Early in life, we start to learn the rules of this world. We memorize simple lessons 鈥� like 鈥渨hat goes up, must come down鈥� 鈥� that help us begin to make sense of our world. In time, we鈥檙e no longer surprised that rain is wet, food can spoil or the sun rises in the east and sets in the west.

But more than a century ago, scientists started to learn that all of those rules, patterns and lessons lie on a foundation that, to us, might seem filled with contradictions, confusion and chance. That foundation is . It describes how all of the material in the universe, from stars and galaxies to blades of grass and Belgian waffles, behaves at the subatomic level.

At that scale, matter has its own rules, which are so complex that they might appear divorced from the larger reality that we experience. For instance, particles can act like waves. That potential disconnect, between how we experience matter at a bulky, human scale and how matter behaves at a miniscule, subatomic scale, has kept quantum mechanics largely out of the public eye. That must change, argues , a 91探花 professor of physics, because we have entered an era where quantum mechanics plays an ever-greater role in our lives.

Morales has authored a for Ars Technica on quantum mechanics for a general audience. One article in the series is rolling out each week from Jan. 10 to Feb. 21. Morales sat down with 91探花News to talk about the series, quantum mechanics and what he hopes the public can learn about this seemingly odd and possibly intimidating realm of science.

Of all possible subjects, why did you want to write an article series on quantum mechanics for a general audience?

MM: I believe it鈥檚 important for our society to be technologically literate, that we have some shared knowledge of the technology that plays such a vital role in our lives. And that鈥檚 what we鈥檝e seen in history. One hundred years ago, electronics was at the cutting edge of science. It was this incredibly specialized field that only a handful of experts understood. Now we have university departments dedicated to teaching it while middle school students are wiring up circuits.

Our knowledge of quantum mechanics needs to evolve in the same way, because it is starting to pervade our lives and this trend will only grow with time. Quantum mechanics needs to leave the physics building and start to be more broadly understood, because otherwise the public is just going to throw its hands up and say the machines in our lives are magic. It鈥檚 not magic. There is real science behind this, and it can be made accessible for a general audience. The article series is my attempt to move in that direction.

How is quantum mechanics playing a greater role in our lives?

MM: There are lots of examples. An MRI machine at a hospital is an entirely quantum device. It has superconducting magnets that polarize all of the protons in hydrogen atoms to help generate the detailed, informative images that your doctor can use. That idea of polarizing a particle like a proton comes directly from quantum mechanics. The hard drive on your desk doesn鈥檛 work without quantum mechanics. You can now buy a TV that has quantum dots in it. And there are more examples that are coming, probably faster than we think 鈥� like quantum computing and quantum cryptography.

What makes quantum mechanics a barrier for people who aren鈥檛 experts in this field?

MM: It鈥檚 probably the math, to be blunt. A lot of complex mathematics underlies the principles of quantum mechanics. Physics students are introduced to this field largely through a mathematical lens, which is great 鈥� they need that perspective. But, I would argue that a non-expert does not. And that鈥檚 what I鈥檓 trying to do in this article series. I鈥檓 leaving the math out of it entirely.

So how do you talk about quantum mechanics without using mathematics?

MM: I think as a field we鈥檙e still trying to figure out how! For each of these articles, my approach聽 was to focus on a theme as we embark on this walking tour through the quantum mechanical woods. On each tour, I use concrete examples to illustrate a quantum mechanical effect 鈥� and give an accurate model, without the math, of what鈥檚 going on. I am not trying to focus on the 鈥渕ystery鈥� of quantum mechanics. I鈥檓 trying to illustrate by example, using things we encounter out in the world and that are also backed up by thousands of experiments in the laboratory. Then at the end of each tour we come back to the visitor center and talk about applications that are starting to appear in our lives.

What are some of these concepts from quantum mechanics that you talk about in the series?

MM: We start with 鈥淧articles move like waves but hit like particles.鈥� That means that when a particle is in motion, it鈥檚 moving like a wave. But when it hits something, like a detector, it shows up as a spot. This is true of all particles, all the time. Neutrons, which are made up of three quarks, do this. So do molecules made up of hundreds of composite particles. This is a foundation of quantum mechanics. If you鈥檙e teaching a physicist, you鈥檒l go through the mathematical steps that prove this concept. But without the math, you can use a mental picture like what I just described: moving like a wave and hitting like a particle.

Another concept I get into is that a particle has a range of 鈥渃olors,鈥� or energy, and this is closely related to the size of a particle. If you take some photons and stuff them randomly into a fiber optic cable, when we see them at the other end, we see that they鈥檝e 鈥渉eld hands鈥� along the way. All particles can be classified as either 鈥渋ntroverts,鈥� like photons that bunch up, or 鈥渆xtroverts,鈥� like electrons that avoid one another. The size of a particle wave in motion can then be extended to understand interferometric telescopes that span the earth.

These are a number of concepts that don鈥檛 get discussed much in popular media, and I try to delve into them here, because these principles will play a role in quantum-based technologies of the future.

What are some of those technologies?

