Theory of Everything?

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As I understand it, Newton was making a metaphysical claim and used the term “absolute” to signify that “absolute space” is real regardless of what physics did or didn’t have to say about it. I don’t believe the aether represented the concept of absolute space. It was merely meant as a possibility of an actual physical substance of space.

If so, rejecting the aether is not the same as rejecting absolute space. And therefore, It seems to me, to reject absolute space would require a philosophical objection to it’s existence, which, at the time, is what verificationism would have provided.

OK. I see your point. That’s what we now recognize, that most all of modern science is based on things which cannot be verified because it’s based on inferences from supporting evidence, not from direct verification.

But that wasn’t the case back in the first half of the 20th century. Logical positivism, which has it’s roots in verificationism, was in fashion up to the middle of the 20th century. It wasn’t until sometime in the 40s that it began to be called into question because of, among other things, the point you raise, which is one of the reasons why it was finally rejected.

So though a valid point, that wouldn’t rule out Einstein being influenced by verificationism at one point or another, at least in his earlier years. And there’s pretty good evidence, at least when it comes to SR, that it very well could have been the case. Ernst Mach held a positivist position, and it seems according to Einstein himself, Mach greatly influenced Einstein in his formulation of SR.

Absolute spacetime is assumed in GR?

As I stated above, I think Newton’s concepts of absolute space, time, and simultaneity are meant as fundamentally ontological. If so, for Newton they would exist regardless of whether or not they could be demonstrated in some way by physics.

This is what’s confusing to me. Theory is explanation. An explanation is not descriptive. Equations are descriptive. How can an explanation affect a description?

When I say Theory of Everything, I’m talking specifically about theory, i.e., explanation. However, I get the impression you are talking about both explanation and description. Is that possibly where the disconnect is?

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No, I mean that IF it is possible to assume absolute spacetime and simultaneity in GR, it will be just one additional unobservable. No reason to drop it due to verificationism if verificationism doesn’t drop the other unobservables.

I don’t care about SR or Einstein’s thoughts on SR. SR is false, and Einstein himself had moved beyond it with GR. We’re talking the real world now, so use GR not SR.

Have you considered why is it possible for Newton to claim that absolute space is purely ontological? The reason Newton can do this is because his theory can be formulated with or without absolute space. This is no longer possible in GR. The absolute spacetime and simultaneity has moved from the purely ontological to actual physics.

What? This makes zero sense to me. I think you’re using weird definitions for words. Regardless,

You proposed a theory of everything that can unite gravity and quantum mechanics. The problem in unifying them lies in their MATHEMATICAL DESCRIPTIONS, their THEORY according to physics. Therefore, if you want to change their ontology without affecting the mathematical descriptions, you CANNOT unify them.

Edit: @Jim what you need to do to convince me is to give me an “explanation” of the equations of GR (“mathematical description”, which rests on observational evidence) that uses absolute spacetime and simultaneity.

Edit Edit: @Jim maybe this will help to answer.

(Note: throughout, while I myself won’t use it this way, I will use the word “Explanation” the way you are using it, as a normative, as opposed to descriptive, reason of why things happen)

I have a box that gives me a number everyday. The numbers I got so far on day 10 is:
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
These are the observations. The mathematical description of these observation is:
N_I = 2 \times I for at least I\le10
Where I is the number of day.

Explanation one:
Inside the box is a frog that writes these numbers for me. They write the number in ascending order from 0, but this frog does not like to write odd numbers.

Explanation two:
Inside the box is a frog that writes these numbers for me. They write the number in ascending order from 0, but this frog does not like to write the following set of numbers: 1,3,5,7,9,11,13,15,17,19.

These two explanations both reproduces the equation
N_I = 2 \times I for at least I \le 10
In accordance to the experimental results.

On day 11: I get the number 21. Now it is clear that Explanation 1 is no longer consistent with the observation, while Explanation 2 is still consistent with the observation. Indeed, following through the experiment for 30 days, it turns out that the numbers that come out can be mathematically described as a piecewise function:

N_I = 2 \times I for I \le 10, and N_I = I for I>10, for at least 10 < I \le 30.

While this piecewise function, a single mathematical description, can be reproduced by multiple explanations, such as explanation 2 and this new explanation 3 (below), it is no longer consistent with Explanation 1.

Explanation 3:
Inside the box is a frog that writes these numbers for me. They write the number in ascending order from 0, but this frog does not like to write the following set of numbers: 1,3,5,7,9,11,13,15,17,19,50.

A single mathematical description, like the piecewise function given above, whose truth rested on experiments, can be given multiple explanations. But that does not mean that all explanations can validly explain it, even if the explanation can validly explain the function for a limited regime of validity (I \le 10). Note that if this is not true, I can come up with any random explanation and have them be valid. Observations produce equations that serves as the MATHEMATICAL DESCRIPTION of a phenomenon. However, an “explanation” also produce an equation based on its assumption. If these two equations match, then that explanation is valid. Otherwise it is invalid.

