The Naked Scientists

The Naked Scientists Forum

Author Topic: An essay in futility, too long to read :)  (Read 280885 times)

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #450 on: 11/12/2011 07:55:46 »
This is a sidetrack.

I've noticed many wanting to put GR into question. Finding blue and red-shift speculative, and the groundwork describing GR to be questionable. Some even going so far as wanting to in-cooperate their 'pet theories' in the wiki:s describing the experiments validating it (GR).

So I though it could be cool to see how it hold up to scrutiny.

The Confrontation between General Relativity and Experiment. and Testing General Relativity with Pulsar Timing.

As far as I can see it works as expected.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #451 on: 11/12/2011 08:23:26 »
Heh, maybe not a side track at all. I do like this :)

"In 2005, on the 100th anniversary of the introduction of special relativity, one might ask “what is there to test?”. Special relativity has been so thoroughly integrated into the fabric of modern physics that its validity is rarely challenged, except by cranks and crackpots. It is ironic then, that during the past several years, a vigorous theoretical and experimental effort has been launched, on an international scale, to find violations of special relativity.

The motivation for this effort is not a desire to repudiate Einstein, but to look for evidence of new physics “beyond” Einstein, such as apparent violations of Lorentz invariance that might result from certain models of quantum gravity. Quantum gravity asserts that there is a fundamental length scale given by the Planck length.. 




But since length is not an invariant quantity (Lorentz–FitzGerald contraction), then there could be a violation of Lorentz invariance at some level in quantum gravity. In brane world scenarios, while physics may be locally Lorentz invariant in the higher dimensional world, the confinement of the interactions of normal physics to our four-dimensional “brane” could induce apparent Lorentz violating effects. And in models such as string theory, the presence of additional scalar, vector, and tensor long-range fields that couple to matter of the standard model could induce effective violations of Lorentz symmetry."

As for the theoretical aspects of different definitions I offer no insights, but it's very nice realizing that I'm not the only one wondering where those 'contractions' end, and what to make of it. Though I included HUP there, at a greater scale than Planck length, as creating a possible definition of a background invariant 'smoothness' over Planck scale.

Not that I can know, and it it's highly speculative, especially as it depends on how you think of what HUP tells you about itself. To me it's talking about indeterminacy, 'defined' at your choice of measurement, which looking at it my way leaves what 'background' there is 'indeterministic' as it only will answer to what you measure, and what way you choose to get that answer.

It's about how real 'reality' is, sort of :)
Kind'a luve it.

And it's quite nice to me as it allow uncertainty at a very basic level, in some intricately weird way even representing a idea of 'free will' to me. Even though I have difficulties defining exactly what I mean there, there are many interpretations possible.
=

(Couldn't find the right mathematical expression so made a *.jpg instead. Ouch, can't center the jpg without the rest of the text becoming centered too. Ah well..)
« Last Edit: 11/12/2011 08:48:15 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #452 on: 14/12/2011 02:40:50 »
One way measuring of light?

I've been thinking of it, wondering what would happen if you take two points A and B. then measure the 'gravity' at those points and all points in between. As I expect it to be related to Planck scale, meaning that I expect that to be the smallest 'frame of reference' you can find, using 'clocks' as your definition of where one 'frame of reference' starts and the next ends.

Even as we don't have clocks that accurate we can still test it. And doing so will give us a 'gravity map' between A and B. Then one send a light pulse from A (source) to B (detector) using B:s local clock, and compensate for the gravity found in between. If that works out to be close to 'c', then we have a possible one way definition of lights speed in a vacuum, possibly :)

If it doesn't work out then there should be something wrong in my suggestion, alternatively something not considered like densities etc.

But what it would do is to test if Plank size could be defined as a 'frame of reference' relative other 'frames' using 'ideal clocks' as the definition.

Another thing that's started to nag me is how to define a speed/velocity. As all frames of reference is relative in the real world. Meaning that you conceptually can define a inertial frame, but that I do not know of any that will hold up to proof, measuring directly?

But we all expect us able to send some particle away, in the LHC for example, closing in on the speed of light in a vacuum. How do I define it? From what? Can't use the stars blue shift in front of me, can't use the CBR, can't use Earth? But we can accelerate particles, and we do define them as relativistically moving?

But relative what frame, and if I change that frame to another uniformly moving?
Maybe those two ideas are related? I need to see this a lot clearer.
« Last Edit: 14/12/2011 02:42:40 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #453 on: 14/12/2011 02:58:48 »
You can turn my reasoning around and point out that in a classical two way experiment all 'frames of reference' will give me 'c', which I also expect it to do. But the idea of a 'speed' then becomes meaningless to me, although the idea of a 'constant' becomes all important.

