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06-15-05, 05:05 PM #121Crackpot killer
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Listen, dav57: the theory of relativity depends upon two assumptions, called postulates: the speed of light is constant in all inertial frames, and the laws of physics are the same in all inertial frames.
Originally Posted by dav57
You can derive every conclusion of relativity (time dilation, length contraction, the relativity of simultaneity, and everything else) from only these two postulates. That's how a scientific theory works -- it has assumptions, and provides conclusions. As long as the conclusions are not internally inconsistent, the theory is a "valid" theory. It may not be correct, in the sense that it's predictions (and postulates) may not match reality, but it is valid in the sense that, if the postulates were true, all the conclusions would also necessarily be true.
When I say that you must accept the postulates of relativity to discuss relativity, I am not saying that the postulates of relativity must be correct, or that relativity must describe reality. I'm just saying that if you don't abide by the postulates, you're no longer talking about relativity.
- Warren
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06-15-05, 07:08 PM #122Moderator of B&E forum
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Not necessary the claim that the speed of light is a constant, if physics is the same for all inertial observers.
Originally Posted by chroot
The measure of the vacuum magnetic permability and the dielectric constant of the vacuum in all frames will be the same if physics is the same in all frames. From these two values you can compute the speed of light in vacuum. Maxwell did this years ago. With a little algebra, he derived the "wave equation" from his famous Equations. When this is done, the speed of all electromagnet waves (radio thru gamma rays) is known.
Maxwell not only predicted the existance of these EM waves, which Hertz demonstrated a few years later, but he also gave their speed in air (as the permability and dielectric constant of air differs very little from vacuum).
I think it was Marconii, using an automatic (immediate) rebroad cast (essencially an amplified echo) of a translatic broadcast who first suceeded in measuring the speed of radio waves and thereby demonstrated that, just as Maxwell had predicted, all EM waves travel (in vacuum, no dispersion with frequency) at the speed detemined by the product of the magnetic permability and dielectric constant. Thus, only the statement "Physic is the same for all inertial observers." is required, not two separate statements as you suggest.
Perhaps you should not have banned me from physicforum as this is now the third time I have had to correct you, or perhaps that is why I was banned?Last edited by Billy T; 06-15-05 at 07:27 PM.
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06-15-05, 08:41 PM #123Oh. What happened to a photon which being zero mass has instant (infinite)acceleration to c.
Originally Posted by Lucas
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06-15-05, 09:09 PM #124Crackpot killer
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While this is perhaps true, the reasons are technical. Suffice to say that virtually every primary source on the topic, including Einstein himself, lists two postulates. In any case, it's a triviality in this thread.
Originally Posted by Billy T
No, Billy. You were banned because you continued to talk about "Dark Visitor" as if it were reality, after being told to stop it at least three times by myself and by others on the staff. You chose to continue to break our rules, so we dealt with you exactly as described in the terms of service you accepted during registration.Perhaps you should not have banned me from physicforum as this is now the third time I have had to correct you, or perhaps that is why I was banned?
- Warren
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06-15-05, 09:35 PM #125that was what I was getting at with my post. I was just going to wait for a response to my gedanken experiment.Oh. What happened to a photon which being zero mass has instant (infinite)acceleration to c.
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06-15-05, 09:49 PM #126Have to think
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Originally Posted by MacM
You kiddy, open your lugholes:
A photon cannot have acceleration to c because is always travelling at c (in vacuum) !!!!
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06-15-05, 09:49 PM #127.MacM:
Oh. What happened to a photon which being zero mass has instant (infinite)acceleration to c
Oh. I suppose they are talking about objects that have a REST MASS maybe?
F = ma or a = F/m only applies to ojects with rest mass. They don't accelerate. They are created and can only exist at the speed of light (for any medium). What is this, remedial highschool physics?
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06-15-05, 11:32 PM #128Ah, so when it doesn't exist veloicty is non-existant, hence zero. When it exists it is 'c'. 0--->c Hmmmmm. [deleted]
Originally Posted by Lucas
Last edited by James R; 06-16-05 at 12:40 AM. Reason: personal insults
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06-15-05, 11:35 PM #129What is this a "Play with yourself response?". I didn't say a damn thing about F-ma and particles with rest mass. Do you read english?.
Originally Posted by superluminal
The man said there was no such thing as infinite acceleration. Would you like me to go back and post the number of times I have seen the photon having infinite acceleration written by relativists here?
