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Author Topic: How does a 'field' become observer dependent?  (Read 201484 times)

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #100 on: 20/11/2013 16:49:03 »
So, what would I like to define as a single 'frame of reference'? Well, we need super imposing, and that is entirely possible using quantum logic. We need a limit, and that is Plank scale to me. So? What about a 'point particle' what about 'excitations in a field'?

Gotta like decoherence.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #101 on: 20/11/2013 16:55:00 »
Doesn't mean 'bits' though, means what it say, 'limit'. But that is from where our .. local .. principles and constants should come as I think. Defining it through 'scales'. Although you naturally are free to define this as the 'bits', creating a universe, you still have to explain from where the constants and principles come. Either you turn it into a cat biting its tail, making some circular logic, or you prefer a linear logic, as a beginning and a end. Or you might prefer quantum logic, in where it all exist, outside a arrow. The last one demands something existing, past Planck scale, as I read it.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #102 on: 24/11/2013 16:49:07 »
What would gravity be from a purely local point of view? Similar to what a expansion might be seen as, locally described? Can I describe a expansion as a 'upwelling', of a added distance, constantly creating in all points? And then gravity as it exist for me, standing on matter, as a 'down welling'? Weird thought, isn't it :)

Gravity is related to matter, and 'energy', as well as accelerations/decelerations, being two sides of a same coin. Does a expansion automatically bring with it a added energy equilibrium? If now a 'vacuum' contain a energy. It must, if that is true. Otherwise the 'energy' of that 'universal container' should dilute, and what would that do to the conservation laws?
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #103 on: 24/11/2013 16:55:44 »
You can have such a universe, in where a expansion express itself in all points, as long as we have a mechanism for keeping particles 'together'. Think of buoys in a pond, getting filled up with water and assume 'gravity' (as well as the microscopic 'forces') being the security net, updated at 'c'.

It's 'c' that's important here I think. The 'speed' of communication.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #104 on: 24/11/2013 18:26:02 »
Gravity is always pointing inwards. Plank scale is always as close to you, no matter from where you choose to scale it down. Take a sphere of matter, reduce it to plank scale, or at least as far as you can get. Not 'shrinking' it, just subtracting particles from it. Will it still have a gravity? And what way would that gravity point? Assume it existing in a 'flat space'.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #105 on: 24/11/2013 19:36:03 »
"The gravitational constant (G), first estimated by Isaac Newton and also known as Newton's constant, describes the strength of the gravitational pull that bodies exert on each other. " Then we have "the acceleration due to gravity at the Earth’s surface. The symbol for the first is G (big G), and the second g (little g)."

The first. G, is defined as a constant, although hard to pinpoint experimentally.

"The first experiment to measure Big G was conducted in 1798 by British scientist Henry Cavendish. He set up a clever device in which a dumbbell-like object with two lead balls on either end was suspended by a wire. Another dumbbell was placed so that its balls were near the two spheres. The gravitational attraction between the two sets of balls caused the dumbbell on the wire to twist. A mirror on the wire reflected some candlelight, creating a beam of light that allowed Cavendish to carefully monitor exactly how much the wire rotated. His experiment produced a value for G of 6.74 × 10−11 m3⁄kg s2.

Since then there have been dozens of experiments to measure G, producing a modern estimate of 6.67384 × 10−11 m3⁄kg s2 – not far from the 200-plus-year-old experiment’s results.

“These days, we use a laser light that gets measured by an LED, but it’s not really so different from what Cavendish did,” said physicist Harold Parks of Sandia National Laboratories in Albuquerque, New Mexico, co-author of the paper with the new Big G value that appears Sept. 5 in Physical Review Letters.

The team, led by Terry Quinn, the former director of the International Bureau of Weights and Measures in France, used an updated version of Cavendish’s setup for one experiment. But they conducted an additional experiment, using a servo to counteract the twisting of the wire and figuring out the gravitational constant based on the voltage required to keep their apparatus from moving. Taken together, their tests yielded a new G value of 6.67545 × 10−11 m3⁄kg s2, which is higher than the current accepted value by about 240 parts per million. It may not seem like a big deal, but a constant should be constant and physicists would like to know that they have it finally figured out.