And using 'c' as a constant as well as the 'clock rate' related to my and yours local 'arrow of time', the same for us all as proven if we 'join up' together, makes then a lot more sense than discussing it in form of 'speeds'.

But, as a 'speed' is a definition relative a clock and a distance?

The 'clock' I think I understand, but 'distance'?



 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #454 on: 14/12/2011 09:15:49 »
I know, slightly mental maybe :)

But this is the way I think about it. All uniform motion inside a black box/room scenario is interchangeably 'at rest'. No matter your definition of your possible 'velocity/speed'. From that I draw the conclusion that it is true that they are interchangeable. So a 'velocity/speed' is already there doubtful as a objective definition, or, not correctly defined.

And then we have those Lorentz/Fitzgerald contractions, done the Einstein way. I see them as true statements, constant mirrors to a time dilation. But it's a very tricky one, and I can't be totally sure. Also I expect HUP to create a 'fogginess' at a quantum level, as atom scale, or maybe even larger? I can't be sure there either :)

Never the less, both question distances, although the later only at that 'conceptual plane' comparing them. That as you locally always will be able to define a distance, using your ruler and your clock.


But you know what :)
I find the idea of those black box scenarios pretty convincing in a intuitive way. So to me that is something truly diffuse, what a distance really mean.


Assume that there is a Higgs ocean.
It still doesn't explain a Lorentz/Fitzgerald contraction.
And it does not answer where those 'Higgs bosons' went in a contraction, unless you define it as a 'field'. If you define it as waves, do they compress?
« Last Edit: 14/12/2011 10:01:03 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #455 on: 15/12/2011 10:54:32 »
Remember that using 'locality' relative your clock, distance will always be unambiguous.

It's about what I call 'conceptuality'. We live inside a conceptual world, we define it through a 'now' a 'past' and a 'future'. Every experiment, every thought, can be defined to the 'past', in that as it becomes your outcome it's already passed, using a 'arrow of time' defining the causality chain.

Everything we do involve this arrow. To argue about what it consist of is interesting, but it will still come down to the same experience for you. The 'past', 'now', and the 'future'. I define it as equivalent to 'c', using 'c' split up, as exactly as we can, becoming the local rate of your clock.

Lights smallest 'propagation', at one Plank length in one Plank time becoming the other 'constant' to me. Defining a smallest 'beat' of your local 'clock'. Also defining the smallest 'length' that will be meaningful inside SpaceTime.

NIST shows us that you can split Earth into 'frames of reference' time dilated relative each other. If that is a truth, then a Lorentz contraction should be there too? At least as I expect it to be. HUP seems, to me, to be what allows this contraction to be existent at that very small plane of existence.

You might consider it as that without HUP the chances of me arguing here would not exist. As our coherence macroscopically couldn't be. But it's a very long shot that one, although I still see HUP as the main reason allowing particles to 'join up' other definitions of HUP exist. Most automatically seeming to assume that at least some parameters of a particle always 'exist'. And that one goes back to the way we experience matter macroscopically.

To see my points you better consider your 'reality' as somewhat of the 'flavor of the game', but not the game itself.

But we still refer to each other and the universe each one of us percieve, as being the same, don't we? And that must be radiation communicating that impression to each one of us.

Radiation is a 'constant', not a 'speed', defining the limits for how we can exchange meaningful information inside SpaceTime. And SpaceTime then becomes a 'density' in my eyes, encased in the conservation laws, gravity and 'c'.
« Last Edit: 15/12/2011 11:36:28 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #456 on: 15/12/2011 11:05:41 »
If radiation is a constant, then using the idea of speed becomes wrong. Not in that it doesn't exist for us, but in that it can't be the complete description of how SpaceTime operates. That allows my idea of it 'ticking' from locality. If that is the way it would work at 'another plane', then the definitions we use is incomplete. And if so the description of a 'propagation of light' gets an added implication, in that it also could be seen as something not 'propagating' at all.

That might seem to solve some problems, but also creates new. If light doesn't 'propagate', what holds the 'beat' it show us? I call it the 'rules of the game' and, in fact, the same question can be stated for the light 'propagating'. Although, not in the exact same way.

