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The following questions (in no particular order) which I had submitted have been "removed from PSE for reasons of moderation":

  1. Which geometric relations obtain between two distinct rest systems?

Consider, as a thought experiment, a set of participants who measure throughout the experiment having been at rest to each other; among them explicitly participants ${\mathbf A}$, ${\mathbf B}$ and ${\mathbf F}$ who determine the ratios of their (chronogeometric) distances between each other as real number values $\frac{{\mathbf A}{\mathbf B}}{{\mathbf A}{\mathbf F}}$, $\frac{{\mathbf B}{\mathbf F}}{{\mathbf A}{\mathbf F}}$, and $\frac{{\mathbf A}{\mathbf B}}{{\mathbf B}{\mathbf F}} = \frac{{\mathbf A}{\mathbf B}}{{\mathbf A}{\mathbf F}} / \frac{{\mathbf B}{\mathbf F}}{{\mathbf A}{\mathbf F}}$.

Further let there be another set of participants (of which neither ${\mathbf A}$, nor ${\mathbf B}$, nor ${\mathbf F}$ are a member) who measure throughout the experiment having been at rest to each other as well; among them ${\mathbf J}$, ${\mathbf K}$ and ${\mathbf Q}$, who determine the ratios of their (chronogeometric) distances between each other as real number values $\frac{{\mathbf J}{\mathbf K}}{{\mathbf J}{\mathbf Q}}$, $\frac{{\mathbf K}{\mathbf Q}}{{\mathbf J}{\mathbf Q}}$, and $\frac{{\mathbf J}{\mathbf K}}{{\mathbf K}{\mathbf Q}} = \frac{{\mathbf J}{\mathbf K}}{{\mathbf J}{\mathbf Q}} / \frac{{\mathbf K}{\mathbf Q}}{{\mathbf J}{\mathbf Q}}$,

such that

  • ${\mathbf J}$ passed ${\mathbf A}$, then passed ${\mathbf B}$,

  • ${\mathbf A}$ passed ${\mathbf J}$, then passed ${\mathbf K}$,

  • ${\mathbf Q}$ passed ${\mathbf F}$, in coincidence with ${\mathbf Q}$ and ${\mathbf F}$ observing ${\mathbf J}$ and ${\mathbf A}$ having passed each other,

  • ${\mathbf B}$ and ${\mathbf F}$ determined that ${\mathbf B}$'s indication of the passage of ${\mathbf J}$ was simultaneous to ${\mathbf F}$'s indication of the passage of ${\mathbf Q}$, and

  • ${\mathbf K}$ and ${\mathbf Q}$ determined that ${\mathbf K}$'s indication of the passage of ${\mathbf A}$ was simultaneous to ${\mathbf Q}$'s indication of the passage of ${\mathbf F}$.

Question:
Is thereby guaranteed that for these distance ratios obtains

(1)
$\frac{{\mathbf A}{\mathbf B}}{{\mathbf A}{\mathbf F}} = \frac{{\mathbf J}{\mathbf K}}{{\mathbf J}{\mathbf Q}}$ ?,

and (moreover)

(2)
$\left( \left(\frac{{\mathbf B}{\mathbf F}}{{\mathbf A}{\mathbf F}}\right)^2 + 1 - \left(\frac{{\mathbf A}{\mathbf B}}{{\mathbf A}{\mathbf F}}\right)^2 \right) \left( \left(\frac{{\mathbf K}{\mathbf Q}}{{\mathbf J}{\mathbf Q}}\right)^2 + 1 - \left(\frac{{\mathbf J}{\mathbf K}}{{\mathbf J}{\mathbf Q}}\right)^2 \right) = 4 \left( 1 - \left( \frac{{\mathbf A}{\mathbf B}}{{\mathbf A}{\mathbf F}} \right) \left( \frac{{\mathbf J}{\mathbf K}}{{\mathbf J}{\mathbf Q}} \right) \right)$ ?

Or otherwise:
What could be concluded if (1) and/or (2) were not found satisfied?


