This passage is adapted from Natalie Wolchover’s “What Is the Higgs Boson?” originally published in Quanta Magazine, an editorially independent online publication supported by the Simons Foundation. In 1964, the British physicist Peter Higgs wrote a landmark paper hypothesizing why elementary particles have mass. He predicted the existence of a three-dimensional “field” that permeates space and drags on everything that trudges through it. Some particles have more trouble traversing the field than others, and this corresponds to them being heavier. If the field—later dubbed the Higgs field—really exists, then Higgs said it must have a particle associated with it: the Higgs boson.
Fast forward 48 years: on Wednesday (July 4), physicists at the Large Hadron Collider (LHC), the world’s largest atom smasher in Geneva, Switzerland, announced they had discovered a Higgs-like particle at long last. If the new particle turns out to be the Higgs, it will confirm nearly five decades of particle physics theory, which incorporated the Higgs boson into the family of known particles and equations that describe them, known as the Standard Model.
The search for the Higgs gained a level of public attention unusual for physics, partly thanks to the physicist Leon Lederman’s 1993 book The God Particle. Lederman gave the Higgs its godly nickname because, as he wrote in the book, the particle is “so central to the state of physics today, so crucial to our final understanding of the structure of matter, yet so elusive.”
Indeed, the Higgs boson eluded detection through the construction and shutdown of two expensive high-energy particle colliders built partially for the purpose of detecting it. In these colliders, particles are accelerated through a tunnel and then smashed together, producing an excess of energy that sometimes takes the form of new and exotic particles. Only the Large Hadron Collider at CERN Laboratory, the most powerful particle collider ever built, turned out to probe energies high enough to generate a Higgs particle, which is roughly 125 times the mass of a proton.
But what does the Higgs particle actually do? How does it, and the Higgs field associated with it, give things mass? In physics, when particles interact with fields, the interaction must be mediated by a particle. Interactions with the electromagnetic (EM) field, for example, are mediated by photons, or particles of light. When a negatively charged electron is pulled by the EM field toward a positively charged proton, the electron experiences the EM field by absorbing and emitting a constant stream of “virtual photons”—photons that momentarily pop in and out of existence just for the purpose of mediating the particle-field interaction. Furthermore, when the EM field is “excited,” meaning its energy is flared up in a certain spot, that flare-up is, itself, a photon—a real one in that case.
Along the same lines, the Higgs particle mediates interactions with the Higgs field, and is itself an excitation of the Higgs field. Particles are thought to trudge through the Higgs field (thereby acquiring mass) by exchanging virtual Higgs particles with it. And, the thinking goes, a real Higgs particle surfaces when the field becomes excited, flaring up with energy in a certain spot. Detecting such a flare-up (i.e. the particle) is how physicists can be sure the field itself exists. At the LHC, they managed to bash atoms together hard enough to generate, for a fleeting instant, a 125 giga-electron-volt excitation of what was likely the Higgs field. The flare-up had all the trappings of a Higgs boson.
Licensed under CC BY-ND, https://creativecommons.org/licenses/by/4.0/legalcode. This passage has been excerpted and adapted from the original, including minor punctuation changes, spelling changes, and other modifications that have not substantially changed content or intent.
The Higgs Mechanism
The figure above shows the Higgs mechanism.
Source: https://www.dreamstime.org The passage implies that the scientists were able to obtain evidence of the Higgs boson by Not Answered A) utilizing a more powerful microscope than ever before. B) measuring trace elements of photons and electrons in the Large Hadron Collider. C) first trying to manufacture conditions that would lead to a Higgs field. D) using theoretical models to prove the probable existence of the particle. Which lines in the passage best support the answer to the previous question? Not Answered A) Paragraph 3, Sentence 1 (“The search . . . Particle”) B) Paragraph 4, Sentence 1 (“Indeed . . . it”) C) Paragraph 6, Sentence 3 (“And . . . spot”) D) Paragraph 6, Sentence 5 (“At the . . . field”) Which of the following is one of the main troubles the author discusses about research on the Higgs boson? Not Answered A) Most researchers dismiss theories about the Higgs boson. B) The Higgs boson is extremely difficult to detect. C) Public funding for physics research has substantially declined. D) International cooperation on scientific research is low. The passage begins with a discussion of British physicist Peter Higgs in order to Not Answered A) provide an anecdote about the power of science before discussing the more specific topic at hand. B) introduce the researcher who finally helped researchers demonstrate the existence of the Higgs boson. C) state a thesis about Peter Higgs’s life, which the author will spend the rest of the passage defending. D) illustrate the history behind the development of theories about the mystery particle. The passage indicates that, compared to other particle accelerators, the Large Hadron Collider was Not Answered A) more powerful. B) less expensive. C) more famous. D) less accurate. The passage suggests that the public viewed the Higgs boson with Not Answered A) bland indifference, due to the long process of discovery. B) strong skepticism, given the lack of scientific research to support it. C) unusual attention, due to popular writing on the subject. D) great fear, given the dangers of using the Large Hadron Collider. In Paragraph 2, Sentence 1, the phrase “at long last” is used to indicate that Not Answered A) researchers had finally made a key discovery about the particle. B) scientists had amassed a large amount of data about the particle. C) the Higgs boson was much larger than previously anticipated. D) the discovery of the Higgs boson was a permanent achievement. The graphic associated with the passage indicates that Not Answered A) Higgs bosons have no mass and low energy. B) quarks have high mass and high energy. C) electrons have high mass and low energy. D) photons have no mass and high energy. CERN Laboratory : Geneva, Switzerland :: Not Answered A) Higgs field : Large Hadron Collider B) Higgs field : photon C) Large Hadron Collider : CERN Laboratory D) Leon Lederman : The God Particle Higgs field becomes excited : real Higgs particle surfaces :: Not Answered A) The God Particle book is published : Higgs search gains public attention B) Higgs field : Large Hadron Collider C) Leon Lederman : The God Particle book is published D) Large Hadron Collider : particle collider
Here are the answers to your questions based on the passage provided:
The passage implies that the scientists were able to obtain evidence of the Higgs boson by: D) using theoretical models to prove the probable existence of the particle.
Which lines in the passage best support the answer to the previous question? D) Paragraph 6, Sentence 5 (“At the . . . field”)
Which of the following is one of the main troubles the author discusses about research on the Higgs boson? B) The Higgs boson is extremely difficult to detect.
The passage begins with a discussion of British physicist Peter Higgs in order to: D) illustrate the history behind the development of theories about the mystery particle.
The passage indicates that, compared to other particle accelerators, the Large Hadron Collider was: A) more powerful.
The passage suggests that the public viewed the Higgs boson with: C) unusual attention, due to popular writing on the subject.
In Paragraph 2, Sentence 1, the phrase “at long last” is used to indicate that: A) researchers had finally made a key discovery about the particle.
The graphic associated with the passage indicates that: D) photons have no mass and high energy.
CERN Laboratory : Geneva, Switzerland :: C) Large Hadron Collider : CERN Laboratory
Higgs field becomes excited : real Higgs particle surfaces :: A) The God Particle book is published : Higgs search gains public attention
Feel free to ask if you have any more questions or need further clarification!