Ancient 300-Year-Old Experiment Poised to Revolutionize Dark Matter Detection

Centuries of scientific experimentation are paving the way for a breakthrough in the hunt for new particles, particularly those believed to constitute dark matter.

In 1773, British scientist Henry Cavendish initiated an experiment aimed at unraveling the mysteries of electromagnetism, involving the measurement of electrical potential on two nested metal shells to examine interactions of charged particles.

Now, Peter Graham, a professor at Stanford University, suggests reviving Cavendish’s historic experiment could illuminate the enigmatic particles forming dark matter.

Dark matter, which constitutes a significant portion of our universe, remains poorly understood. Numerous theories have emerged regarding its composition, and experiments range from particle colliders to advanced underground detectors.

Graham and his research team are focusing on a dark matter candidate known as milli-charged particles (mCPs). True to its name, mCP has an exceptionally small charge, rendering it suitable for Cavendish’s original experimental setup.

The team proposes recreating the nested shell design, applying a voltage to the outer shell and measuring the voltage difference to detect the presence of mCPs during the experiment.

To enhance the experimental design, the team plans to incorporate an accumulator device to effectively extract all charged particles from the surrounding environment, maximizing the potential for mCP detection, according to Harikrishnan Ramani of the University of Delaware.

This innovative design is cost-effective compared to other mCP explorations, estimated at under $1 million—1,000 times less than operating a particle accelerator for a year. Preliminary calculations indicate it could be more sensitive than future collider experiments.

Researchers like Kevin Kelly from Texas A&M University believe this experimental approach could potentially outperform existing methods by a factor of 100 to 10,000, capable of detecting mCPs with even lower charges than previously thought.

According to Christopher Hill at Ohio State University, this technique may surpass some current experiments. He posits that it could accelerate the timeline for significant discoveries regarding the composition and functioning of our universe.

The research team is currently in the final stages of planning the experiment and securing funding. If successful, they aim to execute the project within two to three years, potentially offering a new avenue for studying mCPs.