Aug
25
comment A thought experiment in special relativity theory
@Minimus Heximus: "I think I have to give up. [...] opinions about what'll happen in this experiment. Just a real experiment can be trusted." -- In science it holds, as Bohr put it: "that in each case we must be able to communicate to others what we have done and what we have learned"; and Einstein has provided the necessary means as far as RT is concerned, namely the basic notion ("coincidence") which may be considered sufficiently self-evident and unambiguous. So don't give up on that!
Aug
24
comment Experimental Verification of No Special Frames of Reference
@Nikos M.: "i like the line of reasoning" -- Alright. "but it should also point to experimental tests of SR/GR, as this is what the question asks for [...]" -- Fair enough; this premise shows especially the leading sentence of your question text ("Certainly, there have been numerous tests of both Special Relativity and General Relativity."). So I just added a corresponding remark. p.s. Sorry, I didn't have the chance to respond earlier to your comment.
Aug
24
revised Experimental Verification of No Special Frames of Reference
(v3.1459: some formatting.)
Aug
24
comment A thought experiment in special relativity theory
@Minimus Heximus [Aug 7 at 3:25]: "I deleted my comments." -- Thanks for letting me and everyone know about that. Myself, however, I prefer my comments to stand; including those I had submitted here prior to Aug 7 at 3:25. (Hope this helps.) p.s. Sorry, I didn't have the chance to respond earlier to your comment of Aug 7 [2014] at 3:25
Aug
24
comment A question about special relativity theory
@Minimus Heximus: "in one write the numbers as observer 1 measures and in the other write the numbers a observer 2 measures." -- But how do you propose that any of the directly involved participants listed in my comment above, or all of them, and/or any others should go about measuring any of those supposed "numbers", in order to determine and to express their geometric relations with each other ?? (That's the whole point of RT!, and presumably of your question, too.) p.s. Sorry, I didn't have the chance to respond earlier to your comment of Aug 6 [2014] at 19:17
Aug
24
comment A question about special relativity theory
@Minimus Heximus: "you can draw the picture twice." -- All participants who are directly involved in the setup (ostensibly: the one ("left") "toucher" of "set No 1", the other ("right") "toucher" of "set No 1", the one ("left") "toucher" of "set No 2" the other ("right") "toucher" of "set No 2", the "lamp of set No 1", the "lamp of set No 2"), should be able to understand and agree on their setup relations with each other; provided either of them has the requisit intellectual capability, "like you and me". (Some may find pictures useful to accomplish that.) [to be contd.]
Aug
8
answered Experimental Verification of No Special Frames of Reference
Aug
7
comment Why doesn't the number of space dimensions equal the number of time dimensions?
@Harold: "You could measure time in metres [...] just multiply by c." -- More congruously: Either, referring to SI units, you can express a number of seconds` as the same number of metres, just multiplied by $c/299458792$. Or, referring to quantites: ping duration between two ends (at rest to each other), times $c/2$, is called distance between these ends. On the OP question: If (at least) one identifiable participant took part in several events, we'd call these events pairwise time-like related, and not space-like related. (A basic distinction; some might call it "asymmetry".)
Aug
6
comment Double-slit-experiment but with unobserved alternating opening of slits. Does an interference pattern still arise?
@Sean: "[...] which relates to determining which slit each electron goes through." -- If the "pattern" recorded by the screen is described as "(most probably) due to" source and screen having been separated by a (potential) barrier with "two slits available alternatingly/incoherently" (i.e. the described setup, AFAIU) and only if that pattern consists of two well-separated "blobs", then we can unambiguously attribute all individual entries in the pattern to the corresponding signal "having gone through" either one slit, or the other. Otherwise we can't make that distinction as strictly
Aug
6
comment Double-slit-experiment but with unobserved alternating opening of slits. Does an interference pattern still arise?
@Sean: "There is no large classical device being used [...]" -- Well, it's not explicitly mentioned in the OP description, but there's usually a "screen", or "detector screen" involved; i.e. a device which is suitably persistent (itself, as well as in relation to the signal source) throughout a sufficient number of individual trials to allow recording "a pattern" (based on which the most probable number and "geometry of slits in the barrier between source and screen" throughout the set of trials may be determined). [to be contd.]
