Speed of Time
in [Relativity]
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From: snapdragon31 on 27 Dec 2009 04:42 On Dec 26, 10:04 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 27 Dec, 01:47, Evil's Toy <brani...(a)maksimovic.com> wrote: > > > Ste wrote: > > > I was just wondering, can anyone tell me at what rate time advances on > > > earth? > > > Time does not physically exist. It is mathematical concept to > > describe that something happens. Speed of happening is defined > > by machine called clock, which is based on time needed > > for Earth to make one revolution. > > So we synchronize on Earth revolution and we call that time. > > Oh how believers squirm. > > I am not refuting the measure of time. My position is that it does not > flow ever-forward - and that, for all practical purposes, time is > standing still on Earth. > > But to those who say it *does* move ever-forward, I ask, and what > *rate* does it move ever-forward? Unless you can tell me the rate, > then you have no evidential basis to say it moves ever-forward. > > And let me be clear: if you're a true relativist, you will freely > accept my proposition, that time is standing still on Earth. By the very old definition, a 'day' was the basic unit of time. It was then divided into 24 hours and then divided into 1440 minutes and then 86400 seconds. 'Time flows' is just a way of describing how the time goes one point in time to the other point in time. You are right. Time does not flow but flies (to me). Mathematically, rate of change of displacement = ds/dt = v Rate of change of velocity = dv/dt = a How about the rate of change of time? Rate of change of time = dt/dt = 1 (no unit) The result does not guarantee that the time is moving forward. It only guarantee that when the time is moving forward, the rate is 1 second per second. If the time is moving backward, the rate is also 1 second per second. I cannot give you a more basic proof that time is moving forward. I can only say by normal definition that the flow of time from yesterday to today is forward. From today to yesterday is backward. It is up to you to say whether the time is moving forward or backward. How about the case when the time is standing still? i.e. dt = 0 d?/dt = d? / 0 the result is undefined. That implies the rate of change of anything is meaningless when dt = 0.
From: Inertial on 27 Dec 2009 06:05 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:e47653d2-9f32-440f-a9ac-e16da2296301(a)p8g2000yqb.googlegroups.com... > On 26 Dec, 03:28, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:ee5c4ca0-faf6-46a8-8565-c830f685d3b9(a)m16g2000yqc.googlegroups.com... >> >> > I was just wondering, can anyone tell me at what rate time advances on >> > earth? >> >> There is no such thing as a rate of time, as 'rate' implies change over >> time. That is a problem with the English language (and I suspect most if >> not all human languages). >> >> But one can compare the rates of ticking of clocks (which measures time) >> and >> compare the rates in different locations or at different relative >> velocities. >> >> There is no absolute measure of 'rate' of time (whatever that means) > > Yes, precisely, so *how* do we know it is flowing forwards? That is a very different question > It's a pretty simple question to ask of physics. No .. its not simple at all. A simple answer, though, is that we define 'forwards' as whatever way it is that time 'flows'. > And anyway I think I've just solved the twins paradox to explain why > the astronaut will indeed come back younger. More on that later. Its been explained for a century
From: Inertial on 27 Dec 2009 06:08 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:979171b5-580c-4d86-9a68-fbe6373ad1d8(a)v25g2000yqk.googlegroups.com... > On 26 Dec, 03:31, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:b5e0a622-6862-43ec-9f06-1ae8a46b1d1d(a)k23g2000yqa.googlegroups.com... >> >> >> >> >> >> > On 25 Dec, 20:39, snapdragon31 <snapdrago...(a)gmail.com> wrote: >> >> On Dec 25, 6:21 am, "Dirk Van de moortel" >> >> >> <dirkvandemoor...(a)nospAm.hotmail.com> wrote: >> >> > Ste <ste_ro...(a)hotmail.com> wrote in message >> >> >> > ee5c4ca0-faf6-46a8-8565-c830f685d...(a)m16g2000yqc.googlegroups.com >> >> >> > > I was just wondering, can anyone tell me at what rate time >> >> > > advances >> >> > > on >> >> > > earth? >> >> >> > I suspect you won't like this answer, but every clock tells >> >> > you how its time advances, and the theory that relates one >> >> > clock's time to another clock's, is the theory of relativity. >> >> >> > Dirk Vdm >> >> >> The rate time advances is 1 sec per sec. That is true for all clocks >> >> including those malfunction clocks in relativity. >> >> > Let's do the maths with that then. Time advances at a rate seconds/ >> > seconds (i.e. 1 second for every second). Any number divided by itself >> > is 1. Therefore time advances at 1 second. >> >> it is nonsense to talk of the 'rate' of time >> >> > So I'll ask again, at what *rate* does time advance. >> >> There is only the relative rate at which processes happen >> >> > Telling me that >> > time has a velocity of 1 second per second is as tautologous as saying >> > an object has a spatial velocity of 1 metre per metre. >> >> Indeed it is .. but then, asking the rate of time is similarly >> nonsensical > > I'm only asking the question rhetorically. It wasn't posed rhetorically > My position is that time > does not move *at all*. How can time move? That makes no sense .. as motion is a change over time > It is other people who are saying time flows > forward (which introduces the nonsensical spectre of time standing > still, or flowing backwards). We perceive reality changing in our eternal 'now' and interpret that as time 'flowing forward'.
