Re: Definition of Time?
"Paul Murphy" <[EMAIL PROTECTED]> writes: > > September 11-24 , 1752 > Unfortunately, Warren, even this depends where you were at that time! Had > you been in a place where the Gregorian Calendar had been accepted in 1582, > quite a lot might have happened. On the other hand had you been in Russia, > you would have to wait until 1917 to find the lost days!! I wonder something every time I hear about idiot savants who can tell the day of the week of any calendar date. Do they ever make the switch from the Julian to the Gregorian calendar? If so, when? I suspect the psychologists examining them don't know enough about the calendar to realize there is an issue. It's like claiming they can recognize any prime number instantly without asking, say, if the product of two particular ten digits primes is prime. Art Carlson
RE: Help! a novice is knocked down
Hi Fernando, I don't have Waugh, so cannot comment on your main query, but you also ask: PS -- Both Abert Waugh and Rene R. J. Rohr say that in a vertical dial the 12 o'clock line is always vertical. Nevertheless, I've noticed this is not the case for a vertical direct west (or east) dial. Have I found a hint here? [Chris Lusby Taylor] I think you are wrong. A vertical direct east or west dial does not have a 12 o'clock line! At 12 o'clock the sun is in the plane of the dial, so the shadow of the gnomon does not fall on the dial. A very very nearly direct east or west dial does, in principle, have a 12 o'clock line, and it is vertical, passing through the point where the gnomon touches the dial. Unfortunately the gnomon is almost in the plane of the dial, so it protrudes only a very small amount and it is not very practical. This is why direct east and west declining dials are always made with the gnomon held away from the dial. Hope this helps Regards Chris Lusby Taylor
Time
Dear All, I've read the recent postings regarding the nature of time and have been itching to have my two penny worth. Mention has been made of Steven Hawking's book, the jist of which is that time is inextricably linked with space. It was nice to see, therefore, someone's rapid response "Space stops everything happening in the same place" to the posting that "Time stops everything happening together"! Strictly speaking, time only makes sense when considered with space. This makes questions like "What was there before the Big Bang" meaningless! Until the universe was created there was no time!! Slightly off theme (and to draw attention away from the fact that I'm not about to attempt my own definition of time), I read a book containing a number of papers by eminent scientists, one of which was by the physicist Richard Feynman. In it he argued that time need not only go in one direction! Apparently, there seems to be nothing about the physical process that isn't reversable. In a way that's fair enough since if time did change direction for a while, our memories would be undone in the process. It may be that time ebbs and flows and that we are just on a particularly large flow at the moment! And remember, "If we knew for some instant the position and velocity of all the particles in the universe, the rest of time would just be a matter of doing the maths..." David Higgon London
Help! a novice is knocked down
Hello fellows in sundialling I assure you I strived a lot to avoid bringing this problem to you. I can not hide from you the fact that it humilates me. But I still think my ignorance chagrins me more than my failure. So, here I am, humbly asking you to help me one more time with something that should be a child's play... but is knocking me down. Perhaps because I am not a child? Following the instructions found on pages 78-85 of Albert E. Waugh's "Sundials - Their Theory and Construction" I built a N 20 W decliner. It is in place and working fine. Than I went to build the dials for the other faces. Alas! After two weeks of nightly work I am still mystified, completely bewildered with the results I gotten so far. Applying the recipé I found the following: (The algorithm is described pages 78-86.) Data: Phi = 15.7513 Wall: E 20 N The angles I found are: SD (sub-style distance) = -50.4886 (tan SD = sin D * cot Phi) SH (style height) = 64,7434 (sin SH = cos D + cos Phi) DL (difference in longitude) = -53,2830 (cot DL = cot D * sin Phi) AV (6o'clock angle ) = 84.4898 (cot AV = sin D * tan Phi) Converting DL into time units I have 3,5522 = 3 h 33 m 8 s Hour angles from sub-style position are as follows: 1113.76 297.42 380.85 464.55 548.88 634.00 719.80 86.07 Sub-style 97.50 1021.26 1135.52 1250.48 1366.23 1482.58 1599.14 16 115.44 17 131.11 18 145.99 19 160.19 20 173.92 21 187.50 22 201,26 23 215.52 24 230.00 I've calculated the hour for a full 24-hour dial just as a way to double check my calculation. Also, I've done all the number checking that the author recomends. They all indicate the results are good. Nevertheless, when I built the model and put it in place... it does not work. Can somehelp me before I lose my hair? Something must be wrong. But what? What? - fernando PS -- Both Abert Waugh and René R. J. Rohr say that in a vertical dial the 12 o'clock line is always vertical. Nevertheless, I've noticed this is not the case for a vertical direct west (or east) dial. Have I found a hint here? -- Fernando Cabral Padrao iX Sistemas Abertos mailto:[EMAIL PROTECTED] http://www.pix.com.br mailto:[EMAIL PROTECTED] Fone: +55 61 321-2433 Fax: +55 61 225-3082 15º 45' 04.9" S 47º 49' 58.6" W 19º 37' 57.0" S 45º 17' 13.6" W
Re: Definition of Time?
