Time dilation

[josh]

Is that how you spell it ?
I just read about a hipothetical space ship taking a round trip to a star 100 light years away. They are traveling a fraction under the speed of light. It said that those on board would age 2 years but 200 years would pass on earth. Everyone they knew would be dead when they got back. I just have alittle trouble understanding the hows of it . Can anyone help?
Thanks for any smarts you can all share.

[josh]

Check out my question in general chat. Its very, very important. If we can come to a firm decision i feel it will change the world we live in for the better!

[ving]

nice post count josh ;)

while i understand how it all works explaining it is another matter... one that is boeyond me. but some bright spark will bwe able to do it :)

[davidpretorius]

ok, here's my spin on it,

travelling at the near the speed of light and even higher in the earths gravity will mean that time will "tick" away at a different rate. This has been proven scietifically by flying an atomic clock up up in a plane and then comparing it to a synchronized gound based one.

So, on the trip out to the stars at a CONSTANT speed, time will be different for the astronauts that the earth based guys. I can't remember who will be older though.

Now the problem is that special relativity does not allow for acceleration, and so the problem happens when you get to the star and decelerate to turn around and then accelarate to come back. This from memory is where all the comparative aging occurs

I will grab my special relativity book and quote from it tonight

[robagar]

yep, according to special relativity a moving clock appears to go slow. So from the point of view of the people on Earth, the spaceship clock ticks slowly and passengers age more slowly than themselves. But the odd thing is this: from the point of view of the the passengers, the clocks on Earth are the ones moving and running slow! (this is known as the Twin Paradox btw)

As David says, it's the acceleration that takes it out of SR's domain and breaks the symmetry between Earth and the spaceship people, so it the passengers who stay young.

[fremanwarrior]

This has levered a fantastic memory from my child-hood. This was in fact one of the very first really cool fact things I can remember discovering for myself. If my memory is correct I read about this off a super cool (well I remember it as super cool) SPACE 1999 wall poster!

http://www.space1999.net/~catacombs/cybermuseum/index.html

[drmorbius]

Hey Josh...

If that kind of stuff interests you, then I heartily recommend the book "The Elegant Universe" by Brian Green.

It is a laymans desciption of Superstring theory, which covers Einsteins' General and Special Theories of Relativity AND Quantum Mechanics. It's a very complicated subject, but he does a pretty good job explaining it all.

And the concept of time slowing down as you approach the speed of light is nothing compared to what gravity REALLY is.... and the theory that the fabric of the universe has 11 dimensions. I loved it! :thumbsup:

BTW - Green also did a series that was shown on SBS... you can get the DVD at some bookstores.

[robagar]

yeah Brian Green's The Fabric of the Cosmos is a good 'un too. As it says on the back cover - "the new Hawking, but better" :D

[drmorbius]

Nice title robagar... :lol:

If you don't understand his Calabi-Yau reference... you have to read the books! :D

[robagar]

thanks doc! :D I was beginning to think it was perhaps a smidgen too nerdy :eyepop:

[josh]

Thanks randall, ill give it a try.
Its good to hear your takes on it. Its a difficult topic to grasp. Brings up all sorts of question about time/reality and what it really is.... if anything.
I think i need a good book and lots of time (no pun}

[AGarvin]

Special Relativity does most folks heads when they first suss it out. Time dilation is derived through what are known as the Lorentz Transformations. Conceptually it's not that hard to understand once properly explained, just difficult to explain on a message board. A few simple diagrams can make it much easier. I'll give it crack though.

Basically, it centres around the fact that the speed of light is the same for all observers. The stationary observer will see the light travel further than the person in the ship will for the same event. If the distance is further, but the velocity is the same, then the time taken must be 'longer', or dilated.

Imagine the person in the ship, we'll call him the spaceman, is holding a mirror up to his face, and our event is a beam of light travelling from his face to the mirror, a distance of d. According to our spaceman, the light ONLY travels from his face to the mirror, distance d.

Now the 'stationary' observer sees it slightly differently. Since the spaceman is moving with uniform velocity, our spaceman has moved, according to this observer, between the time the light leaves the spacemans face and the time it reaches the mirror, a distance of d2. So according to the stationary observer, the light has actually travelled d + d2. Even though he's seeing the light travel further, the velocity of light is the same for both of them.

Using insanely oversimplistic math, (not to mention non relativistic), and plugging in a few nice round figures to illustrate the point, you have: t = d/v (t=time, d=distance, v=velocity)

According to spaceman, d=200, v=100, so time=2 (200/100).
According to observer, d=400 (d+d2), v still = 100, so time=4 (400/100).

In a classical, or non relativistic sense, the velocity of light according to the observer would be increased by the velocity of the spaceman, so even though it travels further, it would do it with a higher velocity, so time integrity would be maintained. Not so with light. All observers record it as having the same velocity. So according to our spaceman, it took 2 time units for the light to go from his face to mirror, but according to the observer, it took 4.

For the purists, the actual Lorentz formula is:

t0 = t1/sqrt(1-(v/c)^2)

where t0 is time in your reference frame lasting t1 seconds in a frame moving at v.

Hope I havent rambled on to much (and all of this makes sense).

Cheers,
Andrew.

[josh]

Thanks Andrew.
It seems the harder i look , the more questions appear. I was never that good with maths so its pretty hard for me to grasp, but it think im getting there.
Ill go away and think, and if my mind is still working ill come back with some more questions.
Here goes:doh:

[xelasnave]

Andrew if you are still there???
Is the effect observational or real in your view? I imagine yet another observer "standing" elsewhere may see things differently?
alex

[AGarvin]

Hi Alex,

As far as I know it's very real and very observable and has been proved using such tools as satellites and atomic clocks, and I think more recently by somehow measuring lasers via spectroscopy. Don't ask me about the actual experiments though as I don't know much about the details. I'm guessing there's been a number of experiments over the years.

And yep, each observer will see things relative to his frame of reference.

Cheers,
Andrew.

[xelasnave]

I have been trying to find something but I will go on without it. Does not the time remain the same but because of the speed of light each will "see it" differently...and yet another observer will see the times as different again... but in the real world has anything changed? I think the atomic clock observations are dubious. As you say you are not sure about the experiments, neither am I but I have not been able to find anything conclusive.
alex

[Starcrazzy]

Hey giys..time dilation is there alright and a very real consequance of the c constant...If you imagine a guy bouncing a ball up and down on a train, according to him the ball is travelling down to the florr and bouncing back up to his hand , all this takes a certain amount of TIME..and the ball has traveld a certain distance say 2 meters..now...an observer standing on the side of the track and looking through the glass wall (hehe) would see something completely different...( i forgot to mention the train is going along at 100 km/h) he sees the ball travell forward around 10 meters, hit the floor and rise up and travel forward another 10 meters as is goes back into the blokes hand...now...the two observers agree on the TIME it has taken, but not the distance...and seeing as the SPEED is distance over time, they can not agree on its speed, and the kicker is, neither has a privaliged point of view...while the train is travelling at a constant speed the ball still obeys all the laws of motion(on the train) .....there ya have it...time dilation on a train...lol...its a real and measurable quantity, they teach it to year 12 physics students and test there use of the formula...The effects are also quantised for the use of gps sateelites and so-on, they require an absolutely accurate measure of time to give realiable readings and have a dilation factor built into them becasue of there speed...hawking alex...you NEED him in your life...if you pm me your adress ill send you a couple of his books....

[ballaratdragons]

OK, you are all talking about a Spaceman leaving Earth and travelling at the speed of light and does he age or slow his own time compared with Earthbound folk.

What if the scenario was reversed. A spaceman coming from a distant star system at the speed of light! Is he coming from our future but his normal time or from the VERY distant past just like starlight?

I love throwing spanners into the works, but try sort that one out.