Get real.
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06-16-05, 12:41 AM #130
Photons don't accelerate. They always travel at c. Nobody has ever said anything different. (Nobody who knows what they're talking about, at least.)
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06-16-05, 02:48 AM #131Extraordinary Thinker Thingy
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You talk a lot of sense and I agree EXACTLY with what you're saying. To have your knowledge and admit that relativity may be based on postulates that may not match reality is something I admire.
Originally Posted by chroot
So, have you ever formed your own set of postulates from which you have attempted to derive consistent conclusions? Or do you rigidly stick to preaching relativity without thinking of possible alternatives? I don't mean that in a derogatory or condescending way.
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06-16-05, 03:06 AM #132Crackpot killer
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Physicists already know we don't know the whole story yet -- we know that general relativity and quantum mechanics are not the final theories. Any physicist will happily tell you that our current theories will undoubtedly be replaced with better ones in the coming years.
Originally Posted by dav57
Well, I don't think I "preach" anything, since I tend to view scientific theories objectively. I'm no more attached to relativity than I am attached to my can opener. As it happens, though, general relativity and quantum mechanics are the best theories that mankind has ever created. They are imperfect and incomplete, but they're the best we've got, and that's why I would prefer to teach them, rather than other theories.So, have you ever formed your own set of postulates from which you have attempted to derive consistent conclusions? Or do you rigidly stick to preaching relativity without thinking of possible alternatives? I don't mean that in a derogatory or condescending way.
Nearly all physicists develop their own theories -- that's what theorists get paid to do, of course. I'm by no means a theorist, but I'd bet that everyone who's ever studied physics in any significant depth has toyed with a few personal theories. I think such personal theories are learning experiences, and are normally cast off like training wheels when it becomes apparent that they are wrong. The simple truth is that vasy majority of the theories advanced by both amateurs and professionals turn out to be wrong, or at least of limited applicability. The theories that have been advanced by amateurs have been, at least so far, almost universally wrong. Science has only existed in its modern form for a few hundred years, however, and it would unwise to say that no amateur could ever contribute meaningfully to the study of physics, but it's spectacularly unlikely at this point in the game.
I will say that the largest distinction between a theorist and a crackpot, aside from education, is that theorists readily attack their own creations, and readily admit defeat when it becomes apparent. In contrast, crackpots are characterised by an unwavering, irrational adherence to their theories, even in the face of direct contrary evidence. Human nature sometimes makes this part of science difficult, but being able to let go is a vital skill.
- Warren
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06-16-05, 03:17 AM #133Extraordinary Thinker Thingy
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Ok, I'm agreeing with you everywhere. Do me a favour, I'm giving Eveneo a hard time with my "ideas" over in the "Question..." thread. Am I on to a loser, in your opinion?
Originally Posted by chroot
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06-16-05, 10:18 AM #134Moderator of B&E forum
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Not "perhaps true - It is true. You were giving the postulates required for SRT. You listed two. In fact only one postulate is required. If I had listed, as a postulate "required" for deriving SRT the fact that inertial mass and gravitional mass are identical, I would be in error, even thought this is true. Likewise you were in error to list "speed of light is a constant" as a required postulate for deriving SRT, even thought that also is a true physical fact. Only one postulate is required.
Originally Posted by chroot
Again you error, and fortunately this is easy to prove, but requires that one examine the archives at www.physicsforum.com. Because many will not bother to do this, I will summarized the history that can be found there and give reference to the posts there, that can be checked to confirm that my version, given below is honest, and yours is false.
Originally Posted by chroot
First, however, let me admit that both here and at physicsforum I have mentioned my book, Dark Visitor several times, perhaps a total of 4 times at each site. I often give reference of various sorts, including to books, witten by others. For example in the Philsolophy section of physicsforum, I have several times referenced the Origins of Consciouness in the breakdown of the bicameral mind and in the Physics threads, Bohm's the Undivided Universe, plus other book references.
I make references to books, including my own, only when something already being discussed in the thread is more fully described in the book. I think it unreasonable to be prohibit from referring to a book that is discussing a thread point (or giving additional evidence directly related to the thread), just because you happen to be the author of it. However, I don't want any reader to think I am trying to profit (sell my book) so I always tell, when ever I mention my own book, how to read it for free. As I do not want to violate this rule, even now: Read Dark Visitor for free at www.iUiverse.com using the "browse feature" available there.
