Happy 4th of July everyone.
A bit of interesting news came out of A Rice University recently with the announcement that a research team had created a Brobdingnagian atom that’s about a millimeter in size.
Not only is the atom huge but its size caused the atom to ironically resemble the somewhat antiquated image of an atom envisaged by Danish physicist Neils Bohr in 1913 in which electrons were imagined as orbiting the atomic nucleus like a little planetary system.
Using lasers and electric fields, the research team at Rice ballooned potassium atoms until one electron was orbiting at such a distance that it bridged the gap between the microscale and the macroscale.
Lead researcher Barry Dunning and Helen Worden Professor of Physics and Astronomy stated that:
“In a sufficiently large system, the quantum effects at the atomic scale can transition into the classical mechanics found in Bohr’s model, Using highly excited Rydberg atoms and a series of pulsed electric fields, we were able to manipulate the electron motion and create circular, planet-like states.”
I remember the day I learned that the planetary image of atoms was incorrect. It was a pretty bizarre feeling but it also was my first foray into the wonderful world of quantum weirdness.
Even if the planetary atomic model isn’t strictly accurate looking through our modern perspective of atomic orbitals, it was the first successful theoretical model of the atom. Scientists of that time were puzzled that when elements like hydrogen emit light, it wasn’t a nice rainbow of colors but discrete lines of color or wavelengths. Why did atoms emit these spectral lines? Bohr’s main radical idea was that electrons could only be in specific clearly defined orbits around a nucleus. All other orbits between these allowed orbits were verboten. Bohr’s second breakthrough idea was that electrons leaped from one orbit to another, releasing or absorbing energy as they did so. This neatly explained how the spectral lines were produced.
BEAUTIFUL SPECTRUM OF THE SUN
The little bit of quantum weirdness in this process that always intrigued me was the idea that electrons apparently went from one orbit to another without really existing in between. This of course leads into one of my pet peeve expressions…A “Quantum Leap“. Casually, this means a huge increase….like “a quantum leap in technological sophistication.”
In physics it means a very small jump from one electron energy level to another. I love expressions derived from science that completely reverse the original meaning.
The domino effect of understanding that resulted from Bohr’s insight helped open new eyes onto the universe and created tools with awesome utility. Astronomical spectroscopy tells us the chemical composition and the physical properties of objects in the sky and also what their velocities are. Lasers can also be traced back to Bohr since they operate by exciting electrons into high orbits which then release their coherent light when they drop down to lower orbits.
Bohr’s atomic insights gave scientists a much deeper understanding of the physical and chemical properties of atoms and paved the way for the even deeper understanding that scientists have today. I wonder what further secrets are waiting to be revealed to future generations of scientists.
Hopefully my treatment of this topic here sparked your interest by more that just a quantum leap
p.s. My historical condolences to poor Austrian physicist Arthur Erich Haas who apparently anticipated Bohr’s breakthrough idea of quantized electron energy levels by three years only to have his ideas laughed at.
p.p.s. Happy birthday to my dizygotic twin Joe 🙂