Is foundational physics stuck?

[swansont]

1 minute ago, DanMP said:

There is no experimental data?!? So there is no experimental data to back GR? 😀 What in the world are you talking about? 

GR is 100 years old. It’s established physics, not new foundational physics, which is what this topic is about.

[studiot]

1 hour ago, DanMP said:

The fact that current theories are not actually explaining the reality. Can you explain what a field is and how exactly a force is transmitted at a distance? Can you explain the invariance of c? Can you explain how a mass is warping spacetime? And no, I'm not asking how the model works, I'm asking what and how is really happening. 

 

Also, in the string theory, why the strings are vibrating?

 

Anyway, it seems that I'm not the only one to expect more, better, model

Trying to be a smart alec about this is really counterproductive as well as being somewhat insulting.

You clearly haven't read many of my posts or you would know that I don't subscribe to the string hypothesis.

As a mathematician I would ask if you have any real idea what a field is because my idea is very different from yours and furthermore there are many posts in many thread here where I have explained my pov.

What is there to 'explain'. Theory and observation have coincided ever since the idea of a speed limit was first mooted and Maxwell suggested that light travels at this speed from his equations.

Well since mathematically warping is the wrong word no I don't.

 

This leaves only one question that of action at a distance, which I agree with you has yet to be explained by any hypothesis.

Edited Wednesday at 07:56 PM by studiot

[swansont]

1 hour ago, DanMP said:

The fact that current theories are not actually explaining the reality

Physics tells us how nature behaves. Its job isn’t to explain reality. i.e. there’s plenty of stuff in physics that are calculational conveniences and don’t actually exist. (field lines and phonons to name two)

[studiot]

12 minutes ago, swansont said:

Physics tells us how nature behaves. Its job isn’t to explain reality. i.e. there’s plenty of stuff in physics that are calculational conveniences and don’t actually exist. (field lines and phonons to name two)

Totally agree, but more to the point, what is this 'reality' ?

Surely we can only offer our best effort to measure something and say

If you do this in this particular way you will find the following happens.......

[DanMP]

1 hour ago, swansont said:

GR is 100 years old. It’s established physics, not new foundational physics, which is what this topic is about.

Any new theory must be, first, in agreement with all the old experimental data, and then to predict things that can be experimentally tested afterwards. 

 

1 hour ago, swansont said:

Physics tells us how nature behaves. Its job isn’t to explain reality. i.e. there’s plenty of stuff in physics that are calculational conveniences and don’t actually exist. (field lines and phonons to name two)

Yes, but this leaves room for new theories, theories that can explain more. Probably it's impossible to explain everything, but we can do more than we did so far. 

 

1 hour ago, studiot said:

You clearly haven't read many of my posts or you would know that I don't subscribe to the string hypothesis.

As a mathematician I would ask if you have any real idea what a field is because my idea is very different from yours and furthermore there are many posts in many thread here where I have explained my pov.

Yes, I didn't read many of your posts, so I really don't know/remember your pov. Anyway, my questions were not directed to you or any person in particular. I just explained why I think that it is still room for new foundational theories. 

My understanding of fields is not good. Perhaps that’s why I don't like them.

 

1 hour ago, swansont said:

Can you give some examples of modern physics models that are “physical”?

Unfortunately no. In fact this may be the sign that we climbed in the wrong fruit tree 😀

Edited Wednesday at 09:05 PM by DanMP

[swansont]

40 minutes ago, DanMP said:

Any new theory must be, first, in agreement with all the old experimental data, and then to predict things that can be experimentally tested afterwards. 

Yes. But the “new” part is…new. Newtonian gravity did not give us GR. 

40 minutes ago, DanMP said:

Yes, but this leaves room for new theories, theories that can explain more. Probably it's impossible to explain everything, but we can do more than we did so far. 

Yes. Nobody has said there isn’t new physics. But you haven’t described a valid path to get there.

40 minutes ago, DanMP said:

Unfortunately no. In fact this may be the sign that we climbed in the wrong fruit tree 😀

So it’s not part of theory, yet it’s a requirement of yours? Something that doesn’t exist and you can’t/won’t define or describe beyond the name? You might as well say we need splunge.

[studiot]

2 hours ago, DanMP said:

Any new theory must be, first, in agreement with all the old experimental data, and then to predict things that can be experimentally tested afterwards. 