What creates the 'reality' we see I expect to be our 'constants', which then becomes the limits defining SpaceTime.
« Last Edit: 15/12/2011 11:53:55 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #457 on: 15/12/2011 11:16:13 »
And that becomes my number space, in where nothing 'moves'. The 'motion' is our interpretation of those numbers changing. Each one of us having a unique definition of its change, hold together through 'c'. That constant then becoming what creates the common 'SpaceTime' Einstein defined. I don't think my interpretation is that different from his, he called SpaceTime a 'illusion' more than once, and I agree.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #458 on: 15/12/2011 12:08:11 »
So what creates constants? Do they create each other?

I think about a smallest definition of something as already being in three 'dimensions'. I don't expect it to be 'one dimensionally' connected inside SpaceTime. Outside SpaceTime it might be another description though.

But the point I want to make is that as soon as we can 'touch it' as in it being 'there', taking a place, then according to the Pauli exclusion principle it is defined in a three dimensional space as I see it. 
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #459 on: 15/12/2011 12:11:22 »
And looking at it from Einsteins point of view. Defined in a four dimensional SpaceTime. Those of you finding my ideas weird really need to consider what you think of Einsteins :) Because most of you then missed what he was taking about, A four dimensional reality.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
An essay in futility, too long to read :)
« Reply #460 on: 15/12/2011 12:53:09 »
You can look at it different ways, as it seems to me. the first being that we through 'scales' then can dissect 'SpaceTime', slicing it up into singular dimensions. Or the one I present in where 'SpaceTime' will hold until its bare limits are meet.

In fact, looking at it through Einsteins eyes I guess that you could describe the whole of SpaceTime as being one 'four-dimensional' thingie. Getting different positional values depending on each 'observers' mass/acceleration, 'energy' and 'relative motion'. But if considered a common SpaceTime, all being one expression, expressed in Lorentz transformations.
=

But scales exist, just as distances do, and the arrow. And using scaling we can magnify SpaceTime, down to that very quantum realm where we find it to 'break down'. Down there not much seems to be as above. Matter becomes a diffuse description of 'forces' creating and binding 'particles' into molecules, gravity seems to disappear or at least becomes very hard to find.
« Last Edit: 15/12/2011 13:02:24 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #461 on: 19/12/2011 03:09:00 »
Mass is particles, particles has a density. The density is defined through their size relative what invariant mass we find them to have, you can also translate it into 'energy'.

Two scenarios.

Assume a particle accelerator 'A', accelerating particle x to 99% of lights speed in a vaccum. This accelerator is placed on Earth 'A'. And relative the CBR (Cosmic Background radiation) moving at 0.5 the speed of light. The accelerator is linear, constructed  to point in the line of Earths motion, relative the CBR.

Then build an exact same linear accelerator on planet 'B', being a exact copy of Earth, but 'at rest' with the CBR. No apparent motion at all relative it. And assume everything from location to 'gravity' to be the exact same as with 'A'.

What energy do you expect to be expended to get particle 'x' to reach 99% of lights speed in a vacuum?

For 'A'
For 'B'

Relative what?


What will you see when accelerating 97% of lights speed in a vacuum? The Lorentz contraction will redefine the SpaceTime you see, it will be contracted in the direction of motion.

Assume a 'SpaceTime' of ten objects of varying mass, 'Gravity' will then be coupled to those objects defining it. From Earth you now define the distances locally, as well as the 'gravity' you expect. When you are at 99% of lights speed in a vacuum that distance must contract. Now define the 'gravity' there is in that SpaceTime, relative the ten objects.

Will the ten objects invariant mass change with your 'relative velocity'?

What will happen to those objects lined up in front of you as you close in to lights speed in a vacuum?
As they get closer to each other, according to your frame of reference, will they have a stronger attraction towards each other?

Why not?
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #462 on: 19/12/2011 03:19:19 »
You could, as a very outlandish notion, assume that as you come for ever closer to 'c', relative whatever you define that apparent 'velocity' from, also assume that as 'time speeds up' relative your local clock for all 'frames of reference' not at rest with you. Then the universe must contract at some 'future time'
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #463 on: 19/12/2011 03:39:27 »
Why it would have to contract has to do with how we define 'events'. They must fit for all observers, even though we might disagree on time and position. But as I now use the 'speeding' frame of reference you can argue that in the former 'still frame' that Earth represented it won't be true.  But events must fit if you want us to have the same universe, So either is a Lorentz contraction a illusion, or the 'speeding frame' should be a true representation of a common 'future'.

