## Relativity?

How does science work? And what's all this about quantum mechanics?

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Noax
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### Re: Relativity?

ken wrote: Thu Feb 08, 2018 1:48 pmIs 'direction' the correct term to be using in relation to 'inertial frames' and 'time'?
No, the correct term is 'inertial reference frame' or IRF.
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?
Their respective frames are close enough that the clocks will stay synced for the duration of the example, to at least the precision expressed in the example. If the frames were so different, they not be able to publish in a book the distance to AC from here in that <implied> frame.
Noax wrote:Traveling at lightspeed is a mathematical singularity and not describable. It is not a technological limitation.
Are you saying that traveling at the speed of light is not a technological limitation.
You do this a lot, asking if I'm saying what you're quoting of me. Yes, I indeed wrote those words. Are you suspecting that somebody else put their own words in my posts?

Noax wrote:
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?
No, it is reasonably stationary in Earth's frame and stays synced to the precision we're considering.
How can any person KNOW what another clock is logging if they are, as you say, "in another frame"?
I don't say that. I say everything is in every frame being considered here. They're just stationary in one of those, and moving in the other frames, but 'in' them all.

Is this all just what you imagine would happen, or do you believe that this is what actually would happen, or is it both?
Sort of like asking if I stepped in front of the speeding bus and was struck by it, is being injured/killed what I imagine would happen, or what actually would happen. It seems both are the case. I imagine it that way, and it would actually happen.
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.
Clocks being synced in some frame means 1) that the clocks have reasonably similar velocity, and 2) they read the same value in the frame in question. No adjustment from this 'same value'.
If they don't have reasonably similar velocity, then they cannot be synced in this way. They can be synced instead to an event at which they are both present, meaning they read the same value at that event. Velocity matters not in this case.
So, ALL other frames in the Universe are the same, except for the "traveller's" frame, is that right?
No.
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?
The earth twin is not present at the u-turn event, and thus his age simultaneous with that event is frame dependent.
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?
The traveler has two different frames, the outbound one and the return one. Different answers in different frames. The traveler is younger (having aged 140 days vs. 8.6 years) when the meet again at Earth.
Are 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?
First, there is no such thing as a 'certain position'. There are just events. 'Positions' are a reference to 3D space, not 4D spacetime. The earth twin ages slower in both outbound and return frames (about 3.1 days each) since that twin is moving fast in both frames.
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?
He doesn't age at that event. Just different frames put a different Earth event simultaneous with the u-turn event. The traveler being in that frame or not does not cause this. This is what it means that different frames order events differently.

Suppose we wish to compare the altitude of two houses, on on the sea shore and the other on a mountain. Which is higher that the other depends on the arbitrary definition of which direction is 'up'. Yes, one direction is typically presumed, but actually any direction can be chosen, and if I consider a different direction to be 'up', then the house on the mountain can be the lower in altitude since the new direction orders the altitude of various points differently. No magic lifts the seaside house above the other. It is simply using a different designated direction that is 'up' and orders the altitude of different places differently.

Noax wrote:Of course. That's why the Earth twin ages only 3 days during each leg of the journey, in the frame of the traveler.
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?
It would be if I said that. I didn't.
So, in earth's frame the time the trip takes is 4.3 years, right?
The outbound trip does, yes.
This supposed "two digits of precision" between alpha centauri and the solar system is compared or relative to what exactly?
Compared to a greater precision.
Why would alpha centauri clock read 3 days short of 4.3 years at departure time, in the "traveller" frame?
That is the event which is simultaneous with the departure event in the outbound traveler frame.
And, what did the alpha centauri clock read at departure time, in the earth frame?
Zero.
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?
Frame dependent, but the same as each other in Earth/AC frame.
And, is that the exact same reading at departure time?
Frame dependent.
If so, and they are different from the "traveller" frame, at the departure time, then why so?
The Earth and AC clocks are not synced in the traveler frames. The 'why' is because different frames order events differently.
So, how "out of sync" now are earth clock and alpha centauri clock from each other, in earth/alpha centauri frame?
They stay in sync since they have negligibly different velocity.
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?
It was synced in Earth frame. It reads 4.3 years in the traveler frame. Different frames yield different answers.
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?
We've said all along that they're synced in Earth 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?
Not in traveler frame, which differs from the other two by .999c.
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?
Yes and yes.