'All' is too bold a statement, which if true would have precluded many discoveries in Physics.

For instance the discovery of the nucleus by Rutherford.

Quote

According to the accepted atomic model, in which an atom's mass and charge are uniformly distributed throughout the atom, the scientists expected that all of the alpha particles would pass through the gold foil with only a slight deflection or none at all. Surprisingly, while most of the alpha particles were indeed not deflected, a very small percentage (about 1 in 8000 particles) bounced off the gold foil at very large angles. Some were even redirected back toward the source. No prior knowledge had prepared them for this discovery. In a famous quote, Rutherford exclaimed that it was "as if you had fired a 15-inch [artillery] shell at a piece of tissue and it came back and hit you."

Or the discovery of the pattern of reversing magnetic stripes in the rocks at the bottom of the atlantic by Morley, Matthews and Vine.

There have been many such breakthrough experiments and insights in scentific history.

 

 

[swansont]

13 hours ago, studiot said:

'All' is too bold a statement, which if true would have precluded many discoveries in Physics.

For instance the discovery of the nucleus by Rutherford.

How so? The discovery of the nucleus wasn’t a new theory, it was an experiment. Any new atomic theory afterwards had to be consistent with the data from before (e.g. positive and negative charges) and the new one (positive charges in a very dense collection)

Rutherfords discovery was not precluded in any way.

[DanMP]

17 hours ago, swansont said:

Yes. But the “new” part is…new. Newtonian gravity did not give us GR. 

I wrote that any new theory must be in agreement with all the old experimental data, in other words to be consistent (compatible or in agreement) with all that we observed and measured before (in that particular field). I really don't understand why your reply is "Newtonian gravity did not give us GR". Newtonian gravity and GR are theories, not experimental data. Experimental data does not belong to a theory. Ok, GR proposed new experiments, that were confirmed. This is why I wrote "and then to predict things that can be experimentally tested afterwards".

To give an example, MOND theories are able to explain the rotation curve of a disc galaxy, and more, but, being gravitational theories, they must also explain gravitational time dilation and gravitational lensing.

 

17 hours ago, swansont said:

But you haven’t described a valid path to get there.

I proposed to reassess the things more or less explained long time ago, like the invariance of c, having in mind DM, etc., as opposed to "randomly and blindly groping in the dark by inventing maths that don’t seem to be motivated by any real-world data points, hoping to just stumble across that next breakthrough".

 

17 hours ago, swansont said:

So it’s not part of theory, yet it’s a requirement of yours? Something that doesn’t exist and you can’t/won’t define or describe beyond the name? You might as well say we need splunge.

I can describe what I meant when I suggested to focus more on actual physics. I meant to work with real elements/particles (as opposed to virtual/invented), to define their behavior and how they interact, and then make computer simulations in order to check and refine the model.

GR is purely geometric and the fields are like Greek gods (they are invisible but very potent, they interact with each other, they have well defined tasks and magic abilities).

The situation in physics today may be similar to the one in medical science in Robert Koch's (one of the main founders of modern bacteriology) time. Before him, it was believed that illnesses are caused by bad air or by gods/demons (invisible, invented entities, like the fields are). Koch discovered bacteria and showed that not invisible, invented entities are causing the illnesses ...  I think that DM particles can be used to explain things better than the fields we invented and the abstract geometry we created.

 

2 hours ago, swansont said:

Any new atomic theory afterwards had to be consistent with the data from before 

Yes, you finally got it (any new theory must be in agreement with all the old experimental data).

 

2 hours ago, swansont said:

Rutherfords discovery was not precluded in any way.

Yes.

 

16 hours ago, studiot said:

'All' is too bold a statement, which if true would have precluded many discoveries in Physics.

I meant all experimental data that concerns the new theory/model, not all the experimental data in all science, nor the previous interpretations of experiments.

[swansont]

29 minutes ago, DanMP said:

I wrote that any new theory must be in agreement with all the old experimental data, in other words to be consistent (compatible or in agreement) with all that we observed and measured before (in that particular field).

Which I agreed with. (that’s what the “yes” means)

29 minutes ago, DanMP said:

I really don't understand why your reply is "Newtonian gravity did not give us GR". Newtonian gravity and GR are theories, not experimental data. Experimental data does not belong to a theory. Ok, GR proposed new experiments, that were confirmed. This is why I wrote "and then to predict things that can be experimentally tested afterwards".