[xelasnave]

I have read a fair bit of Hawking its just that I dont see things the way others see things I guess. A mental impass or a belief that there is something not quiet right. That makes me a laughing stock but that is of little concern.
The guy on the train has the same opportunity of making the same calculation as to the speed of the ball if he simply inputs all the information available to him. He in not unawatre of the speed of the train and how its speed will contribute to the speed of the ball... ok its different at the speed of light.
I found somehting today (that I left at home) in a mag re a star that is exhibiting time dialition and doppler effect simultaneously. I thought that would be a real life example to walk us through as to how they see time dialation .. but effectively they say because of the speed of the outflowing gas the effect is present..I admit a could not understand it on what was presented but as I said they claimed it was a "live" example so I will follow it up
alex

[xelasnave]

In the case of the different ageing of the person on Earth compared to the person travelling at C I cant see how the perceived differences translate to a physical difference in their ageing. The senerio is impossible to test in real life but I think people lose site of the fact we refer to "observations" of time change but surely to some degree all the observations made in these cases are personal to that observer and in the total picture are somewhat incorrect (except from the point of view of that observer). I can not see how observation changes anything in real terms.
I know there is so much I dont know that if I did know I would not say this.. but I do know a fair bit and have read outside Hawking to the point where I think I grasp a lot of this stuff. I think there is a slip between what can be "incorrectly observed" and the facts, which allows our minds to be carried in a dirrection that entertains things which are impossible to accept (time travell of a sort). The fundamental of frame references seems to me to give a message that the further one stands back the more likely one can make a fair observation but nevertheless that frame also is subject to the same scrutiny from elsewhere which may present yet a further varied picture to that observer.
But does all this whatching really change anything... each frame is relevant only to that observer, that is not big deal but this mental exercise (and others) used to explain the principles of relativity cause those involving themselves in explanations curiously entangled in a non real explanation of the facts... the only place to obtain those facts is from a distant observer who can point out to those on the train and those on the platform that all is not as they see it unto themselves.
alex

[Starcrazzy]

Thats exactly where the whole problem lies...we can't have all the information available to us (the uncertainty principal)..No one view is privilaged..The guy on the train has no reason to believe the train is moving..the ball still obeys all the laws of motion as if the train were not moving...ya see??the guy may know the train is going 100, but the ball doesn't..it just follows the laws of motion...so which laws are actually effecting the ball...it can't be the forward speed of the train or else it would hit the wall and bounce around like a crazzy flubba ball...as long as the train doesn't change acceleration, there is no change in its LOCAL experiance...but the guy watching from the ground can't say the same thinmg can he...if he were to try and make a physical calculation he would have to factor in its forward movement...so the equation he would observ would be a different one to the guy on the train...bbut NEITHER are privillaged..its all relative to the speed of the observer...RELATIVITY

[Starcrazzy]

Most people i know don't try and understand relativity, they just move onto the more tangable sides of physics, but to deny relativity is to deny so much of our current view of reality..Observation is only a small part of it, the effects of relativity are well documented and tested and is one of the most tested theory's in modern science and still it stands..after all this time..if only einstein could have got rid of the idea of a static universe we may be alot closer to the answer..It is quite simple (sort of) the faster you go, the less time you experiance (relative to someone who is standing still) well, as still as is possable, becasue absolute rest is a fantasy..

[Starcrazzy]

the ageing at different speeds is not impossable to test at all...it has been tested ,any times..they have even put matching atomic clocks on 747's and one on the ground and sent the plane around the world and compared the clocks..and alass, what do ya know, there's a differance, only a fraction of a fraction of a second, but remember these clocks won't lose half a second over 1 century let alone a few hours...so time dilation is a real consequance of relativity and very very tes table..:thumbsup:

[ballaratdragons]

Yesterday I read an interesting piece!

If a ship could travel faster than the Speed of Light it would see itself arrive at a later time!!!!

The Ship travelling at faster than speed of light would arrive, then the light from it which left at the same time obviously (which is travelling at the speed of light) would arrive at it's proper time, later than the first craft.

Hmmmmmm.

So, you could see yourself coming after you arrived. What a paradox!

[xelasnave]

How does the clock know it is in a jet?:) and the clock on the ground does it know it is on the ground and the other clock is flying by? One can accept two humans not being able to keep a grip on things but these clocks are inanimate so how is the principle extended from humans to clocks?:D
And the uncertainty principle is a problem for me thats for sure I never know where I am going or if I have arrived when I have got there..:shrug:
alex

[Starcrazzy]

ok.ok..the clock records the passing of TIME..it uses the spining of an atom as its measuring stick..1 second is like 9789999999999 revolutions of the electron of a certain atom around its nucleas..so after that a certain amount of revolutions of a NATURAL particle (which you and i are made up of bajillions of) 1 second ticks by..so if the atoms in your body obey the time of the clock on the airplane or better still the spacecraft travelling at cl;ose to C, then your body will age according to this timeframe..the very escence of matter is tied to time..and time is relative..c is not..

[robagar]

Uh, you're completely missing the point of relativity: No particular observer has a better view of "reality" than any other. Standing back doesn't give you a better view.

Special relativity is very well supported by experiment (see here (http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#Introduction) for a long list). For my money the best time dilation one is the study of cosmic ray muons. Basically, muons decay quickly and shouldn't live long enough to make it to Earth's surface. But because they are very fast moving the particles "internal clock" is slowed by time dilation, from our point of view. So they have enough time to make the journey throug the atmosphere and are observed down here.


Each moving observer really does have their own time. There is no "real" universal time. It's not a matter of perception!

[robagar]

The clock on the plane *doesn't* know it's moving - as far as it's concerned, it's ticking along as normal, which it is :)

[Starcrazzy]

exactly..:thumbsup:

[Starcrazzy]

i never said that standing back gives you a better view..i said no one view is privilaged...each observer can be at the same place in time but have experianced less or more time relative to the other..but they would each feel the exact same time has passed...think i just confused myself..lol

[xelasnave]

So the physical premise for the effect is that "speed" (a product of distance covered related to time and therefore T appears in the sums) has an effect on the speed of the particles in the atom? I guess this is how gravity gets drawn into the picture... it seems to be reduced to an expression of "acceleration". I find it difficult to accept that increasing speed has any effect on the "timing" of the atom which I see as an "artificial" extention. Now this is not saying that waht you put forward is not the truth I simply am saying it is a truth that so far I can not accept. I certainly am not saying I am right and the "others" are wrong..emphatically... but I think followers of the premise have made a fundamental error in applying what the principle of relativity says.. I think it is a proposition that is limited to the "human" observation and as such is simply a statement that things look a little different depending on where you are standing.. I really dont think the experiment where the clocks were carried is conclusive... one experiment and one draws a conclusion:shrug: ... mmm lets see you get a new drug on the market with one experiment:D . I say it may be a case where it was easy for the researchers to find what they found because that is what they expected to find ( almost a placebo effect)... the differences in the clocks demand many runs and samples should be taken if such is to be used as evidence.
Mind you I suppose as matter speeds up it will encounter more "gravity rain" maybe that "slows" the atom.:D :eyepop: :shrug:
alex

[xelasnave]

Er I was typing and missed a few of the posts. Thanks for the links Rob. AND thank you all for your tollerance of one seeking to chalenge the unchalengable and understand the mystery of the Universe. Still would like to understand the physical link between the clock and speed much better.
alex

[xelasnave]

Still within that link I found this.
quote
Experiments Which Apparently are NOT Consistent with SR/GR
It is clear that most if not all of these experiments have difficulties which are unrelated to SR. In some cases the inconsistent experiment has been carefully repeated and been shown to be in error (e.g. Miller, Kantor); in others the experimental result is so outrageous that any serious attempt to reproduce it is unlikely (e.g. Esclangon); in still other cases there are great uncertainties and/or unknowns involved (e.g. Mirabel, Nodland), and some are so recent that no consensus has yet developed (e.g. Nodland, Anderson). In any case, no reproducible and generally-accepted experiment is inconsistent with SR, within its domain of applicability. Yes in the case of a few anomalous experiments there is an aspect of this being a self-fulfilling prophecy (being inconsistent with SR may be considered to be an indication that the experiment is not acceptable). Note also that few if any standard references or textbooks even mention the possibility that some experiments might be inconsistent with SR, and there are also aspects of publication bias in the literature -- some of these papers appear in obscure journals. Some of those papers exhibit various levels of incompetence, which explains their authors' difficulty in being published in mainstream peer-reviewed journals; the presence of major peer-reviewed journals here indicates it is not impossible for an anomalous experiment to get published in them.
end quote.
In fairness it goes on given that qualification to deal with the results. So I dont think I am alone in questioning many of the "experiments" put forward.
I mean lets face it if you are doing a thesis as part of your degree on the subject you are not going to attack it like I could be interpreted as doing.
The clocks ..the differences is measured in nano seconds... I know scientist can read low numbers but doesnot anyone feel this is a big judgement to make on such a small observable "difference". To someone familar with the precission of atomic clocks are better qualified to comment but I am suspicious of the result.

alex

[robagar]

no worries :) the world would be very dull if we all agreed on everything.



you and me both!

The lovely thing about SR is the simplicity of the maths, but getting a physical gut feeling for the way it works is another thing entirely...

