Physicists have come up with a new way to study the inside of the Universe.
An international team of scientists has proposed an unusual way to study dark matter – using atomic clocks and a network of optical laser resonators. For the first time, researchers have managed to measure how ultra-light particles affect electrons at frequencies below one hertz.
Quantum clocks measure time based on the vibrations of atoms. They have already become indispensable in GPS satellites: they help determine the location of objects with high accuracy. In the second key element of the setup, optical resonators, the laser beam is repeatedly reflected between two mirrors. The radiation frequency becomes extremely stable – such systems are already actively used in high-speed fiber optic networks.
“We are seeing wave behavior of matter – all because of the extremely small mass of the particles,” explains Ashley Caddell, a PhD student at the University of Queensland. High-precision devices act as ultra-sensitive detectors – they capture the smallest changes in fundamental constants, in particular, the mass of an electron.
Previous search methods involved placing all the sensors at one point. The instruments recorded the same wave phase, which prevented them from seeing the full picture. Moreover, if the wave effects affected two sensors in the same way, they would cancel each other out. The solution was simple: spread the measurement points far apart.
“We were able to detect tiny fluctuations in the fields that would have been lost in conventional setups because they would have cancelled each other out,” says Caddell.
The study involved two types of measurements. First, the scientists monitored the frequency fluctuations between a pair of laser resonators connected by a 2,220-kilometer-long optical fiber. This allowed them to detect spatial changes in the field. Then, the physicists analyzed data from microwave atomic clocks on GPS satellites and saw how the field changed over time.
The key was to find fluctuations lasting from two to 105 seconds, a range that corresponds to particles with masses between 10⁻¹⁹ and 2×10⁻¹⁵ electron volts. Until now, no one has experimentally tested the effect of ultra-light matter on electron mass oscillations at frequencies below one hertz. The results of the study showed that either the effect is absent or so small that modern devices cannot detect it.
"The most amazing thing is that we were able to register signals from particles that interact equally with all atoms. Previously, such phenomena could not be detected by any means," emphasizes Caddell.
Physicist Benjamin Roberts from the University of Queensland, who also participated in the work, is confident that the new method will allow us to test a variety of theories about the nature of the elusive substance and may help solve one of the main mysteries of the structure of the Universe.
An international team of scientists has proposed an unusual way to study dark matter – using atomic clocks and a network of optical laser resonators. For the first time, researchers have managed to measure how ultra-light particles affect electrons at frequencies below one hertz.
Quantum clocks measure time based on the vibrations of atoms. They have already become indispensable in GPS satellites: they help determine the location of objects with high accuracy. In the second key element of the setup, optical resonators, the laser beam is repeatedly reflected between two mirrors. The radiation frequency becomes extremely stable – such systems are already actively used in high-speed fiber optic networks.
“We are seeing wave behavior of matter – all because of the extremely small mass of the particles,” explains Ashley Caddell, a PhD student at the University of Queensland. High-precision devices act as ultra-sensitive detectors – they capture the smallest changes in fundamental constants, in particular, the mass of an electron.
Previous search methods involved placing all the sensors at one point. The instruments recorded the same wave phase, which prevented them from seeing the full picture. Moreover, if the wave effects affected two sensors in the same way, they would cancel each other out. The solution was simple: spread the measurement points far apart.
“We were able to detect tiny fluctuations in the fields that would have been lost in conventional setups because they would have cancelled each other out,” says Caddell.
The study involved two types of measurements. First, the scientists monitored the frequency fluctuations between a pair of laser resonators connected by a 2,220-kilometer-long optical fiber. This allowed them to detect spatial changes in the field. Then, the physicists analyzed data from microwave atomic clocks on GPS satellites and saw how the field changed over time.
The key was to find fluctuations lasting from two to 105 seconds, a range that corresponds to particles with masses between 10⁻¹⁹ and 2×10⁻¹⁵ electron volts. Until now, no one has experimentally tested the effect of ultra-light matter on electron mass oscillations at frequencies below one hertz. The results of the study showed that either the effect is absent or so small that modern devices cannot detect it.
"The most amazing thing is that we were able to register signals from particles that interact equally with all atoms. Previously, such phenomena could not be detected by any means," emphasizes Caddell.
Physicist Benjamin Roberts from the University of Queensland, who also participated in the work, is confident that the new method will allow us to test a variety of theories about the nature of the elusive substance and may help solve one of the main mysteries of the structure of the Universe.