I defy you (Chroot) to site any physicsforum post of mine where Dark Visitor is mentioned and not directly related to the thread or where I fail to tell how to read for free. Please give date of post, thread title and the forum in which the thread appears, because all references to Dark Visitor are months old, now burried deep in the archives. - All reference to it are old because once you had threatened to ban me for citing my own book, like others, I ceased doing so. What I was, in fact, banned for doing occurred months, and many dozens of posts after my last mention of Dark Visitor.
You, both in private messages and publicly, had told me not to make posts about the possible existence, now or in the past, of a small (mass approximately equal to the sun's) black hole relatively close (more than 100AU and less than 500AU) to our solar system. You stated that there were none, never had been one, etc. You still hold this view, without foundation, and may very well be right; however, I have asked you directly, and still do: How do you know this is a "fact"?
You of course have never given any reason why a small black hole could not have passed by the solar system. You just know it never did and could not! I tried to present you with reasons why it might have ocurred, including the very recent reference (2005) www.arxiv.org/astro-ph/0504034
(For thoses who do not know, the "archives of astrophysics" is a very reptuable journal. This particular paper had also passed the review commitee of the conference where it was presented in early 2005.)
On page 6 of that paper, left column, you will find the claim that there may be a very large ("huge"is the term used in the paper) number of small black hole pairs in our galaxy.(I made the word "pairs" bold, because that is precisely the assumption on which Dark Visitor is based.)
This assumption, especially the assignments of dates for the passage, (first and or second decade of the past century and the second member of the pair to be cutting thru the ecliptic in late 2008) are admittedly very very improbable, but violate no known physics. There is even some weak evidence that something unseen did pass by the solar system around 1910+/- ten years. I.e the perturbation of the most distant planet known at that time (Neptune) remains unexplained.
Many astronomers were searching for a more distant "planet X", thought to be the cause of this perturbation. Percival Lowell, was rich, founded the observator that still bears his name at Flagstaff, AZ, and equipted it with newly invented tools (especially the "flicker comparitor" that superposed images of the same star field, which were taken months apart) and a new telescope, especially designed for the search for "Planet X", which we now call Pluto. He predicted, based on these perturbations, but not very accurately, where Pluto would be found.
After Pluto was found, and its orbit was reasonably known, the mass Pluto required to be responsible for the observed perturbations was determined to be several times Earth's mass, and it was believed to be more several times more massive than Earth for two decades. Subsequently, Pluto was determined to be smaller than the moon, but the mystery as to what was the cause of the pertibations,which many observed, has now been forgotten.
What preturbed, Neptune, in the first decades of the last centrury, assuming the perturbations observed by many were not just some form of mass hallucination, is still a mystery. I don't have any strong opinion as to how to explain this historical mystery (from about 1900 till 1930, when Pluto was found). But I can not rule out the posibility that black hole, perhaps passing in the sector of Neptune about 1000AU from the sun could be the explanation. Pluto was in that same sector in the first decades of the past century. It might be possible that the postulated pasage of a black hole was closer to Pluto and thus had some stronger perturbation on Pluto, which was not yet discovered, and contributed to its exceptunal orbit plane tilt.
Again let me note that I have doubts that this patcular explanation is the correct one, but I cetainly think you are on very weak grounds to simple "know it did not happen" without any evidence. (I acknowledge that it is very hard to prove that something did not happen, but you should at least keep an open mind to all posibilities that are consistent with known physics, until the truth is known. To do otherwise, as you do, is unscientific.)
Now I want to sumarize the sequence of posts on 6 May 2005 that got me banned, months after my last mention of Dark Visitor:
Nereid, in the physicsforms forum "General Astronomy & Cosmology" had started a thread: "Massive objects in the immediate solar neighbourhood" some days earlier. That thread was concerned with the possible detection of small black hole near our solar system via their "micro lensing" effect on more distant stars. SpaceTiger pointed out that for BHs close to the solar system, the orbital motion of the Earth would mess up the alignment (Earth/BH/microlensed Star) too quickly for micro lensing measurements, which typically take hours, if not days, to follow the change in the stellar light curve intensity that micro lensing can produce. (BTW, Nereid gives some very interesting references that show samples of these light curve variations. It is worth going to that thread just to get to see these curvers, even if you have no interest in the real reason why I was banned.)
