Science Forums 2

[AnssiH]

So far your only objection to the current standard definition of space and time as dimensions is that other less useful interpretations exist. You apparently don’t want to advocate any of those - you’re just pointing out that they’re there.

Obviously I don't want to advocate the ontological reality of any of them, as that would be a completely arbitrary choice. A mere belief. It's like the argument of "fairies vs. elves".

If you want to rearrange the laws of physics and fundamental variables that get put in them then go ahead. If it is consistent like our current understanding and makes similar or better predictions then I’m all for it.

Yes, I'm glad you see things that way at least. You might be interested to follow DD's analysis because it sheds a lot of light on exactly this issue. Apparently one reason why people have not reviewed his work very much is that many people are unable to see that the definitions in their worldview really can be "rearranged" into a different but predictionwise equally valid model, much like algebraic equations can be rearranged. (And much like it is with algebra, you cannot just change one term in the equation and still keep it valid; you must change the whole thing into a different self-coherent set of definitions)

They cannot see this fact because they do not recognize how they investigate reality completely from within their valid worldview. Every day, they see the effects of the entities they believe to exist, and cannot trivially comprehend how could it be said they do not exist. They see those effects because that is how they interpret their sensory data. But those entities simply do not exist in different valid models, because they are not defined in that raw data that is to be explained. The noumena that gives rise to such definitions, can be considered "real". The definitions by themselves are immaterial references to those patterns. Including "gravity", "time" and "space". Simple as that.

You wonder why I’m bringing up physics when you say we are trying to figure out what makes physics models valid. Humm...

When you bring up physics, you are investigating the possibilities from within your worldview. There is not much wiggleroom there, as that is like investigating what single terms can be changed in an algebraic equation without making it invalid.

You need to begin from considerations of how some raw data stream could be defined in valid manner & without making undefendable assumptions about its ontological reality.

Either change is completely synonymous with movement

And when you investigate this from the point of view of defining undefined raw data, one particular issue that arises is that you need to somehow assume that certain features of that data are referring or "caused" by the "same object" from one moment to the next (and once again many different ways to define "objects" exist. For one that differs very much from Standard Model, see that Milo Wolff's definition of spherical standing waves).

"Movement" requires one to identify some pattern as the "same object" (i.e. there must be a definition for "object" that is said to be "moved")
In "change" one object disappears and another appears.

Note that we are very much talking about epistemological concepts; concepts that are used to understand reality. There is no way to probe the ontological reality of either assumption.

And that is why "change" is synonymous with "movement" only in your personal worldview. Otherwise such an assertion cannot be defended.

On the contrary, it implies that string theory may not have any basis in reality. Multiple string theories have made identical predictions with different theoretical structure. Which is correct to reality?

It implies none of the models - that make the identical predictions - may not have "any basis on (ontological) reality". Including Standard Model. You insist certain things in your own worldview are "real", while apparently you are able to question the ontological validity of some models. Like Overdog is saying, you are very much operating on beliefs.

Your comment also implies you think "the simplest" model must be the one that has got "basis on reality" while others don't. That is exactly the kind of ontological assumption you should not make. First, "simplest" by what criteria? And second, why on earth would reality be "like" the simplest way to describe it?

It is like asking people, who don't know how combustion engine works, to explain what is it that makes a car propel itself onwards, without looking what is inside. So the person who comes up with the simplest explanation is also correct to how that car works?

It’s in fact not even correct to say that both string theory and the standard model can’t both be right. They may well be. Would you say newton’s laws of gravity and Einstein’s GR can’t both be right? Yes, they can both be right and your description above is wrong.

Like I've said many times, they are all "valid", as in they make correct predictions about the raw data. There can always exist multiple valid models that explain ALL of our past; for all we know they are "right". But we also know they are not all "ontologically correct", as they explain the same phenomenon with different concepts.

Good understanding of epistemological concepts reveals that with very high likelyhood, none can be "ontologically correct", that sort of question is moot. That realization immediately lifts all valid models on the equal footing. And there's no reason to argue about elves and fairies.

