News by Levels · Level 3 · For teachers

Teacher guide & answers

In this lesson: Apply the physical principle and distinguish publication timing from the experimental setup.

ORCA Constrains Possible Violations of Lorentz Symmetry

How to use these two pages

Give learners the student worksheet. It contains the story and questions, without the answers. Keep this guide for yourself. Use it to lead the activity and explain the answers afterwards.

Student worksheet

A simple 15–20-minute lesson

Before reading · 2 minutes
Show the title. Ask: “What do you think this story is about?”
Read and answer · 8–10 minutes
Give out the student worksheet. Learners read for the main idea, then reread to answer the 2 questions. They can compare answers with a partner.
Discuss and write · 5–8 minutes
Check the answers below together. Ask learners to point to the clue in the story, then finish with the open question.

Adjust the support: Let learners use word help or Level 1 if needed. For a challenge, compare the wording in another level. This activity is not a proficiency test.

Answers to the 2 questions

The question numbers match the student worksheet. Each answer includes a reason and the clue learners can find in the story.

Which conclusion follows from the analysis?
Correct answer: B — Selected effects now have upper limits, but not every violation is ruled out.
Why: The paragraph states a null result and limits on selected effects, explicitly rejecting an unrestricted proof of absence.
Clue in the story: An analysis of 1.4 years of data found no significant violation. It established upper limits on selected effects rather than proving that every possible violation is absent.
Two observers move at different constant velocities relative to each other. What does the principle require?
Correct answer: B — The physical laws must remain consistent for both observers.
Why: The principle concerns the consistency of physical laws for such observers. It does not require every measured energy or direction to be identical.
Clue in the story: The KM3NeT collaboration tested Lorentz invariance using atmospheric neutrinos recorded by six ORCA detection units. This principle requires consistent physical laws for observers moving at constant velocities relative to one another.

The open question: accept different answers

Ask learners: A reader says the November 4 coverage means the measurements came from a newly completed detector. Use the publication timeline and detector details to assess that claim.

One possible answer: The claim confuses publication coverage with the experiment. A preprint had already appeared in March, and the November 4 coverage reported journal publication. The measurements came from an early detector configuration, so the coverage does not show that a newly completed detector supplied them. The reading does not give exact data-collection dates.

This is an example, not the only correct answer. Look for a relevant idea, a reason and the learner’s own words. Learners can answer aloud or write one or two sentences.

Grammar to discuss

Rather than limits the claim

rather than proving that every possible violation is absent

Rather than contrasts what the analysis established with a stronger claim it did not establish. The -ing form follows the expression here.