What happened to Explanation 1 is what happened to Newtonian’s absolute space, time, and simultaneity once enough observation is gathered to favor GR. There is no “explanation” of the equations of GR that uses absolute spacetime and simultaneity. If you think there is, please offer them now.

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SR is false and Einstein moved beyond it? OK. Or are you referring to what I’ve read that he tried and failed to get GR and SR to mesh with each other?

Because it just happens to be an ontological claim?

Why is that the case for NM and not for RM? Is it because RM is tagged as a relativity theory and therefore by humanly imposed restrictions the equations are off limits to be used in any other fashion? Or is there some purely mathematical restriction that just doesn’t allow for it?

I’m a bit confused about this. Ontology is metaphysics and by definition outside the realm of physics. As I understand it Newton framed his claim of absolute space as metaphysical. So how can a metaphysical claim move from being metaphysical to physical? I understand that the aether is a physical claim, but I don’t think absolute space was ever meant as such.

I’m assuming a theory is just the explanation. It seems maybe you include both explanation and description in the definition. Could that be the confusion?

I would agree that observations produce equations which serve as mathematical descriptions of the behavior of a phenomenon. And I understand that equations can be conceptually formulated from explanations and make predictions that can be verified by observation.

However, with explanation, the only role I can see it playing in producing an equation is to conceptually facilitate the formulation of an equation since there can be many empirically equivalent equations “correctly” describing the behavior while at the same time having been conceptualized using completely different explanations. I don’t see how explanation can be interconnected causally to the equations.

I’m sorry, but I suspect there are some problems with this analogy The main problem being the explanations of what it is are assumed to be interconnected with descriptions of what it does. And in the end it seems to me what is ruled out is the associated description that doesn’t match the observed behavior, not the explanation itself.

In order to rule out the explanation because of the failure of the description, what seems to me needs to be shown is that there is a causal connection between the explanation of what some unobservable thing is to the description of what it observably does. And we know that several empirically equivalent descriptions that “correctly” describe the same observed behavior can each be conceptually based on totally different explanations.

So based on that, assuming that there is only one true explanation, that seems to suggest that there is no causal link between description and explanation. This is without even taking into account that both are abstractions of the observations, and therefore, logically speaking, are both causally effete.

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This is exactly what happened to Newtonian absolute frame once enough data was gathered. If you have a problem with explanation 1, then you have a problem with Newtonian absolute frames. It turns out that the existence of absolute frame (what it is) is connected to the observables (what it does).

Edit: @Jim as an example of absolute frames coming into play in observables in GR, let’s take classical cosmological spacetimes that obey the BGV theorem that you like so much. The BGV theorem states that in classical GR, in some finite past spacetime can no longer be split into 3 spatial and 1 time dimension - thus it becomes impossible to define a plane of simultaneity, let alone a plane of absolute simultaneity.

So you get to defend one, absolute spacetime or the BGV theorem. Take your pick.

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This is only true when your intuition is guided by Newtonian mechanics.

If your intuition is guided by Einstein’s field equations, then the idea is not at all absurd.*

The problem for non-physicist humans like you and me, Jim, is that our intuition is honed by our upbringing in a world in which Newtonian mechanics are successful and sufficient. As long as we’re not building power plants and thermonuclear bombs.

My $.02,
Chris

*I don’t understand Einstein’s field equations; I accept them because because physicists and engineers have built working bombs and power plants based on EFE.

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Theory of everything. Thinking out loud I will suggest that we stagger the creation of space, time, and matter in our discussion of the singularity. If for instance, space and matter were created first (or just space first or just matter first), it may have causally and secondarily brought time into being. Perhaps our equations need to stagger the entrance of the dimensions at the moment of creation rather than always seeking a simultaneous eruption.

That may help redefine the singularity. Perhaps it would begin to take on a real mathematical description. And if the start of everything was “bumpy” or discrete, then the gaps in our physics may not be such an enigma. Perhaps if some brilliant mind would run GR and the QFT backwards in time and forced the singularity not to exist no matter how much it tried to. How are space and matter defined a Planck moment before time exists?

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It may be we’re talking past each other once more. :slight_smile: Let me try another angle. Absolute space is sometimes referred to as “a God’s eye view.” Is it possible through physics to measure the entire universe or observe it in one go at any point in time? Obviously humans don’t have that capacity.

That would suggest that whether or not absolute space exists is not a questions that can be determined by physics since physics at it’s core relies on things like observation and measurement. So at least at this point in time, physics is confined to relative space due to human limitation, not necessarily because absolute space doesn’t exist.

