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There Is No Single Instant In Time
tekkieRich writes "Some interesting news from the world of physics. Supposedly, in this paper, the author answers some of the major paradoxes (achilles vs. the turtle and Zeno) concerning our understanding of time. 'Impressed with the work is Princeton physics great, and collaborator of both Albert Einstein and Richard Feynman, John Wheeler, who said he admired Lynds' "boldness," while noting that it had often been individuals Lynds' age that "had pushed the frontiers of physics forward in the past."'"
when slashcode decided to examine it.
The posting act begins when the submit button is pressed, and ends when the database updates it's article index.
All "events" have a beginning and an end. Some of them have a known duration so the delta is not noted, but it still exists.
I don't know what's so revolutionary about that stance, especially from a practical standpoint, other than maybe the "directionless" nature of time. I think that, however, is an oversimplification that fits into the author's little mental framework he wants to construct. I prefer to think of complex intervals as very small closed sets around the approximate instant. There's nothing wrong or counterintuitive about that.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
OK, I RTFA but i didn't RTFP (paper).
The tortoise vs. Achilles paradox has not really plagued modern physics in that it is not a paradox (anymore - it might have been to the Greeks). The supposed paradox lies in the misconception that an sum with infinite terms will always yield an infinite number. This is obviously not true - As Achilles needs to traverse ever smaller distances he also does that in ever smaller amounts of time.
And the times add nicely up to a finite time - the time when he overtakes the tortoise.
The article claims that this is still a paradox. I think based on the idea in this quote:
> With some thought it should become clear that no matter how small the time
> interval, or how slowly an object moves during that interval, it is still
> in motion and it's position is constantly changing, so it can't have
> a determined relative position at any time, whether during a interval,
> however small, or at an instant. Indeed, if it did, it couldn't be in motion."
Say WHAT?!?
Please tell me why you can't have a well determined position as a function of time and be in motion as well?
He goes on to claim that uncertainties in the values of times is somehow a profound proof that no instant in time exists. Hey, you could say the same thing about the distance the poor fella has to transverse - thus spoiling the whole 'ever smaller distances' thing.
Please enlighten me.
I read about this in the newspaper and thought "wow this sounds exciting". Then I saw the actual paper. It turns out that his ideas are not fleshed out with any mathematics, so its just a philosphical position that he is taking.
I do think that time is a bit of a mystery, and its possible that that his ideas may be roughly right. It might imply that moments or "moment intervals" were some sort of fractal sets, such that a moment can never be finitely splittable (only infinitely splittable). A mathematical model that accomplished this (within the framework of currently accepted/known physics) would be remarkable.
"This seems to me kind of like how you can't just find pi by measuring the circumference or a circle and dividing it by the diameter. I had always thought of this being because there is no such thing as an exact point in space, but maybe I was just misunderstanding or something."
The only reason you can't determine pi to high level of accuracy by measurement is that in practice there will be inaccuracies in your measurements and in the shape of the circle. measurement issue. In principle, given perfect circle-making and measurement techniques, your accuracy is only limited by the Planck length (1.6 x 10-35m).
The Calculus approach is really a summation of an infinite series. Basically that approach breaks the bits of time into infinitely small pieces -- but they are still broken into pieces. The assumption that time can be broken down into an atomic unit is still there. At least, I think that's the gist of what he's saying.
The journal's site is here, though the August (autumn) issue isn't yet available online.
Some significant red flags here. First and most obvious is the wunderkind's lack of training and (presumed) familiarity with established concepts of physics and contemporary research. This isn't a deal-breaker, of course, but it's worth remembering. I'd love to see untrained theorists challenging - successfully - old-guard physicists with some astounding new insights, but I don't think that's happening here.
Wheeler's one-word endorsement - "boldness" - isn't ringing, and the bit about his age (he's 27) is irrelevant.
From a referee: "I have only read the first two sections as it is clear that the author's arguments are based on profound ignorance or misunderstanding of basic analysis and calculus. I'm afraid I am unwilling to waste any time reading further, and recommend terminal rejection." Ouch with a capital 'O'. There's no maths even referred to in this article, either, which I'd like to see.
"Lynds says that the paradoxes arose because people assumed wrongly that objects in motion had determined positions at any instant in time, thus freezing the bodies motion static at that instant and enabling the impossible situation of the paradoxes to be derived." This hasn't really been a problem since quantum indeterminacy.
From a "prominent Oxford mathematician": "A prominent Oxford mathematician commented, "It's as astonishing, as it is unexpected, but he's right." Unnamed source. HUGE red flag.
Within a quote: "Naturally the parameter and boundary of their respective position and magnitude are naturally determinable up to the limits of possible measurement as stated by the general quantum hypothesis and Heisenberg's uncertainty principle, but this indeterminacy in precise value is not a consequence of quantum uncertainty." He gives no alternative explanation for the origins of this 'indeterminacy.' Up to this point the article's summary has proceeded along basic Planck/Heisenberg lines. There's really nothing new here, except the (in this article) unsupported assertion of a new form of indeterminacy that's not related to quantum effects on measurement.
