By James Dacey
You can be taken on a fascinating journey through space–time if you read this month’s issue of Physics World. It contains a feature by the theoretical physicists Henrik Melbéus and Tommy Ohlsson that describes how particle-physics experiments such as the Large Hadron Collider (LHC) are being used in the hunt for extra dimensions. Melbéus and Ohlsson trace the history of theories of extra dimensions, which are known collectively as KK theories after the physicists Theodor Kaluza and Oskar Klein who first proposed the idea in the early 20th century.
KK theories represent science that goes beyond the Standard Model of particle physics. The Standard Model has been incredibly useful, but as Melbéus and Ohlsson point out, it does have a few shortcomings. For instance it cannot be used to explain dark-matter particles, which have been predicted to exist in order to explain the observations of how galaxies move under the influence of gravity. Some of the KK theories predict the existence of particles that could prove to be these elusive dark-matter particles. In their feature, Melbéus and Ohlsson describe how particle collisions at high-energy accelerators could lead to the creation of KK particles.
So far, however, the LHC has not revealed any signs of these particles, but this “no show” has helped theoretical physicists to constrain the scale of these extra dimensions – if they do indeed exist. Over the next few years, physicists will continue to analyse the abundance of data from LHC collisions in the search for KK particles. They will also be looking for other signs of physics beyond the Standard Model such as the “sparticles” predicted by supersymmetry theories.
In this week’s Facebook poll we want to know what you think will come of this hunt. Please let us know by answering the following question.
Do you think that the Large Hadron Collider will discover new physics beyond the Standard Model?
Have your say by visiting our Facebook page, and please feel free to explain your response by posting a comment below the poll.
Last week’s poll was the concluding part of a three-week series dedicated to careers in physics. We asked you to select the action that you think would be most helpful to benefit the career prospects of physics postdocs. Out of a choice of five options the most popular by a large margin was “Longer-term contracts (e.g. three years rather than one)”, which attracted 73% of responses.
The second most-popular option with 11% of votes was “More training in transferable skills”. In joint third place, with 6% each, were “Better advice on career options outside academia” and “Creating more mid-level ‘permanent postdoc’ jobs”. In last place was “Improved support for postdocs with spouses and families”, collecting just 4% of responses.
Thank you for all your responses and we hope to hear from you again in this week’s poll.