Physicists Bypass Centuries-Old Theory to Cancel Magnetic Fields, Study Says
A team of scientists has found a way to override a 178-year-old theory — allowing them to effectively cancel magnetic fields at a distance, according to a recent study published in the journal Physical Review Letters.
Physicists override centuries-old theory, canceling magnetic fields
The new work might have a lot of new applications. For example, patients suffering from neurological disorders like Parkinson's or Alzheimer's may one day acquire more accurate diagnoses. This is because the ability to cancel "noisy" external magnetic fields allows doctors to see what's going on in the brain with more accuracy.
"Earnshaw's Theorem" from 1842 places a limit on the ability to shape magnetic fields. The team from the recent study calculated a new way to circumvent this older theory, and effectively cancel other magnetic fields — which typically confuse readings in experiments, reports Phys.org.
On a practical basis, the scientists succeeded via a device they created — made of a careful arrangement of electrical wires. The distribution of wires creates additional fields, counteracting the effects of unwanted magnetic fields.
Canceling magnetic fields could advance biomedicine, quantum computing, neuroimaging
Scientists have labored to overcome this challenge for years but this team was first to the finish. While a similar effect was created at substantially higher frequencies in the past, this latest accomplishment is the first time it happened at lower frequencies and static fields — for example, biological frequencies — which could lead to a vast collection of useful applications.
To list several examples, quantum computing and technology might see applications — where "noise" from external magnetic fields can throw off experimental readings. Additionally, a practice called "transcranial magnetic stimulation" in neuroimaging activates separate areas in the brain via magnetic fields. The techniques from the paper might allow doctors to address which areas of the brain need stimulation with more precision.
The new techniques might also see applications in biomedicine — to enhance control and manipulate magnetic nanoparticles and nanorobots — which are moved through the body via external magnetic fields. This could lead to advanced drug delivery and magnetic therapies for hyperthermia.
It's an exciting time to be a physicist — with updates or overturns of old theories happening at dizzying speeds. This latest breakthrough in canceling magnetic field "noise" will surely play a pivotal role in the advancement of numerous scientific disciplines and practices.