Aethelwulf

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Posts posted by Aethelwulf


I'm sorry, I've never heard of it.
Since you will be better read than me on the subject, can you tell me how [math]\tau[/math],this evolution parameter defines time? How is it applied to the universe as a ''whole''?
I'm reading this right now to get some idea on it http://www.platonia.com/complex_numbers.pdf
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Right, so I said I would try and explain what a rank 2 tensor is. It's difficult trying to explain this stuff to anyone  even when you are trying to teach something to someone in a very short post  but I think I have a way that can help you understand it.
Some simple equations to consider might be
[math]A_{(y)}^{m} = \frac{\partial y^m}{\partial x^y} A_{(x)}^{r}[/math]
The upper and lower indices here [math]A_{(x)}^{r}[/math] are called the ''components of the vector.'' Consider a second one as well
[math]B_{(y)}^{n} = \frac{\partial y^n}{\partial x^s} B_{(x)}^{s}[/math]
How would we write our first tensor mixed in with our second tensor? You would have to mix them in an appropriate way:
[math]A_{(y)}^{m}B_{(y)}^{n} = \frac{\partial y^m}{\partial x^y}\frac{\partial y^n}{\partial x^s}A_{(x)}^{r} B_{(x)}^{s}[/math]
And that is us, wasn't too hard eh? This is what you call a mixed tensor of ''second rank''. We can identify it by changing it slightly
[math]T_{(y)}^{mn} = \frac{\partial y^m}{\partial x^y}\frac{\partial y^n}{\partial x^s} T_{(x)}^{rs}[/math]
Think of these upper indices as counting the rank of your tensor, so the upper indices [math]T_{(y)}^{mn}[/math] would count as a second rank tensor. The tensor above is in fact a contravariant tensor because the important indices just spoke about are on the uppercase. If they are lowercase, they are covariant tensors:
[math]T^{(y)}_{mn} = \frac{\partial y^r}{\partial x^m}\frac{\partial y^s}{\partial x^n} T^{(x)}_{rs}[/math]
And viola! That's you done.
If you need to know anything else, I will be happy to try and help.
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Since the gravitational charge is the mass which can change due to velocity, I feel the need to quote Taylor and Wheeler here:
''The concept of 'relativistic mass' is subject to misunderstanding. That's why we don't use it. First, it applies the name mass  belonging to the magnitude of a 4vector  to a very different concept, the time component of a 4vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself.''
If they are correct, then the gravitational charge cannot change due to velocity because the gravitational charge is treated in this work as an intrinsic internal property. Instead, the gravitational charge only appears to change because of a change in energy which is resultant from the spacetime geometry. Which is a fascinating thought.
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It's your conjecture, but if I have 1 GeV photon, I can think of particles that have less energy. The description of a photon as the "smallest amount of energy" is nonsensical, especially if you then take the position that you aren't going to quantify it.
I think it's splitting hairs somewhat  the photon is the smallest unit (piece) of energy known. You can't get smaller than a photon. This is well known in physics  known among many scientists.
A photons size would vary according to the frequency. The lower the frequency, the smaller the size.
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Dawkins is actually who I was referring to. He is a materialist, (Biologist) and Hawkins, he's the real McCoy, a (Physisist). I guess it's only a matter of what someone wants to believe, especially if they are already leaning in that direction. Having read some of Darwins stuff, research; I can see where Dawkins justifies his basis for a constantly evolving system. Everything from a single cell to a blue whale. These are physical things we can touch and see and in many cases able to control and alter ourselves. When science say they can boost corn growh and yeild through genetic engineering and you see the results in just a few short years, i doesn't take much to convince you that the process works. A more plump and juicy turkey for Thanksgiving, no problem. A bit of genetic tinkering and we can grow 25 & 30# ers.