Aug
6
comment Question on the logical structure of the EPR argument and Bell's inequalities
user56678: "If, without in any way disturbing a system, we can predict with certainty [...] the value of a physical quantity" -- Just my two cents: I wonder whether there could ever be certainty in predicting that a system under consideration remains "closed" in the next trial. And: "If one measures the spin in the x direction of particle A, one can predict with certainty the spin in x direction of particle B, no matter how far the particles are separated" -- whether a relation (comparison) between "directions" should be called "local".
Aug
6
comment A question about special relativity theory
Minimus H.: "lamp2 will not feel any simultaneous touching." -- Do you perhaps mean that lamp2 will not observe the signals (specificly: the signal fronts) of the event that "the left touchers were touching" and of the event that "the right touchers were touching" in coincidence? If so, I'm unable to draw/follow this conclusion from the given setup description. (And otherwise I don't even understand what you mean at all.) "So it will not light up at all." -- I find analogue circuitry too difficult to draw such a clonclusion. ("It" might light up twice, instead, for instance.)
Aug
6
comment A question about special relativity theory
Minimus Heximus: "Btw, forget these dummy terms and statements and see the main question: For set 1 the touchings are simultaneous while they are not simultaneous for set 2." -- Fine; that's perfectly unambiguous and correct (btw: the correct value of the distance ratio follows as a consequence). "so lamp 1 will turn on but lamp 2 will not." -- I really wonder whether the analogue circuit setup described in your question would guarantee that. (Perhaps, for instance, lamp 1 might flash on once, but lamp 2 might flash on twice? ...)
Aug
6
comment A question about special relativity theory
Minimus H.: ""shorter than what?" than its proper length." -- Fine. Now the converse (as usual when comparing): "The proper lenght of a moving set will become longer/larger than" -- what? Longer/larger than some property of the moving set other than its proper length?? No!, but: Longer/larger than a property of "the other set"; specificly, larger than the distance(s) between pairs of elements (such as the pair of "touchers") of that "other set" whose respective indications of having met/passed ends of the moving set were simultaneous. That's called "length contraction."
Aug
6
comment A question about special relativity theory
Minimus Heximus: "Well this is was SR claims. A moving set will become shorter." -- Not at all. Instead, such statements are what improper presentations of SR make a big fuss about; even though such statements are meaningless and nearly ungrammatical ("shorter" -- than what?; to be determined by which measurement operation?). Anyways, those who understand RT enough to avoid such improper statements and presentations can unambiguously refer to proper quantities; such as for instance the (proper) "mean life $\tau$" of muons".
Aug
6
revised How should two particles accelerate to have their separation Lorentz-contract?
(v3.14159: Having recognized previous versions as improper, trying hard to be more proper henceforth.)
Aug
6
comment A question about special relativity theory
Minimus Heximus: "It means, that ratio for observer 1 is one. For observer 2 it is not one." -- Well, if you meant that "for observer 2 the distance ratio is not equal to $1$", then which value instead? (Perhaps $1 - \beta^2$ ??) Anyways, you seem to mean something improper; pretty much like confusing (misattributing) the distance between two particular railway ties (which were at rest to each other), and the distance between two ends of a "running" train (which were at rest to each other). And that's not helpful in trying to grasp SR.
Aug
5
revised $\frac{1}{\sqrt{2}}$ (|Independent particle Model⟩+ |Strong Interaction Model⟩)?
corrected spelling the name of C. F. v. Weizsäcker; cmp. http://en.wikipedia.org/wiki/Bethe-Weizs%C3%A4cker_formula. Also: cheesed up the title.
Aug
5
suggested suggested edit on $\frac{1}{\sqrt{2}}$ (|Independent particle Model⟩+ |Strong Interaction Model⟩)?
Aug
5
comment What is $c + (-c)$?
I. J. Kennedy: "I'm asking what would happen physically." -- As far as the question concerns only geometric-kinematic relations (and not necessarily "actual emission" etc.) we might simply consider two signal fronts propagating in opposite directions. Of course, the fact (not to say problem) remains that there's no "(inertial) rest frame of a signal front", and hence no "speed with respect to a signal front" defined and to be evaluated. Also related: "Are signal fronts in a beam not at rest to each other?" (PSE/q/104333).