Noax wrote:
And 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,
The AC clock is not present at that event, so is not synced to it. Instead it is synced to the Earth clock in the Earth frame. So in that Earth frame, yes, all 3 clocks read zero at that departure event. Without the frame specification, what the AC clock reads then is ambiguous.
and somehow during the journey the "traveller's" clock, earth's clock, and alpha centauri's clock only logged 75 hours, from "travellers" frame,
The traveler clock logs 70 days in the traveler 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?
In that AC frame, both AC clock and Earth clock read 4.3 years since they are synced in that frame and their clocks logged that much time during the trip, in said Earth/AC frame. Traveler clock reads 70 days, consistent with dilation of .999c over 4.3 years.
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?
Body aging is a physical process just like any clock. It is a clock in fact, just not a very high precision one. It's why I suggested using pregnant women, which are far higher precision clocks.
Also, if any of these clocks are different, then which one is RIGHT?
They're all right. None is defective.
And, where and when does the actual transition from one so called "frame" to another supposed "frame" take place?
The traveler transitions (accelerates) to being stationary in a different frame when he executes the u-turn, or when he stops at AC if he doesn't want to come back. That acceleration, or more precisely, the "moment of acceleration" is the key transition. Moment of acceleration is a lot like moment of inertial or like torque where the effect is multiplied by the distance in question. The two twins could accelerate equally, but the one with the greater moment will age less .

arth/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.
Frame dependent question as to which twin is moving, but to the 'traveler' who we say is taking the trip, it 'actually' takes 70 days.
What "frame" is the traveler in when they are at alpha centauri or earth?
Any of them. If he stops there, then he accelerates and becomes stationary in the AC frame.
And, how long did the trip take for this traveler when they are at alpha centauri or back on earth?
This question makes no sense. The traveler is in neither place when making the trip.
Was it you before who said some thing like that a human being can be "stationary" within a moving ship?
Probably me.
But 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?
Frame dependent.
Seems like you have many different frames, which are again all arbitrary, correct?
We've discussed the Earth/AC frame and the traveler frame, and perhaps the return frame. That's two or three at best that are relevant (not arbitrary) to the example.
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?
2-4 are the same. 5 is the return frame if we want to consider the round trip. None other is relevant to the example.
I just asked a plain, simple question, which then seems to be unable to be answered by some people.
There is no plain simple answer. What a clock reads simultaneous with and event with which it is not present is always a frame dependent answer, despite your desire for there to be a frame independent one.
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?
We've considered two or three, listed above.
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?
Simultaneously with AC (arrival or u-turn)event, Earth clock reads:
Earth/AC frame: 4.3 years.
Traveler (outbound) frame: 75 hours
Traveler return frame: 8.6 years minus 75 hours.
ken
Posts: 2075
Joined: Mon May 09, 2016 4:14 am

### Re: Relativity?

Noax wrote: Sun Dec 31, 2017 2:48 pm
davidm wrote: Fri Dec 29, 2017 4:41 pm
Noax wrote:Eternalism seems deterministic to me...
To me this is somewhat contestable as determinism seems to be an ambiguous concept in a block universe in which everything is simply given.
I will agree that it is contestable, but not because of free will considerations since the model takes no stance on it. It seems contestable because QM seems probabilistic. An objective view might resolve the conflict between those two,
A true objective view DOES resolve the alleged and supposed "conflict" between those two. In fact from a truly objective viewpoint ALL alleged and supposed "conflicts" are RESOLVED, and almost instantly I will remind. I have already explained, many times already, HOW to view from, and actually see, the truly objective point, (of view), that is if any one here has actually bothered to read and at least try to understand what I have been saying here.
Noax wrote: Sun Dec 31, 2017 2:48 pm but to discuss the topic on those terms, one must take the objective view on everything including a definition of what a person is,
Which, by the way, is a very extremely easy and simple thing to do, that is taking an objective view on every thing, and, defining what a 'person' actually IS. In fact ALL of you here once were taking an objective view, that is until you started believing that you already KNOW things.
Noax wrote: Sun Dec 31, 2017 2:48 pmand I suppose what the free part means with the will.
Also, very easy to define, and once defined correctly and accurately all other pieces of the puzzle start falling into place also. From which the big and true picture of Life is seen and understood.
Noax wrote: Sun Dec 31, 2017 2:48 pm The alternative is the subjective, common-language, naive view. Perfectly acceptable to discuss it in those terms, but then objective models must be left out of the discussion.
Must they?
Noax wrote: Sun Dec 31, 2017 2:48 pm Conflict arises only when objective and subjective terms are mixed, leading to inconsistencies that are not really there.
EXACTLY, and which is more or less what I have been saying all along.
Noax wrote: Sun Dec 31, 2017 2:48 pmSo for instance, one common definition of free will is "could have done otherwise". This leaves off completely what the subject is, the definition of a human. So the naive view is assumed since we all know the common concept of a person.
Do we?

I do NOT.

Maybe your assumed naive view is WRONG.

What do you think or believe is the so called "common concept" of a 'person'?