After SpaceTiger's post, pointing out that micro lensing would likely fail to detect a near by BH, I pointed out, in Nereid's thread, that perhaps if the BH was too close to be detected by microlensing, it might be close enought to be detected by what I called a "weak quasar efect." That is a near by BH would be in gas cloud with density slightly greater than the interstellar meduim, because of the solar wind is expanding into the "near by" space. The "swallowing" of this dilute ambient mass might cause the BH to become weakly luminious as dilute solar wind was compressed in the approach to the event horizon of the black hole.
Nereid, responded to my post. He asked me to start a new thread to explore this "weak quasar" detection posibility because he wanted his thread to remain focused on micro lensing. In my post I had asked for help in quantatively evaluating the luminosity to be expected from a "micro quasar". SpaceTiger, who knows more about astrophysics than any three other people I know combined, said that calculation was too difficult for him. So, in the new thread I stared, at Nereid's request, called: "Could a local black hole exists undetected?" I again asked for help, from anyone, to make even an order of magnitude estimate. I used SpaceTiger's data to define "near by" - I.e. to close to the solar system to be detected by micro lensing.
Nereid had asked me "for his thread back" to use his very words, and I of course complied with his request. I suspect, but don't know, that he too was advised not to post "nonsense" about the possibility of a "near by" small BH. I make this guess that he was warned, because despite his asking "for his thread back", he never posted anything there again. That is, my post of 6 May 2005 is still the last post in his thread.
A few hours after I had started my new thread, I discovered I was banned and my new thread had been moved to the graveyard section of "theory development" - a totally ridiculous act as I was asking for help to quantatively analyize a well know physical process, not develop any theory.
Ironically, I was suggesting a possible process that would make it possible to know that Chroot is correct in his currently unfounded belief that near by BH did not occur in the first decades of the past century. That is, I was trying to give an analytic / physical foundation for Chroot's belief, if BHs might have been seen (many were looking) by the "weak quasar effect"!!!!
Unlike Chroot, I have an open mind on this question. - I neither firmly hold that it is, nor that it isn't, possible that a BH could be "near by" the solar system and yet escape detection. I wanted to use physics to evaluate the detecton possibilities, and was banned for even asking for help because Chroot simply KNOWS, without any need for evalution of the related physics, that "It never happened." (Not what I would call an "open mind.")
All the above is easily confirmable by anyone. Just go to www.physicsforum.com Forum "General Astronomy & Cosmology" back many pages in the archives to 6 May 2005. Open Nereid's thread "Massive objects in the immediate solar neighbourhood" and read some of the last posts.
I especially recommend SpaceTiger's quantative demonstration that micro lensing would fail for detection of "Near By" BHs. It is a very impressive, and easily followed, post that established this failure beyond any reasonable doubt. - Very worth reading even if you have no interest in determining the true reason why I was banned. (It is such a valuable post that I have a downloaded copy in my commputer. I can not recommend it too highly.)
Then read my first post in the new thread I started at Nereid's request - Although it has been moved, it is still listed just two below Nereid's and if you click there, you will automaticly be transfered to the graveyard where Chroot burried it when banning me for daring to want to know if small, near by, BHs might (or might not) be detectable.
You will see there is no reference to Dark Visitor in any of these posts. Dark Visitor had nothing to do with me being banned, and had not been mentioned for months. There is one small paragraph (much than the discussion about the perturbation of Neptune presented above!) that does mention the perturbation of Neptune, but only does so in an effort to explain why the detectability of near by small BHs is of historical interest. It is so obviously interesting from a physic point of view (except for people that simply KNOW none could be and never have been "near by") that I did not feel any need to explain why this is an interesting physics question.
Both Nereid's micro lensing and my "weak quasar" detections are perfectly reasonable threads in a serious forum - not a subject to be suppress (as appears to be the case, since Nereid has not used his thread again) nor to ban someone for asking help with a difficult calculation. (If SpaceTiger can't compute it, you know it is a very difficult problem. - I certainly can't. That is why the main body of my new post asks for help, defined the problem, etc. and does not even mention Dark Visitor, but got me banned.)
Check the post that I reference above and see who is telling the true reason for my being banned! All you need do is go to 6May05 forum "General Astronomy & Cosmology" and read some of the posts in Nereid's thread and then my new one.
I appolizize for this post being so long, but I realize that most readers will not bother to check the original posts. However, by making it easy to do so, even if only one does check and finds any reason to dispute the accuracy of the version summarized above, I beg him to reply and tell other readers where I may have made any misrepresentions of what happened that caused Chroot to ban me.