[xelasnave]

I think it is the simplicity of the math that to me "fools" folk:D . I am a nuts and bolts kinda guy:sadeyes: so of course it will perplex me. I mean one gets a little less confident in ones intelligence when presented with something all seem to "get" as a group but individually people will say and I quote a past remark from someone who helps me understand the concept..." but no man can understand space time"... and others when I reach the point of "well how does this work in the real world" I get told I should go to the Quantum Mechanics side of the room:whistle: . AND there are experimenters journalists commontators (with invalid input:mad2: ) who in seeking to jump on the band wagon cloud the issue further for folk like me.
Still how nice to have a question that presumably will keep me occupied until the end of my days. Already in my pursuit I recon I have read more than if I had of taken the subject at Uni... which leaves me realising I now I know less than when I started;) ..even though I actually know more:shrug::whistle: . But relatively I know little.
Thanks again

[josh]

Far out!
You guys are brainy fellas that for sure! Wish my brain could more easily compute the kinda stuff youre talking about
I never got as far as the rest of you as i really do have some difficulties focusing my mind when mathmatics are involved. It really does seem that the more you learn the less you know ie. with greater knowledge come greater questions, those questions seem to increase exponetially until questions asked become impossible{seemingly} to answer with provable facts.. until truly great questions are asked and we are left... well having an almost "spiritual" experiance. Well thats where i left off with this one, but i think that feeling is my mind going into damage control:D
Thanks for keeping this topic going, i know ive learned alot by reading your posts.
Thanks all:thumbsup:

[xelasnave]

Hey Josh I have no degree in Science or Math. My highest "scientific" achievement was to top the "trial leaving certificate" at my school in general science... that would not guarantee a last place in a combined sciences class. Having an aptitude for science I did Law so thats how smart I am.????
I love this stuff but regretably feel I miss the point, thats on a good day on a bad day I feel it is everyone else who has missed the point...
It has kept me reading since involving myself in this thread and although I could add more of my distorted views I think I will leave it for now.
alex

[ballaratdragons]

Ahhh, any comments on this Paradox?

[AGarvin]

If it were possible it would violate causality and totally stuff up some of our fundamental understanding of the universe, but since it's not possible according to relativity ........

PS. Love the 12"er.

[Johno]

There was a whole issue of Scientific American recently dedicated to time. I think it was April or May (I've lent the mag to someone else so I can't be sure). It was extremely interesting and one article discussed the twin paradox with some helpful diagrams. It's worth getting a copy if you can.

[Dujon]

An interesting subject.

I think, though, that an important point is being overlooked.

Visualise the impossible and simplify things a bit: A man leaves, or passes, the Earth at a steady but significant proportion of the speed of light. He is reading a book. The camera in his cabin captures his every move and transmits it via some sort of radio link. The receiving station back at his departure point records faithfully his every move (there will be a significant doppler shift in the transmission frequency, but for this exercise this can be ignored).

Let us say that, because he is reading about a complex subject or a copy of Playboy, he reads just one page per minute. So, after reading 60 pages he presses a button on his chair arm rest and then instantly returns at the same rate (I did say that this was impossible).

So, at the point he presses that button, what has the receiving station seen?

Well, assuming all the electronics are functioning correctly, it has just received an image of page 30. Why? because it takes the radio information a finite amount of time to arrive at the observation station.

What happens when our man turns back to the observation point? Exactly the same thing but in reverse. In other words his turning of the pages of his book will become closer to the one-per-minute mark but will not reach that frequency until such times as he (improbably) comes to a sudden halt or, again, speeds past our hypothetical observer.

But, but, but! Yes, by the time he returns he has indeed turned over 120 pages of his book. Both parties would agree on that. However the clock which our man wore on his wrist has recorded just two hours (one turn of the page per minute) as would be expected. The clock at his departure/arrival site though has measured double that.

Who is right? Obviously both are.

[xelasnave]

With the greatest of respect may I ask why when he pushes the button at page 60 the camera in the same room does not at that instant photograph a scene recording "page 60". The camera will not record page 30 for it is on page 60. It would seem to me that any transmission of information at the point of pressing the button, irrespective of how long the transmission takes to reach the recipiant, the information will be that recorded and transmitted ie a photo of the man in a room with a book open at page 60. I can not see how the recipant will receive a photo of page 30 when a photo of page 60 was sent.:shrug:
Did I miss something and barking up the wrong tree? :shrug:
I know what you say about the clocks is excepted stuff but I dont accept it :D (as otheres believe it to opperate) that it happens other than as an observational matter as I have said elsewhere around here and I am prepared to be called a fool for my belief, what I think or do wont change anything so hence my attitude:) .. I dont have a degree that a University will recall when they hear me rattle on:screwy: .. so I dont really worry:lol: .. I am going to look at what you said about the clocks and try and see what others see:)
alex.
alex

[Doug]

Well, at the risk of being irreverently irrelevant, what about time dilation with repect to the life of a photon?
Consider a photon being sent from here to a point 4 lightyears away, on a course that will cause it to be reflected back (by a conveniently placed mirror) to its point of origen relatively speaking. The lucky little chap will have travelled for 8 years, (4 ly there, 4 ly back) we will have aged 8 years, the photon will have aged 8 years, and red shifted the approprate amount. Now if the photon has not aged 8 years, but only a few months, then for that photon, it only travelled a few light months. But then in that case the amount of red shift would not be a faithful measure of distance because it would be a measure of distance measured under time dilation and not otherwise.:screwy:

Cheers,
Doug

[xelasnave]

In trying to recall one of the various examples used to explain “time dilation” I came up with my own light speed and time relationship. I have often said that the “time dilation” is an observational thing and not a reflection of reality. My example seeks to “relate” speed and time carefully so as not to confuse persons looking for time dilation when they do not find it. (I have posted this on astronomydaily.com also as I have voiced my opinion about the time thing there also)

In a star system not far away there are 9 stars (3 rows of 3) forming a “square” in one plan of space. The stars are 1 light year apart from each other. See the drawing herewith to see the layout.
O1 is a nearby planet from where our experiment/observation is launched, and CP1 Cp2 and CP3 are stars of known distances apart.
Three space ships leave O1 their mission to pass by CP1 CP2 and CP3, so as to calibrate their “speed” to their on board clocks. They reason that if they cover “one light year distance in 12 months they are travelling at light speed… this gives them a firm basis for calculations of time during the experiment.
When they pass CP3 their calibrations are complete and their respective speeds is such that they will each arrive separately at stars S1 S4 and S7 they will arrive travelling at light speed all at the “same time”. (each clock is in step with the other notwithstanding they are a light year apart.)
Each of SS1 SS2 and SS3 set their clocks so that if they arrive at the “correct” time the clocks will have counted down and start on zero as the first star is passed and then count off the years as the experiment progresses.
SS1 will pass S1 , S2 and S3.
SS2 will pass S4 ,S5 and S6 .
SS3 will pass S7, S8 and S9.
When SS1, SS2 and SS3 pass S3, S6 and S9 they are to complete a 180 degree turn so they all meet at S6 , parallel and travelling to return to O1.

SS1 will pass so close to O1 when passing S1 that O1 will observe them at the very moment they pass by (closer than 300,000 klms leaves the “gap” under one second). They will not see SS1 earlier than when it arrives for it is travelling at the speed of light and it will arrive at the same time as its image arrives. When SS1 passes S1 (and O1) they send a transmission showing their on board clock reads Time 0 years 0 days 0 seconds.
O1 were not sure when to expect SS1 but have decided that whatever time SS1 arrives at S1 O1 will set their clocks running from 0 years 0 days 0 seconds.

SS1 passes O1 and S1 and their clock is running perfectly showing they have taken 12 months from CP3 and as they pass S1 their clock is exactly on 0..
SS2 passes S4 and their clocks are 0 they send a transmission showing a photo of their clock at 0 however the transmission will not be received by O1 until another 12 months has passed.
SS3 passes S7 and their clocks are at 0. They send a transmission showing a photo of the clock showing zero. This transmission will not arrive at O1 until 2 years have passed.
At O1 they know that when each ship passes a star it means they must have taken 12 months to get to it from the other if they were in fact travelling at the speed of light.
When they complete “the run” past the stars they are to complete their 180 degree turn and so as all space ships line up for the journey home.

The following observations are recorded at O1

Day zero
O1 Observed SS1 at S1, set clock to zero zero zero and running.
Transmission from SS1 shows SS1 clock photo at zero zero zero

One year later.
Observed SS2 passing S4
Transmission received from SS2 shows their clock photo at zero zero zero

Two years later
Observed SS3 passing S7
Transmission received from SS3 shows their clock photo at zero zero zero

Observed SS1 passing S2 date zero plus one year
Transmission received from SS1 shows their clockphoto at one year, zero minutes, zero seconds when passing S2.

Two years and one hundred fifty and one half days ( .42927 of a day exactly) after Day zero a transmission is received from SS2 passing S5 showing a photo of their clock reading one year zero days zero seconds.
(Someone points out the crew must be getting younger but they are reminded that the image received was sent one year and one hundred and fifty and one half days ago and that the SS2 would in fact be half way between S5 and S6. by now)

3.2360679 years after day zero O1 receive from SS3 that they pass S8 and a photo of their clock showing it to read one year zero days zero seconds
4 years after day zero O1 receive a transmission from SS1 that they pass S3 and their clock photo shows two years zero days zero seconds
4.8284271 years after day zero O1 receive from SS3 that they pass S9 and a photo of their clock showing it to read two years zero days zero seconds.

4.8284271 years after day zero O1 received a transmission from SS2 passing S6 showing their clock reading two years zero days zero seconds.