Hawkins and physics are to me a whole different ball game. And yes, it's because I understand very little of physics other than basic principals and even then I'm not always sure of the facts. So, when physicists predict the absolutely unpredictable and draw it up like a scrabble sheet, it's troublesome to many of us. And for gods sake, unless you are one of the fellows; never ask a question that you didn't answer with your own question. If it requires more than a wink and a nod. Brrrrr! Well, maybe this whole thing may freeze over in a billion years or so. But to whom are you going to complain if things work out differently?
Hawkins?
You do of course mean...Steven Hawking. Has a ''g'' and there is no ''s''.
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How do you work out the spacetime curvature according to general relativity? Iv seen the special relativity equations, but never the general
You work out the spacetime curvature using what is called the Curvature Tensor. I will write a bit up later on it to help explain it to you.
I will write something up in about half an hour, I am just getting something to eat first.
I have going to have to explain this as quick as I can because my life just got very busy lol
You're gonna have to know some math to completely understand this, even some knowledge on tensors. I can't explain everything today. The thing which calculates curvature in General Relativity is the Riemann Tensor and its given as
[math]R^{\rho}_{\sigma \mu \nu} = \partial_{\mu} \Gamma^{\rho}_{\mu \sigma}  \partial^{\rho}_{\nu \sigma} + \Gamma^{\rho}_{\mu \lambda} \Gamma^{\lambda}_{\nu \sigma}  \Gamma^{\rho}_{\nu \lambda} \Gamma^{\lambda}_{\mu \sigma}[/math]
The part [math]\Gamma_{\mu}\Gamma_{\nu}[/math] is what you call the commutator of two matrices.
You can rewrite it more compactly when you bracket expressions and realize that these are the derivatives of the connection ''Gamma''
[math]\frac{\partial \Gamma_{\mu}}{\partial x^{\nu}}  \frac{\partial \Gamma_{\nu}}{\partial x^{\mu}} + \Gamma_{\nu}\Gamma_{\mu}  \Gamma_{\mu}\Gamma_{\nu}[/math]
You can only get the Riemann tensor by contracting the ''Ricci Tensor''. Notice that one alpha is on the upper indices and one is on the lower indices:
[math]R_{\mu \nu} = R^{\alpha}_{\mu \alpha \nu}[/math]
Repeated indices means you automatically sum over these indices. The lowercase [math]\mu \alpha[/math] actually describe some rotation plain for a very small area displacement [math](dx^{\nu}, dx^{\mu})[/math]
You can also contract using the metric, for instance
[math]R_{\lambda \sigma \mu \nu} = g_{\lambda \rho} R^{\rho}_{\sigma \mu \nu}[/math]
Can you guess which one is contracted? If you said [math]\rho[/math], you'd be right. What is [math]g_{\mu \nu}[/math] contracted with [math]R^{\mu \nu}[/math]? It's just [math]R[/math] is the answer. You would get the curvature scalar by contracted the Ricci Tensor [math]R^{\mu \nu}[/math] and has this following form
[math]\nabla_{\mu} R^{\mu \nu} = \frac{1}{2} g^{\mu \nu} \partial_{\mu} R[/math]
where we call [math]\nabla_{\mu}[/math] the covariant derivative. I think the covariant derivative originally came from work on fibre bundles. The property of a covariant derivative just has this form:
[math]\nabla_{\mu}AB = A\nabla B + (\nabla A) B[/math]
The covariant derivative of [math]g_{\mu \nu}[/math] is actually zero.
[math]\nabla_{\mu} R^{\mu \nu} = \frac{1}{2} \nabla_{\mu}g^{\mu \nu} R[/math]
[math]\nabla [R^{\mu \nu}  \frac{1}{2}g^{\mu \nu} R ]= 0[/math]
This can be rewritten as a shorthand
[math]R^{\mu \nu}  \frac{1}{2}g^{\mu \nu} R = G^{\mu \nu}[/math]
so
[math]\nabla_{\mu}G^{\mu \nu} = 0[/math]
This is the local continuity equation for gravitational energy. As I said before, [math]g^{\mu \nu}[/math] derivative is zero, so what we have is
[math]R  2R = 0[/math]
and [math]R=0[/math] when there is no energymomentum present.
