On Mon, Mar 3, 2014 at 3:45 PM, Edgar L. Owen <edgaro...@att.net> wrote:
> Jesse, > > No, it was you that said there was NO correlation. > Jeez Edgar, you really need to work on your reading comprehension. I just got through AGREEING that I had said that there wasn't a correlation, but I explained that this was because I was using "correlation" in the way YOU had consistently been using it up until now, to refer to a 1:1 correlation in which each proper age of a twin is matched up to one unique proper age of the other twin. The archive at http://www.mail-archive.com/everything-list@googlegroups.com/ has a better search function than google's archive (returning individual posts rather than threads), so I searched for posts from Edgar L. Owen with "correlate" or "correlation" in them, results here: http://www.mail-archive.com/search?a=1&l=everything-list%40googlegroups.com&haswords=correlate&from=Edgar+L.+Owen¬words=&subject=&datewithin=1d&date=&order=datenewest&search=Search http://www.mail-archive.com/search?a=1&l=everything-list%40googlegroups.com&haswords=correlation&from=Edgar+L.+Owen¬words=&subject=&datewithin=1d&date=&order=datenewest&search=Search Earliest posts on the "block time" thread I could find in these searches (that were directed at me, and not some other poster) were these from Feb. 12 and 13 (shown in order below), where you can see from the quotes that you were talking specifically about 1:1 correlations that map clock times of one to specific clock times of the other: http://www.mail-archive.com/everything-list%40googlegroups.com/msg48613.html "So all observers are always in the same p-time moment. Now it's just a matter of correlating their clock times to see which clock times occurred in any particular current moment of p-time." http://www.mail-archive.com/everything-list%40googlegroups.com/msg48716.html "Do you see how this mutual agreed on understanding of how each's clock time varies in the other's frame always allows each to correlate their own comoving clock time with the comoving (own) clock time of the other? In other words for A to always know what B's clock time was reading when A's clock time was reading t, and for B to always know what A's clock time was reading when B's clock time was reading t'?" http://www.mail-archive.com/everything-list%40googlegroups.com/msg48750.html "Do you understand that if we have equations for t' in terms of t in A's frame, and t in terms of t' in B's frame, that we can always establish a 1: 1 correlation between t in A's frame and t' in B's frame?" And in subsequent posts I'm pretty sure you always used correlation in the same manner, repeating the phrase "1:1 correlation" many times (you may have gotten this phrase from ghibbsa, who used it in a Feb. 6 post at http://www.mail-archive.com/everything-list%40googlegroups.com/msg48264.htmlthat you quoted in one of your posts that came up in the search results). A similar search for posts by me that use "correlate" or "correlation" doesn't show any posts of mine using these words on the thread prior to your three posts to me above, and subsequently I always used "correlation" in the same sense that YOU had been consistently using it, to refer to a precise 1:1 correlation in ages/proper times. > In any case that's irrelevant if we know you now accept that there is a > very LARGE correlation in most situations, and a definable correlation in > ALL situations. That there is always SOME correlation. > > By actual age changing effect I mean proper accelerations and gravitations > measurable by a comoving scale at specific clock tick events on his proper > clock. There is no doubt these are real actual CAUSES with specific > measurable values that thus must have real actual EFFECTS with specific > actual values. So you are now saying "that all frames DO preserve these > effects"? > What "EFFECTS" do you think they cause? Can you name a SPECIFIC effect on a SPECIFIC variable used in relativity? As I've told you before, if you are talking about some notion of a "change in clock rate", then in relativity there is no frame-independent way to assign a "specific actual value" to the concept of a "clock rate", the clock rate can only be defined relative to a particular coordinate system, so the "clock rate" at a particular event on the clock's worldline can have DIFFERENT values depending on what coordinate system you use. So, if this is in fact what you mean by "effects", then I would DENY that proper accelerations "have real actual EFFECTS with specific actual values". If you mean something else by "real actual EFFECTS", you'll have to name the specific effect or your argument will be hopelessly vague. > > Your 4 point representation of my method MAY BE circular, but my actual > method is NOT circular. > > Your statement 1. is an incorrect statement of my theory. What I assume > FIRST in the symmetric case is NOT simultaneity of ages but simultaneity of > the AGE CHANGING EFFECTS that relativity itself identifies, namely > acceleration and gravitation. > Not clear what you mean by that. Do you mean you ASSUME FROM THE START that if two twins have the same proper acceleration as a function of proper time, then identical values of the proper acceleration are "simultaneous" in some absolute sense? (so for example, if the twins initially accelerate to build up speed in opposite directions, then coast for a while, then accelerate to turn around and eventually reunite, you'd be assuming that the moments that each one began to accelerate to turn around after the coasting phase would be simultaneous in absolute terms) If so this is certainly not assumed in relativity, this would just be a different case of