Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Inertial frames are nothing more than a designation of a direction.
Is 'direction' the correct term to be using in relation to 'inertial frames' and 'time'? If yes, then how does different direction influence or change the outcome, and what do directions, themselves, have that changes the results or readings?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmSo, when you say earth's clock is synced with alpha centauri's clock, what do both clocks read at the event of syncing?
The exact same time? Or,
Different times?
The syncing is not an event since the clocks are not in each other's presence. Hence a frame needs to be selected. In that frame, the clocks read the same time. Since A-C is effectively the same frame as Earth (for purposes of this exercise), then they stay synced in that frame.
Is that in the IMAGINED exercise? Because for all intensive purposes alpha centauri and earth could NEVER stay synced because they are both moving at different speeds, unless of course some human being arbitrarily wants to make the choice that they are in the same frame?
If "empirical evidence" has verified that traveling at different speeds results in so called "time dilation", then there would NOT be two clocks ever remaining synced unless of course there are two things, with a clock each, that move at the exact same speed.
To say some thing like, X is "effectively" the same frame as Y (for the purpose of this exercise), without making the actual empirical observations of
what IS actually happening is to effectively predict, assume, or say what the actual outcome
will BE.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmNoax wrote:It is the frame in which the simultaneity is considered. It is not something that happens or is caused.
When is simultaneity considered?
???? Whenever you want. The ordering of events is frame dependent, but not dependent on when one considers them.
Are there actual real, different and separate 'frames', or do human beings just give separate labels to perceived different 'frames'?
There are actual real, different and separate 'speeds' at which objects, of which human bodies are one of, can travel. But are each of those multitude of differing levels of 'speed' really different 'frames'?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmIf it is NOT possible, then WHY do we talk about?
You're the one why always talks about future technology.
Do I?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Maybe they'll have something that accelerates all particles at once so the act is not even detectable to the traveler. Doing this without destruction of Earth (from the recoil) would be pretty awesome technology.
So would other things also be pretty awesome technology, but mentioning them here also would not really be on topic.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmWhen I question what would happen if, and only IF, a traveler could travel at the speed of light? I am almost inevitably told that that is impossible so there is no use in talking about it.
Traveling at lightspeed is a mathematical singularity and not describable.
Of course traveling at lightspeed is describable. Every thing is describable. That is why we have language and a word for absolutely every thing.
As for that being a mathematical singularity, human beings can make any thing into any thing just by perceiving and thinking.
The word 'singularity' is used by human beings some times in order to stop looking any further and to stop talking about and describing what is unimaginable to some of those human beings.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmIt is not a technological limitation.
Are you saying that traveling at the speed of light is not a technological limitation.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmNoax wrote:The frame defines which event is simultaneous with the departure event. That event on A-C happens to be 3 days short of time 4.3 years on their clock.
WHAT EVENT, and WHY does that event, on alpha centauri JUST HAPPEN TO BE 3 days short of time 4.3 years on "their" clock?
Also, who is "their"?
AC's clock. It doesn't 'happen to be'. It will read 4.3 years when at the arrival event, and that clock takes a 3 day journey in traveler frame, so I subtracted.
That clock is only presumed to "dilate" or slow down compared to earth's frame, right? Or, to you, is that not only presumed to be true, but IS an unambiguous fact, which can not be disputed?
HOW do you KNOW
what 'it will read', especially if the actual exercise has NOT yet been performed?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmIt's all just math.
AND the "maths" all depends on who is actually performing it.
NOT every one arrives at the same answers as you do.
Your answers appear to be contradictory and confusing. I am sure if you wrote the name of the actual thing instead of 'it' (will read) and described which event or what clock 'it' actually is instead of 'that' event, 'that' clock, or 'their' clock, then what you say would not be so confusing, to Me, and then I would not have to keep asking you clarifying questions.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmWhat do you mean by "negligible discrepancy"? In other words "by how much"?
Far less than the two-digit precision of our example.
What "two" clocks in earth frame if we synced "them" in that frame? Does "that" mean earth frame?