And then we have 'light' itself, always at 'c'. The constant we call, a 'speed'?
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #464 on: 19/12/2011 04:56:02 »
There is one more. The arrow of time. Time symmetry is a very weird definition, and very theoretical in that no one ever has been able to travel 'backwards' in our 'arrow of time'. But the symmetry is there and able to be utilized as Feynman did in his Feynman diagrams.

"“There are many theoretical physicists who think the flow of time is an illusion,” he says. “And I think that’s a great mistake…according to quantum physics you don’t know the outcome of events until they happen. We know what happened in the past, there’s a time called the present when things are happening, and there’s a time in the future which is not yet determined. That’s my view on it, which is not a very widely supported one.”" Said by George Ellis, professor emeritus of applied mathematics at the University of Capetown.

I agree.

"Ellis adds that Einstein also hated the idea of a beginning of time. It does seem rather odd that something with a very distinct beginning would simply have no end, or to think that even 14 billion years after the big bang (if the universe is infinite) we are still infinitesimally close to the beginning.

It seems the discussion of time swings quickly between the largest scale and the smallest scale. Discussion of the ultimate length of time begs the question, is time quantized? Can we break it up into packets like photons and quarks?

Markopoulou-Kalamara says it depends on your notion of time. In terms of the geometric notion of time, as in the time dimension of a space-time, she says yes; she believes it has to break down. But if you’re referring to time as change, something that has happened, “I doubt it,” she says. Ellis adds that quantization of time may have to confront something like Zeno’s paradox of infinite halves:"

'c' as a 'clock beat' does it. And defines 'frames of references' relative local clocks, as ideally Plank sized. But it does not answer 'what' time is, it only tells you how our universe 'count its beats'.

But maybe that is the arrow. The 'inflation' and subsequent 'expansion' becoming the reason for creating those 'distances' we define. Those 'distances' that won't 'fit' conceptually, until Lorentz transformed. The arrow becoming a geometric expression of SpaceTime, relative 'c'. But if you then assume that with a expanding SpaceTime must come a 'slowing' of time, you're stuck in the old ways looking at invariant distances.

It's not a 'speed', it's a constant. And a 'distance' will always be real to you, but only from a local definition relative your own 'local' clock.

The universe has one, always strictly local, ground beat. That ground beat also becomes the 'curtain of light' that connects my locality and definitions of 'reality', to your definitions of the same. Created through 'locality', as interpreted through 'c', relative 'distance' as measured by your local clock.

The expansion needs a arrow, just as the arrow always need a distance to create itself.
Because that is how we define it.

Time Since Einstein.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #465 on: 19/12/2011 05:59:45 »
This one is interesting to me, and maybe to you?

Internal Space-time Symmetries according to Einstein, Wigner, Dirac, and Feynman  By Y. S. Kim, Marilyn E. Noz.

"When Einstein formulated his special relativity in 1905, he established the law of Lorentz transformations for point particles. It is now known that particles have internal space-time structures. Particles, such as photons and electrons, have spin variables. Protons and other hadrons are regarded as bound states of more fundamental particles called quarks which have their internal variables. It is still one of the most outstanding problems whether these internal space-time variables are transformed according to Einstein's law of Lorentz transformations. It is noted that Wigner, Dirac, and Feynman made important contributions to this problem. By integrating their efforts, it is then shown possible to construct a picture of the internal space-time symmetry consistent with Einstein's Lorentz covariance. "
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #466 on: 19/12/2011 13:25:12 »
Better point out that I don't expect it to be true that a relativistic speed describe the SpaceTime you 'must meet in a future', staying at home. If it was it would be enough with one relativistic rocket for the whole of SpaceTime to 'contract', and that one seems quite improbable. But it has to do with 'events' and gravity. And that's one of my newest questions.

If a distance contract, what happens with the SpaceTime geometry? What happens with 'gravity'? And getting close to 'c' those objects should, according to you 'speeding away' be closer together. That must mean that they also will 'attract' each other, if a Lorentz contraction is as real a effect as what you define SpaceTime to be before taking of, being at rest at Earth.

Don't you agree?

Or can you keep the cookie, and eat it too?

:)
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #467 on: 19/12/2011 13:29:29 »
And it also has to do with how you define a SpaceTime. As a 'common, whole' SpaceTime, defined through Lorentz transformations. Or as a SpaceTime defined through 'locality' relative the local constant 'c'?
=

'c' will give you Lorentz transformations any which way as I think of it. So I don't think you can use that as the final argument for any of the suggestions above?
« Last Edit: 19/12/2011 13:31:54 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #468 on: 19/12/2011 13:50:25 »
What I'm aiming at is the later approach. The one where we go out from 'locality' and define our 'common SpaceTime' as a effect of that local constant. It seems to me as the most realistic approach for now, where what you observe relative those objects Lorentz contracted is real. For you it will be, but for me, still being at home it will not be so in some 'future'.