So we learned the ''Einstein Tensor'' [math]\nabla_{\mu} G^{\mu \nu}=0[/math]
The right hand side of [math]\nabla_{\mu} R^{\mu \nu} = \frac{1}{2} \nabla_{\mu}g^{\mu \nu} R[/math] describes the matter in a universe. Even when matter is zero, it does not mean that curvature has to be zero. Gravitational waves for instance and other forms of energy can cause curvature in a vacuum which is an interesting facet of the theory to keep in mind. Now all this stuff is related to Einsteins equations because they can either derive the equations or be derived from his field equations. They are what you call a rank 2 tensor, and If I have time later, I will come back and explain in some detail what a rank 2 tensor is by introducing a new thing for you to try and understand, called contravariant and covariant tensors.
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Then you misunderstand what I am disagreeing with. I perhaps should have been clearer. I agree that there is such a thing as a ''unit of measure'' for a joule and even descriptions of other measures as well. What I was strongly disagreeing with was this description in my context of things  why do you think I started pulling out definitions and describing it as an elementary structure?
As for having an energy smaller than a photon, do you of an example?
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If you read my message you would notice at least two things: (i) I wrote about the generator K (K is not H) and (ii) I differentiated evolution time (sometimes denoted by [math]\tau[/math]) from x^{0}.
Note: The notation is standard and can be found in papers and books, but before someone adds some new misunderstanding... let me add that [math]\tau[/math] is not proper time.
I don't know what you are arguing. You explicitely said that time is the evolution of the universe  this is wrong. When you quantize the EFE's, you get the WDWequation
[math]H\psi> = 0[/math]
Does not allow a global time translation of the universe.
If you read my message you would notice at least three things: (i) Nowhere in my message I mentioned General Relativity, because the general relativistic concept of time is very far from being fundamental;
You've edited a part of thus:
If you are now talking about ''fundamental things''it would best not to talk about ''the universe as a whole''. Global concepts are less fundamental than the Local concepts. Time is local strictly. You can't talk about ''time for the universe as the whole'' as you put it and I strongly stated why.
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How many photons in a Joule?
Not what I was talking about. ''Unit''  an elementary fragment, a ''unit of energy'' as in a single particle of energy.
Your definition or use of the phrase was different to mine. I tried to explain this above.
Even an ''elementary unit'' as meaning an ''elementary particle''.
I don't have time either for quibbles on terminology differences of ''mass vs matter.'' I may from timetotime freely exchange them. They are quibbles to an untrained eye and just a nuisance to talk about otherwise.
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Electromagnetic Biofields exists... but I doubt this is what you had in mind.
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This is a difficult question. Time is, in essence, the evolution parameter of Universe as a whole.
Magueijo's ideas are incorrect and outdated. As many others, he is not aware of the difference between the time associated to the generator of time translations K and the x^0 in 4Dspacetime.
Never mind Maguejo, I'd be concerned with your answer.
Time is local  there is no global time in General Relativity. So it cannot be an ''evolution parameter of the universe as a whole''. Time vanishes in GR because world lines are static and diffeomorphism invariance is not even a true time evolution, motion arises as a symmetry of the theory.
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Writing the above in a simpler form,
[math]GM^2 = \hbar( \frac{E}{mm_0})[/math]
The extra energy of any moving particle is directly related to an increase of the energy of a system  Indeed, this is what led Einstein to the idea that perhaps all inertia is is the energy of some system. I believe this is true as well.
I defined it as a special type of energy, the gravitational energy of the system [math]E_g[/math], to differentiate from nonrest energies. This must mean that the gravitational charge must vary as well proportionally to moving particles.
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No, it isn't. A photon has energy. It is not a unit of energy.
Energy and mass are equivalent. But mass is not the same as matter. Mass, too, is a property. Is there such a thing as pure mass?
A photon is the smallest amount of energy we know of...what better unit to measure energy by? If you know of a smaller energy I stand corrected.