The main problem here is that gravity is an extremely weak force, more than 40 orders of magnitude weaker than that other familiar daily force, electromagnetism. When you reach over and pick up a pen from your desk, the electrostatic forces in your hand (which allow you to hold solid objects) are able to quite easily overcome the gravitational force of the entire Earth on that pen." http://www.wired.com/wiredscience/2013/09/high-gravitational-constant/
« Last Edit: 24/11/2013 19:38:35 by yor_on »
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #106 on: 24/11/2013 19:43:51 »
'c' is a local constant that you can split all the way to Planck scale. One Planck length, being the smallest meaningful distance light are presumed to propagate, in one Planck time. You can do the same with a local arrow, assuming it equivalent to 'c'. So what about gravity?
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #107 on: 24/11/2013 20:28:34 »
A mix of quotations.

"According to modern physics field theories, each of the four basic interactions (a better term than 'force') is mediated by a type of particle:

The strong (nuclear) interaction is carried by gluons. (This is the interaction that holds together the particles in the nuclei of atoms.)  An attractive short range 'force' between particles like protons and neutrons

The electromagnetic interaction is carried by photons. (This is the interaction responsible for all electrical and magnetic phenomena.)  An attractive or repulsive long range 'force' between two objects with charge

The weak (nuclear) interaction is carried by weak bosons. (This is the interaction that governs certain radioactive decays, such as beta decay.) A short range 'force'.

The gravitational interaction is carried by gravitons. (This, of course, is the interaction that gives rise to the familiar pull of gravity.) An attractive long range 'force' between objects with mass. "

Photons have an energy, and so a equivalence to mass. They are point particles though, bosons, not taking up place. There is nothing I know forbidding you to superimpose all photons existing, at any given instant. So it is rather meaningless, as it seems to me, using those as some smallest definers of that constant? As long as we use (Planck) scaling that is, passing that it may become meaningful in some other way. Try this one http://plato.stanford.edu/entries/equivME/ for some thoughts on mass and energy.
« Last Edit: 24/11/2013 20:31:06 by yor_on »
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #108 on: 24/11/2013 21:00:10 »
So what are 'point particles', having no measurable size, as far as science know today? Some quotes on it, and one link :)

"A point particle, also known as a point mass, is an idealized object which has mass but no extent in space. An object which does have extent in space can be considered to consist of an infinite set of point masses. If the object neither rotates nor deforms, every point mass making up the object undergoes the same motion (or lack of motion) that every other point undergoes. Hence, laws of motion that apply to a point mass can be applied to an object that neither rotates nor deforms. In the case of objects that do rotate and deform, laws of motion that apply to a point mass can be used to characterize the motion of the center of mass of the object."

"The quarks, leptons and bosons of the Standard Model are point-like particles. Every other subatomic particle you’ve heard of is an extended particle. The most familiar are the protons and neutrons that make up the nucleus of an atom, but there are many others—pions, kaons, Lambda particles, omegas and lots more. The defining feature of these kinds of particles is that they have a reasonably measurable size (which happens to be about the size of a proton)."

"A lepton is an elementary, spin-1⁄2 particle that does not undergo strong interactions, but is subject to the Pauli exclusion principle. The best known of all leptons is the electron, which governs nearly all of chemistry as it is found in atoms and is directly tied to all chemical properties.

Two main classes of leptons exist: charged leptons (also known as the electron-like leptons), and neutral leptons (better known as neutrinos). Charged leptons can combine with other particles to form various composite particles such as atoms and positronium, while neutrinos rarely interact with anything, and are consequently rarely observed.

There are six types of leptons, known as flavours, forming three generations. The first generation is the electronic leptons, comprising the electron (e−) and electron neutrino (νe); the second is the muonic leptons, comprising the muon (μ−) and muon neutrino (νμ); and the third is the tauonic leptons, comprising the tau (τ−) and the tau neutrino (ντ).

Electrons have the least mass of all the charged leptons. The heavier muons and taus will rapidly change into electrons through a process of particle decay: the transformation from a higher mass state to a lower mass state. Thus electrons are stable and the most common charged lepton in the universe, whereas muons and taus can only be produced in high energy collisions (such as those involving cosmic rays and those carried out in particle accelerators)."

