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Author Topic: How does a 'field' become observer dependent?  (Read 200920 times)

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1250 on: 18/10/2014 09:50:32 »
Because we now (presumably:) agree on that the universe isn't made out of a 'container'. If it was you then could define a absolute frame to it, with that frame also being able to define it all as one  'field', expressing itself differently depending on 'density'. But it would also invalidate relativity, as well as giving us yet another question to answer, what would then be the 'outside'?
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1251 on: 18/10/2014 10:00:48 »
Would you want to state that a vacuum can't exist without a 'energy'? Think of Heisenberg's uncertainty principle, is that one related to a vacuum on its own, or is it, as 'temperature', related to restmass versus a vacuum? If you think of it the last way, what then about the Casimir effect? Is it about a vacuum, or about a combination of a vacuum and rest mass? How would you go about proving a 'energy' to the vacuum, not using rest mass?
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1252 on: 18/10/2014 10:02:38 »
The real point is simple. Do you think there can be a vacuum, without 'intrinsic energy'?
 

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Re: How does a 'field' become observer dependent?
« Reply #1253 on: 18/10/2014 10:11:03 »
From relativity, presuming Lorentz/Fitzgerald contraction as complementary expressions to the time dilations we observe, whatever distance you locally will measure always is relative 'motion', mass and energy. and the same goes for all other observers existing. Can you split a vacuum into pieces? How?

And if that vacuums 'distance' always is a local relation to your measurement?
What would that 'unified field' we assume look like?

Is there a global description of it, or will there only be local?
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1254 on: 18/10/2014 10:13:54 »
Because if you only have local definitions of it, then there is no global, more than causality, which we hopefully agreed on using a locally measurable limit set to 'c', which also contain the clock defining your arrow of time.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1255 on: 18/10/2014 10:15:22 »
So locally you're always moving in one direction, time wise. Called aging :)
 

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Re: How does a 'field' become observer dependent?
« Reply #1256 on: 18/10/2014 10:17:39 »
Locally there are two things that I see, accelerations and a arrow, that defines it.
Can you accelerate a vacuum? Or age it?
 

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Re: How does a 'field' become observer dependent?
« Reply #1257 on: 18/10/2014 10:26:29 »
From causality's point of view this universe is whatever can be causally connected through your measurements. If we take a hypothetical case where we have two observers of some third, in where one observe something happening which still haven't happened according to the other observer, do you think there could be a way for the one seeing it communicating this to the observer still not able to observe it.

What would that do to causality? Shouldn't be possible, should it?
So, causality and 'c' defining this universe.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #1258 on: 18/10/2014 10:52:05 »
Then again, if it was possible, what would it mean? Would you see it as a proof of a 'container universe', or would you then have to redefine it.
 

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Re: How does a 'field' become observer dependent?
« Reply #1259 on: 18/10/2014 16:22:31 »
Accelerations are indeed weird. Assume 'locality', then treat it as a 'local field', then define what a accelerations is intrinsically. You think you can? I'll give you a Nobel prize if you find a way to do it from locality.
 

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Re: How does a 'field' become observer dependent?
« Reply #1260 on: 18/10/2014 16:34:39 »
There are combinations existing to a locally defined reality. One is connections, defining a 'commonly existing seamless universe' that we expect ourselves to exist in. The other is the few definitions not resting on frames of reference, of which accelerations is one. I use 'c' but 'c' is, strictly defined, something defined over those frames of reference. The other ting I expect I can define is that arrow, but that one is also a result from 'c'.
 

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Re: How does a 'field' become observer dependent?
« Reply #1261 on: 18/10/2014 16:36:34 »
So? do accelerations exist in 'one frame of reference' or not? If they don't, then everything I define is a result of frames of reference, and 'locality' as such is the focus from where you define the rest.
 

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Re: How does a 'field' become observer dependent?
« Reply #1262 on: 18/10/2014 16:38:19 »
that doesn't make 'locality' non existent. But I lose any simple anchor to define it from. What is that clock?
 

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Re: How does a 'field' become observer dependent?
« Reply #1263 on: 18/10/2014 16:43:09 »
I will now give a proof of sorts for 'c'.

imagine that you shrink that two way communication (two way mirror) defining 'c'.
Do you expect it to differ as you shrink your experiment?
 

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Re: How does a 'field' become observer dependent?
« Reply #1264 on: 18/10/2014 16:44:33 »
Now use this type of defining, on accelerations.
Does it disappear?
 

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Re: How does a 'field' become observer dependent?
« Reply #1265 on: 18/10/2014 16:48:28 »
Gravity should disappear though, will a acceleration?
 

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Re: How does a 'field' become observer dependent?
« Reply #1266 on: 18/10/2014 16:50:01 »
Hopefully, it's not too boring, but one never knows :)
 

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Re: How does a 'field' become observer dependent?
« Reply #1267 on: 18/10/2014 17:24:41 »
So what differ gravity from a acceleration here?

Well, when you define gravity as disappearing 'magnifying' some area, you use an idea of what is measurable locally. And there, assuming you magnify a geodesic enough, the locally bent area won't be noticed, as you don't notice that earth is a sphere, walking. Will that be the same for accelerations?
 

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Re: How does a 'field' become observer dependent?
« Reply #1268 on: 18/10/2014 17:49:32 »
What type of gravitational field are acting on you in a uniformly, constantly accelerating rocket, at one gravity? Is it local or do you expect it to exist outside the frame of reference joining you with the rocket? It's local, don't you agree? The far away observer, or 'near', will not notice it as 'gravity'. Use this on the gravity acting on you here. Is it so that the near observer won't notice it?

Here you get two choices, either you choose the equivalence principle, that one is strictly local. Or you argue from a container model in where the gravity found locally in that rocket differ from what you would expect the 'near' observer to define (Earth).
 

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Re: How does a 'field' become observer dependent?
« Reply #1269 on: 18/10/2014 17:51:09 »
so which one is right? Well, what do you think of repeatable experiments? And constants?
 

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Re: How does a 'field' become observer dependent?
« Reply #1270 on: 18/10/2014 18:31:42 »
And yes, I think you can define a vacuum without a 'intrinsic energy' as just a 'distance', locally measured.
 

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Re: How does a 'field' become observer dependent?
« Reply #1271 on: 18/10/2014 18:32:43 »
I would prefer not to use that one though, but I still think it must exist.
 

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Re: How does a 'field' become observer dependent?
« Reply #1272 on: 18/10/2014 18:33:45 »
It's the 'property' of a vacuum.
 

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Re: How does a 'field' become observer dependent?
« Reply #1273 on: 18/10/2014 18:35:01 »
The opposite proposition is that a vacuum doesn't exist.
It's a 'field'.
 

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Re: How does a 'field' become observer dependent?
« Reply #1274 on: 18/10/2014 18:39:30 »
That would then reduce this world to one thing, no opposites, no ideas of yin and yang, and what symmetries should be from such a proposition I don't know? What is a symmetry? What is a opposite? You will have to rewrite history for it.
 

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Re: How does a 'field' become observer dependent?
« Reply #1274 on: 18/10/2014 18:39:30 »

 

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