A pure mass would be? What is a pure energy? Energy is energy, mass is mass. The purity of the two do not variate between particles.
I think I should make it clear, that Swansont's objection to ''a unit of energy'' may be related to the idea that a photon is not a unit of measure.
I disagree entirely.
Let us look at the definition of a ''unit''  a terminology for a photon which is used much;
'' 1.
An individual, group, structure, or other entity regarded as an elementary structural or functional constituent of a whole.''
Notice, it is a structure or elementary functional constituent of a whole. By unit, I mean such this. what Swansont means, he needs to learn to explain himself. For... you cannot get much more elementary than energy itself.
Even our most recent poster has noted that energy comes as corpuscular packs. The word ''packs'' here can be exchanged for ''units'' as they pretty much mean the same thing.
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you're welcome.
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If the universe was infinte,and without boundaries would it be logical to conclude it would be infinite in time also?
Yes, it can be contending to think that it is infintely expanding, meaning that there is an infinite amount of space (including time) abound. Infinity just means ''one more than now''.
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This also goes along with my simple concept of time.
Now back to energy and its essence. One of my main points was that energy, like time, I think is also a manmade concept which also comes in very handy to explain observed reality. It has physical characteristics like photons, and maybe physical waves in the form of a particulate background field waves. De Broglie, who discovered matter waves, believed in their having a physical existence. In the same way EM radiation was once proposed to have a carrier particle forming waves and having energy of motion like the old aether models  or particulates like dark matter or some other modern proposed background field particulate(s) model, mostly nonmainstream.
//
Well... it's harder to say energy is a man made concept, because it is out ''there''. We can measure the spin of a photon for instance, which is generally considered one of the most basic units of ''energy.''
What might be invented is it's interpretation... energy itself however has been measured  the difference with time is that it truly hasn't outside of our subjective experience of it. This is why time is not truly an observable. It's not really something with anything ''physical with can be measured'' about it.
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As far as we know, i.e. to the extent it has been tested, it does not have antigravity. There are people trapping antihydrogen who are aiming to improve testing of this.
We haven't actually tested it enough to be certain. From the last records I read... The amount we have made is miniscule.
Do you have a link where I could stay up to date with there research
The page I read this from was a NASA page, if my memory serves (which it usually does).
Trust me, we have not created enough of the stuff to see noticable gravitational effects.
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I will reply with the statements at least you may think there is some objection to:
''In this way I think the meaning of "the flow of time" refers to the unimpeded singular direction of time  that time cannot go backwards. This is where there can be disagreement in the theory of time. My view is that time is a very simple manmade concept which can be solely defined as: "an interval of change" and nothing more. But there are many others in quantum physics that would make the definition of time much more complicated. Bottom line is that there are different hypothesis both mainstream and otherwise, as to the essence of time. ''
This is right, the first part. (not that the rest must be wrong to mention)  that the flow of time means a certain directionality to time. To be honest, timereversal is a much abused concept in physics  we have no evidence for it. The days when physicists argued whether there was an arrow in time (an omega point) is what brought about the idea that maybe when the universe gravitationallycollapses is what would induce a time symmetry when objects would ascend from the ground and reassemble on the table, like the cup you dropped but broke on the hard floor due to the gravitational force... (just read Hawking's a brief history of time for this example).
What is mainstream however is the view I have taken: The idea is that there is no flow, that is it rather a succession of beginnings and ends.
I don't even think you had a major disagreement with this, but was worth mentioning. The rest you seemed to agree on, which is good in my eyes
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[math]\frac{GM^2}{\hbar} = (\omega \times r_s)[/math]
Since [math]\omega[/math] will lye along the axis of rotation, and if [math]r_s[/math] defines the radius of our system which could or may not be set equal to the Compton Wavelength, and if this is related to the quantized condition
[math]\hbar = \frac{GM^2}{c}[/math]
Then I ask, is there some kind of spin relationship between the square of the gravitational charge of a system (perhaps along the same lines as a Gravielectromagnetic force) with the angular spin of a particle?