If one is to delve into the question of "What is time?" it may be worth asking the companion question "What is space?" The theory of relativity tells there is a deep connection between the two. And the fact that the spatial question is asked less frequently may imply that it is an even subtler question. Bob Haselby wrote "Without Time, everything would happen at once!" Of course the word "once" depends on the meaning of the word "time." In similar fashion, one could say "Without Space, all things happen on top of each other!" And again the meaning of "on top of" depends on the meaning of space. Finally, if we follow relativity, the real question becomes "What is space-time?" Jim --- -- | Jim Cobb | 540 Arapeen Dr. #100 | [EMAIL PROTECTED] | | Parametric| Salt Lake City, UT | (801)-588-4632 | | Technology Corp. | 84108-1202 | Fax (801)-588-4650 | --- -- I was gratified to be able to answer promptly, and I did. I said I didn't know. -- Mark Twain
Re: Definition of Time?
Hello Art, They would be using the Gregorian Calendar exclusively I believe. Savants solving the weekday problem over a great span primarily make use the fact that a given weekday consistently repeats itself every 28yrs. Freq_1 (7days per weekday) * Freq_2 (4years per 1 day) = 28years per weekday. Of course the number of missed leap days in a given span must also be accounted for. Best Regards, Luke Arthur Carlson wrote: > > I wonder something every time I hear about idiot savants who can tell > the day of the week of any calendar date. Do they ever make the > switch from the Julian to the Gregorian calendar? If so, when? I > suspect the psychologists examining them don't know enough about the > calendar to realize there is an issue. It's like claiming they can > recognize any prime number instantly without asking, say, if the > product of two particular ten digits primes is prime. > > Art Carlson
Re: Definition of Time?
The definition of time is perhaps one of the more interesting conundrums, and one which has engaged me for some time. I find it difficult to come up with a self-originated one, but might recommend two books, which even I as a non-scientist read and enjoyed. One I have recently mentioned on the list, The Calander, by David Ewing Duncan, and the other is, A Brief History of Time, by Stephen Hawkings. They are very different kinds of book, but nonetheless address the question of "What is time?" Duncan looks at time in terms of the world and makind as a practical measure, while Hawking's is a much more scientific look at its meaning in the cosmos. Paul Murphy
Re: Definition of Time?
Unfortunately, Warren, even this depends where you were at that time! Had you been in a place where the Gregorian Calendar had been accepted in 1582, quite a lot might have happened. On the other hand had you been in Russia, you would have to wait until 1917 to find the lost days!! Paul -- > From: Warren Thom <[EMAIL PROTECTED]> > To: Jack Aubert <[EMAIL PROTECTED]> > Cc: Bob Haselby <[EMAIL PROTECTED]>; [EMAIL PROTECTED]; sundial@rrz.uni-koeln.de > Subject: Re: Definition of Time? > Date: 16 October 1998 11:02 > > Dear All, > > If I wished to study history and pick a time when nothing happened, > what diates should I pick? (answer below) > > > > >Thus the time keeps everything from happening at once. > > September 11-24 , 1752 > Warren
Re: Definition of Time?
The philosopher, Bernard Lonergan, has a very astute observation to make about time. He distinguishes between the time that we measure (in minutes, years, etc.) and the time that we experience. Measured time belongs to the data of sense and serves to frame events for an analysis by the natural sciences. Experienced time belongs to the data of consciousness and serves to frame events for analysis by the human sciences. In this latter case, for example, the better historians aim to recreate the sense of things going forward as they were experienced, not as they may be measured. The same goes for the better psychologists -- they don't pay equal attention to every event in your life strung along a time line; they focus on meaningful time, valuable time. I'm relying here on Lonergan's Method in Theology, Chapter 8, "History." Bob Haselby wrote: Achim, My thoughts on time which I,m sure I read somewhere and I often considered as a reasonable sundial inscription is: "Without Time, everything would happen at once!" Thus the time keeps everything from happening at once. Bob Haselby [EMAIL PROTECTED]
Re: Time...
Bruno Stucchi wrote: > >What, then, is time? If no one asks me, I know what it is. >If I wish to explain it to him who asks me, I do not know. > >St. Augustine Confessions, >Book XI, Chapter XIV A Russian emigre with only halting English wished to make sure he would catch his train in London. He stopped a passer by and asked "Plees, vot is time?" "Ah there, my friend, you have raised one of the great imponderables of our existence!" Tony Moss.
Re: Definition of Time?
Dear All, If I wished to study history and pick a time when nothing happened, what diates should I pick? (answer below) > >Thus the time keeps everything from happening at once. September 11-24 , 1752 Warren