MM: Too many to name! Our knowledge of quantum mechanics and advancements in manufacturing methods are allowing us to make devices with properties not seen in nature, but based on quantum mechanical concepts. It鈥檚 really revolutionary. It鈥檚 almost like we鈥檝e discovered a new superpower. Quantum electronics is an example. This field makes use of the wave-like properties of particles and has revolutionized our observations of the and the early universe.

Optical clocks are probably coming out of the lab soon and deliver an unheard-of level of timekeeping precision. A previous level of precision 鈥� that of atomic clocks 鈥� gave us GPS. That鈥檚 why the smartphone in your pocket knows where it is. I expect that these quantum-based technologies will bring about their own revolutions in how we live our lives.

And that to me, is why I feel it is so important for us to try to familiarize ourselves with quantum mechanics. I鈥檓 hoping that this series can be a chance for people to explore, even during the pandemic, and to pick up something new in a format that is hopefully fun and approachable.

For more information, contact Morales at miguelfm@uw.edu.

Today, stars fill the night sky. But when the universe was in its infancy, it contained no stars at all. And an international team of scientists is closer than ever to detecting, measuring and studying a signal from this era that has been traveling through the cosmos ever since that starless era ended some 13 billion years ago.

That team 鈥� led by researchers at the 91探花, the University of Melbourne, Curtin University and Brown University 鈥� last year in the Astrophysical Journal that it had achieved an almost 10-fold improvement of radio emission data collected by the . Team members are currently scouring the data from this radio telescope in remote Western Australia for a telltale signal from this poorly understood 鈥渄ark age鈥� of our universe.

Learning about this period will help address major questions about the universe today.

鈥淲e think the properties of the universe during this era had a major effect on the formation of the first stars and set in motion the structural features of the universe today,鈥� said team member , a 91探花professor of physics. 鈥淭he way matter was distributed in the universe during that era likely shaped how galaxies and galactic clusters are distributed today.鈥�

Before this dark age, the universe was hot and dense. Electrons and photons regularly snared one another, making the universe opaque. But when the universe was less than a million years old, electron鈥損hoton interactions became rare. The expanding universe became increasingly transparent and dark, beginning its dark age.

The starless era lasted hundreds of millions of years during which neutral hydrogen 鈥攈ydrogen atoms with no overall charge 鈥� dominated the cosmos.

鈥淔or this dark age, of course there鈥檚 no light-based signal we can study to learn about it 鈥� there was no visible light!鈥� said Morales. 鈥淏ut there is a specific signal we can look for. It comes from all that neutral hydrogen. We鈥檝e never measured this signal, but we know it鈥檚 out there. And it鈥檚 difficult to detect because in the 13 billion years since that signal was emanated, our universe has become a very busy place, filled with other activity from stars, galaxies and even our technology that drown out the signal from the neutral hydrogen.鈥�

The 13 billion-year-old signal that Morales and his team are after is electromagnetic radio emission that the neutral hydrogen emanated at a wavelength of 21 centimeters. The universe has expanded since that time, stretching the signal out to nearly 2 meters.

That signal should harbor information about the dark age and the events that ended it, Morales said.

When the universe was just 1 billion years old, hydrogen atoms began to aggregate and form the first stars, bringing an end to the dark age. The light from those first stars kicked off a new era 鈥� the Epoch of Reionization 鈥� in which energy from those stars converted much of the neutral hydrogen into an ionized . That plasma dominates interstellar space to this day.

鈥淭he Epoch of Reionization and the dark age preceding it are critical periods for understanding features of our universe, such as why we have some regions filled with galaxies and others relatively empty, the distribution of matter and potentially even dark matter and dark energy,鈥� said Morales.

The Murchison Array is the team鈥檚 primary tool. This radio telescope consists of 4,096 dipole antennas, which can pick up low-frequency signals like the electromagnetic signature of neutral hydrogen.

But those sorts of low-frequency signals are difficult to detect due to electromagnetic 鈥渘oise鈥� from other sources bouncing around the cosmos, including galaxies, stars and human activity. Morales and his colleagues have developed increasingly sophisticated methods to filter out this noise and bring them closer to that signal. In 2019, the researchers announced that they had filtered out electromagnetic interference 鈥� including from our own radio broadcasts 鈥� from more than 21 hours of Murchison Array data.

Moving forward, the team has about 3,000 hours of additional emission data collected by the radio telescope. The researchers are trying to filter out interference and get even closer to that elusive signal from neutral hydrogen 鈥� and the dark age it can illuminate.

In addition to the UW, team members include scientists at the University of Melbourne; Curtin University in Perth, Western Australia; the Commonwealth Scientific and Industrial Research Organisation in Australia; Arizona State University; Brown University; the Massachusetts Institute of Technology; Kumamoto University in Japan; and Raman University in India. The 2019 paper is based on 鈥檚 91探花doctoral thesis, with additional key 91探花contributions by physics doctoral students Michael Wilensky and Ruby Byrne, research scientist Bryna Hazelton, postdoctoral researcher Ian Sullivan and Morales. Barry is now a postdoctoral researcher at the University of Melbourne.

For more information, contact Morales at miguelfm@uw.edu.