Metaphysics, on the other hand, at it’s core relies on reason, which seems at present to be what’s left in regards to human investigation into this matter. Is it possible through metaphysics to get a sense of whether or not the existence of absolute space is a reasonable concept?

I believe so. And as far as I can tell, it’s still an unresolved issue that needs further investigation. I, for one, am of the opinion that the non existence of absolute space, i.e., only observer relative space, would entail that space is not an independent reality but a human observer dependent reality.

And from that, it seems to follow, that there must exists more than one reality, at least as far as space is concerned. But that creates a lot of problems in making sense of reality, at least that’s how it seems to me. It seems to make a lot more sense to me to assume absolute space when it comes to making sense of reality.

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This is not true. It was thought as such by Newton, but as modern measurements becomes more advanced than Newton ever think of, it turns out that the presence of an absolute spacetime is something that affects measurements.

As I mentioned before (and you completely ignored), an absolute spacetime requires that the universe can always be split into 3 space and 1 time dimensions, in contrast to the conclusion of the BGV theorem. Whether the universe has a singularity or not (as per the BGV theorem), is an observable, and depends on whether there exist an absolute spacetime or not.

By the way,

This position is called manifold un-substantialism, and a completely valid interpretation of general relativity. General relativity does not require spacetime to be an independent reality.

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There are some puzzling statements here. First of all, as far as I know spacetime is just a concept. It has never been observed. But when you talk of absolute spacetime, I assume you’ve got something different in mind than Newton’s absolute space. Is that right?

And I’m wondering what you mean by the presence of absolute spacetime? Since you seem to be saying it doesn’t exist, how can it be present? And how could something that doesn’t exist affect a measurement? Wouldn’t it need to exist to affect a measurement?

Or do you mean that equations that involve an absolute spacetime don’t give the correct results?

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This.

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OK. But I’ll return to the point I’ve been trying to get across so far unsuccessfully. Equations describe observed reality, they don’t determine it. They are subject to verification through the observation, not the other way around.

And likewise observation is what provides supporting evidence to infer an explanation of what the unobservable reality is that underlies the observation. So trying to argue that the existence of an unobserved reality can be shown to be true or false by resorting to equations has no basis in logic, as far as I can tell.

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Have you done any science in your life?

The way we see whether a scientific theory is right or wrong in the quantitative sciences is the following:

  1. From the theory (which include unobservable realities) an equation that predicts an observable is derived
  2. From the experiments, an equation that describes the observable is obtained
  3. If these two equations match, then the theory is vindicated

From theories that include absolute spacetimes, an equation for an observable is derived. This equation does not match the equation for that observable obtained from experiments. Therefore, experiments have so far been evidence against absolute spacetimes.

Regardless, you are still shooting your own foot. Your original reason for starting this thread is to have a theory of everything that can combine the very large and the very small. They are incompatible at the level of mathematical description, not unobservable realities. As you claim that absolute spacetime is only at the level of unobservable reality, then it will not help you unite anything in physics.

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And back to my point that there is an unrecognized distinction between description and explanation. Just because a description is verified has no bearing on the explanation. It’s the observation that the explanation gets it’s warrant from, not the description.

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Maybe you should give an example. Let’s say we have two statements:

  1. The Earth is flat
  2. The Earth is round

An an observation:
The total angle of a triangle made on Earth is >180 degrees

For both of these statements, what is the description, what is the explanation, and how does the observation work to say that statement 1) is wrong?

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From what I can tell you’ve got two possible explanations, i.e., theories, and one observation/measurement. Don’t see any description. Am I missing something?

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Ok, how do you get the observation to say that one of those explanations are wrong then?

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Well, based on the present information, and assuming the measurement is correct, then one could infer #2 is correct.

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How do you infer #2 is correct? The statement “The Earth is round” by itself says nothing of the total angle of any triangles.

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OK. I see where the description comes in. If I’m not mistaken, from what I remember of high school geometry, a flat triangle would = 180 degrees.

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That’s right, we have two theories,

  1. The Earth is flat
    From this is derived the description: “total angle in a triangle made on Earth is 180 deg”
  2. The Earth is round
    From this is derived the description: “total angle in a triangle made on Earth is is >180 deg”

We compare the descriptions that is derived from 1) and 2) with the observation:
“The total angle of a triangle made on Earth is >180 deg”

The description derived from theory 1) does not match the observation, so this observation is evidence against theory 1).

This is the exact same case with absolute spacetimes. The theory produces a description that does not match the observation.

Indeed, I chose this “shape of the Earth” example deliberately, as this experiment (seeing that angles in a triangle sums to 180 deg or not) is the same done by the Planck satellite to learn of the “shape of the universal spacetime”. See the paper: http://inspirehep.net/record/1682902?ln=en

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