The observers at O1 conclude that all ships are running to the same clock and are in correct positions to turn and return. Their clocks are correct because they checked them against distance (one light year between stars means that to cover the distance one must be travelling at C).
After each space ship passes the last star in its “run” it is to do a 180 degree turn and meet at S6 travelling back toward O1. They are to complete the turn manoeuvre in two years. The ships all meet at S6 and head home. They have decelerated to half light speed and have…2.2360679 light years distance to cover to get home. They decelerate further and land on O1 5 years later…they have travelled for 9 years each since passing S1/S2/S3
They have shown that their clocks ran at the same speed during the experiment as the clocks set on O1 on day zero zero zero. All agree that there is no evidence of time dilation.
So where has it gone??
Finally the only conclusion reached is that “time dilation” is present in observations simply because light travelled at a “speed” and as such we can not be privy to what happens everywhere in the Universe “instantly” it does not mean when someone travelles at the speed of light they age any different to any one else.
What have I missed no one got younger or older than expected????:shrug:
alex

[xelasnave]

Gee I thought by now someone would have been able to tell me what I am doing wrong here:shrug::help: . It is probably to lenghty to look interesting..dam but I could not make it shorter:lol: .
If I am not wrong doesnt that demand a rethink of the atomic clock experiment and others seekinjg to put forward what I believe :screwy: to be an unrealistic proposition;) . Please put me out of my missery I would be as happy either right or wrong it just seems to me that there must be some trick played in other examples of similar kind:D .
The only time dialation parradox I see is that there is no paradox:shrug: .
alex.

[xelasnave]

clearly those who feel unqualified to comment will not and those qualified to do so feel it is beneath them and will let me wither, add to that it is plain boring I feel I will not see anything resolved. I was not seeking to be argumentative but felt my experiment offerred something to consider.
alex

[Doug]

Alex, I feel underqualified to answer so I will; but not yet....................fools rush in and all that.
Your poser requires some digesting, and I'm supposed to be preparing an article on some post processing issues. distractions....... distractions......... A quick look at your post, it seems to be similar to a thought I had years ago when I was clear headed enough to think, but too young to keep focussed....so many 'hevenly bodies ' to contemplate and all that:whistle: .
best,
Doug

[Starcrazzy]

i started to read your post and only got this far.."I have often said that the “time dilation” is an observational thing and not a reflection of reality. "

time dilation is a well documented, highly experimented and tested aspect of reality and a direct consequence of relativity.

They teach this in high school physics, i have the text book in front of me and will quote the opening paragraph of the chaptyer devoted to "time dilation"

Time dilation can be generally stated as follows: the time taken for an event to occur within its own rest frame is called the proper time (t0).Measurment of this time, (tv) made from any other inertial referance in relative motion to the first , are always greater..digest that for a moment...ARE ALWAYS GREATER...back to the textbook,...
The degree of time dilation varies with the velocity.
It can be more simply stated as :moving clocks run slow.

The text book goes on to show the formula's (quite simple ones really but to hard to type, the symbols just aren't on the keyboard) for working out the exact time dilation factors when givin speed and distance are factorised..

Why do we keep trying to reinvent the wheel??
Time dilation is as a real as any other thing we can "observe"..It can't be denied, or at least, while no other theory has been put forward that can account for the annomolies observed in respect to travelling clocks..

[xelasnave]

:hi:
Thank you Doug dont read it just look at the pictures:D .
Thank you Starcrazzy for your interest and input:) .
Well if it is so simple to explain and you have the text book in front of you I sure would appreciate being shown what the heck I have not taken into account:) .
I have looked at the travelling clock experiments I do not think a couple of nano seconds offers conclusive proof, I can not quote to you the % variation upon which this conclusion is draw but it is unsatisfyingly minute, the other examples of experimental observation relates to estimating the time associated with a "dieing" subatomic particle whose lives are extrodinaryily short and again I feel a rather a dubious conclusion:shrug: . The only testimony to the age of these particles is what the theory dictates.. the theory also predicts many more than they find, again hardly conclusive and open to other alternatives no doubt. So I really dont think it is a closed case well certainly not for me:D .
The reason why I have done this is to try and understand how playing these mind games (I refer to the mind exercises like the train and the platform stuff) the contructers of the formulas arrived at them.
To me I have related things in such a way that I thought there could be no doubt that we are dealing with perception not reality.
My inclusion of the following was to draw attention to that aspect..

Two years and one hundred fifty and one half days ( .42927 of a day exactly) after Day zero a transmission is received from SS2 passing S5 showing a photo of their clock reading one year zero days zero seconds.
(Someone points out the crew must be getting younger but they are reminded that the image received was sent one year and one hundred and fifty and one half days ago and that the SS2 would in fact be half way between S5 and S6. by now.

Now that is perception, sure the clocks would appear to be slower but that is simply because of the increasing distance..if you look at what is going on on board and what the observers see of that moment and how long it is before they get to see it... well there is no need to assert clocks run slow to not leave the observer with that impression.
I found the only use of the space time geometry was to calculate the time the transmissions took to travell to O1 from each ship.
Can you see why I conclude it is a matter of observation by the course I have followed? I can not find another conclusion than the one I have come to.. again thanks for your interest and input and if you can see the specific flaw in my approach please let me know.
alex
alex

[AGarvin]

Trying to understand many of the concepts behind relativity frequently raises these types of questions, but the fact is that no matter how many ways you think of to take pictures of clocks in misguided thought experiments, time dilation is a very real property of the physical universe as we understand it, and pretty much the entire professional physics community agrees and has agreed for decades. These "unsatisfyingly small" amounts that are cited as experimental proof can be exceedingly large amounts in the world of physics.

Time dilation centres around the invariance of the speed of light for all frames of reference and this has been included in a whole bevy of areas from the Lorentz Transformations to Schwarzchild geometry, and these are not thought experiments, but solid mathematical theories, many of which are backed by observational or experimental proofs.

Yes, future research may have us alter or even rewrite areas, but there is a much bigger picture here than simply arguing it is wrong because it is not understood.

[Starcrazzy]

yes..these unsatisfyingly small amounts of change are more then enough to prove the theory...the laws of physics are quite often dealing with very small numbers....but i put it to you like this...if i could defy the laws of gravity by floating a mere 2 inches off the ground indefinatly, you may call this "unsatisfyingly small" amount , but it would be enough to completely rewrite evry textbook and and cause a rethink on all of newtons laws relating to gravity..If i could build a machine that could teletransport 1 single atom around the world to appear in another place instantaneously, i would have made an incredible discovery and probably win the nobel prize...would that still be an unsatisfyingly small amount to prove to you that the scienece is possible??where would the line be drawn...what is satifying??transporting an atom?an apple?a person??a planet??what is considerd large??a planet may be huge to you and me, but in the scheme of things doesn't even rate a mention..nor a does a mere galaxy for that matter...
Time dilation is more then an observable annomaly...
The changes may be minute, but if you start to relate themn to a space journey by humans where we travel close to C for a considerable amount of time, the numbers start to add up into quite sugnifcant factors..so much so that century's will pass on earth while mere years have passed aboard the ship..and this obviously opens a can of worms with regard to paradox's and so forth...like this, in the century's that pass on earth, one of the crews offspring may invent a new type of propulsion system that would enable the great great grand kids of the original crew to actually beat there great great grand daddy to the destination...

Or ponder this one for a while...A man travelling at C looks in a mirror in friont of him...does he see a reflection??

Enjoy

[Starcrazzy]

ok..ive had a close ;look at your space ship experiment...the flaw (imho) is this...they are all travelling at C..try sending the picture back to earth where they all started from and recalculate...then you will find the annomoly...you have nothing to "relate" the speed to if thay are all travelling at C becasue they are all in the same innertail frame of referance...

[xelasnave]

Thank you both for your input.
I appreciate the delecate manner in which you each have dealt with the matters. I trust I am not alone in the frustration of not understanding these concepts as you both sound knowledgable in the area and I suspect have been earlier presented with similar questions.
I take the point of "smallness" very well put in both cases. I further suspect part of the problem arises from the use of "examples" and "mental exercises" to relate these complex concepts to laymen (such as I ) via the popular book sold on a newstand not out of the University Book shop.
Thanks again for your interest, input and help
alex

[xelasnave]

further thanks for the mirror at c thing I hope you have an answer after I give it my best
alex

[xelasnave]

Sorry Starcrazzy I missed your last post re problem with my example thank you I will go over it with that in mind.
Re Mirror reflection etc at c where is the light that illuminates the mans face?
alex

[Starcrazzy]

well, thats the problem isn't it..if he is travelling at C how can any light reflect from his face onto the mirror??in order to be just in front of him it would need to go faster then C, and we know this isn't possible(don't start me on this subject..lol)so for that matter, could the man see his own hand held out in front of him...arrrggghhh...this is where all the confusion comes from....this isn't the answer by the way...i will give a detailed answer later...after your head has exploded (like mine)..

No probs xelan..I deffinatly don't profess to understand the theory's completely..not many could say they do, but without experiments like your space ship one, no-one would be able to understand any of it..its all mathmatical..don't abandon your space ship experiment, just modify for the earth bound frame of referance, and you will be onto somethin there i think..if not least, another way of explaining the annomoly...
cheers

[Dujon]

Mr Evans, sir.

