation period established that the new star had a fixed position relative the sphere of the fixed stars. The parallax claculations had shown that it had to be an object upon one of the largest celestial spheres, ie. either the outer planets or the one of the stars. But Tycho does not draw the definite conclusion of it being on the sphere of the stars from only the parallax calculations, he says that it probably is, but that it also could be on one of the outermost three plants (Mars, Jupiter, Saturnus). Over a period of 6 months the movement of the outermost planetary sphere, the one of Saturnus, is discernable, "even for one, who observed it without the aid of instruments.". (The period of six months seem to be arbitrily chosen as large enough to make the progression of saturnus visible.) And as the only valid alternatives are for the object to be upon one of the celestial spheres, it has to be upon the one of the fixed stars. "Which should be shown", as Tycho writes. But I am not sure if we should include details on this level in the article. Mossig (talk) 23:16, 28 December 2007 (UTC)

Thanks very much indeed for this: will digest ! I too am unsure about appropriate level of detail, but what do you think of what I proposed above ? Maybe add some small phrase to indicate why the 6 month period relevant (once I fully understand it, but interested to see it seems to be for reason I surmised re Saturn but rejected as unlikely)? If you have time, I would also appreciate any feedback you can manage on the further editing proposals I have made in Tycho Talk. --Logicus (talk) 15:56, 29 December 2007 (UTC)

Post digestion: I can make no sense of the logic of Tycho's reasoning as reported above. The proposition that it seems to be trying to justify is:

'Tycho observed Saturn, the furthermost planet, over 6 months to determine whether it always had less daily parallax than Saturn, and was therefore further away, or else that it moved with Saturn and so was in its sphere.'

But the above reasoning seems utterly nonsensical to me for the following reasons.

1) Inasmuch as observations of Saturn were to determine whether it had more daily parallax than the object, then since it is reported the object had no daily parallax whatever, either Saturn showed some parallax and so was nearer, or it showed none and so the object could equally be in the sphere of Saturn, or indeed any other outer planet showing no daily parallax (but which surely excludes Mars on Tycho's Martian parallax observations?). But surely only observations of planets' minimum parallax at conjunction would be relevant, and would have to be zero for the possibility of the object being in their sphere ?

2) Inasmuch as the observations of Saturn were to establish whether or not it moved orbitally with Saturn since daily parallax observations could not decide the issue of relative distance because both Saturn and the object showed no such parallax, then the problem is that observing Saturn is utterly redundant unless the object itself also moves eastward in relation to some fixed stars over monthly time. Only if the object does so move does it become relevant to determine whether its motion coincides with that of any other outer planet also showing no daily parallax. But since as I understand the object did not wander amongst the fixed stars, it could not be a wanderer (i.e. planet) nor a wanderer's companion, so observations of any planetary motions would be entirely irrelevant.

3) The six month period ellegedely required for detecting Saturn's progression is anyway apparently inexplicable. With a roughly 30 year oribital period Saturn covers some 6 degrees of arc in 6 months or 1 degree per month. But this monthly motion amongst the stars should have been well detectable, given the lunar daily parallax was (1 degree in 6 hours).

Further, I offer the following comments on your report inserted in square brackets:

"The six month observation period established that the new star had a fixed position relative the sphere of the fixed stars. [Surely the simple logic here is just that the object did not move against the fixed stars over some lengthy period, and so was not a planet?] The parallax claculations had shown that it had to be an object upon one of the largest celestial spheres, ie. either the outer planets or the one of the stars. [But this conclusion is only valid if these objects, like the supernova, showed no daily parallax.] But Tycho does not draw the definite conclusion of it being on the sphere of the stars from only the parallax calculations, he says that it probably is, but that it also could be on one of the outermost three plants (Mars, Jupiter, Saturnus). [This implies that just as for the supernova, he found no daily parallax for these planets, or at least at their conjunctions.] Over a period of 6 months the movement of the outermost planetary sphere, the one of Saturnus, is discernable, "even for one, who observed it without the aid of instruments.". (The period of six months seem to be arbitrily chosen as large enough to make the progression of saturnus visible.) [At its average rate of orbital progression of 1 degree per month, surely its change of position amongst the stars would be discernible in well less than six months. But this is still not the primary relevant issue, which is surely in the first instance only whether the object itself moved against the stars over some lengthy period, whether the same, more or less than Saturn or not ? And if it did not, planetary observations are irrelevant.] And as the only valid alternatives are for the object to be upon one of the celestial spheres, it has to be upon the one of the fixed stars. "Which should be shown", as Tycho writes. But I am not sure if we should include details on this level in the article."