It will be interesting to see how far, or how close, that supposed "common concept" of a 'person' is to what an actual 'person' IS.
Noax wrote: Sun Dec 31, 2017 2:48 pm By that definition, and the use of the past tense, the turf is staked out. Is the past fixed but not the future? Why wasn't it stated as "can do otherwise". Probably because there is no "what was done" to contrast with "what should have been done". There has to be a made wrong choice to contrast with a better choice not having been made in the past, hence the necessity of defining things in past tense.
That "could have done otherwise" definition of 'free will' is so outdated, it seems laughable that human beings still use it, in the days when this is written. The "could have done otherwise" and the other just as ridiculous so called "definitions" of 'free will' IS the very reason WHY human beings of these times still see a CONFLICT.
Noax wrote: Sun Dec 31, 2017 2:48 pmAnyway, determinism is resisted in this view since the assumption of it conflicts with "could have done otherwise", but the model is the 3D naive view, so determinism is demonstrated false (by QM) in that mode, so they're partially safe so long as they don't look too close.
Another example of HOW and WHY human beings still view things as being "one OR the other". In these days human beings have still NOT learned HOW to view and see the truths and the falsehoods in ALL things, which ultimately shows there is NO conflict at all. EVERY thing is actually united, as One, and it is only human beings who MAKE and VIEW conflict. The, so called, "conflict", and "separation", that human beings view, see, and understand is ONLY BECAUSE of their own making.
Noax wrote: Sun Dec 31, 2017 2:48 pmAnother definition is "external volition", meaning a human is free willed only if the nature of a human is a physical avatar under remote control by a supernatural agent.
Another extremely outdated and wrong interpretation, well to Me anyway.
Noax wrote: Sun Dec 31, 2017 2:48 pm It suggests a falsification test for other views (demonstrate physics being overridden somewhere in the path of human choice), but they of course decline to make this simple demonstration of the view. We're poorly evolved for it, despite a way for it to work.
WHY do you human beings TRY TO fight for one side or the other?

Have you, human beings, NOT yet noticed that you have been doing this for thousands of centuries and have NOT progressed? You only fight for what you BELIEVE is correct. You do NOT actually fight for what IS actually right.

All of you are each, individually, trying to do is argue for your own already held points of views and beliefs. After centuries of human beings doing this the absolute fruitlessness of this would surely be easily recognizable by now.
Noax wrote: Sun Dec 31, 2017 2:48 pmIf we go with the objective view, we need an objective definition of all terms.
And there is certainly nothing wrong with that. Unless of course some one comes up with a sound, valid argument against this.

Perhaps a human becomes a worldline, but then "could have done otherwise" becomes worldline X could BE different worldline Y, which violates laws of identity.

Appears to be the usual type of deflective usage of words, when one is not actually sure of some thing.
Noax wrote: Sun Dec 31, 2017 2:48 pm So a different definition of free will is needed for the objective view.
The RIGHT definition is far more appropriate. But learning HOW to find the RIGHT definitions takes a bit of discipline, which sadly even the definition of that word gets used wrongly, by the older human beings.
Noax wrote: Sun Dec 31, 2017 2:48 pm My particular definition of a human doesn't 'do' anything at all, so there is nothing it can do otherwise, and it cannot objectively be held responsible for its actions.
But that was NOT a particular definition of 'human' at all. YOUR, so called, "particular definition" was of some thing else and NOT of 'human' at all. YOU just described the actions, or non-actions, of what a 'human' does or does not do. Or, are you saying that YOUR definition, of 'human', does NOT 'do' any thing at all?

If it is the latter, then it is a pretty useless definition, correct?
Noax wrote: Sun Dec 31, 2017 2:48 pm The objective view is almost worthless in the discussion then.
If that is what you believe, then so be it.
Noax wrote: Sun Dec 31, 2017 2:48 pmThe free-will thing seems to be important because of morals and responsibility for one's actions. But only the subjective view seems to be able to define the terms involved, so sure, there seems to be subjective morals and people are responsible for their actions,
Are ALL people responsible for their actions?

If that is what you think or believe is true, then sadly life on earth for human beings will continue on is detrimental path.
Noax wrote: Sun Dec 31, 2017 2:48 pm but none of these concepts seem to have objective equivalents.
That is because YOU are NOT looking the right way. And this is because YOU have NOT YET learned HOW to see things objectively YET.
Noax wrote: Sun Dec 31, 2017 2:48 pmConclusion: It is wrong to speak of eternalism or 4D models when discussing free will. It is mixing objective and subjective truths, leading to nonsense results.
Are there objective and subjective truths, to YOU? If so, then will you provide some examples?

Also, if YOU say there are objective truths, is that coming from YOUR own (and some others) subjective viewpoint, or from a truly objective viewpoint?

By the way I do NOT see any thing wrong with speaking of eternalism or 4 dimensional models when discussing free will, or any thing else, because they ALL fit perfectly together as One. But then again I see things far differently than most human beings.