If you do check out the facts and find Chroot's explaination why I was banned is false, but are a participant at physicsforum, I will understand if you make no comment - Why get banned there?
Physicsforum is a good forum, more serious than sciforums, but I have limited time and for me, who likes to teach orthodox physics, and correct errors, such as Chroot's that started this exchange, Sciforum is better use of my time (more things here need correction here). Thus I am actually glad I can no longer post at physicsforum. I.e. Chroot did me a favor by banning me. He should just be honest about the reason - which is: He simply knows that small BHs can't be, and never have been, "near by" and does not want physicsforum "contaminated" by anyone posting that sort of "nonsense." Not even someone only wanting to evaluate the possibility that a near-by BH could exist (or might have in the past) and yet not be detectable, is welcome at physicsforum. Chroot knows the whole subject is nonsense. Period, end of story!Last edited by Billy T; 06-16-05 at 10:55 AM.
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06-16-05, 12:52 PM #135Crackpot killer
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Despite your discontent, it is conventional to list two postulates:
Originally Posted by Billy T
http://en.wikipedia.org/wiki/Special...ity#Postulates
http://nobelprize.org/physics/educat...tulates-1.html
http://www.pa.msu.edu/courses/2000sp...postulate.html
...and so on. If you think I'm so much in error, then you should take your aggression out on the thousands of textbooks and websites which state exactly what I stated. The reasons why only one postulate is strictly required are deep and difficult to understand for someone just starting their education in relativity, so nearly everyone just lists two. Give it up; you don't have an argument, and are just trying to pick a pointless fight with me.
How about some real history?First, however, let me admit that both here and at physicsforum I have mentioned my book, Dark Visitor several times, perhaps a total of 4 times at each site.
You posted 309 times over the course of approximately 2 1/2 months, on a variety of topics.
You personally typed the phrase "Dark Visitor" on physicsforums not four, but 23 times in those 2 1/2 months, approximately once every three days.
You were warned on three separate occassions to stop discussing that topic: 20 March, 12 April, and finally 6 May.
I believe we gave you generous opportunity to align yourself with our terms of service, but you did not.
The last post which contains the word 'visitor' was on 28 April, only eight days before your final banning: http://www.physicsforums.com/showpos...8&postcount=88 This post contained the line "postulated a dark mass of 2.2MSols was now approaching our solar system in a book I wrote."All reference to it are old because once you had threatened to ban me for citing my own book, like others, I ceased doing so. What I was, in fact, banned for doing occurred months, and many dozens of posts after my last mention of Dark Visitor.
Your final post on 6 May included the same material: "a BH may have passed by the solar system in the 1920s": http://www.physicsforums.com/showpos...89&postcount=1
You were banned not only for mentioning your book 23 times, but for continuing to advance a topic which you had been told numerous times was not acceptable on the site. The topic itself was not (and is not) acceptable.
I never said any such thing, but you're missing the entire point: my opinion on the subject is not relevant. Physicsforums is primarily an educational site, and we stick to mainstream, accepted physics -- the sort you'd find in a textbook. It is not the appropriate place to advance questionable theories or discuss what you yourself have called a highly unlikely scenario, particularly not 23 times.You stated that there were none, never had been one, etc. You still hold this view, without foundation, and may very well be right; however, I have asked you directly, and still do: How do you know this is a "fact"?
Again, my personal opinion is not called into question. Your theory is not mainstream science, accepted by a majority of scientists. Therefore, it is not welcome on physicsforums. That's it. Period.Unlike Chroot, I have an open mind on this question. - I neither firmly hold that it is, nor that it isn't, possible that a BH could be "near by" the solar system and yet escape detection.
You used the word "visitor" in reference to a small black hole in the solar system only eight days before you were banned. Give me a break. You didn't put the "dark" in front of it, so we shouldn't have minded?You will see there is no reference to Dark Visitor in any of these posts. Dark Visitor had nothing to do with me being banned, and had not been mentioned for months.
You seem to think I'm some kind of a tyrant with a personal vendetta against you -- that could not be more ridiculous. We have a staff of almost thirty professional scientists, and there was discussion about your theory before any warnings were given, and before the final banning. We do not ban people for talking about our moderation -- that's why we have a feedback forum full of critique. We ban people for breaking our rules, and God help you, you knew exactly what the rules were. We gave you 2 1/2 months and three warnings to help you understand.If you do check out the facts and find Chroot's explaination why I was banned is false, but are a participant at physicsforum, I will understand if you make no comment - Why get banned there?