And, WHAT is "they" that stay synced?[/quote]
Your command of the English language is weak enough to render communication almost impossible. The two clocks are the AC one and the Earth one, as it was these two that you were asking about. 'that frame' means Earth frame, mentioned a few words earlier in the statement.[/quote]
Agreed. To you, it is solely I, whose command of the english language, which is rendering our communication almost impossible, right?
When you use 'it', 'their', 'that', et cetera how do I KNOW for sure WHAT you are actually referring to? Your use of 'it', 'their', et cetera is NOT always obvious what they are actually directed at or in relation to.
Or do you think and/or believe it would be better if I just always ASSUMED what you are actually talking about?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Noax wrote:He's moving in Earth frame. His clock logs less time in Earth frame. A clock that logs 70 days in 4.3 years is not able to stay synced.
And, according to you, earth's clock logs less time in "travelers" frame. A clock that logs 3 days in 70 days is not able to stay synced, is that right?
Yes.
But your maths does not seem to work.
Also, why do you keep repeating the exact same OBVIOUS things instead of just answering the question?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Noax wrote:Yes, but only in Earth/AC frame.
But why ONLY in earth/alpha centauri frame?
Why not in earth/"traveler" frame or in alpha centauri/earth frame?
Other frames order events differently.
How can any person KNOW what another clock is logging if they are, as you say, "in another frame"?
What do you mean by 'other frames' and '
order events differently'?
WHAT 'other' frames, and, WHAT 'order' are you talking about?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm How many frames are there, since both were present at that event?
Clocks were present at the event. Frames have no location.
Is this all just what you
imagine would happen, or do you believe that this is what
actually would happen, or is it both?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm If earth's clock and travelers clock were synced to zero at the departure event, then what was alpha centauri's clock synced to at the same departure event?
We said it was synced to the Earth clock in Earth frame.
Was alpha centauri clock synced the exact same, say for example as the exact same reading, or was alpha centauri clock adjusted in any other way from that reading.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm The AC clock was not present at the departure event.
Of course the alpha centauri clock was NOT present at the departure event. Alpha centauri is where the arrival event takes place and IS.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Noax wrote:The traveler clock changes 70 days between the two events because that's how much time elapses for the traveler.
But that is FROM the "travelers" frame. I am NOT asking about that. I am asking about WHY you can NOT give Me an answer as to what the "travelers" clock changes by between the two events from the earth's frame?
It changes by 70 days between those two events. It is not a frame dependent answer. So if you insist, it changes by 70 days in the Earth frame, or any other frame for that matter.
So, ALL other frames in the Universe are the same, except for the "traveller's" frame, is that right?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm
But how come now the "travelers" brother is older when you said before the time passed on the earth's clock would only be 6.2 days from the "travelers" frame, of which would be 140 days on the "travelers" clock? How could the one who, you say, aged less, from the "travelers" frame, now be the older of the two brothers?
This is the right question. There is a third frame now for the return trip, and in that frame, at the AC event where the U-turn takes place, the Earth twin is already 8.6 years older than he was at the departure event.
ALL questions are the right question.
However, you have missed the point. BEFORE you said, the clocks on earth would be logging slower from the "traveller's" frame, thus human beings and the "traveller's" brother would have aged "slower" because it was the "traveller's" frame that was "stationary" and the earth frame which was moving. But now you are saying when the u-turn takes place, the earth twin is already 8.6 years older than he was at the departure event. Now there is two questions, instead of just one;
1. Is the earth twin already 8.6 years at the u-turn event at alpha centauri or at the arrival event back on earth?
2. You said before the earth twin is younger than the "travelling" twin, from the "traveller's" frame, but now you are saying the the earth twin is older than the "travelling" twin, from the "traveler's" frame when the "travelling" twin is back on earth. So, which one is younger than the other when the "travelling" one is travelling AND when that one is back on earth at the arrival event?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAre you proposing some thing magical happened? Is the "travelers" frame magically completely erased and "come back" into earth's frame? Or, is there some purely logical reason for what happens here that you will now explain to us?
Different frames order events differently. At the AC event (the U-turn), the Earth twin's age is 3 days in the outbound frame but 3 days short of 8.6 years in the return frame. Not magic, just a conceptual change about what time on Earth is simultaneous with some distant event that is not on Earth. It is real enough that the twin back home really is 8.6 years older in that return frame than he is in the outbound frame.