What other interpretations [of relativity] are possible?

I've already mentioned few in post #448.

The assumption that reality is a static spacetime block is just one interpretation.

Another would be that reality does not exist in any definite "now-state" before it is being observed.

Or one could imagine each inertial frame is part of a multiverse, i.e. we switch to a different "space" (where the "now"-states really exist differently from each others)

Am I right to assume that you see spacetime as a static block where future and past exists all the time, and you therefore assume your "consciousness" is the only thing that is actually "moving" through that sapcetime? Don't worry, I am not here to argue about whether reality is like that; I believe that is a self-coherent way to see things. But I am somewhat worried if that really is the only interpretation that you think is possible?

How we ‘model’ gravity in the ‘theory’ of general relativity doesn’t make it any less real. If mass curves spacetime and we see attraction between masses then gravity refers to that curved spacetime. Did you miss my point that there are real processes of the universe that we can’t touch?

Did you miss my point of how we are the ones who define things and thus decide what constitutes a "process". You claim that your use of the word "real" does not mean you suppose it's more than our definitions of some unknown reality, yet you are ready to point out that "string theory" may not have any basis on reality. Well, it has got exactly the same basis on reality as any model of "gravity"; it explains the patterns we see.

It would be good mental hygiene for philosophy to realize why it has done so poor a job of informing science.

It has done a lot of good. For one, Einstein did need to investigate his "common sense beliefs" - step outside of his own personal worldview - to realize that it is indeed completely valid to define "simultaneity" - against all common sense - as relative to the direction of movement. Of course initially he had to battle a lot of people who were too immersed in their personal worldview to understand how such a definition could be valid.

Einstein did not, as far as I know, make any strong implications about the ontological reality behind the (predictionwise) validity of such a definition. I know he definitely did not like Minkowski's spacetime interpretation at first, albeit he did come to think of relativity in those terms later. (On the other hand he has also referred to things like "space" and "time" and "force" as "concepts", so I suspect he was trying to avoid the ontological questions of his models) And now we are in a situation where spacetime interpretation is quite common, and very many people are too immersed in it to see how different definitions are indeed quite possible.

Here's another fun fact about the history of physics. Ludwig Boltzmann was the person who managed to model the behaviour of gases in terms of kinetic behaviour of "atoms" and "molecules". Although that model was predictionwise valid, the scientific community at the time was too immersed in their personal worldviews to believe such things as "atoms" or "molecules" could really exist. Boltzmann become so depressed by the ridicule from the scientific community that he eventually hanged himself. (Before scientific communite became to accept his model... ...of course immediately assuming model = reality)

These days of course many people are absolutely convinced "atoms" and "molecules" are ontological things by themselves. All I can say is, if a model makes valid predictions, it can be used! Rest is belief. That should be the contribution of philosophy to science.

Other way around, one thing where physical models are helpful for ontological considerations is that when you think about a lot of alternative models and their interpretations, you can see how different self-coherent definitions really are possible. Such is the case with QM also. And different ontological interpretations of relativity imply different ontological interpretations for QM. For one, static spacetime implies transactional interpretation for explaining Bell Experiments. You (and everyone else thinking about "time") might find this interesting;

Quantum mechanics and spacetime

Also Bell Experiments are interesting in that they by themselves imply absolute simultaneity; they can motivate one to interpret relativistic relationships in a manner that makes absolute simultaneity ontologically real. And yes, against all the intuition that you have inside your personal worldview, such interpretation indeed is completely possible.

In the end, I should reiterate that the one view on relativity - that I find quite reasonable and if DD's treatment has no fata flaws can be logically proven - is that the relativistic transformation between inertial frames is an unavoidable consequence of how entities can be defined in any "raw undefined data", if you do it self-coherently and without undefendable assumptions. It took us a long time to end up with relativistic transformations in our physics models because we were so slow to drop off those "undefendable assumptions", one by one, from our models.

That, if anything, would be a fair contribution of epistemology & ontology to science. Too bad most people are too immersed in the validity of their personal worldviews to investigate such possibility

-Anssi