you STARTING with an assumption about absolute simultaneity that you have no rational justification for in terms of any more basic premises, so even another presentist could reasonably disagree with you. > And in the general case the ages are NOT simultaneous nor are the age > changing effects, yet my method still works. Would you claim that in the > NON-symmetric case I start by assuming that NON-identical ages are NOT > simultaneous. No, of course not, so your statement 1. does NOT represent an > assumption my theory makes. > > I've defined this before but here it is again. The frame in which the > accelerations are symmetric is a frame in which the same proper > accelerations of BOTH twins occur at the same proper ages of both twins > "the same proper accelerations of BOTH twins occur at the same proper ages of both twins" is something that is true in ALL frames, so this statement is completely irrelevant to your definition of the frame you are using. > AND in which the proper ages of both twins have the same t value in that > symmetry preserving frame. > There is indeed only one frame where this is true, but you give no rational justification for the idea that this frame's judgments about simultaneity are more valid in absolute or "actual" terms than any other frame's. > They have the same t value because the twins exchanged flight plans and > agreed they would > The fact that they "exchanged flight plans" is also irrelevant, since when they made plans they could just as easily have agreed to use a different frame where identical proper accelerations would NOT have the same t value. So this sentence should be reduced to "They have the same t value because the twins agreed they would", which makes it more obvious that their agreement is merely a matter of settling on the same CONVENTION, not evidence that same proper accelerations having the same t-value is some inviolable absolute truth about reality. > , and we know that their proper clocks MUST run at the same rates under > the same accelerations at the same proper times. > Again, clock "rates" are inherently frame-dependent in relativity, so this is true only if we CHOOSE to use the frame where identical proper accelerations happen at the same t value; according to relativity it would be just as valid physically to choose a different frame where identical proper accelerations do not happen at the same t value, and in this frame their proper clocks would NOT run at the same rates at the same proper times (since clock rates depend only on speed, and they wouldn't have identical speeds at the same proper time in this frame). > Therefore we must choose a frame that reflects that agreed upon symmetry. > "Therefore" is another non sequitur. Nothing is forcing you to choose that frame in relativity, or selecting it out as a more valid representation of "reality" than any other frame; you just find this frame more aesthetically pleasing, that's all. > > > To address your two pair moving relative to each other example if A's > proper time comes out both 0 and 20 at the same point in spacetime that > sounds like a falsification. > > Let me paraphrase it for clarity in terms of a pair of observers A and B, > and another pair C and D. > If you wish. I will translate Alice and Bob to A and B, and Arlene and Bart to B and C. > > If I understand it correctly A and B have the same proper ages, are at > rest with respect to each other but separated in space. > Yes, with the qualification that they have "the same proper ages" according to the definition of simultaneity in their own rest frame, in C and D's rest frame their ages would be different at any given moment. > > And C and D have the same proper ages, are at rest with respect to each > other but also separated in space. > Yes, with the same qualification that they have the "same proper ages" only in their own rest frame, not in A and B's frame. In my numerical example I described all the frame-dependent values using A and B's frame, and in this frame C and D's clock are out-of-sync by 12 years at any given moment (I can show that this follows from the fact that they are synchronized in the C/D rest frame using the Lorentz transformation, if you wish). > > However B and C are initially at the SAME position in space as the pairs > move past each other. > Well, in my example I had Alice and Arlene initially at the same position in space, so I guess this would mean you'd be using B to refer to Alice and A to refer to Bob, which could be slightly confusing when looking back and forth between the examples, but I'm fine with doing it that way. > > A's and B's proper ages are simultaneous in p-time because they are > simultaneous in the A/B rest frame. > > C's and D's proper ages are simultaneous in p-time because they are > simultaneous in the C/D rest frame. > > B's and C's proper ages are simultaneous in p-time because they are at the > same place in spacetime. > Whatever their proper ages AT THAT POINT IN SPACETIME, those two ages are simultaneous. > > NO. for that to be true we have to assume that B's and C's proper ages > were INITIALLY THE SAME AND THERE WAS NO SUBSEQUENT PROPER ACCELERATION OR > GRAVITATIONAL DIFFERENCES. > > > The simple fact that B and C are at the same point in spacetime DOES NOT > require their proper ages to be the same. Obviously not since the twins in > general are at DIFFERENT proper ages when they meet at the same point in > spacetime. How could you believe differently? > Once again you are conflating different possible meanings of vaguely-defined phrases. "B's and C's proper ages are simultaneous in p-time because they are at the same place in spacetime" could mean two very different things: 1. If B's proper age at this point in spacetime in T, then C's proper age at this point in spacetime must be T as well (i.e. their proper ages are "simultaneous" in the sense that they must reach the same age simultaneously). 