[Reading Science] "E.T, Where Are You?"... Earthlings, Don't Be Lonely

Hebrew University of Israel Research Team Proposes New Hypothesis Focusing on Technological Development Level
"If Extraterrestrial Civilizations Develop, They Will Find Earth Even If It Takes Time"

Alien. Stock photo.

[Asia Economy Reporter Kim Bong-su] If life could have emerged on Earth, it is quite possible that it could have arisen somewhere else in the vast universe as well. However, extraterrestrial life has not yet been discovered. Where is everyone? This is the famous 'Fermi Paradox' in the scientific community.

Since Italian physicist Enrico Fermi proposed this theory in 1950, scientists have been engrossed in finding a solution. One of these is the rare Earth hypothesis, which claims that Earth is the only unique place with an environment capable of giving rise to carbon-based life forms. Another theory is the great filter hypothesis. While life may commonly exist, intelligent life is difficult to come by. Even on Earth, it took billions of years and five mass extinctions for intelligent life at the level of humans to appear. This theory concludes that it is nearly impossible for Earthlings to encounter intelligent extraterrestrial life capable of communication through planetary exploration or radio signal searches.

Recently, a research team from the Hebrew University of Israel attracted attention by publishing a paper on October 27 on the preprint server 'arXiv' presenting a new answer. The paper is titled "The Fermi Paradox Revisited: Technosignatures and the Contact Era." The core of this paper focuses on the technological development levels of humanity and potential extraterrestrial civilizations.

The research team suggested that even if extraterrestrial civilizations exist, their technological levels might be limited. Even if intelligent extraterrestrial life exists, their civilization might not be much more advanced than Earth's, and they could be preoccupied with solving "mundane issues" such as energy production, storage and recycling, information communication, and limited time. Even if there are one trillion potentially habitable planets in the entire universe and some of them host actual extraterrestrial civilizations, these limitations could explain why aliens cannot send messages or actively explore to announce their existence across the universe.

One of China's largest radio telescopes, 'Tianyan'. Archive photo

Therefore, the research team recommends that humanity should not be impatient but wait patiently. Instead of costly active exploration requiring billions of dollars to build spacecraft, it is better to build radio telescopes that are much cheaper and more sophisticated due to technological advances. Then, like Earthlings, wait until extraterrestrials who have developed some level of technology and civilization capable of handling radio signals send signals. The team concludes that extraterrestrials will surely respond by sending replies to messages sent from Earth or by building exploration vessels to visit Earth directly.

The problem is that even radio waves travel at only the speed of light, so it takes a long time. Radio transmissions from Earth have only been sent for about 100 years. Therefore, the range within which extraterrestrials can receive radio waves sent by humanity is about 100 light-years. It inevitably takes a long time to reach extraterrestrial civilizations that may exist thousands to tens of thousands of light-years away. Also, if extraterrestrials use the same radio means to send replies, it will take as long as the time it took for Earth's radio waves to reach them. Even if a civilization has developed spacecraft, if they travel below the speed of light, it will take even longer to reach Earth than radio waves.

Thus, the answer the research team offers to the Fermi Paradox is this: "Life on Earth, do not be lonely. Our galaxy harbors advanced civilizations. They just have not yet responded to our call."