But if I define it that way, what happens with the idea of 'events'?
Well, what happens with 'events' if I don't define it as that?
=

There might be some effect that I'm missing though, explaining why 'gravity' won't attract more, the more contracted you observe SpaceTime to become. And there is always the possibility of it being a 'illusion', although I don't expect that to be true myself.

There are some things here that I still has to come to grip with. One is my inability to see what a speed 'really', and I mean, really means? :) Another is uniform motion relative accelerations. The definitions I use rests on that all uniform motions becomes the same inside a 'black box scenario'. That means that no matter your speed, relativistic or not, you still can be defined as being 'at rest' in a uniform motion. But it also differs between different uniform motions, as being fast, faster, fastest. So as defined relative some common origin, or just by common agreement, we can define different 'speeds', which then can become 'relativistic'.

Because you can be Lorentz contracted and 'at rest'.

« Last Edit: 19/12/2011 14:22:48 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #469 on: 20/12/2011 11:36:06 »
You can turn the reasoning around of course. Pointing out that those ten objects in that SpaceTime, all in a uniform motion, won't find their 'space' to contract at all just because I speed up, which is true. So from their 'frame of reference' gravity won't change. But how does it fit? If I move uniformly very fast, at 99% of lights speed in a vacuum, being 'at rest'. Won't I still observe a Lorentz contracted SpaceTime before me? And now I'm actually 'at rest' too, definable as being the exact same in a black box scenario as all other 'speeds/velocities', indistinguishable from not moving at all inside that black room.

So 'locally' I'm at rest, but 'globally', as relative the SpaceTime outside that room I am 'moving'.

So, is there a Lorentz contraction uniformly moving? Well yes, there should be. Then I 'shrunk SpaceTime' right :) But that same SpaceTime will have their own definitions of the 'shrinking' I observe as my reality. and each one of those 'objects' most probably experiencing one unique SpaceTime per 'observer' on them.

So, does this make sense from a 'globally same' SpaceTime?
I don't know, but I like 'locality' better myself,
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #470 on: 20/12/2011 11:55:44 »
Let us put it like this.

You have three platforms in space, all three uniformly moving.
Each platform are measuring the other platforms uniform 'speed/motion'.

All three use Earth as a definition of a null speed, being 'still'.
Each one has a different uniform motion relative each other, as defined relative earth.

Each one send out an rocket, built to the same exact specifications, using the same acceleration as well as the 'same time' measured from each rockets own local clock.

Will it matter what speed they have relative Earth, or relative the platforms, for defining in local time when reaching 99% of lights speed in a vacuum? As their platforms uniformly moving 'fast, faster, fastest' relative each other.

All platforms uniformly moving, but when comparing their uniform motions finding speed differences. If you think it will matter, then you also should expect there to be a objective, 'globally' correct, way to define a 'speed' in SpaceTime, as a guess? And then, you and me both, look at 'c' as a 'proof' of a 'speed limit' :)

But..

=

Yes, they all accelerate in the direction of the platforms motion.
« Last Edit: 20/12/2011 12:00:13 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #471 on: 20/12/2011 12:05:57 »
You can't use the argument that with different speeds becomes different 'arrows of time'. That one will always need a different frame of reference. To do so we would have to imagine a observer on our, arbitrarily defined, 'still' Earth. If measured inside that black box all three platforms are 'still', no matter if they are moving relative earth. And using my definition of 'ideal clocks' all platforms will find their local time to be unchanged by their 'relative motion'.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #472 on: 21/12/2011 10:35:41 »
So I started to wonder about potential energy and gravity again. In mathematics you can say that it has a value depending on where you measure it relative the 'gravitational field'. And you measuring infinitely far away, the way it is set up mathematically, will give you a negative value for potential gravity, and so also for the potential energy.

"For the conservation of energy to work, the sum of the Kinetic energy "T" of a body pulled by gravity, and it's gravitational potential energy "U", must be a constant.

T+U=C

Kinetic energy is always positive, and will increase as the body falls faster and faster towards your source of gravity. To compensate, U is going to have to be zero. If it was positive, the total energy C would not be constant. Sort of a fudge, but necessary if you want the conservation of energy to work. You get around it by making the gravitational force equal to minus the gradient of the potential energy. F=-\nabla U.

