geordief

I had in mind 2 lines on a sphere which we draw parallel for a short distance (locally,as I think it is described). When these 2 lines are produced (follow their own direction) they converge.

Are you more of a knowledge for knowledge's sake person or is it more of an itch that needs scratching depending on the particular problem? I think the former kind is an illusion and is related to how knowledge was a more valuable commodity when it was unavailable to others. Even Trump seems to be an expert on aviation these days.

I was thinking that we may be like the scallop with all those eyes around the inside edge of the shell. Each of those eyes (each of us "individually") is the universe peeking out. When we are extinguished we just go back to there whence we came (not the exact same place but the place with the same potential for what we are now experiencing to develop) The wish to "live forever " ,whilst understandable puts the cart before the horse and aims to put our puny individual capacity in charge of the running of the universe itself. Quite apart from the misery or irrelevance such an outcome would actually occasion. Strange is tempted live long enough to see things like quantum gravity understood (if I got that right). That would be a mirage;I am sure there would be many equally interesting questions following on from that.

https://www.solventis.net/products/esters/ethyl-acetate/ Any alcohol,perhaps? What adhesive was that? My nails are shot . Even a little extension might be a nice thing if it was strong ,stable and didn't damage the underlying nail.

Would it be fair to consider Euclidean geometry as a kind of (subset of ) curved geometry in the limit ?(when the local region becomes infinitely small)

Don't they converge on the surface of a sphere? I was thinking of parallel lines as two sets of physical measurements drawn locally where the distance between corresponding opposite elements was constant. If these 2 sets of elements were used to produce 2 lines then ,on the surface of a sphere they would meet and I understand the same would happen in curved spacetime. Since spacetime can be (is?) curved by light itself I imagined that two such lines made of light would eventually converge I think I have learned from this thread that whilst this may be so it is impossible to verify experimentally.

Would gravity be the only force ( if "force" is the correct term) causing light beams to converge? Btw do the two beams generate their own inter attractive force ?(if ,say it was 2 extremely powerful laser beams)

I am no experimenter.Might there be two additional beams of light placed at the extreme edge of the mirrors forming the cavity-?- these to keep a stable distance between them. In the middle would be the two beams whose "parallel effects "we would be interested in. But are you suggesting that the experiment is far too difficult to achieve any worthwhile result? Even one based on statistical probabilities?

Suppose we have an experimental set up where there is a set of mirrors parallel to each other and two beams of light are set off bouncing back and forth in between and perpendicular to them for an extended period. At first the two beams are aligned parallel to each other. Can it be shown that these two beams will always always converge when any effects of gravity are allowed for? If this can or has been experimentally confirmed does it show that there is no such thing in Nature ( the physical world) as the Euclidean idea of parallel lines?(only approximations) Or might there be other ways of attempting to reproduce experimentally Euclidean parallel lines in Nature? Something even more accurate than two beams of light...

Is it the same as form vs content? Does the shape "make" the object?

C Do quantum theories entertain the notion of past and future (whatever about extrapolating)? is it possible to say anything at all about the time ordered nature of any two quantum states (systems?) Are all quantum states(or systems?) "time virgins"?

Is memory the same thing as information? They say that information cannot be lost. Does information imply memory? Is it at all possible to reconstruct any aspect of the earlier state of such a system by observing the emissions? Is information lost in any sense?(maybe "information" has a different definition in this context from my notion of "what we know about something")

Elendirs was saying time required motion and Swansont disputed that. I was tacitly agreeing with Swansont but asking whether the notion of cause and effect we are seemingly familiar with at the macro level was a different beast at the quantum level. If so cause and effect at the macro level might also be fundamentally statistical despite appearances.

I didn't mean set up by human agency but by a chain of cause and effect (in the macro world at least) The sample of radioactive material got there as a consequence of those processes. Does that make sense?

