Next Steps for Physicists After the Large Hadron Collider (LHC) Experiment

The Large Hadron Collider (LHC) has been a groundbreaking machine that has pushed the boundaries of our understanding of the universe. What will happen after it reaches the end of its operational life? This depends on the discoveries that will be made and the challenges that the scientific community will face. If the LHC fails to solve the mystery of dark matter, researchers will need to turn to other experiments, such as the Future Circular Collider (FCC).

Continuation and Expansion of the LHC

The LHC is expected to continue operating for at least another 15 to 20 years. During this time, scientists hope to exploit the machine further by gradually increasing its energy and mainly improving the intensity of collisions. This will enable the ongoing research into fundamental particles and forces that underpin the universe.

Among the plans for the future is the FCC, a proposed circular collider with a circumference of 100 kilometers, which aims to reach energies of nearly 100 TeV. This ambitious project would significantly broaden our ability to explore the universe at even deeper levels.

Challenges and Economic Considerations

However, building a bigger and more powerful collider like the FCC faces several challenges. There have been strong oppositions to such projects, and the current economic climate, notably influenced by the ongoing pandemic, makes it very unlikely for such a project to move forward in the near future.

LHC and B-meson Decays: A Promising Discovery

Despite the challenges, the LHC continues to yield significant discoveries. Recently, scientists observed an unequal decay of B mesons into muons and electrons. This intriguing result needs further investigation, and the LHC can be used as a B-factory to verify this finding. If confirmed, this could lead to a breakthrough, pushing us beyond the Standard Model and potentially leading to a grand-unified theory.

Further experiments are needed to firm up this discovery from its current 3-sigma level to a more conclusive 5-sigma level. The results could have profound implications for our understanding of physics. If the findings converge, indicating the presence of leptoquarks, the LHC will have made a significant contribution to our knowledge of the universe.

Potential Alternatives and Future Research Directions

In the absence of major breakthroughs from the LHC, the scientific community is likely to return to other high-priority areas of research. Potential alternatives include experiments using plasma accelerators, gravitational wave detectors, and studies focused on dark matter, neutrino mass measurements, and quantum gravity detection.

Conclusion

While the LHC is expected to continue operational for at least the next decade, the path forward for physicists will depend on the discoveries made and the challenges posed by ongoing research. The possibility of a future circular collider like the FCC remains a beacon of hope for those pushing the frontiers of physics. However, significant hurdles, including economic and political factors, must be overcome for such a project to become a reality.

The LHC’s legacy and its potential future experiments will continue to influence the course of physics, shaping our understanding of the universe for generations to come.