2. If B and C's worldlines both pass through a specific point in spacetime P, and B's age is T1 when she passes through P, while C's age is T2 when she passes through P, then B must be at age T1 simultaneously with C being at age T2 (i.e. whatever two specific ages they have at P, they must reach those two ages simultaneously, even if the two ages are different) You seem to be using the phrase to mean #1, and arguing against it based on the fact that twins can be different ages when they meet at the same point in spacetime, but I never claimed anything like #1, my own claim is represented by #2. If it helps, I can give the position as a function of coordinate time x(t) AND proper time as a function of coordinate time T(t) for all three observers A, B, C and D in this example (with the understanding that A stands Bob in my original writeup, B stands for Alice, C stands for Arlene and D stands for Bart): For A: x(t) = 25, T(t) = t For B: x(t) = 0, T(t) = t For C: x(t) = 0.8c * t, T(t) = 0.6*t For D: x(t) = [0.8c * t] + 9, T(t) = 0.6*t - 12 Using my statement #2 above, you can verify that "B and C's worldlines both pass through a specific point in spacetime P", namely the point given by x=0 and t=0. At t=0, B is at position x(0) = 0, and C is at position x(0)=0.8c*0 = 0, so this shows that they both pass through x=0, t=0. And it so happens that they both have a proper time T(0) = 0 at this point. However, I have certainly not made a GENERAL RULE that observers at the same point in spacetime must have the same proper time, you can see this just by looking at A and D, whose worldlines both pass through the point x=25, t=20. At this point A has an age T(20)=20, but D has an age T(20)=0.6*20 - 12 = 0. All I am claiming is that since they reach these two different proper times at exactly the same x and t coordinates in the inertial frame I'm using, this is sufficient to show that A's clock reaches a proper time of 20 simultaneously in p-time with D's clock reaching a proper time of 0. Do you disagree? Jesse > > > > > > > > On Monday, March 3, 2014 1:50:40 PM UTC-5, jessem wrote: >> >> >> On Mon, Mar 3, 2014 at 12:36 PM, Edgar L. Owen <edga...@att.net> wrote: >> >> Jesse, >> >> OK, this is some progress. >> >> Now you've gone from saying there is NO correlation at all, to the ages >> ARE CORRELATED WITHIN SOME LIMIT. In other words we DO know that for any >> set of twins we can always say that their ages ARE the same within some >> limits. Correct? >> >> This is a VERY BIG CHANGE in your stated position, from NO correlation at >> all to SOME correlation... >> >> >> Once again your argument turns on vague use of language. You were >> consistently talking about a "1:1 correlation", so naturally I was using >> "correlation" in this sense too. If we say "all inertial frames agree that >> my age T' is simultaneous with my twin's age having some value between T1 >> and T2, but they disagree on the precise value" that is NOT a 1:1 >> correlation, period. So there's been no change in my position, it's you >> whose changing the meaning of "correlation" in mid-argument in an attempt >> to prove me wrong. >> >> >> >> >> You though continue to claim that all frames are equally valid, even if >> they DO NOT preserve the actual age changing acceleration effects between >> the twins, >> >> >> What do you mean by "actual age changing acceleration effect"? If you're >> talking about things that are directly measurable without use of a >> particular frame--like each twin's proper age at any specific event on his >> worldline (including their identical proper ages at the point in spacetime >> where they reunite), or each twin's proper acceleration as a function of >> proper age, then all frames DO preserve these effects. If instead you mean >> the idea that identical ages of separated symmetrically-accelerating twins >> are simultaneous in absolute, non-frame-dependent terms, then YOUR ARGUMENT >> IS TOTALLY CIRCULAR--you are simply assuming from the start that >> symmetrical acceleration implies that identical ages are simultaneous in >> "actual", absolute terms, WITHOUT DERIVING THIS IDEA FROM ANY MORE BASIC >> PREMISES. >> >> >> >> >> while I claim that IF we properly choose a frame that DOES preserve the >> actual age changing acceleration effects that we narrow that limit to zero >> resulting in an EXACT 1:1 age correlation. >> >> >> Yep, that sounds pretty circular all right. As near as I can tell, the >> structure of your argument is this: >> >> 1. Assume without any prior argument that for symmetrically-accelerating >> twins, the "actual" truth about simultaneity is that identical ages are >> simultaneous. >> >> 2. Observe that there is only one frame that "preserves" this "actual" >> truth. >> >> 3. Therefore, only this frame is "valid", other frames are not. >> >> 4. If we use this "valid" frame we can find a unique 1:1 correlation in >> their ages--and that is supposed to demonstrate the validity of premise #1 >> above! >> >> Hopefully you can see that this argument would be completely circular. If >> you think this isn't a fair representation of your own argument, then >> perhaps you can lay your argument out in a step-by-step manner as above, >> with each successive step being obviously derivable from only the previous >> steps. >> >> >> >> <blockquote cla >> ... > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. 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