“The Pope is watching. This is the best work…”. Perhaps these thoughts crossed your mind Guglielmo Marconi In 1932, when he installed a special antenna in the Vatican Gardens, in the presence of His Holiness Pope Pius XI. This antenna was part of A new radio link links the Vatican to the Pope’s summer residenceCastel Gandolfo. And it wasn’t just any radio link. This used microwaves and very high frequency radio waves.
Marconi was also installed A portable microwave communications system attached to the vehicle. This is what linked the Pope during his travel to the Vatican. Some claimed this was the first mobile phone, even though it was very large. Thirteen years ago, Marconi won the Nobel Prize in Physics for his contributions to wireless telegraphy. The radio era was in full swing. But when Marconi devoted himself to microwaves, he was introducing a part of the radio spectrum with very special properties.
Microwaves can carry large amounts of information. They can also cook food or interfere with enemy electronic devices. Microwaves have even helped reveal the origins of the universe.
Long before Marconi built a microwave phone for the Pope, someone had already experimented with similar frequencies. At the end of the nineteenth century, a brilliant Indian scientist named Jagadish appeared Chandra BoseToday I unfortunately forgot He developed some of the first microwave technology. Among them was the first equipment to generate millimeter waves, the same ones used by 5G devices today. In 1895, Bose demonstrated that millimeter waves could ring a bell and even set off a gun at a distance.
It can be said that Marconi owes part of his fame to Bose. On December 12, 1901, using a non-microwave frequency, the Italian inventor conducted the first transatlantic radio transmission. Sitting in a clifftop hut in Newfoundland, he listened to a whirlwind of noise in his headphones for several hours, until… He heard what he was waiting for. Beep beep beep.
Morse code for the letter S. He frantically handed the headphones to his colleague and asked, “Do you hear anything?” He could hear it. It was an incredible achievement. These radio waves traveled more than 2,000 miles from southern England, across the open sea. At that time, the long-distance radio transmission record was only 130 kilometers.
In the years that followed, Some wondered whether the transmission had actually occurred as Marconi described it. However, recent research shows that this was theoretically possible, even with primitive radio equipment. Among that equipment was a device called a coherer, a simple radio signal detector. Although the records are somewhat confusing, this knit appears to have been designed by none other than Bose. “He came with great tools.”says Bose biographer Sudipto Das.
But perhaps Bose was too ahead of his time. For one thing, at the beginning of the 20th century, there were few useful uses for microwaves that were not already possible with low-frequency radio waves. Bose stopped focusing on physics to devote himself to his greatest interest, plant physiology“He was almost forgotten,” says Das.
but, World War II gave further importance to microwave ovens. Radar allowed armies to detect enemy aircraft by bouncing radio signals off them. The microwave device is called Magnetron cavityIt was developed in the United Kingdom in 1940 One of the most powerful and effective radar technologies existing at the time. Small enough to be mounted on aircraft, its remarkable range and accuracy gave the Allied nations a significant advantage that helped them win the war.
It was so The microwave-emitting magnetron that inspired Raytheon engineer Percy Spencer to invent microwave ovens in 1945. A peanut in his pocket began to melt when he passed the magnetrons through the laboratory. When he later picked up a package of popcorn, it exploded and “exploded all over the lab,” as a Reader’s Digest article later recounted.
This happens because, at certain frequencies, microwaves excite molecules inside the food, causing them to vibrate at the same frequency. The resulting friction heats the food. In the case of microwaves, the frequency chosen is 2.4 GHz, which is the same frequency used by many Wi-Fi routers. but, Routers emit microwaves at much lower power levels than microwavesso you can’t make popcorn just by browsing the Internet.
Choosing the right frequency for cooking is very important, says Carolyn Ross of MIT. 2.4 GHz microwaves penetrate food well This frequency also allows the radiation to be uniformly absorbed by food particles. “When you get to a higher frequency, like tens of gigahertz, the penetration depth is very small, so almost anything gets in the way, even water in the air,” he explains.
Microwave devices are special in part because of their ability to interact with matter at certain frequencies.. Reheating leftover dinner may not sound very exciting, but what about using microwaves to make noises in people’s heads?
Military personnel who worked near large microwave radar installations built during World War II later reported that they felt the radar working. “The radar repeat frequency could be heard when we were close to the antenna.”One witness wrote in the 1950s.
James Lin, a professor emeritus at the University of Illinois at Chicago, heard these stories and tried to reproduce the effect in his laboratory during the 1970s. “I basically used myself as a guinea pig,” he recalls, describing how he set up the microwave antenna and pointed it directly at his head.
Lin suggested it The microwaves caused pressure waves inside his headWhich he considered sound. To prevent cooking his brain, he kept his energy levels low. “I could hear the pulse,” he says. “The fact that he’s still alive…I guess it wasn’t that bad.”. This became known as the microwave hearing effect and can help explain a series of mysterious illnesses reported by American diplomats around the world, most notably in Havana, Cuba.
Victims of the so-called Havana Syndrome have reported experiencing strange screaming soundsFeeling pressure in the ears, dizziness, nausea, and memory loss. Was the enemy directing the microwave beam at these people? Although some have rejected this hypothesis, Lin says it remains the most plausible explanation for auditory symptoms.
Microwave weapons existAlthough they tend to target machines, not people. The US military has missiles that can destroy electronic devices with microwaves, for example. Microwaves can also shoot down drones. In contrast, Lin developed ways to use microwaves in healing, using them, for example, to treat muscle diseases and arrhythmias. Regarding the latter, he says so A small microwave-emitting device can be inserted into the heartThrough catheterization, to destroy abnormal heart tissue. The technique, now widely used, is less invasive than open-heart surgery, he points out: “You just need to apply a high-energy pulse, a microwave, to burn the tissue.”
but, Microwave ovens don’t just save lives. They also helped reveal the origins of the universe. In the early 1960s, radio astronomers Arno Penzias and Robert Woodrow Wilson attempted to use a large horn-shaped antenna in New Jersey as a radio telescope. But they kept picking up annoying hiss or interference.
At some point, they thought this was due to pigeon droppings on the antenna, so they flushed the birds out and cleaned up the mess. However, the birds were not to blame. What Penzias and Wilson were hearing was the voice of the universe itself. “It’s a snapshot of the early days.”says Sean McGee of the University of Birmingham.
Penzias and Wilson discovered what we today call the cosmic microwave background radiation, a remnant of the Big Bang, when the universe exploded about 13.8 billion years ago. Penzias and Wilson together won the 1978 Nobel Prize in Physics for their work.
The residual radiation they discovered exists throughout the universe. This is due to a small portion of snowy static that appears on analog TV screens. In other words, until LED screens took hold, people were capturing the remnants of the Big Bang in their living rooms.
The satellites ended up helping astronomers map the cosmic microwave backgroundIts fluctuations are recorded by slight temperature differences. These fluctuations appear to have affected where galaxies formed as the universe expanded. “We are all the result of quantum fluctuations in the early universe, which later gave rise to galaxies,” McGee says.
Nowadays, people use microwaves to make any international calls connected via satellite. A big leap from the car-mounted equipment that Marconi installed for the Pope in the 1930s.
It’s only fitting that so many people use microwaves to communicate with each other day after day, because this is also how the universe communicates with us, helping us confirm our understanding of the greatest story of all. The story of how it all began.
*Written by Chris Baraniuk