Possible first-time detection of high-frequency gravitational waves

Australian scientists could have detected high-frequency gravitational waves: it would be the first time that this has been achieved and it would allow an important advance in the understanding of some of the most complex and mysterious phenomena in the universe, such as dark matter or black holes.

An innovative detector that aims to use quartz to capture high-frequency gravitational waves may have been able to detect such waves for the first time. The instrument and related studies have been developed by researchers at the ARC Center of Excellence for Dark Matter Particle Physics (CDM) and the University of Western Australia.

In the first 153 days of operation of the equipment, two events were detected that could, in principle, be high-frequency gravitational waves, which had not been recorded by scientists until now. These high-frequency gravitational waves may have been created by a primordial black hole or a cloud of dark matter particles, therefore their detection is crucial to shed light on both phenomena.

Gravitational waves were predicted by Albert Einstein and since then they have generated various scientific efforts aimed at their detection and definition.

A way to know more about the space
It must also be borne in mind that, as in the electromagnetic spectrum, the frequency range of gravitational waves is extremely wide and it is possible to classify them into multiple groups. One such variant is high-frequency gravitational waves.

The frequency range that characterizes gravitational wave signals provides key data on the source that emits it. For example, a very low frequency indicates that the emitting source is an object of enormous mass. According to this, its detection allows scientists to advance in the knowledge of different cosmic phenomena.

In the specific case of high-frequency gravitational waves, by detecting them it would be possible to know more about the enigmatic dark matter or about the primordial black holes, which were formed due to the extreme density of the universe at the beginning of its expansion and not as a result of the collapse of a star. Consequently, they can provide valuable information about the origin of the cosmos.

Discovery to be confirmed

According to a press release, the detector used in the new study, which was published recently in the journal Physical Review Letters, is built around a quartz crystal acoustic wave resonator (BAW).

In the center of the device there is a quartz crystal disc that is capable of vibrating at high frequencies, thanks to the acoustic waves that travel through its thickness. The team works in direct communication with a quantum interference device, which acts as an amplifier for the signals.

The researchers have detected two signals that could be high-frequency gravitational waves, although this fact still needs to be confirmed with precision. To do this, they are working to determine the nature of the signals and rule out other possibilities.

It is that the signals could also be due to the presence of certain particles, the accumulation of mechanical stress, a meteorological event or an internal atomic process. Scientists even believe it is possible that dark matter with greater mass could interact with the detector and generate signals similar to high-frequency gravitational waves.

Reference
Rare Events Detected with a Bulk Acoustic Wave High Frequency Gravitational Wave Antenna. Maxim Goryachev et al. Physical Review Letters (2021) .DOI: https: //doi.org/10.1103/PhysRevLett.127.071102