That's one of the corner stones of the Theory of Relativity. That theory suggests that anyone anywhere will measure the speed of light (in a vacuum) as constant. This, of course, assumes that the universe is the same throughout its whole structure.

Thus the shaving spaceman will see his reflection just as you do each morning when you look in your bathroom mirror - regardless of the source of the light.

Who is to say that you are not travelling at the speed of light at this very moment? I would guess that someone in a galaxy far, far away - from their viewpoint - would say you are. By the same token you would say the same about them.

Imagine two cars travelling on a moonless night, both without headlights, passing each other. By pure chance both drivers activate a cigarette lighter as they pass by. Who is going at what speed? You can say, "Well my speedometer tells me I'm doing such-and-such a speed" just as can the other driver.

Now stick them out in space - doing exactly the same thing but without a reference point. By that I mean that neither driver has a speedometer that can tie them to a fixed point.

Who is doing what speed then?

[xelasnave]

Doctor Starcrazzy
I need a quiet place to do it, just with my example working thru that got me twisted enough and that is very straight forward really but thats why I built it very step by step and as I thought tie all the necessary bits together. As I said someplace else or here I will go home, I have 2 boxs of chalk, blank walls and non one to care what I put upon them.. I can map the whole Universe if thats what it takes:lol: :lol: :lol: leave it with me but the mirror thing sounds only a cosmetic problem:lol: :lol: :lol:
Doctor John
You said "Who is to say that you are not travelling at the speed of light at this very moment? I would guess that someone in a galaxy far, far away - from their viewpoint - would say you are. By the same token you would say the same about them"
I expect that this is the suggestion I would read into red shift upto 12,000 klms per second I believe mmm considerably faster than light .. thats all I need how does ones get their head around that:shrug: .
I appreciate the cars passing in the night and the need of the speedo etc in my example I sought to tie everyone up with a reliable reference against the most "absolute" reference I could include..this being.. known distance (between the stars) and a method of relating the passing of each ship of a star by the work back observation of their clocks which are really the speedos with the needle stuck on c...
When the ships pass their first star their clocks are running and will be checked during the passing of the stars, their time related to the speed which is necessary to make the distance within the time and thus send an appropriate photo. All I am saying is my limited appreciation of the problem suggest to me the first thing to nail down is methods of "cementing" those relationships.. that was I thought a sucsessful construction.. (a guy on astronomydaily was concerned about the difference each star would bend space time and thought that a larger dot may represent a larger star.. so the model needed work to be consummer friendly so I changed the "massive" stars for some non interfering foam spheres.. Starcrazzy has suggested some work of possibly more productive outcome and I have yet to consider how on the next trip we can keep the crews clean shaven;) ...
again thank you all for the interest and input and thanks for the home work:thumbsup:
alex

[Shawn]

Thought Id join this thread, and chuck into the hat this statement.....Light speed is not constant universally, time is something we created for our conveinience, the two must not be campared nor confused. I agree that distance over time equals speed, and every othe convolution on that formular. but If I suggest , time not constant totally in relation to the observer, Light speed not constant universally, then the equation has no answer. the twin paradox proves that doesnt it ?

[Shawn]

For example, observation, someone bought up the bouncing ball on a train scenario, the stationary observer would see the ball covering a greater distance to the chap that was bouncing it, hence by simple math the ball is going faster....NO... Get a High speed camera and pan that shot, and you wouldnt even know he was moving, hence no change,,,the same rules apply,,we have an extremely narrow window of observation,,,the change on the scale we are discussing is considerable... we can not see it , we make asssumption on our narrow view of things...just a thought

[Shawn]

Dujon ,,,just read your reply, I think thats closer to the point...I think you on the right track...

[xelasnave]

I am asking this because I am not sure but does not space time geometry depend on c as a constant? are you saying it cant therefore be adequate because of its ridgidity (in your view) being tied to a constant c? (if it is as I recall) Or have I missed your point totally? sorry but there is no point me misunderstanding your meaning if it is to be useful particularly as you were good enough to contribute which I thank you for doing.
alex

[Shawn]

Your right there Alex, but do we know that C is a constant, I strongly suggest its not, as per my thread,,,repeated comments in this one, and other physicists worldwide and stick thier neck out, only to get thier heads cut off...

[Shawn]

Lets take mitchelson morley,s experiment for example, just look at the microscopic area of space that was measured, can you trust results based on such an infinatesimaly small window...

[AGarvin]

So what evidence do all of us highly educated and experienced theoretical and experimental physicists have to even remotely suggest that the speed of light is not invariant; thereby denouncing one of the corner stones of our current understanding of the universe.

Do we have an "Alternative Theory" board?

[xelasnave]

I found a site that makes my efforts to figure it out look lame..( in energy that is no comment as to the correctness or motive of this fellow) but he has rather stong views on light speed time dialation .. well he seems to have made a lifes work at proving the Dr. wrong, establishing the Dr as Top Gun if that is who he is after... however I found it interesting if you are interested
http://members.aol.com/carmam1534/Hollings.html#clocks
He recons the clock thing turns on whether its a pendulum or atomic clock so that new to me... I have yet to look at it all..I was looking for something on the light speed measurement. This fellow made the comment there that the medium through which the light travells is relevant.. and suggestted the probability of varience for c.
alex

[Starcrazzy]

Ok..first of all..Dujon,....i know i am not traveling at C..i know this because i am able to accelerate my mass away from my computer to the fridge..if i were travelling at C, the energy required to accelrate my mass would be infinate...as in, not definable....nut as im sure your aware, it requires quite little energy for me to go to the fridge..(well, enough to make me only do it once or twice an hour..lol)

Sirdystic..Your statement that we invented time has me baffled...time was tickin away way before you or I or anyone else was around to invent it..matter itself cannot exist without time..time and space are connected..are peices of the same stuff..and...the speed of light is constant...thats where the whole theory gets its fuel from..its constant nomatter what speed the observer is travelling...with regards to the ball on the train, whos' point of view is privaliged??the guy on the train, or on the platform??the answer is neither...both views are acceptable with regards to the physics involved,ie, neither is breaking any rules, but, both views do not agree...its one of the fundemental laws on which our current view of rea;lity is based..its a pillar of modern physics..many ..many brilliant minds have thrown experiment after experiment at it, and the theory still stands...

cheers

[Shawn]

What i mean, Starcrazzy, is that we only distinguish one moment from another using a measurement called time, based on the """theory/s""" of modern physics. this too is a variable, if c is not constant. seems a fairly straight forward question. what speed is light travelling at the event horizon of a black hole, either from our view or the view of someone that was unfortunated enough to be there. ?.as for poor person 2,, I wonder what his watch would be doing.. measuring what... Or am I just over simplifieing something this so I can get my head around out and at the same time flying in the face of many brilliant minds that have made a lifes work of overcomplicating it.

[Shawn]

xelasnave, that link you posted is what im trying to say here, but hes much cleverererer than I and can back it up with ,,,big sums:P

[xelasnave]

You must appreciate that he is seen as a crackpot by the converted, however he has at least tried some explanations for the against case.
I must say looking at his site I wonder why I bother at all but sadly he and I must have a similar problem of acceptance.
Time is a curley one.. if you think what we use as the prime unit (a year) that is something that could not have exsisted 7 billion years ago as there was no Earth (a reasonable presumption) to orbit the Sun and provide the marker... and no doubt from that approach each year is slightly longer or shorter that the one proceeding it... is time therefore flexible because the standard of measurement itself can not keep constant and consistent time...and as such backhandly says we therefore invented time upon our first realization of night and day... for the other side a lodgical reply to that proposition would suffice.
But obviously the acceptance of the time dialation thing is something I can not bring myself to do at this point as I simply have no faith in its extrapolation into reality.
In the example I offerred if nothing else it has allowed me to point clearly to my proposition and demonstrate why I can not accept the effect is real.
Past this point it can only become a matter where I seek to prove I am right and others are wrong which realistically is a no win situation. These arguments fall into a group where if one feels they are losing ground it is only because they have failed to make their point clear enough to be immediately excepted by those present... I teeter on that point.. and pull back. I need not to shore up my confidence as a debater using this medium so I leave it to be what it is ..my comments on a impossibly hypeathetical situation that can not be decided by proof acceptable to me in my life time.
Still I doubt if I dont have more to say in the future.
alex

[Starcrazzy]

hehe..i love how to irriterate your point you use the one area in all of physics that all the maths break down..the event horizen of a black hole..This is te one place physics can't go, and you bring it up to try and explain a theroetical theory...most physiasist's stay well clear of these "horizens" for what they represent is beyond the realms of mathmatics...i refer you to the black hole paradox (stephen hawking's) and many others..
where did we decide that C is variable??
have i missed something??
cheers

[Starcrazzy]

xelesnave..don't stop bringin it mate..there aren'yt enough of our type on this forum...and i enjoy immensly the torment...some astronomers look up and say, wow, isn't that nice...others look up and say, ..wow, isn't that nice, what the hell does that mean, how did that come to be there, where is it going, what does it have to say about where i came from...what does it have to say about where im going...and the big one...how the heck does that work???...lol
cheers

[xelasnave]

I want to know all that is out there and how it works that for sure but I also want to know the purpose of the Universe. To what end do all these bodies interact? what balance or goal is being sort? and could there be a God and where does he live? are his parents still alive and where did they come from and why?.
and if it all works out the way it has been planned what next?
Other than that nothing much really...
alex

[Starcrazzy]

haha..goodluck with that mate...similar to my own search...has been a long road..my parents were ministers and then school teachers(science..)and no, the irony is not lost on me..lol...

