As scientists developed the Standard Model of physics (the generally a

As scientists developed the Standard Model of physics (the generally accepted framework that explains how subatomic particles interact) in the 1960s and 1970s, they began to ask: How do subatomic particles acquire mass? The Standard Model gave satisfactory results in other areas in which it had been tested, but the mathematics behind the model seemed to prohibit subatomic particles from having any mass at all, which meant that the model was incomplete. Scientists speculated that a mechanism must exist that causes such particles to gain mass, but does not violate the principles of the Standard Model. They theorized that a field known as the Higgs field would allow such a mechanism to function, and that the Higgs field would have an accompanying Higgs boson particle.

In attempting to find this missing mechanism, physicists have focused on the Higgs boson. If experiments prove that the Higgs boson exists, then scientists can be satisfied that this part of the Standard Model is accurate. On the other hand, if results demonstrate that the Higgs boson does not exist, then scientists will need to consider alternative versions of the theory. Finding the Higgs boson, however, has proven challenging. If it were similar to lighter, more commonly found bosons, such as photons, it would be easily identifiable. However, this particle can only be created through highly energetic particle collisions achieved by massive particle accelerators, and even then, such particle collisions are just as likely to produce particles other than the Higgs boson. Further complicating matters, any Higgs bosons that are created will only exist for mere fractions of a second before quickly decaying, which means that rather than studying the particles directly, scientists must analyze the patterns of the decay in order to determine whether the particle was in fact a Higgs boson.

Recent findings have nevertheless been promising. In July 2012, scientists at the European Organization for Nuclear Research announced that they had discovered evidence of a boson with energy and other properties consistent with those predicted for the Higgs boson. While the data is not yet conclusive, if the particle can indeed be shown to be a Higgs boson, then scientists will be able to take the next step of considering whether its characteristics match those predicted by the Standard Model.

1. Based on the information presented by the author, it can be inferred that if Higgs bosons did not exist

A) the current theory of how particles gain mass would have to be adapted
B) subatomic particles would not be able to gain mass
C) the Standard Model would be proved erroneous
D) scientists would be forced to look for another, lighter particle
E) more experiments using highly energetic particle collisions would have to be conducted

2) The primary purpose of the passage is to

A) present a disputed theory and defend its accuracy
B) criticize a conventional model and argue for an alternative theory
C) outline an issue and demonstrate the unlikelihood of resolving it
D) describe a problem and examine its possible solutions
E) contrast two different models and show that one is more accurate

3) The author’s claim that “if experiments prove that the Higgs boson exists, then scientists can be satisfied that this part of the Standard Model is accurate” would be most undermined by the discovery that

A) many subatomic particles produce decay signatures that are similar to those predicted for the Higgs boson
B) in order to create mass, the Higgs field must work with another unidentified mechanism that requires its own accompanying particle
C) Higgs bosons and photons are both highly energetic and can decay very rapidly when created by particle accelerators
D) the particle discovered at the European Center for Nuclear Research has some properties that are not consistent with those predicted for the Higgs boson
E) most collisions created by particle accelerators produce particles other than Higgs bosons, so the probability of discovering the Higgs boson is very low

4. According to the passage, if Higgs bosons exist, then they possess all of the following properties EXCEPT

A) a fast decay rate
B) the ability to work in conjunction with the Higgs field
C) a difficulty to be detected if they were created
D) be created by massive particle detectors
E) relatively little mass