Why Trust a Theory?

[shirgall]

A bunch of string theorists got the bright idea of trying to change the scientific method in order to garner more trust for their idea.

 

Speculative science shouldn't have to meet the same levels of testability and falsifiability!

 

Other scientists pushed back: http://www.nature.com/news/scientific-method-defend-the-integrity-of-physics-1.16535

 

Comedy ensued.

 

 

This battle for the heart and soul of physics is opening up at a time when scientific results — in topics from climate change to the theory of evolution — are being questioned by some politicians and religious fundamentalists. Potential damage to public confidence in science and to the nature of fundamental physics needs to be contained by deeper dialogue between scientists and philosophers.

 

My favorite coverage of the event is this Philosopher's notes on the meeting:

 

https://platofootnote.wordpress.com/2015/12/08/why-trust-a-theory-part-i/

https://platofootnote.wordpress.com/2015/12/09/why-trust-a-theory-part-ii/

https://platofootnote.wordpress.com/2015/12/10/why-trust-a-theory-part-iii/

 

Some tidbits:

 

 

Contra popular misunderstanding among the American public (as in “it’s just a theory”), theory of course plays a number of crucial roles in the workings of science. It aids in quantifying and modeling observations, suggesting new experiments and observations, predicting new phenomena, modeling and calculating the expected background to new experiments, and finally unifying disparate phenomena.

 

 

String theory itself set out validation criteria early on in its history: computing the parameters of the Standard Model from first principles, for instance, or deriving the existence of three families (of particles) from first principles, or predicting the sign of the cosmological constant, or predicting new particles to be discovered at LHC energy levels, or low energy supersymmetry, and so forth. According to Rovelli, all of these failed, turning string theorists into the mythical fox who argued she didn’t really like the grapes, once it was clear that she couldn’t reach them… [Nice classical reference to Aesop!]

 

 

Philosophical considerations cannot settle things in terms of string theory as a scientific theory, but part of the discussion has to do with the way science works, which is very much a philosophical issue.

 

The canonical view of science is that scientific theories must make testable predictions, which can be the only ones capable of confirming (or not) the theory. Without empirical confirmation, the theory remains speculative.

 

One reason for the canonical view was the desire for a simple demarcation criterion separating science from non-science [i’m not sure I buy this: one can empirically disconfirm astrology, for instance]. But if we think of experimental confirmation as increasing the probability of a theory’s viability, then we can adopt a broader Bayesian model of confirmation. We can then distinguish between standard empirical confirmation as we know it, by data predicted by the theory, and non-empirical confirmation based on observations of a kind the theory could not be expected to predict, because they are not in the theory’s original domain.

 

The full three postings is a lot of reading, but I find it to be interesting stuff.

[Normal Person]

A scientific theory is the product of the scientific method and therefore has been experimentally tested and confirmed many times.

 

The string theory is not a scientific theory. Theoretical physics is not scientific. 'Speculative science' is a contradiction in itself.

 

I am not surprised that some string theorists demand theoretical physics to be excluded from scientific standards and be accepted apparently just for their 'elegance'. To my knowledge string theorists have not produced any result. It is in their interest to counteract the consequently waning popularity and funds by enforcing acceptance.

 

Yet this desperate and selfish attack on science is despicable. Omitting elements of the scientific method destroys science's credibility.

[polyb1123]

I'm reminded of my experience as an undergraduate student working in the lab on a directed independent research project. One day while a graduate student of my professor was in there with me, we were both looking at a screen that displayed the spectral profile that was hooked up to a detector. Generally what one observed was a scragglly line across the bottom of a graph corresponding to the spectrum being observed. Of course, quite randomly, a spike would pop up and disappear. This lead is into the speculation of what that really was and how the explanation was cosmic particles hitting the detector at random intravels. What really caught my attention was the statement the graduate student made: "... so goes the theory!" I personally relished his statement because it helped me in understanding with all the theoretical descriptions that does go on in physics we are really left with just that: a description. This is vastly different from understanding! But that is how it really is in physics, more often than not to my disappointment.