Should you ever wish to come back to physicsforums, you are welcome -- just leave the non-mainstream science at the door.
Again, my personal opinion is not relevant. It's not mainstream science, so it's not welcome. You never managed to catch on, even after 2 1/2 months, so we showed you the door. Grow up!He should just be honest about the reason - which is: He simply knows that small BHs can't be, and never have been, "near by" and does not want physicsforum "contaminated" by anyone posting that sort of "nonsense." Not even someone only wanting to evaluate the possibility that a near-by BH could exist (or might have in the past) and yet not be detectable, is welcome at physicsforum. Chroot knows the whole subject is nonsense. Period, end of story!
- Warren
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06-16-05, 02:48 PM #136Moderator of B&E forum
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I am not "discontent" and I agree that the constant speed of light is often listed as part of the basis for SRT. The point, however, and it is an important one - (see my recent (about two hours ago) post replying to geistkiesel in thread "Absolute Space....") - is to realize that the assumption/ postulate that "Physics is the same in all inertial frames" is the only "requirement" for the derivation of all of SRT, by mathematics alone
Originally Posted by chroot
To better illustrate why this is important, I now reproduce a little from my recent post to Geistkiesel, in the "absolute space...." thread:
There are here, unfortunately, many people who reject the fact that the velocity of light is a constant. For example, I am currently in a running battle with people who think the speed of light changes as the photons moves thru different gravity fields. I am trying to prove to them that it is only the frequency that changes.
Originally Posted by Billy T
I will respond to the other comments you made very soon in a separate post.
I would like to keep our different views as to why I was banned separate from the physics of what is the required, minium that must be assumed, to derive SRT's results by math alone. I think you now agree with me on this minium requirement. What I am not sure about is if you realize that, as I illustrated to Geisteisel that to reject SRT, one must either (1)reject math or (2)the single postulate that physics is the same in all frames, or (3) reject both.
Thus it is important, if you want to defend SRT, as we both do, not to base it on any more assuptions than are needed. By founding SRT on only math, and the fact that physics is the same for all inertial observers, I can force the people who dispute SRT, MacM included, into this awkward, Draconian, choice between. (1)Dispute math or (2)discard your physics hand books every few weeeks or 3 simply admit to being irrational.
You should be pleased, congratuate me, etc. We are fighting on the same "orthodox physics" team. It is really very ironic that both you and I are fighting the nonsense that is posted in these forums, especially scifroums, but I have been banned.
I do want to complement you on your efforts at physicsforum. It is a much more serious forum. Relatively few post of nonsense (non orthodox physics, invented without any basis, other than wild speculation) exist there, compared to here. And usually when some obvious nonsense does appear, you seem to be right on top of it, kill it etc. (Although I did notice that you permitted many posts in the thread "transformers" to explain the current in the secondary by non existent "flux lines" cutting thru the secondary.)
But in genreral, you do an excellent job of keeping trash out of physicsforum. I congratulate you. You just made a mistake in my case, but eveyone makes mistakes. I must go now, back in about an hour, I think, to respond to the "banning reasons" dispute.
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06-16-05, 04:22 PM #137Registered Senior Member
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The speed of light postulate is not reducible to the relativity postulate. At the time SR was developed there was Newton's mechanics (which is covariant under Galilean transformations) and Maxwell's electrodynamics (which is covariant under Lorentz transformations). If you only take the relativity postulate, you don't know if Maxwell should be modified to conform to Galilean covariance, or if Newton should be modified to conform to Lorentz covariance. Without the speed of light postulate you could go in either direction. With the postulate you are forced to go in the latter direction.
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06-16-05, 04:38 PM #138Registered Senior Member
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Yes but there is still the problem of relativity of simultaneity. The relativity of simultaneity has got to be, without a doubt the most unintuitive of all concepts of physics imaginable.
Originally Posted by Tom2
Now, in another forum I prove the following statement is true:
if the speed of light is the same in all inertial frames, then the lorentz contraction formula is true, and the time dilation formula is true.
The proof of the statement was rather straightfoward.
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06-16-05, 04:47 PM #139Registered Senior Member
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Not at all. There are principles of quantum theory that are far more unintuitive. But unfortunately most of the bozos at this website will never get to that because they can't graduate from relativity.