GR did not come from Newtonian physics. GR was math and your position leaves that avenue closed. It would require Eddington’s experiment happen on its own, without being motivated by theory, to spur new theory development.

 

29 minutes ago, DanMP said:

I can describe what I meant when I suggested to focus more on actual physics. I meant to work with real elements/particles (as opposed to virtual/invented), to define their behavior and how they interact, and then make computer simulations in order to check and refine the model.

A simulation requires that the math already exist, and real particles limits us to what we’ve already discovered.

How does that get us any new physics?

 

[Markus Hanke]

14 hours ago, DanMP said:

I proposed to reassess the things more or less explained long time ago, like the invariance of c

How do you propose to reassess this? The numerical value of c is a function of the permittivity and permeability of the underlying medium (this was known before Einstein), which of course don’t change just because some observer happens to be in relative motion wrt to some reference point. If they changed, he wouldn’t be in the same medium any longer, which creates physically unresolvable paradoxes. 

I propose that c is invariant because the universe cannot contain such unresolvable paradoxes. 

[DanMP]

23 hours ago, swansont said:

GR did not come from Newtonian physics. GR was math and your position leaves that avenue closed. It would require Eddington’s experiment happen on its own, without being motivated by theory, to spur new theory development.

I don't quite understand what you mean, but the fact that "GR did not come from Newtonian physics" shows that a new theory may have a completely different approach. GR geometric approach was needed because at the time it was adopted it was not possible to find another, better one, because they didn't know about DM.

Usually, when you feel that the way you took may not be the good one, you simply go back a bit and try another route. This was/is my suggestion, to make a step back and retry.

 

23 hours ago, swansont said:

A simulation requires that the math already exist, and real particles limits us to what we’ve already discovered.

How does that get us any new physics?

The simulations I envisioned require simple math and real particles. I don't know about you, but I consider DM particles as real, as opposed to virtual or invented. Their proprieties cannot be found directly, so the alternative is to imagine/define a model and test it. Something similar was done for quarks.

 

10 hours ago, Markus Hanke said:

How do you propose to reassess this? The numerical value of c is a function of the permittivity and permeability of the underlying medium (this was known before Einstein), which of course don’t change just because some observer happens to be in relative motion wrt to some reference point. If they changed, he wouldn’t be in the same medium any longer, which creates physically unresolvable paradoxes. 

I propose that c is invariant because the universe cannot contain such unresolvable paradoxes. 

I'll explain it soon (within a week). Now I really have to go.

[swansont]

1 hour ago, DanMP said:

The simulations I envisioned require simple math and real particles. I don't know about you, but I consider DM particles as real, as opposed to virtual or invented. Their proprieties cannot be found directly, so the alternative is to imagine/define a model and test it.

Simple math is still math. Simulations are not magic. The result isn’t conjured. They are math, and the result is from computations

1 hour ago, DanMP said:

Something similar was done for quarks.

Yup. With math.

 

[joigus]

What simulations do is take a mathematical model and approximate it by a cluster of discrete data. That's what it is. The maths come first. Then you go to the lab. Or... the lab surprises you. Then you go to the math.

It's from the blackboard to the lab, and back. Simulations being an in-between when direct calculations in the theory become too difficult. Like QCD, or many-body problem in GR.

That's the way I understand it, anyway. And most people here seem to agree.

[Genady]

In fact, simulations are MORE math. Given equations that cannot be solved exactly, developing a working method for solving them numerically is a nontrivial math itself.

[swansont]

19 minutes ago, Genady said:

In fact, simulations are MORE math. Given equations that cannot be solved exactly, developing a working method for solving them numerically is a nontrivial math itself.

Agree - I was going to point out that a simulation is a numerical solution and/or iterative sequence. A lot of math, with the computer cranking through it.

[joigus]

On 11/15/2024 at 11:13 PM, Genady said:

In fact, simulations are MORE math. Given equations that cannot be solved exactly, developing a working method for solving them numerically is a nontrivial math itself.

Well, of course they are MORE math. But that math is highly subordinate to the actual theory from which they derive. You cannot think of a simulation ab initio, with no formalism to derive it from.

[Genady]

27 minutes ago, joigus said:

... that math is highly subordinate to the actual theory from which they derive...

I disagree. Computational methods are math by itself which are applied to math of the physical theories. E.g., FEM.