 

Unfortunately the clarion call of scientific authoritarianism clouds the very simple fact that science is far from complete as a framework for understanding the nature of reality. Worse, it also, imho, is a very dishonest practise because instead of enlitghening people to how reality really works it buries the uninitiated in a fog of incomprehensible description. As far as I am concerned this a great disservice and only serves to secure a position of power for those would be priests of science. The ole knowledge differential used to exploit the less knowledgable. Not to mention this discredits science as a whole, imho. I think it is valid to conclude that there are a lot of irrational scientists out there who promote such irationality because it serves their interest. It has been difficult for me to come to such a conclusion but I can't say there really is much other choice. I do certainly promote crtical thought of science because this is in essence what science is really about! But then again this is more philosophy than science, indeed!

 

Hail Kallista!(LOL!)

[A4E]

Another problem is theories which sole purpose is to defend other theories when they fail.

 

The theory of gravity in its current established form does not explain how a galaxy rotates, or even how a galaxy is held together, because of the speeds on the outer arms. So instead of putting the old theory on the shelf, the dark matter theory was created to defend it. Now all the additional dark matter will keep the galaxies together.

 

But this created another problem, because observations apparently told us that the universe is expanding. How can that be if there is so much pull on everything from dark matter?  Dark energy comes to the rescue!  Now both dark matter and dark energy tries to explain everything on top of the theory of gravity. We have no real evidence of either of these, they are literally just made up assumptions based on the theory of gravity.

 

I suspect it has something to do with everyone wanting to clam onto the established theory of gravity, because admitting that it may be false is too much to bare. The following quote from a site is a good example of this:

 

"Let me begin by telling you that dark matter is real. The evidence is overwhelming. Without dark matter stars would escape their galaxies and galaxy clusters would come unbound."

[shirgall]

We trust theories that are consistent with the evidence that abounds around us and that are also logically consistent. Gravity works with the things that can can observe directly.

 

Dark matter is called "dark" because we don't know enough about it to describe it. The theory of gravity describes the manner in which objects attract one another. It does describe how orbits work, even galactic ones, but in the galactic case there is evidence of mass that is not yet accounted for. Dark matter is simply a label for that missing mass and the investigation of dark matter is simply the search for that mass.

 

Don't complicate things. When you see the "dark" label, just remember that it just means that there's something that should be there based on the effects of it but they haven't found yet.

[Will Torbald]

Another problem is theories which sole purpose is to defend other theories when they fail.

 

The theory of gravity in its current established form does not explain how a galaxy rotates, or even how a galaxy is held together, because of the speeds on the outer arms. So instead of putting the old theory on the shelf, the dark matter theory was created to defend it. Now all the additional dark matter will keep the galaxies together.

 

But this created another problem, because observations apparently told us that the universe is expanding. How can that be if there is so much pull on everything from dark matter? Dark energy comes to the rescue! Now both dark matter and dark energy tries to explain everything on top of the theory of gravity. We have no real evidence of either of these, they are literally just made up assumptions based on the theory of gravity.

 

I suspect it has something to do with everyone wanting to clam onto the established theory of gravity, because admitting that it may be false is too much to bare. The following quote from a site is a good example of this:

 

"Let me begin by telling you that dark matter is real. The evidence is overwhelming. Without dark matter stars would escape their galaxies and galaxy clusters would come unbound."

This argument would have been interesting a few years ago, but the new evidence for dark matter really suggests it is much more than an ad-hoc made up thing. There have been observations where the mass of the galaxies does appear to be shifted outside of the visible matter in accordance to dark matter theories. Look for the bullet galaxy photographs for that.

 

Now it is true that there isn't one definitively confirmed theory of dark matter, but that it exists as a thing at all is almost undeniable by now. There are also people working on alternate or modified theories of general relativity without dark matter, but they do fail to explain the latest astronomic observations of galaxy clusters and the cosmic microwave background.

 

No one is yet claiming any absolute truth or authority over dark matter, but they are not taking out of their asses either. Dark energy isn't incompatible at all with dark matter since its effects are only noticeable on the largest cosmic scales in the space between galaxies, not within galaxies.