The 'point' with 'point particles' is that they can be seen as having a field, interacting with the energy of the vacuum, aka 'virtual particles'.

"Let’s start with the easiest point-like particle we know, the electron. Assume it has zero size. Although we know that the quantum realm differs from the familiar world, in which things are measured in inches and feet, we can still get a reasonable mental image of what happens as we imagine looking at an electron with a perfect microscope. To begin with, since it has zero size, you can never actually see the electron itself.

However, you notice the electron does have an electric charge, and that sets up an electric field around it. That’s the first crucial point. The second crucial point is an idea called the quantum foam, which refers to the fact that empty space isn’t actually empty. Matter and antimatter particles appear and disappear with utter abandon, willfully flouting what seems like a principle of common sense. Empty space is actually pretty complicated.

Now if you combine those two ideas—that there is an electric field and that space consists of a writhing, bubbling mix of particles—then you can imagine what a point particle is like. At a large distance from the particle, its electric field is weak and doesn’t much affect the quantum foam. However, as you get closer to the point particle, the field becomes stronger. The stronger field affects the ephemeral virtual particles to a greater and greater degree, eventually lining up other particles with its point particle. (For example, the field of a positively charged point-like particle will push away other positive particles and hold negative particles close.)

Thus if you collide two point-like particles, while the two particles might never actually collide, the cloud of particles surrounding them will likely interact. The point-like particle is the mathematical abstraction at the center of the particle, but the extended field in essence makes even a point particle not so point-like." https://www.fnal.gov/pub/today/archive/archive_2013/today13-02-15_NutshellReadMore.html
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #109 on: 24/11/2013 21:05:42 »
No size right, but still of defined although fuzzy positions, and furthermore the orbital of a electron in a atom, is not fuzzy, as I gather.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #110 on: 24/11/2013 21:08:46 »
Would you say that a atom needs its electrons?
 

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Re: How does a 'field' become observer dependent?
« Reply #111 on: 06/12/2013 10:00:01 »
A field :)

Assume light to be non propagating. Then assume that what we measure as lights speed in a vacuum is excitations defined by relations, creating a pattern 'propagating'. You can also split it into two parts as I think, one 'static' and that is a field, then a arrow that creates change. Also you need to assume that 'location is all', meaning that observer dependencies is a matter measuring over frames of reference, with the constants we find to exist, existing locally purely. And that fits the way gravity behaves too as I think, as if gravity was a 'down welling' in each point, somewhat like gravity has a direction, slope on slope inwards, towards some 'center'. But what about matter? What about about me, moving my hand? Or my nails growing? How would such a universe 'remember' the way we transform? and how would it consistently keep us 'together'

Two parts. A static 'field' with a observer dependent arrow. And then matter, the universe, and 'motion'.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #112 on: 06/12/2013 10:17:24 »
Because I define a 'clock' equivalent to 'c', they both become 'constants'. And as all 'constants' are locally defined I would expect that what really is non illusionary is just those '(locally definable) points'. They are what's not 'observer dependent'.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #113 on: 10/12/2013 13:06:19 »
How about this then?

Think of the universe as a plane, then gravity as something coming to existence (as locally defined) interacting with that plane, acting perpendicular to it?

If I would adopt that view, then 'gravity' is existent even when not measurable, but as a 'property' of a SpaceTime, which indeed would make some sense to me :)
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #114 on: 10/12/2013 13:25:35 »
Although, if you as me want to define it from points, a plane would just be a conceptual description. That as this 'plane' you might measure on, must be observer dependent, so creating that same confusion as the idea of a 'container universe' of four dimensions. To make it fit my weird thoughts :) You need to define it purely locally, to get to what a constant, principles and a 'non observer dependent' reality must be, well, as it seems to me now at least?
=

That would mean a universe's 'properties', naturally.
« Last Edit: 10/12/2013 13:32:04 by yor_on »
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #115 on: 10/12/2013 14:11:04 »
And if you don't use a plane, then this 'perpendicular' definition becomes wrong, although still usable as an idea of something existing as defined over frames of reference, also assuming a universe to be a projection, although 'real enough' for us measuring 'inside' it.  With a point particle, assuming it to exist and to interact with 'gravity', the direction becomes toward some 'center', does it not? If assuming three 'dimensions' and a arrow for it to exist in. Then again, the 'point particle' itself might very well be a dimension less quality/property of a SpaceTime, in which case we might want to keep the idea of a 'perpendicular' direction?
 