[AGarvin]

Wow dude, don't want to know much, eh . . .

Just don't confuse the physical universe with the philosophical. On the physical side, the best thing anyone can do before they go deviating off on alternate tangents along the lines of "the speed of light is not constant" is to not only understand what is currently accepted physics, but why it is currently accepted physics. This keeps the "alternate" in perspective. Some folks make ridiculous statements without even understanding the magnitude of what their saying. Virtually all of these cranks get shot down fairly readily ... be careful of what you read on the net.

Besides that .... go for it man ... :thumbsup: !

[xelasnave]

And the philosophical side we have:shrug: ?????
I appreciate the trap of the net;) .. I even found a site that used current formulea to prove that gravity pushes as oppossed to acting as an attractive force,(which is supportive of my concept of its action), needless to say I dropped it in the running thread on astronomydaily.com:D but the problem is this fellow was swimming against the tide so I doubt I can really use anything he says in support of my graivity rain idea. But I will and I did:P .. so if I am not beyond doing such think of the liberties some may take with the facts:eyepop: .
I am aware of the morosophic nature of my quest (s) and knowing same it helps protect myself from myself and the "crackpots". However there is probably a better commercial future in promoting oneself as a crackpot as there are countless examples of this being a sucessful financial approach... so I think I understand where they come from.
I had thought of a book..."Gravity does not Suck" :lol: :lol: :lol: a title which dispite the boring contents would probably be a best seller by virtue of the title alone but I think I will continue to observe and only lightly participate via little discussions such as we can enjoy here;) :whistle: .
There is a list of qualification on the net someplace giving points to determine if you can fit the crack pot:screwy: catagory... I am not there yet but I know what is expected:lol: :lol: :lol: .
So it could be done:D .
alex
alex

[Shawn]

Hi Starcrazzy..
Sorry missed the discusion tonite, my time got dialated,:D... The Speed of c may very well be constant, Im merely suggesting that mayby it is not,, previously I pointed out that our window of measurement in infinitesimally small, and maybe, just maybe should not be trusted. You did miss the point somewhere I think...This whole topic as has been said is not a case of proff or disproof. more a case of questioning the established theories, and yes I do believe they are all still theories as no absolute proof exists. and for the meantime I doubt it will,

Cheers

[xelasnave]

:hi: Good morning all is it not a wonderful day:) .
I have been told in another forum that in physics we dont necessarily need to know why:eyepop: ... mmm I say we need more why and why not.. thats the role of the crack pot and the futurist;) .
History tells me that humans have a tendancy to resist change generaly so any accepted theory will be held onto until there is no hope left for it. New theories are made to fit the exsisting theory not the other way around (even simply to run it by)
At a Xmas party of conveyancing lawyers as a young clerk at the coal face I made the observation that there were many areas in the conveyancing system that could be streamlined and thereby reducing costs that could be passed on to the client. Did they all gather around to hear how it could be done? No strangely:lol: :lol: :lol: ... in those days one needed to make 6 "enquiries "of Government Departments as to the possibility they may require all or part of the property being purchased... I think today that number is up to 30...The empire grows:D ... The fact is the Torrens title system (Real Property Act) provides a system taken by Mr Torrens of South Australia from the system of registering large ships. It was a world first..the best system in the world to date. (The previous system required all documents relating to the property from the year dot had to be checked each time the property changed hands..in case the lawyer who did the job 60 years ago missed something that has not come up in sixty years:shrug: )
There is a central register under the Torrens system where one copy of the title is kept and a copy of the title is held by the owner or Mortgagee. Under such a system why is it necessary to "enquire" which Department may need the property for a school or a highway..Any requirements could be simply noted on the title (as is the case for a moprtgage, easement, covenant, lease over 3 years and other items) saving the need for any direct enquirey to the department... well the only reason why not is that the empire size will be reduced therefore it is not done that way. The irony is Torrens "invented" the system to remove these silly duplications. The empire however rocked from not being able to read and re read documents of ancient kind but nevertheless managed to complicate things enough to keep the empire mostly the same as it was before..same time to do the job we will just find other stuff to worry people with.
In the world of physics things should move slower still (for safty) however I suspect a similar condition exists in that world in fact such a condition exsists wherever there are humans engaged in an "empire".
However history also tells us that many excepted traditions beliefs systems and theory fianlly fall to the pressure of a better approach.
I sence the scientists of today feel very sophisticated to the point where that history could only happen in "the olden" days and they fail to appreciate there is nothing special about their time in history that insulates them from a major change in thinking...was that not the situation when Relatively entered the room?
My preoccupation with gravity leads me to believe that although the space time theory explains and observes results it does nothing to explain the nuts and bolts of any interaction... this is the job of quantum mechanics.. firstly why do we need a separation.. why has the inconsitencies between quatum and relativity been left open..is that two empires competing for their realm to stand over the other.. to me it is unacceptable (personaly ..does not mean the world must change to suit my dictates of reason) and that is why I am driven the way I am. Not for fame and fortune either ..fame and fortune is a backward step for me..I took years escaping from those masters and have no intentions of ever going back...not even for a book signing or to appear on Rove live:P :D :) .
However few enjoy the motivations I do and are not able to rock the boat.
If you dont join the empire you are on the outside and therfore a nutter.
I may have different ideas but I believe I am not swayed by fantacy or illussion, nor by pressure to accept the accepted without question...
Its a big job and I am happy to do it for my own reasons which is ..I want answers that are not clouded in mystery and ideas that can be proved conclusively ..if not I dont use them other than to talk with other humans.

alex

[Nuri]

I just read the entire thread with great interest. I like SirDystic's view about time being a human invented concept. Can we say that it only exists because we measure it by inventing our own reference points based on other objects in the universe (Sun, Earth, Moon etc) which are interacting with each other?

If we assume that "nothing" existed before the big bang, then there was no no reference point for time... Does this mean there was no time because there was nobody or no way to measure it? I'm no scientist but, do the laws of physics state that time physically exists, or is it just a measurement of human perspective? (if that makes sense)

[xelasnave]

Hi there Nuri :hi:
Personally I find the concept that nothing can exsist as unacceptable:D ... if there was literally nothing...well we have nothing to build anything with.. something from nothing can not be..nothing from something can not be..
an expanding Universe into what medium does it expand.. nothing? It is something we think we know but find me some, as far as I can tell such a thing will not be found in our Universe or outside it (if there is an outside which there is not) With all this in mind it makes the big bang difficult to envisage for at that point we are asked to accept the unacceptable.. something from nothing... so far religion can only provide an answer.. but again I doubt if God would exsist in nothing. The fact that he was present says ..now that is really something:scared: . So dont stop at nothing its inclussion avoids facing the reality of its non exsistence:eyepop: .
The laws of physics are the laws of physics not the laws of the Universe the laws of physics merely purport to measure and quantify the observations of humans so in that context the recording and observation of time is a human invention (but a very useful one).
Any comment on the thrust of my proposition that time dialation is an observation produced as a result of the maximum speed limit? and thank you for your interest and input.
alex

[Nuri]

Alex,

We can't prove or disprove that "nothing" existed before the bang. However, we do have cosmic radiation measurements of a big bang 13.7 billion years ago, and other physical evidence that supports expansion. But we cannot (currently) measure what existed before the big bang. Sure, we can argue what "was" or "wasn't", but it would all be pure speculation. Given that most of what we DO know about the universe is less than 50 years old and that we are regularly discovering that we actually know bugger all (eg. "event horizons"), it's safe to say we've probably discovered only a fraction anyway :)

Re: "perception" vs. "real" time dilation, the view that makes the most sense to me in this thread is this by AGarvin on the previous page :

Basically, it centres around the fact that the speed of light is the same for all observers. The stationary observer will see the light travel further than the person in the ship will for the same event. If the distance is further, but the velocity is the same, then the time taken must be 'longer', or dilated.

To me, this is not a perception. Assuming that C is definitely constant, the observer will actually live longer than the traveller during the period of the experiment. But if nothing can move faster than C, then we get the paradoxes mentioned earlier, like not being able to "see" your hand in front of you travelling at C.

... As I said, we know bugger all... but tallking about it is a *great* way to produce sparks! :)

[mickoking]

IMHO I belive something did exist before the Big Bang. It makes no sense to say something (the universe) was born from nothing. Cause and effect.

