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ACT Question for September 21st


               It may seem surprising that many scientific
          theories that are awarded the Nobel Prize were
          once met with disbelief by the scientific
          community. But Hannes Alfven knew all too well
(5)      that it can take decades before a theory even
          begins to be accepted.
               Alfven was a University of California physicist
          whose work in the 1930s with cosmic radiation
          led him to propose the existence of a galactic
(10)   magnetic field. Even though Alfven had
          established a solid reputation through his
          discovery of certain principles of cosmic
          radiation, his colleagues universally condemned
          his new idea as preposterous, as the workings of
(15)   a young upstart who was reaching too far.
               Undeterred by his critics, Alfven went on to
          prove the existence of the ring current, a
          fundamental component of the Earth’s
          magnetosphere. His work on the magnetosphere
(20)   was irrefutable and did establish that certainly
          there was some force in distant space that
          seemed close to what he had initially posited
          with his concept of a galactic magnetic field.
          Instead of furthering his work in this direction,
(25)   in an attempt to prove that he had been correct
          all along, Alfven seemed content that at least
          some of his theories were being accepted. “My
          team were thankful,” he said later, “that we
          weren’t met with the same level of controversy
(30)   once again.”
               This type of “infighting” among scientists
          may seem strange to the casual observer. Aren’t
          scientists supposed to be objective and open to
          new ideas and new explanations? Even if a new
(35)   theory forces revision or reconsideration of an
          older theory, isn’t such re-evaluation at the core
          of the scientific method? Ideally, this is true, but
          in actuality, scientists can be as stubborn about
          change as everyone else.
(40)        “A scientist suffers from a split personality,”
          asserts Austin Rogers, co-president of the
          American Institute of Physics. “A scientist trusts
          that his theory is true, but at the same time has
          to systematically cast doubt on it. Someone who
(45)   questions his theory too much will never make
          progress, yet if he is convinced of the certainty
          of it, he may end up looking foolish.”
               Alfven was skilled at straddling these
          conflicting points of view. He was proficient at
(50)   experimentation and developing laboratory
          proofs, but even more adept at approaching
          problems with keen insight and making
          great intuitive leaps. This ability is what
          initially led Alfven to construct a model of a
(55)   galactic magnetic field. He and his colleagues
          were conducting observations of sunspots and
          calculating sunspot cycles when an anomaly
          began to appear in the data. The other scientists
          were convinced that it was only a “trick” of the
(60)   mathematics, caused by variations in the solar
          winds, but Alfven leapt to the conclusion that it
          was evidence of an entirely different force.
               Alfven’s vague notion soon became a concept
          that he worked on rigorously, to the point at
(65)   which he was ignoring the rest of his work.
          Eventually, it became the theory that he
          presented to his peers in 1938, a theory that
          was quickly rebuked, not because it was
          mathematically unsound but simply because it
(70)   seemed too unusual.
               The anomaly had showed the sun cycle data
          to be off by a mere hundred thousandth
          (.00001), well within the range of a statistical
          fluctuation and easy to dismiss. The
(75)   phenomenon that Alfven proposed would have
          been operating from several light years away,
          and even to have caused this minor
          perturbation, would have to have been an
          exceedingly powerful force. Imagine a bowling
(80)   ball that is spinning on its axis and is three
          thousand miles away from you. To cause from
          such a distance a slight disruption in its spin
          would require a force equivalent to five
          thousand atomic bombs!
(85)        It’s somewhat understandable then why
          Alfven’s theory was met with such widespread
          skepticism. Nonetheless, Alfven later continued
          to formulate the concept of a galactic magnetic
          field, even going so far as to proudly name the
(90)   force generated by the field Alfven waves. It was
          not until, at a seminar ten years later, a
          more prestigious physicist, Enrico Fermi, said “of
          course such waves could exist” that Alfven’s
          theory began to be looked at more closely.
(95)   Further experiments confirmed that the anomaly
          Alfven had detected was not just a random
          fluctuation but was evidence of some external
               Today, Alfven’s theory and the existence of
(100) Alfven waves are still unproven; however, the
          galactic magnetic field is considered a valid field
          of research, and in 1970 Alfven received the
          Nobel Prize for his work in cosmic
          electromagnetic fields. One has to wonder: if
(105) Alfven had not received support from the
          eminent physicist Enrico Fermi, would the theory
          of a galactic magnetic field ever have been

When Austin Rogers says that scientists "suffer from a split personality" (line 40), he most nearly means that they:

Yes, a scientist's work might be conflicting, but to say that it causes him mental problems is taking this quote too literally.

Both this choice and (C) sound good since they reflect ideas and phrases that are contained in the 5th paragraph. However, both of these choices put forward an "either / or" situation, where the scientist has to choose one extreme or the other. In fact, the scientist has to maintain both views, balancing the extremes.

Both this choice and (B) sound good since they reflect ideas and phrases that are contained in the 5th paragraph. However, both of these choices put forward an "either / or" situation, where the scientist has to choose one extreme or the other. In fact, the scientist has to maintain both views, balancing the extremes.

This answer shows that scientists have to be critical of their theories and the results of their experiments but also have to accept them.

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Question ID: 1105