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Re: How does a 'field' become observer dependent?
« Reply #116 on: 10/12/2013 14:19:47 »
Because, assuming a point particle to have a dimension less quality/property, also defining a universe's properties from strict local definitions, it doesn't make a lot of sense defining it to have three dimensions, does it? The only way you can justify that sort of definition is when you place the point particle inside a three-dimensional universe (and a arrow, to measure in it).

What we then might get to is something where a 'direction' comes from interactions.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #117 on: 10/12/2013 14:21:20 »
And where interactions defines 'dimensions, distances and time'.

Your local ruler and clock.
 

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Re: How does a 'field' become observer dependent?
« Reply #118 on: 10/12/2013 14:24:12 »
That as when you measure on a universe, you do so over frames of reference. But locally, always locally.
 

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Re: How does a 'field' become observer dependent?
« Reply #119 on: 10/12/2013 14:26:12 »
So your arrow would be a 'constant', as 'c', and your local 'ruler' should then also be a constant, as it seems to me, all from a strictly local definition.
 

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Re: How does a 'field' become observer dependent?
« Reply #120 on: 10/12/2013 14:32:05 »
In fact, that is the way it must be, to get to a repeatable experiment. We need some properties (laws) to be the same, no matter where we measure from. And those 'properties' allowing us to find those laws, must then to a high degree be considered 'equivalent'. Otherwise we can't have a universe as we define it today.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #121 on: 10/12/2013 14:34:23 »
From a 'global' point of view I can describe a multi verse, as it is observer dependent. From a 'local' point of view, we share the exact same constants, principles, properties, etc etc.
=

That should be read as a your 'multi verse' existing, as defined by your measurements, when compared to some other observers measurements, ignoring Lorentz transformations. You can't introduce a Lorentz transformation without moving the universe from measurements, into conceptual 'space'. Realistically, your measurements define your environment, and what will happen, to you that is :) then we also have the possibility of fitting your measurement to mine versus a Lorentz transformation.

The last is what defines our universe's causality. If there was no causality, a Lorentz transformation should not exist.
« Last Edit: 10/12/2013 14:42:20 by yor_on »
 

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Re: How does a 'field' become observer dependent?
« Reply #122 on: 10/12/2013 14:46:48 »
Causality is unavoidable, I think? As long as we have the same local properties definable in all 'points/observers'. Or can you construct a universe in where we all locally share the same principles, 'constants/properties', equivalently. To then come to a (global description of a) universe without a causality of some kind existing?
« Last Edit: 10/12/2013 14:48:19 by yor_on »
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #123 on: 14/12/2013 17:46:09 »
I'm not especially excited over the idea that 'all time' co-exists. You can theorize that it does, Using those locally defined 'time slices' and then imagine that you 'instantly' could see the whole SpaceTime loaf, depending on motion, direction and mass (energy). It's just not true, causality won't allow it. It seems as some really smart people have allowed themselves to be seduced by its novelty. It's like the idea of the moon only existing, as you observe it, Einstein doubted that one with very good reason, the moon will be there.

And I don't need entropy for defining this. I just need a locally measured 'c', and assuming a equivalent 'clock'.

'c' is not relative. It's only relative when you think in terms of a 'container universe'. Locally measured you can prove that your local time never change, locally you can join any frame of reference, finding its 'time' to be yours too, and no experiment you can imagine locally will prove this wrong.
 

Offline yor_on

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Re: How does a 'field' become observer dependent?
« Reply #124 on: 14/12/2013 17:53:29 »
That doesn't state that there isn't a possibility of something containing a whole SpaceTime. Scaling SpaceTime down to Planck scale, gravity disappear. Isn't that a accepted fact? And so does 'c', and if I'm right so should a local arrow. But you measuring will have a clock ticking beside you, so in your measurement a arrow must be involved. It's very hard to imagine a way to test 'singular frames of reference' in themselves. We always test locally, over frames of reference.
 

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Re: How does a 'field' become observer dependent?
« Reply #124 on: 14/12/2013 17:53:29 »

 

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