A negative U makes sense in some way, because your gravitational energy, though always negative, increases as you move away from the body, i.e. upwards. You expect gravitational potential to do this, increase, as you move up, so that you'll gain energy as you fall. If U was always positive, but decreasing, it would mean that potential energy would decrease as you moved away from the body. Also, if you tried to make it always positive but increasing, though the potential energy would approach a maximium, your effort would be confounded as you moved close to the body, i.e. as x->0.

The choice of negative potential energy is really the best of a bad bunch. Try graphing the equation, then graphing it's negative. Move both graphs up and down by constants to get a feel for why the canonical option really is the lesser of many evils." By ObsessiveMathsFreak.

So, what is gravity then?

Maybe a better question would be. What is SpaceTime? Because that's the real question. In Einsteins relativistic universe you have four acknowledged dimensions. three that I sum up as creating 'distances' in a three dimensional space and.. This is where so many miss the importance, exactly because the way it is presented.. Time, or its arrow.

It's not correct to write it like this. SpaceTime is one thing physically and mathematically as I understands it. Represented by four dimensions together. You can lift them out and 'isolate them' in mathematics, but not in reality. Too many seems to think that because I can turn something around then that must represent a true solution too. Mathematically it might, but you need some sense of proportions to see if it is consistent with the world you live in.

So, potential energy, and Gravity, outside the text book does not 'cling off' into negative expressions as far as I understand. If they did we would have anti gravity :) and ?? anti potential energy flowing all around us, whatever that would be? And disregarding fantasies, there are no such things observed in this universe, and no experiments validating it that I know of.

Potential energy is a relation, not something 'touch able'. Gravity is a relation too, expressed through accelerations (constant or variable 'inertia') invariant mass, also able to be converted into the notion we have of 'energy', that then might represents some ultimate quantity, or better seen, as transforming 'usable work -> into -> Work done. To imagine what 'energy' might be we either has to use a wave or a 'photon'. That's the cleanest expressions I know, allowing us to measure.

The SpaceTime we see is expanding. Using mathematical concepts, as differing from reality, of positive versus negative energy we then need a explanation to from where that 'expansion energy' comes from. In a closed universe you will expect a balance, we use the conservation laws to express that. So if the room expands the 'energy' for that has to come from somewhere. But it might be wrong. Maybe the room expanding has nothing to do with our notions of 'energy'. We might overreach in defining negative concepts that bears no mathematical resemblance to reality, not fitting what we see as we measure and experiment. Use my 'curtain of light' and imagine it to be a 'game' for a second. Then the 'discrepancies' we see in QM as related to SpaceTime becomes where the logic of the game points to something else.

People tend to believe in choices, QM is the 'truth', as it's describing the smallest constituents of our universe, and Relativity will need to adapt. Or Relativity is true, and it is QM that needs to adapt. QM does away with the notion of classical causality chains, or, QM is not describing it all (hidden parameters). How about a third one, neither QM nor Einstens relativity catches 'it all', but they both describe, the same universe? That' seems better to me. Both describe reality, from two perspectives, physics using 'scales' to find the differences. Both has a beautiful logic to them, although neither of them is what we see in our daily life. There we have a third description that works just fine, Newtonian mechanics.

But relativity does not state that conservation laws must hold. In fact it seems to depend on what you believe, not on Einsteins equations per se. You are the one bending them to your needs. I find conservation laws to make a enormous lot of sense myself, as describing interactions of various kinds. But I'm not sure if the universe is 'closed', and neither should you be. If it's not then Noether's theorem shouldn't be relevant for a SpaceTime geometry. That means that we don't have to look at 'energies' being shuffled around inside a closed 'box' as the geometry might have another definition. Space isn't there classically, and that one we can prove with any vacuum. So to expect nothing to grow into more 'nothing'? Becomes somewhat of a oxymoron looked at that way.

You only need to consider what different observers will define as being the 'energy' observed, to see that it is observer dependent. And that one is just like 'time' and 'distances'. Relativistically described your universe 'shrinks' with your relative motion, and mass. Your positional definition change both in time and in distance. And as you can measure it to be true for you, the question becomes what a measurement really should mean. There I prefer to define it from 'locality' instead from 'Lorentz transformations'. That actually makes me more in tune with what we deem a repeatable experiment, than placing myself and my definitions in a abstract 'mindspace' where nothing is 'true', before you made the necessary transformations. And as I see it it's not only relativistically time dilations and their complementary Lorentz transformations exist. They exist, as I expect, here and now. I don't need a relativistic 'speed' for it, although we may have trouble measuring it.

