Xref: utzoo talk.politics.misc:8244 sci.misc:980 Path: utzoo!mnetor!uunet!husc6!bloom-beacon!athena.mit.edu!jfc From: jfc@athena.mit.edu (John F Carr) Newsgroups: talk.politics.misc,sci.misc Subject: Re: The Last Word on Friedman, Sevener, and Cuba Message-ID: <3820@bloom-beacon.MIT.EDU> Date: 16 Mar 88 21:20:55 GMT References: <3405@bloom-beacon.MIT.EDU> <3895@whuts.UUCP> <3588@bloom-beacon.MIT.EDU> <3904@whuts.UUCP> <3699@bloom-beacon.MIT.EDU> <3925@whuts.UUCP> Sender: daemon@bloom-beacon.MIT.EDU Reply-To: jfc@athena.mit.edu (John F Carr) Organization: Massachusetts Institute of Technology Lines: 298 Tim: in your inevitable response please make one of the following two statements: 1. You are wrong. 2. EVERYONE else in this newsgroup is a member of a right-wing conspiracy, and therefore you are the only one who has any idea what he is talking about. Else, why hasn't anyone supported you and why have so many said you are wrong? In article <3925@whuts.UUCP> orb@whuts.UUCP (45263-SEVENER,T.J.) writes: >In article <3699@bloom-beacon.MIT.EDU> jfc@athena.mit.edu (John F Carr) writes: :I don't care what your major is - your scientific reasoning is totally :wrong. I will join with the majority in making this accusation of you. :Once again to repeat some major points of this argument so far: : :1)Michael Friedman claimed to "see" Cuba while standing on the : shore on Key West. He claimed to see it, not "see" it. :2)I pointed out that: First, you pointed out that Mike Friedman was lying and it was totally impossible. Since you accuse him of lying rather than being mistaken you must prove that he KNEW he was not seeing Cuba. You have never done this. : a)I, my roommate and others have been to Key West, the shores of Lake : Michigan and other such bodies of water and never been able to see : the opposing shore. So what? This is not proof that it is impossible under all conditions. : I asked if anybody could testify to being at Key West and been able : to see Cuba. : Nobody, outside of Michael Friedman, has personally testified to : being able to see Cuba from Key West. At least two articles mentioned friends who had. : b)I also pointed out that it was *physically impossible* to see : Cuba from Key West, given the curvature of the Earth. : The highest point anywhere close to the 90 mile point from Key : West on Cuba is 344 feet. The height of the tangent line of : sight from Key West to a point 90 miles away is 2059 feet. : I.e. there is a difference of *1700* feet between the tangent : line of sight and the highest point in Cuba close to 90 miles : from Key West. : I asked if there were errors in my calculations. : Nobody has found any yet. : Even John Carr admits they are correct. I say they are correct but not complete. Therefore, they are not the proof you must provide. : c)John Carr, however, claimed that based on his knowledge of refraction : from his Astronomy classes, that the light from the Sun was refracted : 0.5 degrees. Mr. Carr claimed that since the light from Cuba to Key West : was being refracted through sea-level density atmosphere that it : should *also* refract that light by values similar to that for the : Sun and other astronomical objects. I claimed that since the light from Cuba passed through a comparable distance (I assumed, and later proved, that the distance is half as much as sunlight passes through) it would be refracted similarly. : d)I pointed out that this was a totally erroneous view of refraction. : Refraction *only* occurs in a *non*uniform medium or when going from : one uniform medium to another. Exactly. You must have read the article I posted, since this is not your earlier claim. And, it proves my point since air is not a uniform medium (which you finally admitted in your last article). : I provided quotes from Leon N. Cooper's "An Introduction to the : Meaning and Structure of Physics" to back up this point about : refraction. Which quotes were irrelevant and, in one case, wrong (in stating that index of refraction is only defined at an interface between two different materials). : To the extent that a medium such as a gas varies continuously in : one direction, i.e. decreased density as one leaves Earth, then : to that extent it will be continously refracted. True. : On the other hand, to the extent a medium is *uniform*, then light : will not be refracted *one iota*. No. A medium is or is not uniform. Close doesn't count. Air is not uniform, so no further discussion of uniform media is relevant. Also, light in a uniform medium is still bent by gravity (as Einstein and others have proved). (I leave it to the reader to decide if this effect is worth considering). : I further pointed out that the actual difference in atmospheric : pressure between sealevel air and air at 3000 ft is 29.92 inches : vs 26.81 inches according to the Encyclopedia of Atmospheric : Sciences and Astrogeology(p.781-783). : I would argue this is far closer to being a *uniform* medium : than a nonuniform medium. No. NO. no. Ho many ways can I say it? This is the flaw. I proved that the small gradient of the index of refraction is enough, when taken over long distances. Close to uniform doesn't count. : Mr. Carr continues to insult my scientific understanding of : refraction. Or lack thereof. : I would say his argument is not with me but with Leon : Cooper, the authors of the Physics Encyclopedia and other sources : which all give exactly the same view of refraction as something : which only occurs either in shifts of medium or *non*uniform : media. Air is non-uniform. For most purposes the change in density is not important, but it can not be wished away by saying air is uniform. : e)Just to give Mr. Carr's hypothesis the greatest benefit of the : doubt I calculated the distance from the Earth of a tangent line : of 0.5 degrees instead of 1 degree as in my original calculation. : I.e. assuming the *total* refraction Mr. Carr himself states for : the Sun. (actually according to the Physics Encyclopedia the value : is 35 minutes. Only 5 minutes different than 0.5 degrees. For once, : John Carr has something right even if he fails to understand why) : That distance comes out to be 844.8 feet. : A difference of *500* feet from the highest point close to 90 : miles from Key West of 344 feet! : I.e. even *IF* light from Cuba were refracted to the same extent : as light