We'd have to start thinking about inertia as well, even in a classical sense. One derivation I came to followed the lines:
[math]M=\frac{r^3}{2Gt^2}[/math]
multiply M on both sides and then rearrange
[math]2t GM^2 =Mr^3[/math]
What we established from my derivation in the OP was
[math]GM^2 = E_gr_s[/math]
Set [math]r=r_s[/math] again, and substitute meanings and then divide by radius we get
[math]2Et^2 = Mr^2[/math]
It turns out after a little investigation that [math]Et^2[/math] is defined as an inertia of bodies from two separate sources:
http://books.google....squared&f=false
http://www.worldscin...5902000638.html
(except) in my derivation, we have an interesting factor of [math]2[/math] showing up.
The reason why this could have important relevance, (in this derivation), is because [math]2Et^2[/math] has been set equal with [math]Mr^2[/math]. Anyone even with a slight knowledge of ''inertia physics'' will know that [math]Mr^2[/math] is in fact the rotational inertia of a body.
(and just to add)
Here is a paper by Schwinger who was noted by lloyd motz in his own derivation of [math]\sqrt{G}M[/math] (the square root of the gravitational charge)  an interesting read on similar approaches by Lloyd and a direct importance with my own work
http://wdxy.hubu.edu...10535154942.pdf
I also derive a generic integral form of
[math]\frac{GM^2}{\hbar} = \frac{\int \sqrt{Fds}}{\sqrt{\frac{1}{v}} \int \sqrt{Fdt  m_0}}[/math]
To define the inertia of a moving body where [math]M_0[/math] is a rest mass term. This would mean then that the gravitational charge can be computed in terms of a rest mass given as (or understanding it with terms of rest mass) as:
[math]GM^2 = \hbar(\frac{\int \sqrt{Fds}}{\sqrt{\frac{1}{v}} \int \sqrt{Fdt  m_0}})[/math]
Albeit, it looks like a complicated mess.
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I finished the book well, because i understood the theory briefly before i read it, i can't understand the old theory that dominated the physics in 1800s the ether wind theory. So can some good people help me understand it ?
I didn't really get the Mach's principle , ether wind theory, and in the book says so much how stuff can't travel faster or at speed of light, but a pair of huge scissors can because it is moving on a geometric point, i didn't get that. It was kind of confusing for me to read a English book because I'm Chinese.
and last question, in the book it stated that in a space ship traveling at high speed, lets say 50% speed of c. lets say the ceiling and floor of the rocket is parallel, and a light bulb's from ceiling is going down strait. and reflect up. and it said 2 observer is different. The guy inside see a light go down and up  just like this, but someone out side not moving will see the light go like this \ and reflect up / Yes i understand because the space ship is moving at the same time, but it is because that the time is passing slower for him but the light is constant so this is possible or opposite ?
Someone else started a thread on Aether Theory.
Many people said it was ''proven wrong''.... That is not true. The old classical theory of Aether was proven wrong  this does not mean an Aether does not exist. In a recent conversation with someone, it was made apparent to me that there could be a ''quantum Aether.''
In your case, the wind Aether, is like a dragging effect on time, much as a syth rakes through an old mans crops. An object in the classical version would do much the same thing  it would plow through spacetime dragging the background energies with it. I believe it is this type of ''wind'' that was hoping to be observed. The idea came about from the Luminiferous Aether and it described the motion of particles in a medium of light particles.
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Sometimes intended meanings can be ambiguous when made by anyone. I just wrongly thought I could detect a foreign language influence.
Moving on: I don't think any such system can be stopped or suspended, only greatly slowed down close to absolute zero, or behavior modified by external influences and measurement. All systems and matter have a ground state of energy. Accordingly no lower state can be achieved. One of those ground states is particle spin which involves motion. Another ground state is Zero Point Energy.
