San José State University

applet-magic.com
Thayer Watkins
Silicon Valley,
Tornado Alley
& the Gateway
to the Rockies
USA

What an Incredibly Weak Criterion
of Physical Truth is the Ability
of a Set of Assumptions to
Explain a Physical Fact

More than incredibly weak the notion that the ability to explain phenomena implies truth is just not valid.

Suppose there is a known physical fact B. Suppose further that a set of assumptions A={a1, a2, ...., an} implies that B should be true. The fact that B is true and the set of assumptions A implies it should be true does not mean that all of the assumptions in A are true. Those conditions only imply that the set of assumptions, one by one, might be true. There could be another set of assumptions, say C, that also imply B. That means that the set C might be true. It is possible that sets A and C contradict each other in other matters. There is no logical difficulty in there being two sets of assumptions that might be true even if the two sets are not compatible.

But this is not how the ability of one set of assumptions to explain a physical fact B has often been treated in many scientific endeavors. All too often the ability of a set of assumptions A to explain physical fact B is taken to mean that a1 is true, a2 is true and so on up to an being true.

When researchers are searching for a set of assumptions that will explain a physical fact they are not limited to the known Universe. They may hypothesize things that are not known to exist. Such hypotheticals could have characteristics which are unlike any known things in the Universe. That would be alright if they only concluded that these might exist. But that not the it is often done.

An Example

Here is an example from nuclear physics. Ernest Rutherford demonstrated that an atom contains a core of positive charges. It was well known that like charges repel each other. So there was a perplexing puzzle of how multiple positive charges could be stably held together in an atomic nucleus. When the neutron was discovered in 1930 physicists said in effect, "Suppose neutrons and protons are attracted to each other with a force which drops off faster with separation distance than does the electrostatic repulsion between protons. Thus at small separation distances the protons are held together but at larger distances they are repelled from each other." These assumptions did explain how multiple positively charged might be stably held together in a nucleus. But the theorists in 1930 did not characterize it in terms of might. They stated it as established fact. The hypothetical force between nucleons was given a name, the nuclear strong force and its existence proclaimed as fact. The existence of stable nuclei containing multiple positive charges was taken as evidence for the existence of the nuclear strong force.

Here is the top response in a Google search to the question of what holds the nucleus of an atom together.

The strong nuclear force. At extremely short range, it is stronger than electrostatic repulsion, and allows protons to stick together in a nucleus even though their charges repel each other.

There is no hint of uncertainty nor that the only established fact is that there are stable nuclei containing multiple positive charges. For an alternate explanation of stable nuclear structure see Nucleus That alternative theory equally well explains how multiple positive charges can be held together so it should be considered as true as the conventional nuclear strong force theory.

An Even More Egregious Example

Background

In the devices known as Cloud Chambers there are patterns of lines that can be explained as being the result of collisions of particles. The existence of some patterns can be explained as being the result of the existence of certain particles. Thus the only evidence for the existence of some particles is that their existence explains certain observable patterns of tracks in a cloud chamber.

In 1964 Murray Gell-Mann of Cal Tech published a proposal that protons, neutrons and other hadrons were composed of even more fundamental particles. George Zweig independently made a similar proposal. Gell-Mann chose call those fundamental particles by a name pronounced as kworks but later found in Finnegan's Wake the word quarks and chose to use that for the spelling of the name he had chosen. Zweig had chosen to call his fundamental particles aces. Quarks won out in the physics community.

Gell-Mann's quarks came at that time in three different varieties which he called Up quarks, Down quarks and Strangeness quarks. Later three additional varieties were proposed to explain the existence of several varieties of exotic particles; the Charm quarks, the Top quarks and the Bottom quarks.

Gell-Mann's theory of quarks was an outgrowth of a formulation he proposed in 1961 which he called The Eightfold Way.

Technicalities

It was proposed that an Up quark has a positive charge of 2/3 of an electrostatic unit. On the other hand a Down quark has a negative charge of 1/3 of an electrostatic unit. Therefore a proton had to have two Up quarks and one Down quark. A neutron had to have two Down quarks and one Up quark.

Later it was found that quarks needed to have one of three different attributes. These were called color although they have nothing to do with visual color. Furthermore in order to explain some phenomena each hadron had to have quarks of each of the three attributes (colors).

Existence of Quarks

When particle physicists looked for patterns of cloud chamber tracks that could be attributed to singleton quarks they did not find them. One obvious explanation for not finding them is that quarks do not exist. This explanation was not given much consideration. Instead they searched for any explanation no matter how wild and implausible that would account for the nonexistence of cloud tracks for singleton quarks.

The one they came up with involved the force of attraction between two quarks increasing with separation distance. There is no known field force with that characteristic. This is called the Bag Model of quark confinement.

At the other extreme, when the separation distance between quarks goes to zero the attraction force between two quarks goes to zero. This is called asymptotic freedom.

Furthermore in the conventional theory quarks are considered to be point particles. However there is not enough energy in the entire Universe to create one charged point particle even if all the mass in it were converted to energy. And in the Universe there is not just one quark but zillions upon zillions of them. This illustrate that the set assumptions for explaining a physical fact is not limited to known facts about the physical world.

Thus although the conventional theory of the quarkic structure of hadrons does explain the nonobservation of singleton quarks that only implies at most that it might be true. It is not only set of assumptions that explains that single fact of the nonobservation of singleton quarks. For an example of an alternate explanation of that single fact see Quark Confinement. S

The Nonconfirmation
of an Implication

Sometimes there is a set of assumptions A={a1, a2, ...., an} which implies that B should be true, but B is found not to be true. That logically implies that not all of the assumptions of A are true. It has occurred, in the case of the Bell Theorem, that its nonconfirmation implies unjustifiably that a particular assumption is not true. John Stuart Bell derived an inequality that should be satisfied by material particles impinging upon a measuring device. The results were supposed to depend upon the angle of impingement. When that inequality was not satisfied it was concluded that the particles did not have a continuous material existence. Bell's derivation also assumed among other things that charged particles in a beam travel in strictly straight lines. Charged particles traveling in a beam develop tansverse oscillations in their paths because of their repulsion from each other. Such transverse oscillations would drastically affect the angle of impingement of the particle with the measuring device. Thus it could be that it is this assumption which is violated and explains the results of the experiment rather than the assumption of the materiality of particles.

The Tangled Logic
of Particle Entanglement

Sometimes pairs of particles are created with corresponding characteristics. They maintain those corresponding characteristics when separated. When the characteristic of one particle of a pair is observed the corresponding characteristic of the other particle is observed. This is all simple and obvious.

But the Copenhagen Interpretation of quantum phenomena maintains that particles do not have a physical existence until they are observed. Therefore they do have the corresponding characteristic until they are observed. Yet when one particle of a pair is observed and its characteristic determined the other particle of the pair is found to have the corresponding characteristic. This led to the notion that a pair of particles had a linkage even before they had a physical existence such that when the characteristic of one particle was determined the characteristic of the other was predetermined. This supposed linkage was called entanglement. Somehow entanglement involved some communication between the members of a pair.

Then experiments were carried out that involved the observation of the characteristics of a widely separated pair at times very close together. This raises the possibility that the results of such experiments could imply communication between the members of a pair at speeds faster than that of light, contrary to the Special Theory of Relativity. Rather than abandoning the notion of entanglement the followers of Copenhagen Interpretation continued accept it on the basis that it provided an explanation for the results of a set of experiments that had a simpler obvious explanation.

Computability

If a theory results in the computation of some numerical results which might be found or not found to be true that is a quite notable aspect of the theory. There are some theories, such as String Theory, for which that is not true. But until those computed results are confirmed they are of no significance. Even if they are confirmed it only means that the theory might be true because the same results might be derived from an alternate theory or theories.

But if there is no way to confirm the results then their computation means absolutely nothing. Instead how unexpected or absurd are the results is taken to indicate how impotant they are, even though they are unconfirmed, Examples of these are recent studies purporting to derive the source of proton spin from its composition in terms of quarks, antiquarks and gluons. Protons conventionally are thought to be composed of two Up quarks and one Down quarks. In such studies a proton is taken to include a frothing sea of quarks, antiquarks and gluons.

Conclusions

The fact that a set of assumptions explain a physical fact does not establish the truth of that set of assumptions; it only at most establishes that those assumptions might be true. If those assumption imply other things that are not true then the set of assumptions are not all true. There are significant cases in hard science in which the truth of a theory has been proclaimed simply because it explains why some observed facts might be true. This is not valid. If it did involve a valid principle the truth of contradicta\tory theories would have to be proclaimed simply because they explained the same phenomena.

This invalid principle has allowed elements of shear fantasy such as to the existence of entirely hypothetical particles and forces to become accepted as verified reality.


HOME PAGE OF applet-magic
HOME PAGE OF Thayer Watkins