And yes, it can all be expressed in 'energy'. But what the he* does that mean? That we are 'energy'? Nope, we're 'matter'. Are we then, 'waves'? Nope, we're still 'matter'. 'Photons' then, we are the 'Photons', right? Nope, matter..

Matter is one thing, photons another, gluon s a third, Higgs bosons a fourth, etc etc, add infinitum. They are not the 'exact same'. If they were, we wouldn't be here arguing, well if you're not going to get mystical on me, telling me that we are the consciousness creating the 'world'? To say that we can follow a logic from 'matter' to 'energy' is not the same as stating them to be the exact same.  And neither does it demand that all 'bosons' must be 'waves', or for that sake 'photons'. The wave particle duality still exist, and is not solved into being one or the other. And if you to that add all other presumed bosons existing, and why not add 'thoughts' to the mix? After all, without those we wouldn't even care.

Are thoughts 'bosons' :)
« Last Edit: 21/12/2011 10:45:46 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #473 on: 21/12/2011 11:38:12 »
Luboš Motl might be seen as slightly confrontational at times :) But he has a clear mind when it comes to physics, and I enjoy reading him. He has this to say about  Why and how energy is not conserved in cosmology  and Michael Weiss and John Baez says this about Is Energy Conserved in General Relativity? I'm not sure any of them would agree with me in considering a vacuum to be a geometry, and at times I'm not sure if I agree with myself on it either. But, as someone once said "So I disagree with myself, Bah, so what? I contain multitudes."

And if that doesn't satisfy, here you have a third point of view. Square Root Of The Universe.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 12001
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Re: An essay in futility, too long to read :)
« Reply #474 on: 28/12/2011 14:16:42 »
Gravitational field, what is it?
And uniform motion, what does it have to do with geodesics?

Our three platforms above, they are in a uniform motion, but are they in a geodesic? Yep, as far as I define it they must be in a geodesic. If they weren't then they would be 'accelerating' in some manner. If they 'accelerate' the motion they describe will not be uniform.

You can move your arm uniformly, is that arm then in a geodesic as you move it? Is that a motion uniform, or is it a accelerating motion? As soon as you are in a gravitational field you will 'fight gravity', no matter what kind of motion you define that 'fight' to have. Accelerating or 'uniform'. Can you see what I mean?

The only time you will be close to a geodesic is when 'free falling' on Earth. So a geodesic must by definition become when you do not 'fight' gravity. What does that tell you about 'space'? What is needed for a geodesic to exist?

Gravity.

You need gravity as the definition from where you/it stops 'fighting' it.

Tell me again about those remarkable 'patches' of zero gravity in space? Where gravity doesn't 'exist', unmeasurable? How can I fit a geodesic to such a place? Gravity defines 'space' to me, so having no gravity, I would say you've run out of 'space' too. And so to me becoming similar to our ideas of singularities. Those weird 'places' in where we can't 'see in'. IN SR you use the concept, in GR, and reality, you can't, not as I see it at least. And that's also Einsteins genius. To build it from a concept which is purely theoretical and mathematical into something that fits the reality we see as a glove fits my hand.

Transformations then, and mathematical rotations. Are they magic? Nope, they are standard mathematic tools used to rotate and 'move' thingies, like vectors defining a direction as well as magnitude, to some other 'place' to then compare them, also allowing us to define how they differ in/with time.

Think of a circle, assume yourself rotating inside its center, you holding a rope stringed to a ball,the whole contraption tensed outwards at a straight tangent by your rotation. Any time you let that ball go it will do so at a straight tangent to your rotation. Let those tangents become lines pointing outward in your imagination. Let each one represent a vector, meaning that your line (vector) has a direction (and a defined 'time slot') as well as a magnitude (a 'force' of sorts). release the ball, let some time pass, release the ball again.
(Yep, a magic ball, always leaving:)

Now you got two lines pointing out at a straight angle from your circle, differently placed in time on it, representing two vectors. The trick with a vector is that you can 'lift a line up' to then move it, as long as you do so keeping its original magnitude and direction. When you do so you ignore the 'time' differing them, but it helps getting an idea.