There is no universally accepted theory of time. I expect that in the future some of the more complicated time concepts today will be greatly simplified. Time, with the absence of such convolutions, might be simply defined as an interval of change. All concepts and definitions of energy and motion involve an interval of time, usually the second.
//
When it comes to evolution, it could be stopped, till the end of time if you had a perfect type of measuring device capable of making periodic measurements on a system  such as the induced type I spoke about between myself and Swansont concerning weak measurements on a system. Basically, if you make slight observations in a duration of ''time'' you can stop an atom radiating away its energy  that halts any evolutionary processes involved with the changing of your system  the zeno effect was predicted and proven to be completely accurate within the bounds of quantum mechanical predictions. You may think of it as a success of quantum theory.
You keep going back to ''ground states''  this is not applicable here. Yes it is true, you cannot ''freeze an object to absolute zero''. This is because absolute zero is a limit which can never be obtained  there is always a motion of [math]\frac{1}{2}\hbar \omega[/math] left over  the energy of a simple harmonic oscillator never diminishes.
But what I speak of, is something completely different, separate to socalled ''temperatures'' of system.
Now, there certainly is no universal accepted theory of time, but we certainly know a few things  things where Newtonian views of time simply do not hold, such as a flow to time. For instance, if time flows, what is it flowing relative to?
Naturally, consciousness is not a physical phenomenon per se, but rather a subjective experience. Some people then, might say that time flows relative to us, but this cannot be the right approach, rather it would be simpler saying that our experience of time passing is what gives us the ''sense of time'' flowing from one experience to another. Objects and events outside of our minds have no evidence whatsoever that time is a real objective feature of the world  we project our experiences of the world unto it. The world is scrutinized by our subjective sense of it, our attentively probing reality is scrutinized by our observations and measurements. Our observations only make sense therefore, because we have a sense of time. Remove time and we'd have no sense of ''passing events'' just as much as the objective world would care not less about a real existing time.
( Let me add a bit more about these observational properties you are hung up on to clear the water perhaps?)
An atom can remain it's ground state because you make observations on it over periods of time. This can keep the atom from reaching higher energy levels by suspending its quantum evolution.
A system cannot be frozen to absolute ground states, because it will always keep a measure of kinetic energy about it. Ground state and absolute ground states to me is the language I would use to solve this little problem.
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Here's a good paper on electromagnetic mass  a topic spoke about in the OP.
http://ivanik3.narod.ru/EMagnitizm/JornalPape/ParadocsCullwick/hnizdo_ajp_65_55_97.pdf
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No, you can't.
Bell's theorem says that there are no local hidden variables. This means any viable interpretation of quantum mechanics either has to throw out realism or locality. Realism: The Moon is still there when no one looks at it. Locality: No spooky action at a distance. So what if the "correct" interpretation of QM is to maintain realism? Wouldn't that imply that FTL communication might be possible?
The answer is no. There are a number of "no signaling" theorems that start from a basic set of assumptions to show that FTL communications cannot happen. Every viable interpretation of QM obeys those assumptions, even those that reject locality. So even if the universe truly is nonlocal, FTL communication still can't happen.
There was an experiment recently which might solve this dichotomy... I'm currently looking for it. It involved entangled photons.
The short version (which only I can remember) is that particles when not being observed where showing up in places they shouldn't have been.
The moon is a macroscopic system  just as is Schrodinger's Cat. I don't believe the cat will show up in a different place nor the moon, but maybe realism should be cut up into microscopic realism and macroscopic realism  in which case, I'd throw out the microscopic realism.
found it:
http://www.economist.com/node/13226725
I read the paper a while back as well, it was quite technical.
I suppose if the realism strictly depends on whether the object is still ''there''.... or still ''exists'' is a big difference. If the object is not exactly ''there'' any more, but is in a different place, it puts a new slant on things. If the position of an object does not matter in realism, then long it lives.
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There is no integral
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Middle of the universe
in Astronomy and Cosmology
Posted
I didn't compare them.
Anyway, the only way you can have a center to the universe is by saying that every point on the spacetime map was the center.