Are you saying that when a "traveler" moves AWAY from a 'certain position' that the clocks at that 'certain position' change slower and that things age slower there, from the "traveller's" frame, but the exact opposite happens when the "traveller" moves TOWARDS the same 'certain position, that is to say that the clocks and ageing process speed up doubly?
If so, then why does the earth twin age by 8.6 years at the u-turn event at alpha centauri, which is said to be a distance of 4.3 years away, and which takes the "traveler" about 4.3 years to travel there in earth's frame?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAlso, is earth's clock and/or alpha centauri's clock dilated due to high speed in the traveler frame?
Of course. That's why the Earth twin ages only 3 days during each leg of the journey.
Did you not just say that the earth twin aged by 8.6 years, and in only one leg of the journey? If so, is this not contradictory?
Noax wrote: His clock logs only 70 days during the 4.3 year time it takes in that frame.
So, in earth's frame the time the trip takes is 4.3 years, right?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmIf so, is this 4.3 years the same length of time from alpha centauri's frame?
Yes, since they're effectively the same frame. We're assuming that AC is stationary relative to our system, which to well over 2 digits of precision, it is.
This supposed "two digits of precision" between alpha centauri and the solar system is compared or relative to what exactly?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAnd, what about from the moon's frame, jupiter's frame, this solar system's frame, the galaxy this solar system is in's frame, do they measure the time the trip took was about 4.3 years also? Or, do they read completely different readings, like maybe 70 or maybe 3.1 days too?
The frames of none of these things varies by anything near .001c, so no significant difference.
So, at what varied speed does any "significant" difference supposedly come in?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmWhat do you mean by 'we'?
You and I, since we decided that the two clocks would be synced in the Earth frame.
Remember, if, as you say, only 3.1 days pass, from travelers frame, on alpha centauri, then WHY would alpha centauri clocks read 4.3 years?
Because it already read 3 days short of that at departure time, in the traveler frame.
Did it? Why would alpha centauri clock read 3 days short of 4.3 years at departure time, in the "traveller" frame?
And, what did the alpha centauri clock read at departure time, in the earth frame?
What was the reading on the clock on alpha centauri and on the clock on earth, which 'we' decided would be synced in the earth frame?
And, is that the exact same reading at departure time? If so, and they are different from the "traveller" frame, at the departure time, then why so?
WHEN "traveler" is present at the event of arriving at alpha centauri what does the "traveler" read on the clock on alpha centauri?
1. 3.1 days
2. 70 days
3. 4.3 years
The third one.
So, what does alpha centauri's clock read when the so called "traveler" is present at the event of arrival on alpha centauri?
4.3 years.
Did you just NOT go through saying that earth clock and alpha centauri clock WERE synced at zero time at the departure event and stayed in sync?
No, I said they were synced in Earth/AC frame.[/quote]
So, how "out of sync" now are earth clock and alpha centauri clock from each other, in earth/alpha centauri frame?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmBut now are you suggesting that alpha centauri clock was NOT synced with earth's clock, as alpha centauri clock supposedly already read about 4.3 years at the departure time?
Different frame.
WHAT is 'different frame'? And, WHAT is THAT frame different from exactly?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmOr, did alpha centauri clock "jump" 4.3 years as soon as the "traveler" started moving or staying "stationary", however you want to word it?
It never jumped. No discontinuities.
You seem to like
alluding to things more than I do. The difference is I do not stop asking clarifying questions.
So, HOW did alpha centauri's clock end up being on 4.3 years at departure event, when it was synced with earth's clock at ZERO, at departure even?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmWhen you say "synced" what do you actually mean? If for example two clocks are "synced", do they read the exact same time, or, do they read different times, depending on their distance apart from each other, or, some thing else?
I said they were synced in some frame, which does not imply synced in another.
When did you say, they were synced in SOME frame, which I agree OBVIOUSLY does not imply synced in another?
Also, do you think it might speed things up if you said in WHAT frame exactly clocks were synced, instead of just alluding to SOME frame?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pm Synced means they read the same time.
Okay. So, earth's clock and alpha centauri's clock are synced at ZERO, at departure event, in earth's frame, alpha centauri's frame, and in "traveller's" frame, is this right or wrong?
If it is right, then great. If, however, it is wrong, will you explain what is right, and which you say 'we' have decided. Again, I will go along with whatever YOU want to sync the clocks at.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmHow can earth clock and alpha centauri's clock now be out of sync, when they were synced at departure event?
They're still synced in the Earth/AC frame in which they were originally synced.
So earth and alpha centauri's clocks are both are still synced in earth and alpha centauri's frame, is this right?
If yes, then that would mean that they both read 4.3 years, at arrival event, from earth and alpha centauri's frame, right?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAnd when you say both alpha centauri clock and earth clock have logged 75 hours, "in the traveler frame", is that while the "traveler" was in its own frame or when the "traveler" was present at the event of arrival on alpha centauri?
It was during time between the departure and arrival at AC events, in the traveler frame.
So, at departure event all three clocks, that is "traveller's" clock, earth's clock, and alpha centauri were synced at ZERO, and somehow during the journey the "traveller's" clock, earth's clock, and alpha centauri's clock only logged 75 hours, from "travellers" frame, but at arrival event on alpha centauri where "traveller" is now back in earth and alpha centauri's frame does the earth clock and alpha centauri's clock read 4.3 years and NOT 75 hours, and what does the "traveller's" clock read? Also, does the age of the body of the "traveller" correspond with the "traveller's" clock, whatever that is, and do the ages of the bodies on earth and at alpha centauri correspond with the clocks on earth and at alpha centauri?
Also, if any of these clocks are different, then which one is RIGHT?
And, where and when does the actual transition from one so called "frame" to another supposed "frame" take place?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmNoax wrote:They're still in sync in Earth/AC frame. Earth clock also reads 4.3 years in Earth frame, since the trip took that long.
But is that not a "frame dependent" answer?
It is. Earth/AC frame was specified.
Earth/alpha centauri frame was specified in relation to what earth clock reads, right? You also said, since the 'trip' took "
that long". But how long did the actual 'trip', itself, take? A 'trip' is usually in relation to the object, human being or thing, taking the trip and NOT usually relative to the departure point, destination point, nor any thing else.
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAre you now saying the trip actually took 4.3 years?
In Earth/AC frame, yes.
What "frame" is the traveler in when they are at alpha centauri or earth?
And, how long did the trip take for this traveler when they are at alpha centauri or back on earth?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAlso how can earth clock "ALSO" read 4.3 years when you said alpha centauri clock reads 3.1 days?
Different frames
But did we not agree that they were synced in the same earth/alpha centauri frame. What is the "different frame" now?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmAnd if the "stationary traveler" returns to earth, at the same "stationary speed" will the twin back home be older or younger?
If the traveler remains stationary, Earth is moving away and will not come back. He will not ever return there. Something has to accelerate.
Was it you before who said some thing like that a human being can be "stationary" within a moving ship?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmBut you also just said the twin back home had advanced by 4.3 years, so what did the earth clock advance by? 3 days or 4.3 years?
When the so called "traveler" is present at arrival event on alpha centauri what does earth clock read? 3 days or 4.3 years
Frame dependent questions.
Seems like you have many different frames, which are again all arbitrary, correct?
How about;
1. Traveler frame?
2. Earth frame?
3. Alpha centauri frame?
4. Earth/alpha centauri frame?
Is there any or many other frames that you can think of? If yes, how many and what are the name of some of them?
Noax wrote: ↑Sat Dec 30, 2017 7:16 pmWhat would the "traveler" when present at the arrival event see alpha centauri's clock reading?
4.3 years. I've answered this at least 3 times just in this post now.
And, what would the clock on earth be reading when the "traveler" is present at the arrival event on alpha centauri?
Frame dependent question.
[/quote]
I just asked a plain, simple question, which then seems to be unable to be answered by some people. Okay so you want/need A "frame", HOW MANY different frames are there when the so called "traveler" is present at the arrival event at alpha centauri?
Could you just provide the name for some of those "frames", and then just give the answer, to as many as those "frames" as you can?