Now, if you let those two lines (vectors) originate from a same 'point' on your circles circumference, you can easily measure how their directions differ. That new line you will find, measuring the two lines difference will invariantly point in, towards your circle's center. To prove it you just need to move that new line you got to touch the circumference of the circle. So the centrifugal force you felt can now be defined as to point inwards to that center. Can you see what I mean? Now becoming a centripetal force instead.

The acceleration that's hidden in this example is not the speed, as we will assume that to be uniform all the time you spun around. Instead you find it in the 'force' it took you to break the SpaceTime natural geodesics, loosely represented by the balls leaving you. And that's also what we measured rotating, or moving, those two vectors together, then measuring the angle between them, getting that new 'line'.

And that's also the difference between a speed and a 'velocity'. That ball you spun around with had a speed, but it didn't have a velocity. But as soon as you let it go, it begot a velocity, now having both a direction and a magnitude in SpaceTime. So when we speak of light having a speed instead of a velocity we give light a constant magnitude, but we say nothing about a direction. And that is perfectly correct, light only exist in its annihilation, and possibly also as defined by the recoil we observe its 'source' to have. But that last description is not a 'photon' strictly defined, that's just the effect of a 'change', as expected of the conservation laws.

So we can define a source and a sink to a photon. and we get an explanation of the recoil in the conservation laws. Doesn't that mean that we also can define it a 'path'? Weak measurements thinks it does, I don't.

All mathematics use coordinate systems, you do it too. Every time you want to meet someone you use a coordinate system to define it from. "We'll meet where Anna spilled the juice all over her" is defining a coordinate system, in space and time, using a common reference frame known to both of you. Or you could have used the name and number of the street where it happened. It all boils down to one thing, coordinate systems is a construct, humanly made. We use 'time' and some common references to define them from, as miles, km, feet, altitude, meridians, etc etc. All of them conceptual.

You can rotate and move coordinate systems, or, as they all are used to define locations of objects, instead rotate and transform the objects locations in some conceptually made coordinate system. Draw two lines y| _ x That's a coordinate system too. |_  it's now a 'frame' of a sorts, in where you can depict something, moving or not, also giving your 'x' and 'y' axis some values to measure that object from/in.

What defines a coordinate system in SpaceTime is 'time' and 'distance' relative some defined 'anchor points' like Earth for example. Distance being the 3D representation of a 'space', measured by your ruler relative your clock, as your wrist watch. This definition is the only one that will be comparatively true for you, measuring in Relativity. Using someones else's clock you will get the wrong measurements, same as if you used someone else's ruler. And that sounds weird but it all boils down to one thing.

Lights unvarying speed in a vacuum.

'c'

Nowadays a lot of the guys knowing math seem to have lost sight of that. The problem being that that the more advanced those mathematical concepts become, the less anchored they become in what we percieve directly. Axioms building on Axioms building on Axioms. Mathematics is not the truth. What you live and observe is the truth, all mathematics we have growing from such observations.

All our original axioms comes from direct observations of the world. Building and assuming from the original definitions we can get new axioms not directly observed, although logically inferred from the original axioms. The problem with all those kind of definitions that they in the end builds on so many assumptions, and sometimes presumptions, that they becomes almost impossible to untangle back to the original axioms they started from. And that's quite dangerous because what it ends with are like people only referring to the concept of simultaneity, somehow ignoring where we got Relativity from, 'c'. Use 'c', and you can reinvent Relativity. Don't need no simultaneity to do that, even though the concept follows naturally.

Like the Higgs. Assume that we do find a 'boson', is that then what we think it is? We did find a 'boson', but how can we prove that it is what creates 'gravity'? It will be a very theoretical 'fact', and as soon as someone comes up with another theoretical definition of what that Boson possibly does, a Higgs becoming questionable, leaving you to decide it from beliefs instead of 'science'. And that's not acceptable to me. But that's the problem today, too much 'esoteric' math combined with too few direct observations as we penetrate the quantum realm. Math is a very fine thing, and lots of its implications are of enormous value, even though difficult to prove. Symmetries for example, conservation laws, Noethers theorem, all extremely important to me for describing SpaceTime. And never forget, 'black box scenarios' for testing your logic. But using what we infer, expecting that to be the same as something directly observable, is to me like standing on a morass inviting your peers to admire your newly built motorway, "Yep, and it goes all the way, to the stars"


Don't think so.

« Last Edit: 28/12/2011 14:28:41 by yor_on »
 

The Naked Scientists Forum

Re: An essay in futility, too long to read :)
« Reply #474 on: 28/12/2011 14:16:42 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums