The amazing discoveries of Tevatron collider

A month ago Adrian Cho wrote in Science Magazine about the shutdown of the United States’s great atom smasher, the Tevatron collider at Fermi National Accelerator Laboratory (Fermilab).

Cho stated that during its 25 years of operation, the Tevatron “yielded no surprises to make physicists rethink their standard model of fundamental particles and forces.”

This statement completely ignores at least two amazing discoveries by Tevatron – the discovery that contradicted asymptotic freedom and the discovery that proved beyond any reasonable doubt the existence of massive particles inside the proton. Both discoveries are in total disagreement with the standard model. Cho continues a tradition of ignoring experimental results that are not inline with the ruling theory.

The P-P cross section graph
The cross section graph is measured in experiments where two particles collide. This graph provides useful information about the forces between two interacting particles and about the distance dependence of these forces.

According to quantum mechanics a particle behaves as a wave whose properties depend on the particle’s velocity. The wavelength of a particle is shorter when the particle moves faster. Therefore, when two particles collide, the effective distance between them at the collision time cannot be much smaller than their wavelength.


The effective distance between two particles at the time of their collision depends on their wavelengths. Their wavelengths depend on their velocity.

What happens when two particles hit one another? This question is not as trivial as it sounds. When particles do not apply forces on each other, they may go through one another without any interaction. Neutrinos, for example, pass through the entire earth easily. A collision appears when the particles interact and momentum is exchanged.

We can learn about the electromagnetic forces by examining the formula describing the measured cross section of electron-proton collisions. When an electron hits a proton, their interaction stems only from their electric charges. The cross section curve decreases when the energy of the electron increases. Here the slope of the cross section curve is related to the potential of the electromagnetic field.

According to the electromagnetic equations, the potential is proportional to 1/r where r denotes the distance from the charged particle to the point where the potential is measured. Calculations show that for high energies, this potential formula yields a cross section graph of the electromagnetic interaction that decreases like 1/p2, where p denotes the particle’s momentum.[1]

It is convenient to use logarithmic scales in cross section graphs where the 1/p2 relation appears as a straight line.

Now, after having some ideas about cross section curves, let’s examine the proton-proton cross section graph.[2]


Proton-proton cross section curve, divided to five zones.

Here I added red vertical lines in order to divide the graph into five zones. The zones’ order indicates an increase of the collision energy and consequently the decrease of the corresponding proton’s wavelength.

In the leftmost zone, zone 1, the proton’s energy is rather low and its wavelength is quite long. Here the effective distance between the particles during their collision is so long, that the actual force involved is the electromagnetic force associated with the protons’ overall electric charge. In this zone the graph behaves as expected: it decreases in a straight line, proportional to 1/p2.

In zone 2, the graph stops decreasing. In this zone the proton’s momentum is larger than in zone 1 and the corresponding wavelength is shorter. In this zone, the effective collision distance is quite short and the protons apply strong nuclear force on one another. This force varies rapidly and the 1/r of the potential formula does not hold any more. This is the reason for the rapid change in the slope of the cross section graph.

In zone 3, the graph splits into two parts: the elastic cross section (the lower graph) and the total cross section (the upper graph). The two graphs satisfy the rules that mentioned earlier.

In zone 3, the wavelength is shorter and the protons are so close during their collision that in some cases individual quarks of one proton interact with quarks of the other. This means that the strong force becomes significant. This force is much stronger than the strong nuclear force and it explains the rapid increase of the total cross section graph.

Up to here everything is agreed by all particle physicists. Zone 4 and zone 5 were measured in Tevatron, and they provide two amazing discoveries.

The P-P cross section graph vs. asymptotic freedom
Zone 4 represents higher energy collisions and shorter proton’s wavelength. Here individual quarks of one proton collide with quarks of the other.

The behavior of the graph at zone 4 shows beyond any doubt that there is no asymptotic freedom.

How do we expect the graph in zone 4 to behave if asymptotic freedom holds?

If the strong force would behave similarly to the electromagnetic force, meaning that the force increases while the distance decreases, and the increasing potential is proportional to 1/r, then the graph would drop similarly to its behavior at zone 1. However, if one adopts asymptotic freedom, then the force decreases while the distance decreases. This implies an even more dramatic declining slope of the cross section graph.

However, contrary to the asymptotic freedom expectation, the graph’s decreasing slope is even less steep than that of zone 1!!

The outcome of this discussion is that the force between the quarks of one proton and the quarks of the other increases while the distance decreases, contrary to QCD’s asymptotic freedom expectation.

Late 1990s, DESY laboratories, Germany
The results of experiments conducted at the DESY Labs in Germany were published in 1997. These experiments consisted of bombarding protons with beams of electrons or positrons, at higher energy than ever before. The experiment was performed from 1994 to 1996 by two independent groups of researchers, at two different locations of the device. The results obtained from both experiments were similar, and surprising.

Physicists expected to see a decrease in the cross-section curve for higher energies, because of a fundamental rule established about a century ago, stating that the probability of a collision between an electron (or a similar particle) and a proton decreases as the incident particle’s energy increases.

However, the results here showed an unexpected relative increase in the number of collisions as energy increased. The discovery was followed by the publication of two papers expressing astonishment with regard to these findings.[3][4]

Frank Sciulli, professor of physics at Columbia, who drafted one of the papers reporting the observations, said: “If the results are not a statistical fluke, new physics has been observed. One possibility is that our understanding of what’s inside the proton is somehow wrong.”[5]

What are the possible explanations for this increase in interactions when the beam’s energy goes up?

The plausible explanation is that there are other entities inside the proton capable of absorbing this energy only above a certain threshold. This explanation obviously contradicts QCD.

The groups conducting the experiments concluded, quite reasonably, that their findings might be accidental, because not enough data were collected to be clearly statistically significant.

Early 2000s, Fermilab, Illinois
In an experiment, conducted some 10 years ago in the Tevatron Collider at Fermilab in Illinois, USA, a proton beam collided with another proton (or anti-proton) beam, at energy levels even higher than those reached at DESY, with clear cut results. The proton-proton cross-section curve does indeed stop decreasing and begins to move up when the beam’s energy goes beyond a certain threshold. See zone 5 in the figure above.

Furthermore, the rate of elastic collisions increased as well. In other words, a change of tendency was observed both in the total and the elastic cross sections, and their curves changed directions and started to increase.

This finding has been known for several years now and is supported by earlier results. The only plausible explanation for this is the existence of massive particles inside the proton, which get “excited” at this high energy level and produce this tendency change in the curve. These massive particles can only occupy specific energy levels, and react to the collision only when the energy of the incident particle is high enough to excite them and move them to a higher energy level.

An essential element of QCD states that protons (and all other baryons) consist of the three valence quarks, additional quark-antiquark pairs and gluons. In this theory there is no room for another proton component that enters the interaction only when collision energy is higher than a certain threshold.

Therefore, there is no explanation for this fundamental effect within the framework of QCD.

Doubts are not allowed
Adrian Cho, the journalist who wrote that “Tevatron yielded no surprises” is not alone. Journalists, scientists and the whole public are experiencing a tremendous brainwashing which eliminates any possibility to make any doubt regarding any part of the standard model.

In this web site you could find nearly 20 phenomena which are not explained by the standard model, some of them, like the two above, seem to be blatant contradictions to QCD. These experimental data were published in mainstream physics journal.

Several parts of the standard model were successful. But QCD, although being part of the standard model, doesn’t seem to provide reasonable answers to many questions in the field of strong interactions.

Why then so many journals do not publish any scientific paper challenging QCD?

[1] D. H. Perkins, Introduction to High Energy Physics, (Addison-Wesley, Menlo Park CA, 1987). p. 186-189.
[2] C. Amsler et al. (Particle Data Group) Physics Letters B667, 1 (2008) see p.12 here
[3] C. Adloff et al., Observation of Events at Very High Q2 in ep Collisions at. HERA, Z. Phys C74, 191 (1997)
[4] J. Breitweg et al., Comparison of ZEUS Data with Standard Model Predictions for ep -> eX Scattering at High x and Q2, Z. Phys C74, 207 (1997)
[5] Columbia University News, 1997.

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