From: Dirk Van de moortel on 27 Dec 2009 06:18 Ste <ste_rose0(a)hotmail.com> wrote in message ec506642-8744-4fbe-82e0-3937e9e35394(a)m38g2000yqd.googlegroups.com > On 26 Dec, 23:02, "Dirk Van de moortel" > <dirkvandemoor...(a)nospAm.hotmail.com> wrote: >> Ste <ste_ro...(a)hotmail.com> wrote in message >> >> e2b39ba1-e151-4bd3-8adb-b5f35af59...(a)j4g2000yqe.googlegroups.com >> >> >> >> >> >>> On 26 Dec, 09:09, ..@..(Henry Wilson DSc) wrote: >>>> On Sat, 26 Dec 2009 14:28:03 +1100, "Inertial" <relativ...(a)rest.com> wrote: >>>>> "Ste" <ste_ro...(a)hotmail.com> wrote in message >>>>> news:ee5c4ca0-faf6-46a8-8565-c830f685d3b9(a)m16g2000yqc.googlegroups.com... >>>>>> I was just wondering, can anyone tell me at what rate time advances on >>>>>> earth? >> >>>>> There is no such thing as a rate of time, as 'rate' implies change over >>>>> time. That is a problem with the English language (and I suspect most if >>>>> not all human languages). >> >>>>> But one can compare the rates of ticking of clocks (which measures time) and >>>>> compare the rates in different locations or at different relative >>>>> velocities. >> >>>>> There is no absolute measure of 'rate' of time (whatever that means) >> >>>> Time flows at 1 second (t1) per second (t2) >> >>> So in other words, time can only be expressed as a factor relative to >>> some other frame. In other words, it is *impossible* to prove a >>> forward flow of time - the forward flow of time is an axiom of the >>> human mind, not a measurable quality of the physical world. > > Just to clarify, the above text is not mine, even though you attribute > it to me. See http://groups.google.com/group/sci.physics.relativity/msg/3dba684e9f80f45e You did not write that? Which "Ste" wrote it then? Dirk Vdm
From: Inertial on 27 Dec 2009 06:18
"Ste" <ste_rose0(a)hotmail.com> wrote in message news:5b346f59-142c-43de-9543-208e09be2187(a)n35g2000yqm.googlegroups.com... > On 26 Dec, 04:03, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:c6d4ea67-9711-4b79-b35f-7bc54e086b76(a)n35g2000yqm.googlegroups.com... >> >> >> >> >> >> > On 26 Dec, 00:30, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: >> >> >> You should read Dork's twin paradox analysis. He can >> >> pick up the origin of frame of reference and move it, >> >> so if you go from London to New York you can do it >> >> twice without ever going from New York to London. >> >> >> He says >> >> quote/ >> >> "We use 3 inertial reference frames. >> >> S: The frame of the "stay at home" twin. >> >> S': The frame of the "outbound part of the trip". >> >> S": The frame of the "inbound part of the trip". >> >> http://users.telenet.be/vdmoortel/dirk/Physics/TwinsEvents.html >> >> >> So if T = 5 years and v = 0.8c, then the stay at home twin will >> >> have aged 10 years while his travelling twin sister will have aged >> >> 6 years. >> >> /unquote >> >> > I'm afraid I don't understand how he arrives at that conclusion. >> >> He was using the Lorentz transforms of SR > > But the same transformation applied with the astronaut in the fixed > frame of reference (which, according to relativity, is a perfectly > legitimate switch of frame) will yield *the opposite* result. No .. it does not > Clearly > there is something wrong there - Yes .. you do not understand relativity well enough to know how / when to apply the equations > and I think the answer is in good ole > classical mechanics. Nope .. its good ole studying and learning >> > It >> > rubbishes relativity. >> >> Nope > > If the argument is correct it does. It isn't > Of course, really I think the > problem lies in the argument, not in relativity. Yeup >> > Relativity says that both twins will perceive >> > the same effects, relative to their own frame of reference. >> >> No .. it does not. This is something many novices stumble over. The two >> twins are no equivalent as one remains at rest in his initial frame of >> reference, the other twin changes frames of reference (ie does not remain >> at >> rest in his initial frame of reference). > > An absurd position. Not at all .. it is clearly what happens in the scenario. > Of course the astronaut remains at rest in his own > frame of reference. Nope. > It is the *universe* that is accelerating around > the astronaut, according to relativity. Nope .. that's not what it says at all > Believe it or not though, this contrivance of "moving reference > frames" is closer to the truth than you might think. I think I understand it far better than you. > What changes is > not the reference frame. Yes .. it is > What changes is the astronaut's relative > length (i.e. length contraction). Irrelevant in this example > And soon in separate post, I'll tell > you why length contraction is not the same for the homebody as it is > for the astronaut. That should be entertaining >> In fact he changes inertial frames >> three times (given instantaneous acceleration) .. once when he leave his >> twin, one when re turns around to come back, and another when he stops >> when >> he gets back to the stay-at-home-twin. The stay-at-home twin stays at >> rest >> in his inertial frame of reference through out. > > A ludicrous argument, No .. it is how relativity works. Please study it. > that if true rubbishes relativity! No .. it is how relativity works. Please study it. > Relativity > says that an astronaut accelerating through space, is > indistinguishable from space accelerating around the astronaut. Nope > If you > accept relativity, then you cannot deny this. I just did. >> NOTE: You can avoid two of the changes by starting the experiment the >> instance after the twin starts to move away, and finishing the instant >> before he stops .. then there is just one change in inertial frame. >> >> NOTE: You can also eliminate the instantaneous (infinite) acceleration >> altogether by having three 'twins' (triplets then). I'll explain if you >> like. What really makes a difference is the change of inertial frame of >> reference. > > But according to relativity, there has been no change of reference > frame, Wrong > because all reference frames are equal. Nope > There has only been a > change of reference frame relative to the other twin - both will say > the other twin's reference frame changed in the middle of the journey Nope > (one will say the rocket turned around and came back, the other will > say the earth turned around and came back). Nope > If both reference frames > are equal, then we're left with the paradox. If both reference frames > are not equal, then we must discard relativity. Nope .. you really need to understand SR better > The question is, if we retain relativity, then what force or factor > does the astronaut suffer to a greater extent, that the homebody > suffers to a lesser extent? The change in inertial refernece frame. I've already told you >> > If that is >> > true, then the astronaut cannot return younger than the homebody - it >> > cannot happen. >> >> Sorry .. it does > > And therein lies the contradiction. No contradiction > We observe that the astronaut > comes back younger - the observation cannot be denied. Yeup > We must > therefore deny the coherence of the explanation. It is perfectly coherent >> > Because if you change the analysis and have the >> > astronaut in the fixed frame of reference, and have the universe >> > accelerate around him, then by exactly the same logic the *homebody* >> > will be the younger twin when the astronaut returns to earth. >> >> Nope .. you can do the analysis from either point of view, and you get >> the >> same result > > That is not possible. Yet it is the case. Clearly your idea of what is impossible is wrong > You cannot possibly do an analysis that involves > the earth accelerating away from the astronaut, Because the earth never accelerates away from the astronaut. It is only the astronaut that experiences acceleration > and still have the > astronaut come back younger, because by your own argument the *earth* > has changed reference frames at the turnaround, No .. it has now .. I never argued that .. nor does SR > and the astronaut's > reference frame has remained constant. Wrong > Clearly, this "changing reference frame" business is a gratuitous > failure to grasp relativity. The one failing to grasp here is you. Go study >> > If the astronaut is younger when he returns, then either relativity is >> > false, or there is another factor in play that applies differently to >> > the astronaut than the homebody. >> >> > Incidentally, what evidence is there exactly to suggest that such >> > twins ages would differ once the astronaut returned to earth? >> >> Because less time has elapsed for the travelling twin. > > In other words, my question is "why is the twin younger", and your > answer is "because the twin has aged less". Thankyou for that dynamite > response. It is due to the change in simultaneity > I was actually looking for you to name studies that have proven the > effect. There have been several experiments sowing time dilation etc > I presume astronauts themselves have not come back discernibly > any younger than their earth-bound families. Such experiments have been performed .. it is known fact >> Unlike spatial dimensions, where the shortest distance between two point >> is >> a straight line (and so a twisty path is longer) for the temporal >> dimension >> the straight line is the longest temporal distance (elapsed time). The >> more >> you move in your path from one event to another, the shorter the time >> taken. > > Naturally. If you think that is somehow intuitive, then you probably don't understand > If I travel at 10mph, 1 mile of distance takes 6 minutes to > cover. If I travel at 60mph, 1 mile of distance takes 1 minute to > cover. As expected .. you do not understand . Do you even know what 'event' means? > That does not explain why, when I come back from my journey, I > will be any younger than my housebound family. I don't think you understand enough of the fundamentals of SR yet to understand the explanation |