Originally posted by Janus
Again, your are trying to make that distinction between "measurement" and "actuality" that Relativity doesn't.
There are a few things going on in our discussion, and some of it seems to have taken us away from the original idea of this thread. I want to try once more to figure this out.
As I’m sure you’ve discerned, you are talking to a non-professional about physics. My objective in study and contemplation is to have a broad understanding about the universe and its contents. Although I did nearly complete a degree in biology 30 years ago, since then I’ve mostly read books intended to popularize science. In one such book
Physics – Concepts and Connections by Art Hobson, he points out the importance of the general population having a solid science understanding because of the “the problems and solutions of our times are bound up with science and its close relative, technology.”
Since we all can’t be scientists, I am grateful for books like Hobson’s. My own specialty is other than science, but I am very interested in and want to understand science fundamentals. You might agree that the best way to get the world on board is for science to be presented in ways everyone can relate to. I guess I am asking for a little flexibility in discussions that involve science. You said, for example, that the “devil is in the details” after I said the details of relativity weren’t that important to the idea behind this thread. I do believe I shouldn’t make any mistakes in my science, but I don’t think it’s important for me understand every element of relativity to set up an essentially non-science hypothetical.
What I think has happened is that you introduced an aspect of relativity beyond my expertise, I was unable to analyze the problem properly, and so we’ve taken off on a separate discussion. Plus, as I will outline below, everything I find appears to contradict at least one thing you
seem to be saying (i.e., I freely admit I may be misinterpreting what you mean). This has made me think about and study relativity for week or so, which has been great for me really because I am grateful to be helped by an expert. You’ve been very patient and attentive, and I thank you for that.
But (you probably knew there was a “but” coming), I can’t see how the “details” of relativity change my little thought problem. In this thread I proposed an idea meant to focus on an aspect of consciousness. If you read my response to Ahrkron, I explained that I’ve become intimate with a part of consciousness which seems immune to the incessant change that goes on in the physical (and mental) world. In an indirect way, I was trying to see if I could interest others in noticing that
constant aspect of consciousness more.
The purpose of my experiment was to ask if the constant consciousness aspect, after having spent 30 years at Earth’s rate of time, would “notice” on his spaceship journey if his physical circumstances had been altered to a different rate of time. I wasn’t suggesting the brain, the intellect, the senses or any other physical factor might notice,
only that constant consciousness aspect. This is the point where you seemed to question the science part of my hypothetical, and it’s why our debate has taken off sideways. How I am interpreting what you seem to be saying is really important if you are correct, because it would mean I am very confused about relativity. Let me explain.
You repeated your objection twice in your last post saying, “The problem you are having is you are trying to distinguish between what is measured from each frame and what is actually happening. Relativity makes no such distinction. . . . Again, you are trying to make that distinction between ‘measurement’ and ‘actuality’ that Relativity doesn't.” However, every physics book I consulted indicated there really is a difference. I called two physics professors at local universities, and they also said there is an “actual” alteration of the time rate in the twins paradox.
Hmmmmm. I am wondering what Janus is saying. I want to understand your point, but I don’t so I pull out a more dedicated physics textbook
Modern Physics by Bernstein, Fishbane and Gasiorowicz. I studied the chapter on the basics of relativity and cannot find a basis for your statement, “. . . you are trying to make that distinction between ‘measurement’ and ‘actuality’ that Relativity doesn't.”
Then in your last post I finally realized you were discussing a prediction for relativity concerning the Doppler shift that I had never heard of. Sure enough, the next chapter in the book I was reading addressed it; in fact, the twin’s paradox was invented by Einstein precisely to talk about the relativistic Doppler shift. In the Bernstein, et seq. book they set up the problem by defining the twins as “harmonic oscillators,” and say that their “ages” are simply a measure of the number of pulses they have emitted. Excellent -- I can relate to this since I see time dilation as due to the altering of cycles. Let me quote part of the book that sets up the problem and then specifically addresses my issue:
“We know by now that in specifying the properties of these oscillators [i.e., the twins] we must be careful to state whether they are in motion with respect to an observer, or whether they are at rest. We shall assume that each oscillator has the proper frequency [the authors mean the formal definition of proper]. . . when it is measured at rest in its own frame of reference. Now we send one of the oscillators – the traveling twin, say, twin B – on its trip. The trip is specified in terms of the rest system of the other oscillator – the stay-at-home twin, or twin A – by the following five sequential steps:
1. The oscillator B accelerates to a speed v in a negligible time.
2. It moves away at this constant speed for a long time.
3. It reverses its direction in a negligible time.
4. It returns to the starting point at the same constant speed v.
5. It stops in a negligible time.
“The stay-at-home twin sees the traveling twin’s clock running slow, by time dilation, and would claim that the traveling twin returns having aged less. But we have emphasized the symmetry of relativistic effects. Why can’t the traveling twin claim that in fact
he is at rest, while the stay-at-home twin is moving? From this point of view, it is the stay-at-home twin who will have aged less. Which one ages less?
This is a question that must have a definite answer, because when the twins get together at the end, they can literally compare their ages. What is wrong with the superficial analysis is that the situations of the twins simply are not symmetric.” [my italics]
The book goes on with an in-depth mathematical analysis that includes allowing the twins to receive pulses from each other so they can calculate how each is aging. After first having the stay-at-home twin calculate his own age based on the pulses, the traveling twin calculates the stay-at-home twin’s age, and then the book states, “This result is identical to the age the stay-at-home twin assigns to himself. The twins have arrived at the same conclusion. The more superficial reasoning at the beginning of the discussion assumed that the two twins were in symmetrical situations. But they are not: One undergoes acceleration and the other does not; there is no symmetry in the situation of the two twins.”
I emphasized the words above with italics because there is exactly what I am talking about. In the twins paradox, the authors point out not only is there an actual aging difference between the twins, but it would be detectable. In your clock tower examples I started looking for situational asymmetry between the clocks to account for the actual difference in aging of the clocks. Even though it has nothing to do with the hypothetical of this thread, it really interests me. Then you seemed to say that one cannot take into account actual aging difference in relativity. Yet every other source I’ve consulted says it is relevant, and so that is where we diverged from the original discussion.
To reiterate, the reason it was important in my hypothetical that an actual change in the rate of time occurred for the traveling twin, is because I set it up that he had had thirty years at Earth’s rate of time. When he traveled, his rate of time was altered from what he was used to. Now although on board ship there would be no indications of that, I was asking, for the reasons I detailed above, if any part of him might nonetheless notice the change. If he really did age slower than he had been used to, that means my hypothetical makes sense. If he doesn’t age differently, then my hypothetical does not make sense. Whether or not you think there is anything within human consciousness that can notice is, of course, another issue.