Originally Posted by Johnny5
Why bother? That proof is in any freshman physics textbook that covers modern physics.Now, in another forum I prove the following statement is true:
if the speed of light is the same in all inertial frames, then the lorentz contraction formula is true, and the time dilation formula is true.
Yes, it certainly is.The proof of the statement was rather straightfoward.
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06-16-05, 05:35 PM #140Moderator of B&E forum
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I don't have the search ability you have as the administrator of physicsforum, so I will accept, your numbers as completely accurate. I had estimated, from memory, not a complete review of my activity there, that in perhaps four posts I had mentioned the book, Dark Visitor (see my last post to learn how to read for free - I alway tell that if book is mentioned by name.) In view of your numbers, I now bet it was about 6, not 4 posts that I mentioned it. My post always tend to be very long. I am in fact supprized that I typed "Dark Visitor" less than 4 times in each post that mentioned it, (assuming there were 6 posts that did. If I mentioned it in only 6 posts out of a total of 309 posts, less than 2% of all my posts, I think I should thank you for proving my main point. Namely that I rarely mentioned my book, and only when it was extremely relivant to the subject of the thread. I hestated to mention it, as no matter, how justfied by the relivance to the thread, there is no way to mention ones own book, without appearing to be a little selfserving/ promotional etc. That is why I made it and still do a policy to always tell how to read it for free, and in many posts tell that it was written as a recuriting tool, to get people not currently interested in physics interested.
Originally Posted by chroot
We had a public exchange in which you complained that if that was my purpose I should not make up an improbable scenario, even if it was physicaly possible. To this argument of yours, I replied, by way of explanation, that I could not just write another, conventional physics book. - there are thousands of good ones already available - because my target reader has no interest in physics, would never open a physics book etc. I had to trick him/her into reading it by not letting him/her know that there would be physics taught in the book. (The first four chapters of Dark Visitor have very little physics in them. They give the family background of the principle characters in the scary story that has the Earth being plunged into a rapid onset ice age beginning in 2009, approximately. (The passage of a "dark visitor" slightly perturbs the Earth's orbit, making it a little more eccentric - but still less than Mars is today. The Earth is very close to an orbit that would make the ice ages that periodically visit Earth, permanent. I again challenge you to find any nonsense/ physics error in Dark Visitor. This basics, improbable, but possible, story is a great vehicle for weaing in a lot of physics into the story, without making it too obvious that I am teaching physics.
Take a look at www.DarkVisitor.com to see a list of the physics I hide in the story, as the astronomer, Jack, explains to his friend what is happening and what will happen, if it is true that the second member of a black hole pair does pass thru the ecliptic at the end of 2008)
Again I assume you are accurate on the first two dates, but 6May was the day I was banned, without warning. Someone did make a post, in the new thread I started at Nereid's request, telling that I did not understand the nature of the perturbtion that lead to the discovery of Pluto but in that new thread, I only mention Neptune and Pluto very briely in one small paragraph of a very long post which was centered on the problem of how to calculate the liminosity of a "weak quasar." The post as I recall, mainly difined the parameter range of a "near by" black hole (SpaceTiger actually did this for me, and I accepted his ideas), discussed the problem, asked for some information about the nature of the solar wind when it was far from Earth and in general invited others to participate and help me make at least and order of magnitude estimate for the "weak quasar" luminosity in the range 100 to 200 AU. I admited there as I do now that this problem is too tough for me to do alone, but I still find it interesting and significant.
Originally Posted by chroot
I now reproduce the entire paragraph in which the "offending word" (visitor) appears:
Originally Posted by chroot
"This is clearly very relivant in a thread called "missing stuff." I would like to have given a direct reference to chapter 8 (Called "dark visitor candidates" in my book) where 5 or 6 different, but consistent with physicis, possible candidites for unseen "missing stuff" are described, but you had so intimidated me that I feared to give a reference to a whole chapter, even though it provides a great deal of information about the subject of the thread, "missing stuff." If anyone else had written my Chapter 8, and I had read their text, I would cetainly have given a reference to it, but as I wrote this text, I dared not be so helpful to the thread.
Originally Posted by Billy T
My post, number 87, made immediately before this one with the offending word "visitor" was also directly related to the thread theme, "missing stuff" but made no referernce to any book, visitor etc, only to a newspaper article. I now reproduce it in its entirety:
First generation (called gen III stars) were among the "missing stuff" discussed in the thread, but as nothing in my book relates to them, it was not mentioned in this post related to gen III stars.