Something" is required to set up the collection of reactions but the individual reactions cannot be shown to exhibit direct )causality as we (= I ,anyway ) would expect. Is that fair? *A region of spontaneous emissions has to be set up at the outset Do you think the idea that the entire world is in relative motion around a stationary observer has any (scientific) merit ? (we don't move at all; everything else does) Does that work simply as a model of little usefulness ? (isn't that idea brought into play with a spinning bucket of water?- not that I understand it) Could that idea have any bearing on what you were talking about(stasis)?

The science of stasis? Or do you mean the shadow?

Does that imply a different kind of cause and effect that what we might expect? If something happens spontaneously does that mean it happened without a direct "cause" ? As if it pulled itself up by its own bootstraps... That seems interesting.You wouldn't care to elaborate at all (I can't see where that idea might go )

If we have a vector that we want to define using a pair of base vectors that do not meet at a 90 degree angle I understand that one way is to combine these basis vectors and, adding a coefficient to each form a parallelogram which has the vector as a "destination". They are contravariant vectors. When it comes to the covariant vectors it seems that we have to follow these contravariant vectors until a perpendicular from them would ,if drawn go through the vector we are trying to describe. The question I want to ask is whether these covariant vectors add in the same way as the contravariant ones. Is is possible to "follow" 2 covariant bases (with appropriate coefficients on each) to ""arrive" at a particular vector or are they used in a different way **such as for example providing an alternative formula for the length of a vector when their coefficient are "spliced into" the contravariant coefficients for the same vector? (the x contravariant coefficient being multiplied by the x covariant coefficient and their sum by added to the product of the y contravariant and covariant coeficients to give an alternative to the squared length of the vector given by the pythagoran theorem in a cartesian system) **I can't seem to construct a parallelogram using covariant vectors with the desired vector at the apex

23 years on potatoes ,apparently. https://www.thesun.co.uk/living/1474652/a-potato-addict-who-lived-on-nothing-but-crisps-for-23-years-overcame-her-obsession-after-doctors-warned-it-could-leave-her-infertile/ Not saying it is the longest (or necessarily true). But it was an interesting story.

Maybe you should remove his/her link in your quote if it is spam?

Does this concept apply? Is there a method of measuring the "distance" (I have a spacetime distance in mind, probably unrealistically) of "individual" observations in any way other than statistically? For example I assume radioactive decay used in timing devices is measured statistically for that purpose. Does it make any sense to attempt to consider two "neighbouring" emissions?

Well what about if 2 massive objects are prevented from approaching one another(=accelerated in a direction away from each other)? They are stationary wrt each other . Is there time dilation between the two objects and is it caused by the continuous movement away from their natural trajectory

When time dilation occurs as a result acceleration is it really caused by the relative motion produced by the acceleration? Or can we have time dilation caused by acceleration when objects are stationary wrt each other? (if such a scenario exists :I have a vague idea it might) There was an initial acceleration going back to the BB. Is that being played out ever since? When you say "the average rate of time in a given locale" do you mean as measured from another frame of reference? You are not referring to proper time in different locales,do you? I am not quite clear what the "ii" I have bolded in your quote refers to....acceleration? "changing co-ordinates" ? motion? -I think you are saying "acceleration is not a reason for time dilation in and of itself"

Each change in the system (each tick) is accompanied** by an acceleration isn't it? All relative motion started with an acceleration at source Don't all changes in any physical system require an acceleration to get things moving? I had a quick look at your example--it requires an initial acceleration to set it up,doesn't it and subsequent oscillations would be derived from that. (hope I am not being obtuse) ** well from your example "accompanied" is wildly overstating it but still is there an association at the outset?

Yes I held that opinion for a long time but no longer. I also understand that time is a property of a system (not a "thing" in itself) but am starting to wonder whether it may be the accelerations in the system which are the salient feature that timing devices show up.(perhaps as an aside acceleration is linked to time dilation just as much as relative motion)