[xelasnave]

I am not unaware of the background radiation data, what if that is missinterpreted data... maybe its the radiation from beyond what we call our observable Universe or something else... however it fits the expectations of an extrapolation to a point drawn backwards from the observation of an expanding Universe.Now although totally against the grain expansion to me does not add up... the question "into what medium does it expand into" until answered in my mind will leave me at that point.
The two alternatives..firstly that the Universe has always been and always will be and the second that the Universe started at a point smaller than a grain of sand and within the grain of sand all was contained all to build todays Universe..either is not easy to accept.
Our time at the problem is miniscule to the enormity of what we seek to know as you have observed.
Thank you for your input and statement of your understandings and belief
alex

[Doug]

Pardon me chiming in rather late in the piece, but I have issues with time dilation, and the experiments that are supposed to 'prove' same.
I have been informed of two different experiments, both of which are supposed to support time dilation, but (I think) neither results agree on degree.
The first experiment involved Jet setting one clock around the world and noting a slight dfference in their time readings. The second test involve taking one of two synched clocks from Greenwich and leaving it atop a rather high mountain for a year, then comparing the two.
The first test was acclaimed a sucsessful demo of time dilation due to V.
The second test was aclaimed as proof of time dilation as a direct result of G. Which test is really demonstrating time dilation if indeed either?
Just how scientific are those tests?

If velocity causes Time dilation, the many cycles (East to West orbits) would be necessary in order to produce a statistically unblemished result. For example 500 East to West orbits in a satelite, would tend to reduce any effect of delta v and delta g on the data collected. It is not that these factors I mention must have any effect on time, but they very well might exert influences on the atomic resonance frequency, possibly due to minute changes in the physical size of the cesium chamber, or maybe even on the resonance behaviour of the cesium atoms themselves.

If Gravity caused time dilation, then to be statistically certain of the accuracy of the data, perhaps many tests at various levels of G would be required. But as Earth bound altitude increases, so does V, so this test could become rather messy by its very nature. Perhaps a clock left on the Moon (West to East orbit) for a few decades might be statistically pure enough for such determinations.

So I think time dilation is as yet unproven scientifically, unless statistically sound tests similar to what I have suggested have indeed been carried out, and I haven't heard of any such.

Cheers,
Doug

[xelasnave]

I have yet to do more on this but I am confident I will get to the bottom of it.
The weight of opinion that it exists as a real thing is overpowering it is a pity that hte experiments can not provide more samples... I am prepared to conceed (and I have) that the "unsatisfyingly small measurements" involved are suitable and sufficient for physists who are more capable of assessing the data... however the sample issue or the lack of suitable samples to me is unscientific... the experiments of which we speak would carry more weight for me if we had say 100 clocks on the mountains of the world and a clock in every aircraft ... who will be the first to say that is an unreasonable expectation. I look all the time on the net re this stuff and you either get the for or against, if you are for you will only support the proposition if you are against you are outside mainstream and that puts you (and I must say usually correctly so) in the fringe where no one wants to say they are your friend.
The issue is important to me and has assumed obsessional proportions (as has gravity, the Universe nature and the line up of gallaxies) but I feel I can still give something fair scrutiny without bias.
I welcome your late entry and input your views are of interest to me and I thank you for taking the time to share them. This is an easy area to avoid because to offer counter views brings the glance of folk who will instanly believe they know more than you possibly could on the matter, and I know there is a tendancy to "look down" upon one who does not buy the proposition as if one were uninformed and bordering on crack pot.
Fortunately to be called acrack pot is a step up for me, thats higher recognition than I am used to so I really dont care if I anm labled such.
alex

[Doug]

I should have discussed the possibility of the frailty of Atomic clocks with a tad more clarity.
I suspect that "Elastic Inertial Compression and Rarefaction" due to delta v, will very likely be present, and its effects will also probably be as statistically uncertain of proof as are current time dilation tests themselves.

Cheers,
Doug

[AGarvin]

http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html

[xelasnave]

:hi: Great stuff:thumbsup: . I have been there before refferred for help with my nonbeliever ways. I thought I recognised the name (Baez) you may like this;) .
http://math.ucr.edu/home/baez/crackpot.html
I failed it first time but I have been studying and will be trying for a higher score next time:lol: :lol: :lol:
Thanks for posting that link there is not much missing there.
alex

[xelasnave]

Hey should I take this personally???:lol: :lol: :lol: (from the index)

"20 points for naming something after yourself. (E.g., talking about the "The Evans Field Equation" when your name happens to be Evans.)"
So the gravity rain thing has to be renamed "the xelasnave theory of UNIVERSAL PRESSURE"
(you get more point the more capitals one uses so I am catching on:D ) I found it (the index) personally helpful as I thought my symtoms were simple cabin madness but it was grander than that it seems:screwy: .
Hope you get a laugh going thru it (the crack pot index) .
There is also a description for my problem "morosophic" where one sees every piece of new information that presents as being supportive of ones ideas. Hence my Professor Morosopher title in the gravity thing at astronomydaily.
All of this helps keep things for me where they should be but it does not frighten me from enquirey and objection I enjoy the area too much to be frightened away. Time for another quote from the Doctor and what Stephen Hawkins said about black hole radiation:D .
alex

[Doug]

Good Grief man! I glad you posted that last link. I was begining to think I would have to take him seriously. The mind that would revel in such basic ridicule is not a mind to be trusted.

I found this staement on his previous page of signal interest.

"They flew atomic clocks on commercial airliners around the world in both directions, and compared the time elapsed on the airborne clocks with the time elapsed on an earthbound clock (USNO). Their eastbound clock lost 59 ns on the USNO clock; their westbound clock gained 273 ns; these agree with GR predictions to well within their experimental resolution and uncertainties (which total about 25 ns)."

I think this above contribution by Baez justifies skeptical reception of much so called scientific proof by honest enquirers.

Let us assume that these flites were both non stop global circuits (which they very likely were not).
Let us assume that the East bound clock did in fact loose 59ns. and let us assume that there was neither head wind nor tail wind(since no data is cited) Let us further assume that the flight took place at near enough to zero latitude and that the airspeed hence ground speed was 500km/hour.
Further, let us assume an equatorial circumference for the Earth of 42,000km and this figure including the increased circumpherence due to the flight altitude.
So after a flight time of 80 hours our east bound clock will have travelled the 40,000 km circuit required to bring it back to its point of origen.
And so after 3 1/3 days it has lost 59ns.

Now what about the west bound clock? The aircraft carrying this second cloch also has an air speed of 500km/h, hence a ground speed the same.
But because the second clock is being flown in a direction 180d opposed to the point of origen, the overall flight time will be shorter than it was for the East bound clock. therefore any hypothetical time dilation will be of lesser extent than for the east bound flight. Since 'sence' is missing from the GR equations, if this test had indeed agreed with the theory of GR, the west bound clock would surely have lost some time, but not as much as the 59ns lost by the east bound clock.

You see this so called experiment has introduced direction into the arguement, such that the best match to it would be that if a space ship travelled to aCentauri, on board time would be compressed, but on the return flight, time would be stretched back again, but by a greater amount. :lol: :lol: :lol: :lol: :lol: :lol: :lol: :rofl: :rofl: :rofl:;that is if aCentauri lies to our east??:lol: :lol: :lol:
That is where the data supplied by Baez leads us. But don't worry, you can go as far as you like at light speed, just don't think of comming back!

So the data supplied taken at face value, suggests that a space craft travelling east, then returning would actually return before it left................I think not!

Maybe time dilation only exists on planets?? after all, east and west have no meaning in space.

I remain very much unconvinced of time dilation not only by the appauling lack of statistically compelling data, but also by the tawdry attitude presented by one of its cheif appologists as shown by the link you supplied Alex.

cheers,
Doug

[Shawn]

Time dilation is something we say that happens under certain circumstances, so that we dont contradict the c=constant that underpins our understanding of the universe. and upset a whole bunch of genies arses to boot. Where as c being constant contradicts our obervations under certain circumstances. since we base our measurement of time on c being constant, this discussion could go on forever, ie time dilated :D...all of the anomolies and paradoxes could be explained if c is not constant. It really couldnt be any simpler could it..... That should stir things up a bit, hey what old chap...;) .

[Shawn]

I guess what Im saying here is that light obeyes the same laws of physics than everything else, tho limited by its infinitesimally small mass" and there is another subject of debate" take for example gravitational lensing, or even chromatic abberation,,a bit extreme...but yes different distances same time..if you could ever measure it,, its all relevant..we measure huge distances by red shift. is it not possible that light does gradually slow down and that these objects are not as far away as we measure them to be. the distances are overwhelming, we cannot expect to get an accurate picture in our tiny neck of the woods...

Ive repeated myself somewhere Im sure, Id like to know just how many others think that just maybe, what we think we know is based on a theory that is fundamentally flawed..

[Doug]

I'll put my hand up:hi: .
But wait..........Gravitational lensing?? Now see here, we have sent out interstellar SOHOs to accurately analyse and measure the exact composition and density, refractive index and countless other properties of distant stellar atmospheres. We know to a high degree of accuracy just how much light from a more distant occulted star will be refractd and this just does not account for the observed shift. This clearly proves gravitational lensing, which of course proves beyond reasonable doubt that gravity interacts with light..................I think not.