In conclusion, my provisional hypothesis after considering what may possibly be many red herrings and false hares, is that the simple fact of the matter may well be as follows: Having found no daily parallax, which established it was further away than all planets that do show parallax (at conjunction), but did not establish it was not amongst the outer planets that do not show daily parallax, Tycho then observed the object as nightly as was possible, weather permitting, over as long a period as possible, which just happened to be 6 months for non-astronomical happenstantial reasons, to try and determine whether it moved amongst the stars over time and thus whether it was a planet or a star on the standard reasoning of the time that stars are not wanderers, that is, they do not change their relative positions amongst the other stars because they are immutably fixed in the stellar sphere.

So on this analysis the current text is also crucially misleading in identifying "the world beyond the orbit of the moon [as] that of the fixed stars", since it overlooks the intermediary realm of the planets.

I now propose the current text "Since ...background" be replaced by

'Because it had been maintained since antiquity that the world beyond the Moon's orbit was eternally unchangeable (celestial immutabilty was a fundamental axiom of the Aristotelian world-view), other observers held that the phenomenon was something in the terrestrial sphere below the Moon. However in the first instance Tycho observed that the object showed no diurnal parallax against the background of the fixed stars, implying it was at least further away than the Moon and all those planets that do show such parallax. Moreover he also found the object did not even change its position relative to the fixed stars over several months as all planets did in their periodic orbital motions, even the outer planets for which no diurnal parallax was detectable. This suggested it was not even a planet, but a fixed star in the stellar sphere beyond all the planets.'

NB This requires a weblink to a good explanation of 'diurnal parallax', but which is typically maldefined as caused by a motion of the observer, but which it may not be. Thus Ptolemy observed the lunar daily parallax, but did not conclude the Earth rotates daily, but rather presumed the fixed stars along with the Moon do. Unfortunately the current Wikipedia article on parallax is also typically deficient and misleading in this respect, and requires correction. A simple diagram showing how daily parallax would also arise from a fixed observation position on the surface of a fixed Earth viewing a daily rotating Moon and fixed stars is required. The article is also misleading on stellar parallax, ovelooking simple single object parallax as opposed to dual object parallax.

In provisional conclusion, have I misunderstood your fascinating report of Tycho's deliberations, or have we committed the original sin of Original Reseach in discovering his reasoning was faulty (-:? --Logicus (talk) 15:44, 30 December 2007 (UTC)

[edit] Longomontanus's planetary model etc

Dear Mossig

Do you happen to know whether Longomontanus's 1622 'semi-Tychonic' model had intersecting Martian and Solar orbits or not ? And how many AUs it had for the aphelion and perihelion distances of Mars ?

The history of science literature seems very chary of explaining how the size of the Martian orbit was observationally derived by such as Copernicus, Tycho, Kepler and Co (Wittich, Praetorius, Ursus etc) and why they concluded it was ever less than 2 AU given it had no observable parallax compared with the Sun's assumed 3'. Can you possibly illuminate ?

Also the suggested diagrams are needed for the Ursus and Wittich planetary models to compare with the Tychonic diagrams in their current articles. But I don't know how to incorporate diagrams. Can you possibly help ? --Logicus (talk) 18:55, 28 January 2008 (UTC)

[edit] AIS linkspam

Thanks for keeping an eye on the AIS linkspam.

I'm not sure what to do about this individual; they have been warned repeatedly both here and in the French version of the article. I believe the person is aware that it's against rules but will continue to post the link hoping to increase business to his site (via here, and via google linking his site). The article was anonymous-edit protected for one week, but that wasn't enough. Perhaps we need to request a longer window? What do you think? - Davandron | Talk 03:46, 6 April 2008 (UTC)