Originally Posted by Billy T
SpaceTiger had, quite early in the thread, provided us all with a list of "missing stuff". In that list were "magnetic monopoles." I do have material on them in my book, specifically in chapter 8, where I suggest both (1)that they would attract each other (a N pole attracting a S pole) strongly over long distances, compared to gravity, which is much weaker than EM forces and (2)might have now all merged into very dense unseen objects (I.e. one of the chapter 8 candidates for a "dark visitor"). This long distance merging could also explain why they are "missing stuff" the standard theory predicts should be there. They are individually very heavy (between 10^16 and 10^23 times more massive than a proton - a hugh mass concentration in only one monopole.- depending on which theoritician's model for the mass you believe.)
Since I do have material on magnetic monopoles in my book, I am somewhat surprized that I did not mention them in the "missing stuff" thread. They were in Spacetiger's list. You must have had me very scared, intimidated. If I did not mention them and yet knew I could give good reference material in Chapter 8 about them. I am ashamed of myself now, for being so scared of your power to ban. It was a duty to the thread to give a good reference, if i could, and I failed.
The point is not did I, or did I not, in less than 2% of my posts at physicsforum mention Dark Visitor. I agree I did in (by your numbers) mention it in about 2% of my 309 posts. The point is did I every mention my book when it was not extremely pertinate to the thread. You can cite every post I made (all 2% of them), but you will not be able to cite even one where I was clearly off the thread subject - I challenge you to use you search facilities as administrator to find such a post.
"I do not deny this. It may be or may not be true. I have an open mind on this possibility. I don't think the many astronomers that were searching for "planet X", the assumed cause of the perturbations of Neptune, (the most distant planet know prior to 1930) were suffering for, mass halliclutions. Every astronomer knows today that Pluto was not the cause ot these pertibations (the first small one being reported before 1910). As far as I am concerned it is an open, interesting, mystery as to the cause. You on the other hand, know it was not a massive invisible object passing well outside of Pluto's orbit. You just "know" and do not permit careful, analysis of this subject at physics form. Just out of curriosity, have you warned Nereid not to post on this subject also?
Originally Posted by chroot
"According to you, that "23 times" is how many times I typed "dark visitor". (less than 2% of all my 309 posts, as best as i can figure out. - I dont have your reaesch tools.) to imply, as you just did that I made 23 posts about it is missleading. I again challenge you to show even one post where it is mentioned and not related to the thread subject.
Originally Posted by chroot
I am not advancing any "questionable theories." I do like to discuss black holes, and try to evaluate, as Nereid was doing in his thread, if they could exist "near by." I have an open mind on this question. Do you? From what you just said, your mind appears to be sealed - shut tighter than any bank vault!
Originally Posted by chroot
I reproduce the entire paragraph above in which the offending word appears. The preceeding work is "space" and the following words are "could be a very old neutron star." Correct me if I am wrong, but I thought neutron stars were an acceptible part of orithodox physics! Give me a break!
Originally Posted by chroot
Thanks for the invitation. I am confused as to what non mainstream theory I am advocating. People here, who have read even five of my posts, must be getting a good laugh at the idea I am non-mainstream. Read a few and judge for yourself. I am very "mainstream," perhaps the most "mainstream" poster here. I am like a hawk watching for non-mainstream posts. When I see one, I swoop down and try to both teach mainstream physics and correct the poster's errors. You have personal experience with this activity of mine, three time. I have even corrected SpaceTiger once, and few can say that. (He did not fully appreciate the role that statistical fluxuations paly in light scatering - I also learn from him in our exchanges and revised some of my statements.)
Originally Posted by chroot
I don't know why you would view me a non-mainstream - the only possibility I can think of is that you have a closed mind when it comes to trying to explore the possible presence, now or in the past, of a "dark visitor" being near by. You just know it is impossible, and always has been.
You have the power to ban, and generally I agree you use it well and physicform is better because of your acts, usually, but in my case you made a mistake. I also challenge you to show any physic related post of mine that is defineitely non-mainstream physics, either here or at physicsform, but don't hold it against me that I have an open mind and know that the mystery of Neptne's pertibations is still unexplained.
I do not think you acted out of spite or personnal grudge against me - just that you made a mistaken call about my "mainstreamness", if I may coin a word.Last edited by Billy T; 06-16-05 at 06:48 PM.

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