from the Sun (which it is *NOT*!), it is *still* : impossible to see Cuba from Key West. You mean after all this discussion you still assumed the light traveled in a straight line? It doesn't, so your geometric construction is invalid. I included this in my article which you seem not to have read very carefully. : f)Finally, it turns out that the Physics Encyclopedia says that : changes in the index of refraction of a gas are *proportional* : to the density of the gas. This would mean the index of : refraction at 3000 feet can be derived as follows: : : index of refraction at 3000 feet = 1 + (26.81/29.92 * .000293) : : = 1.000263 : : Thus the index of refraction at sea-level is 1.000293 and at 3000 ft : is 1.000263. I.e. .00003 different! : I would call that basically a uniform medium as far as refraction : is concerned! I wouldn't. You just admitted that light is refracted, now you deny it? Remember: I proved the amount by which light is recfracted, you cannot simply say the atmosphere is close to uniform. Do the calculations and you will see. :Here is the way I would evaluate the situation: :1)Michael Friedman was wrong to claim he could see Cuba from Key West. The burden of proof is on you. : It is physically impossible, even with refraction. I have shown it is not impossible under all conditions, which is sufficient defence. : Of course neither Friedman, Carr, Swan, et al are willing to concede : this point, although I have provided references and respected sources : for every step of my argument So have I. The difference is, my calculations and references are relevant. :2)John Carr was wrong to claim refraction from Key West to Cuba is : the same as that from Key West to the Sun because of the distance : the light travels in sea-level density air. I didn't: I claimed it was half this much. I then proved it was. : I was also wrong to make any argument based on similar reasoning : such as my argument that the Sun was further away. : Both arguments have nothing to do with *refraction* which *only occurs* : from a *change* in medium, whether it's a change in gaseous density : or change in substance from air to water, air to glass, air to vacumn, : etc. : Mr. Carr is still unwilling to concede he was wrong on this point. My original statement on this subject was correct. : Instead he insults my scientific understanding even when I have ^^^^^^^^^^^^^^^^^^^^^^^ (I take a short pause to laugh at this.) : posted direct quotes from basic physic textbooks to support my : point. :3)Even if John Carr were right to argue that the index of refraction : between an atmospheric density of 26.81 inches and 29.92 inches : is the same as that between 29.92 inches and 0 inches, he is Which I did not... : *still* wrong in contending that a refraction of 0.5 degrees would : make Cuba visible from Key West. I say again (is there an echo?): light does not travel in straight lines. : In fact, even with a refraction of 0.5 degrees the highest point : in Cuba of 344 feet is still 500 feet below the tangent line : of sight *with refraction*'s height of 844.8 feet. :4)This whole incredibly boring and senseless argument is simply typical ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ I said this first, in the first article to have this subject line. You chose to continue. : of the argument style of Mr. Carr, Mr. Friedman, et al. : When caught flat-out wrong, Mr. Friedman resorted to all manner ^^^^^^^^^^^^^^^^^^^^^^^^^^^ When caught flat-out wrong Tim kept "modifying his position" to avoid admitting his mistakes. When I PROVED he was wrong, he still would not admit it. When others proved him wrong and quoted sources, he continued to hold ideology above the truth. When I cross posted articles from sci.misc, he ignored them. When no one else on the net would associate themselves with his arguments, he claimed a conspiracy against him. : Mr. Carr posted elaborate calculations based on a total misapprehension ^^^^^^^^^^^^^^^ : of what refraction is, and insulted my scientific understanding for ^^^^^^^^^^^^^^^^^^ Please enlighten me then. You seem to have finally agreed to most of my claims. : quoting from an elementary college physics textbook to show he ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Elementary physics courses don't cover continuous refraction. : should know better. : I have provided references to every one of my points. : Let Mr. Carr debate the authors of those references. : To wit: : :References :Rand-McNally World Atlas for highest points in Cuba, radius of :the Earth I have assumed your geographic figures are correct. Judging by your performance quoting other sources it would not surprise me if they were not. :"An Introduction to the Meaning and Structure of Physics" by Leon :N. Cooper for the definition of refraction. I have described how this was irrelevant or wrong (most likely the author understands refraction; but he uses non-standard definitions which fail when Tim tries to extend them beyond the limits of the book.) :Also for meaning of refraction, "New Columbia Encyclopedia", and :"Physics Encyclopedia" : :"Encyclopedia of Atmospheric Sciences and Astrogeology" for :atmospheric density at 3000 ft versus sea-level :"Physics Encyclopedia" for the fact that refractivity of a gas :is proportional to density, for the index of refraction of :1.000293 at sea-level and for the value of 35 minutes for :total refractive displacement of the sun's light on the :horizon These numbers are the same ones I used, within reasonable margins. Have you read the sources which others have quoted? (such as Scientific American) Tim: Don't throw sources at me which do not discuss the specific effect in question. Read the article in which I derived the refraction of a light ray from Cuba. Then repost it showing exactly where I made an error. (hint: there is one mistake in it which does not affect in any way the validity of the calculation, if you had looked at the article carefully you should have caught it. At least one other person pointed it out to me in an email message.) While you are trying to disprove my calculations, you will find it necessary for proof of your claim to also show that there are never temperature inversions in that area (since these would increases refraction). John Carr "No one wants to make a terrible choice jfc@Athena.MIT.EDU On the price of being free"