 

I suggest you update your information and watch some of the latest talks on the subject. I've been doing that, and there are plenty of lectures on why dark matter and energy are being taken very seriously now.

[A4E]

Lets say just for example that some person proves, explains, mathematically and physically show, and passes all tests and scientific methods, that everything is being pushed, not pulled.

 

Not saying this can be done. It is just an example. And I certainly don't know how the universe works.

 

Do you think you, or the world is ready to shelve the gravity pull theory and consider this new theory?

[shirgall]

Lets say just for example that some person proves, explains, mathematically and physically show, and passes all tests and scientific methods, that everything is being pushed, not pulled.

 

Not saying this can be done. It is just an example. And I certainly don't know how the universe works.

 

Do you think you, or the world is ready to shelve the gravity pull theory and consider this new theory?

 

If you have competing theories that explain all of the observations and accurately predict future ones, then the less complicated one wins.

[Will Torbald]

Lets say just for example that some person proves, explains, mathematically and physically show, and passes all tests and scientific methods, that everything is being pushed, not pulled.

 

Not saying this can be done. It is just an example. And I certainly don't know how the universe works.

 

Do you think you, or the world is ready to shelve the gravity pull theory and consider this new theory?

 

Gravity in GR pushes because space is curved into the center of mass of an object like a planet. Space pushes you into the planet or star. But dark energy is the same thing, but applied to space. According to GR, if space itself has energy inherent to it, the result is that space begins to expand and everything in it would be pushed away from each other. So the theory has always been about a push, not a pull. Pull is from Newton's gravity, but push is from Einstein.

[shirgall]

What is more frustrating is when you get edge cases that muddy the water.

 

For example, the High School Physics "F = ma" is wrong. It's actually "F = Δp / Δt". It's just that momentum is more difficult to teach than mass.

[Guest Gee]

What is more frustrating is when you get edge cases that muddy the water.

 

For example, the High School Physics "F = ma" is wrong. It's actually "F = Δp / Δt". It's just that momentum is more difficult to teach than mass.

 

+1. Physics is taught ass backwards.

[polyb1123]

What is more frustrating is when you get edge cases that muddy the water.

 

For example, the High School Physics "F = ma" is wrong. It's actually "F = Δp / Δt". It's just that momentum is more difficult to teach than mass.

I disagree! The principle of inertia is a concept we are all very familiar with. Objects generally do not move unless something comes along and moves it, ie an outside force. Loosely defined, inertia is an objects resistance to change, generally in terms of position. But the problem is that inertia is a concept, an idea. We can't really measure that and thus establish it objectively. But it is something we are all familiar with and can easily accept. So we have to be able to break it down to something we can actually measure if we are going to establish anything objective. From here we invoke momentum, equivelantly interia, as 'mass x velocity' where we can actually measure something. Though mass is trickier to measure and generally abstracted from other measurements, we can directly measure velocity: a change in position with respect to a change in time. This very important! We have something! Now we can go headlong into Newton's laws.

 

I would say that 'mass' is actually harder to define and understand because we cannot directly measure it but we can work around that through the familiar measure of weight. Also this is something we can ascribe to an object. That is a lot easier to contend with than the concept of inertia. But this is where it does become tricky because we are invoking measurements in order to establish objectively concepts like inertia, thus rendering it as a principle! This is the cornerstone of all physics.

 

Even though this tremendously helps us understand objectively the physical world around us it doesn't really help us understand why objects in general resist change! Imho, inertia is a huge mystery and this why the Higgs-boson is so sought after. For quite sometime no one has truly understood the cornerstone principle of inertia which directly ties into the idea of mass! Again, mass is not so simple!

 

One of the problems we do have is that ideas or theories can correspond with observations or measurements but that doesn't necessarily mean that we have the correct ideas. Worse a theory can loosely said to be a description but that does not necessarily help us really understand the phenomena we observe. Again mass has been very useful but the truth is that we really do not understand it. Hence, so goes the theory!

[Jsbrads]

I always enjoy this one by Richard Feynman:

The Essence of Science