"Lynds continues that the cosmological proposal of imaginary time also isn't compatible with a consistent physical description, both as a consequence of this, and secondly, "because it's the relative order of events that's relevant, not the direction of time itself, as time doesn't go in any direction." Consequently it's meaningless for the order of a sequence of events to be imaginary, or at right angles, relative to another sequence of events. When approached about Lynds' arguments against his theory, Hawking failed to respond." Ignores Feynman's 'arrow of time' characterization of antimatter as equivalent to matter moving in time-opposite fashion. Also ignores simple observation that time does, in fact, appear to move in one direction. In a layman's article it would be good to mention Lynds' explanation for this, if he has one. If he doesn't, well... And Hawking 'refused to respond' to whom? To Lynds? To the author? On what questions? In what timeframe? A phone call during dinner from Australia? Red flag.
"Although Lynds remembers being frustrated with Grigson, and once standing at a blackboard explaining how simple it was and telling him to "hurry up and get it", Lynds says that, unlike some others, Prof. Grigson was still encouraging and would always make time to talk to him, even taking him into the staff cafeteria so they could continue talking physics." Seriously big red flag. 'Hurry up and get it'? Sounds like high school bong-water theorizing.
"Although still controversial, judging by the response it has already received from some of science's leading lights, Lynds' work seems likely to establish him as a groundbreaking figure in respect to increasing our understanding of time in physics. It a
The reason I'm making this post is that I want to point out one thing. Alot of times, when mods, myself included (I metamod about three times a day), come across an article that ranges beyond or above our understanding of a topic, its hard to make a decision as to whether or not something is "informative", like in this article, where I see one post supporting the theory modded informative, and one post criticsing the theory also modded informative. This is physics, people, not YRO. You're either right or wrong in this case. Please do some basic research, please, before modding a post up, just because it sounds intelligent and is well written.
Btw, for all the detractors, this paper was originally published in a European Physics Journal, and most papers submitted to said journals undergo stringent review before being published as fact. This kid is getting supporters in all the right places, and you'll notice that many of his detractors tend to be the type of people who were still arguing the Earth was flat back in the 1800's. Some people just don't want to change, and many of these people are also detractors of Superstring Theory, and are apparently comfortable in dealing with the conflict between quantum mechanics and the theories of general and special relativity.
Another thing I'd like to point out are some of the problems this guy has had getting this paper to light, and receiving the help he deserved from memebers of academia, because of his lack of academic credentials. This is, to a degree, still going on right now. People need to realize that this guy is taking a lot of flak from various experts simply because he doesn't meet their academic pedigree.
Some "experts" need to be reminded that once upon a time someone wrote a very special paper, also widely denounced, also widely refuted for a while. And that person wasn't a department head at a prestigous university, nor was he being funded by wealthy patrons to run his own lab. He worked at a patent office.
Mod Points: Helping you keep your opinion to yourself.
Your post is nonsensical. How can you speak of non-simultaneous observations and at the same time (no pun...) refer to time as a subjective illusion? Are you talking about "the flow of time in one direction"?
There can be no useful distinction between what is "really real" and what models seem to match our sensory data. For example, in string theory you use multi-dimensional membranes where different vibrational harmonics represent different elementary particles. Is this just a practical mathematical model or do these membranes really exist? The question is meaningless. "Das Ding an sich", as postulated by Kant is meaningless.
In quantum mechanics particles and energy can interact over small distances of time (see the Heisenberg uncertainty principle), just as they interact over small distances of space. Also in the theory of relativity time and space are handled almost identically by the equations with the speed of light, c, being just a convertional factor between distances in time and distances in space (almost like converting between meters and feet).
Thus both our best physics models of the world and our subjective understanding of time wants to treat it like a separate real dimension (not a SciFi dimension that you walk through, but a mathematical dimension - a separate orthogonal axis). What further criterions for something "existing" can you have?
The flow of time seems to be purely an illusion though.
Opinions stated are mine and do not reflect those of the Illuminati
Ah, the "academia is really about suppressing the new" conspiracy theory -- the X-Files of the academic world. While there is sometimes an excess of conservatism in "academia", people usually forget how justified caution usually is. For every Einstein-like breakthrough, there are hundreds of crackpot theories. A system is needed to sort through and separate the wheat from the chaff. Oh, wait, we have such a system: peer review and open publication.
This breathless article in EurekAlert has all the hallmarks of a duped science reporter: deep-sounding (but, it seems, semantically null) phrases tossed about with abandon; derision and scorn at the stuffy old guys who just don't get it; and of course the simultaneous disdain for and desparate quoting of authorities. (That is, "most physicists don't agree because they just quote the same old authorities, but look, this Big Name likes my work, which validates it".)
I suppose we'll see how this plays out when the paper is actually published and people get a chance to take a hatchet to it. I'm guessing this will sink like a stone... if it isn't already a hoax.
The Mongrel Dogs Who Teach
then the runner will have to transverse an infinite number of slices to get to his destination, which is impossible
As the other repliers have pointed out, this statement is wrong in the Zeno case. A sum of inifinite series can either converge or diverge. In the Zeno case, the geometric series 1/2^n as n->infinity converges* (thus it doesn't go to infinity to become a paradox in the first place). No fancy new physics is or EVER was necessary to resolve the Zeno paradox, only simple calculus. As with the aether, there is no paradox in the mathematics. The paradox only appears in the (incorrect) human interpretation based on (incorrect) intuition. Galileo said "Without the help of [Mathematics] it is impossible to conceive a single word of it, and without which one wander in vain through a dark labyrinth." *By the ratio test, the limit of the absolute value of Asub(n+1)/Asub(n) is 1/2. Since 1/2 is less than 1, the series converges. See Mathematical Methods in the Physical Sciences, Boas, page 12.