Eric Von Danekin (sp) astounded a fact starved world with the cosmically important revelation that the hight of some Pyramid or other was some fraction or other of the distance from it to the Sun. Wow!
And these observed stellar shifts agree (within experemental limits of course) with relativity predictions of gravitational effect on light; so Q.E.D.?? talk about clutching at straws.:screwy:

[AGarvin]

Um, not quite correct, actually. Your assuming that the earth bound clock is an absolute frame of reference but relativity doesn't work that way. The west bound clock should gain time according to relativity not because it is moving west, but because its flightline (which just happens to be "west") is counteracting the rotation of the earth. In other words, the west bound clock is decelerating to a slower frame of reference relative to the earth bound clock. Since the earth bound clock is now moving faster than the westbound clock, it time dilates relative to the westbound clock. In other words, the west bound clock should be running faster (ie gaining time) than the earth bound clock.



Hmm, you might want to tell the US Department of Defence, since they did include error correction for time dilation in the global GPS satellite system. Maybe that's why my car has me turning into my neighbours drive ;).



Gravitational lensing is not refraction caused by light entering a different medium such as the atmospheres stars. It is simply light following a straight line through curved space .... according to General Relativity that is.

BTW, Eric Von Danekin also believes the earth was once visited by aliens. He also features under "Bad Astronomy".

Cheers,
Andrew.

[Starcrazzy]

yep..its the curvature of spacetime...spaceTIME..space and time...time and space....TIME and SPACE...its curved not flat...see...read up dudes...its all there for the learning....;)check out einsteins ring..http://www.universetoday.com/am/publish/perfect_einstein_ring.html
there ya have it..a picture of relativity..

[Doug]

Um, No, I am not assuming the earth bound clock is an absolute frame of reference at all; I thought I carefully avoided that pitfall. perhaps I was a bit vague. But since you raise the point, though the Earth bound clock is not a fixed frame of reference, relative to both air borne clocks it is. The very experemental data declares it to be so, because the data quoted says that one clock lost 59ns, RELATIVE to the ground based clock, and the westward flyer gained 273ns RELATIVE to that same Earth bound clock. The net difference between the two flyers would not be a true relativistic difference, but I suggest that the argument for the westbound time difference is rather hollow because:: for nominally half the flight, both clocks reverse their direction relative to the ground gripper clock. I think you have tried to nullify this point by the consideration of acceleration , but that acceleration is never constant thoughout the test, nor is it even in play for a statistically significant time. Sure from a 3 dimentional consideration things are not so straight forward, but for the sake of reasonable simplicity, let the east bound clock travel east relative to the ground clock, but only till it rounds the Earth. Now as the east bound clock rounds the Earth, still travelling eastward relative to the earth,relative to the ground clock it is in fact travelling westward, until it again rounds the Earth and still travelling Eastward, catches up to the ground clock, so sinse the data is referenced to the ground clock, some of its travel is Eastward but some (nominally half) of its travel relative to the ground clock is infact westward. The same situation exists though in reverse and slightly modified for the Westbound clock. Some of its travel is westward and some of it is eastward relative to the ground based clock. It is not that the Ground based clock is withinn a fixed frame, the data offered is relative to that ground clock forcing upon it the status of a fixed datum point relative to the three clock universe, else why compare the ground clock at all?
After all a net difference of about 330 seconds should be proof enough.........but wait, we can't do that because we need a fixed frame, an absolute against which to measure relatively speaking that is:rolleyes: . We need something to measure that is real. How big is the number i? Oh well if relativity doesn't work that way then maybe relativity doesn't really work in the really universe...who can say?



Hmmm I'll have to use simpler language I think.
The evidence for GL as I have read it was the measured shift in position of a close grazing or even occulted star as its light passed close to a large mass (a nearer star) This was the 'proof' of Gl that I first read of. This was the observation that I believe first gave GL its name. Since very little is known with any certainty about conditions close to distant stars, I consider it whistful thinking to claim proof of something when so little is really known or understood about the conditions prevailing. My reference to Eric Von was simply to point out the absolute ridiculousness of siezing on small values and claiming them as proof of something as Eric Von did, as many current researchers are still doing. In othere words, my thumb when multiplied by a suitable number would yield 93 million miles too; so what? That was the sort of nonesense Eric Von used to validate some of his myth. I was not holding Eric Von up as any sort of credible researcher.

Even the leading cosmologists can't agree on things relativistic. That should tell us something. They range from 'it was true along time ago in a galaxy far, far away', to 'it is only true for the first picosecond after the big bang..', to 'it isn't right now but it might be one day'. But of course openly refuting Einstein could see many a science world vendetta being issued against those scienific infidels.

But all this is not getting my pier poured.

I'm not saying Time dilation doesn't exist, I',m saying there is as yet no statistically compelling data that I am aware of to support the notion. Sending a clock across the solar system intercepting it six months after launch might tip the balance one way or the other, because gravitational influences and acceleration differentials would be a statistically small part of the overall time and velocity involved.

[AGarvin]

Whatever ... this will go around and around for ever and I have to say I'm over it.

Let's agree to disagree.

[Shawn]

Agreed:rofl:

[xelasnave]

When one day a space craft returns from "deep space" and there are a few headed out there ..which will return someday..when we get one back we can "date" materials on board and see if the effect is real or imagined. I have done no work on the experiment or have I read the Doctors book again as I said I would.. been working on other stuff though. But it seems all have been worn out by the exercise but have we not some wonderful thinkers to engage these issues. But in respect of my example of the ships nothing alters if you reduce the speeds or the distances the effect I decribe is present. I will do more when I can turn up one of the Dr's mind exercises and see if I can see it different.
alex

[g__day]

Time diliation is one of Einsteins more profund insights and thought experiements. It was so radical at the time he didn't get his Nobel prize for it but for photoelectric effect showing light can exhibit the properties of both a wave and a particle (at the same time!). Time diliation took decades more to start proving experimentally and prove it we certainly do every day.

In the air plane example its altitude reached (effecting gravity) and whether you are travel with or against the Earths movement in space around the Sun that causes the variance between the clocks.

Global positioning satellites have to correct for time dialition every day (increased distance from Earth lessens gravity speeding its time relative to us whilst their up to 30km/sec ortibal velocity slows time relative to us (but these time diliations are unequal in magintude causing a net need to correct about 25 microseconds a day)). Without correction we lose about 10 yards per day in accuracy!

Atomic colliders see great evidence of time dialiation. CERN often produces collisons that produce exotic particles that have very short lives before they decay - between 1 to 0.1 millionith of a second. Yet these particles can exist relative to us for up to 1000 times longer - almost milliseconds when they are travelling at 99.98% of lightspeed due to time diliation.

There is now a vast amount of supporting evidence of time diliation, its one of Einstein's best proved theories.

Relativity shows us that our frame of reference is critical to our sense of reality. There is no absolute time. It changes as you move, it changes if you are close or further away from a heavy mass. Relativity shows us that energy and matter are equivalent, not just convertable but equivalent. Meaning they are two directly linked attributes of a deeper underlying reality; like each is just one face of a coin or a dice we can interact with. Relativity links time and space with matter or energy in it. Space tells matter how to move and matter tells space how to curve. Gravity is not a force, it is the curvature or the underlying topology of spacetime itself.

[xelasnave]

Thanks G Day your confidence in the proposition is the most compeling I have met and very persuasive in changing my "beliefs". I have been making progress but it it difficult for me..its not that I dont read and read and have some small grasp but the more you look the more there is.. I have been months just looking at all the titles of different areas of maths.. the titles go on forever let alone the content.. it is intimidating but I go on. your input is very helpful to me and I sincerely thank you for taking the time. I understand space time does not see gravity as a force however I feel there must be a nuts and bolts machinery going on ..patricle to particle or energy to energy arrangement... I think you would say a quatum explanation is what I seek in addition.. my reasoning as to a pressure came from not finding a nuts and bolts explanation (not saying one is not available).
Thanks again
alex
alex

[g__day]

The trouble we have here is we experience a world every day at a level that makes us skeptical of the exotic. And when you consider the extremely large or small or energetic or short in time, well sorry but wierd just slips in.

Our everyday understanding doesn't help us intuit exotic extremes. So what is gravity given we really don't understand what is energy and matter and time at the extremes? Well my guess is all exotic models are possible until evidence rules them out. We can't connect the quantum to the relativistic yet, so until we can all our models will creak at the edges. Personally I think astronomy and/or high energy physics can provide that evidence, hence my interest in both fields!

[xelasnave]

Well I am working hard on a reconciliation of the two and everything else but it wont happen over night:lol: :lol: :lol: .
I can't help myself with the fasination and the questions even if none of the answers exsist in the world yet. I wish to assure you that I dont take myself too seriously in the gravity area as having the answers but I find having some questions is taking me forward. Thanks for your guidance.
alex