(ORDO NEWS) — In recent years, scientists have explored the possibility of using quantum principles to create the next generation of astronomy.
The basic idea is that photons can be transferred between observatories without physical connections, which are costly to build and maintain.
For astronomers, one of the biggest challenges is getting images of objects and phenomena that are difficult to see with optical telescopes (or in visible light).
This problem has been largely solved with interferometry, a technique in which multiple telescopes collect light, which is then combined to create a more complete picture.
Examples include the Event Horizon Telescope, which uses observatories around the world to take the first images of the supermassive black hole (SMBH) at the center of the M87 galaxy and Sagittarius A* at the center of the Milky Way.
At the same time, classical interferometry requires maintaining optical communication between observatories, which imposes limitations and can lead to a sharp increase in costs.
In a recent study, a team of astrophysicists and theoretical physicists proposed how these limitations could be overcome by relying on quantum mechanics.
Instead of relying on optical communication channels, they propose a way in which the principle of quantum entanglement could be used to exchange photons between observatories.
This technique is part of a growing field of research that could one day lead to “quantum telescopes.”
The study was conducted by researchers at Brookhaven National Laboratory (BNL) and Stony Brook University in New York, NY.
Additional support was provided by Steven Vintskevich, a theoretical physicist and independent researcher currently based in the United Arab Emirates.
A paper describing their findings has recently surfaced online and is being peer-reviewed for publication in the scientific journal Optica.
In classical Michelson interferometry, a beam of light is split in such a way that one beam hits a fixed mirror and the other beam hits a moving mirror.
An interference pattern is created when the reflected rays are combined again.
For the purposes of astronomy, two beams are collected by two telescopes that are separated by some distance (called basic interferometry).
But, despite its effectiveness, classical interferometry is subject to some limitations.
The main difficulty here is to maintain the stability of this optical path with very high accuracy, which must be much smaller than the photon wavelength in order to maintain the phase of the photon.
This limits practical baselines to a few hundred meters.”
In recent years, scientists have explored the possibility of using quantum principles to create the next generation of astronomy.
The basic idea is that photons can be transferred between observatories without physical connections, which are costly to build and maintain.
The key is to take advantage of quantum entanglement, a phenomenon in which particles interact and are in the same quantum state, despite being separated by a considerable distance.
Quantum telescopes were originally proposed by researchers Daniel Gottesman, Thomas Jennewane and Sarah Croke of the Perimeter Institute for Theoretical Physics and the Institute for Quantum Computing at the University of Waterloo.
“The suggestion was to use an entangled photon source and use the photon number correlations at the two stations and therefore basically eliminate the problem of photon phase stability.
Intensity interferometers are used to measure the diameters of stars using a method based on the Hanbury Brown-Twiss photon clump effect.
In our scheme, we use the same effect, only its phase dependent part, to measure the opening angle between two stars, which can now be separated by a significant angle.
On the other hand, Nomerotsky said, the second star can also be seen as a source of coherent photons for the first star, hence the reference to the Gottesman-Jennewein-Croke proposal.”
The team is currently developing a physical description that includes both options, Nomerotsky said.
This could be generalized to multiple stations and quantum protocols for processing quantum information in a “noisy” environment.
To test their concept, the team created a desktop version of a two-photon interferometer that used a narrow spectral line in two argon lamps (to simulate two stars).
As they predicted based on previous theoretical studies, the team noted the peaks of the Hanbury-Brown-Twiss photon bunching effect and channel correlation and measured its dependence on the photon phase.
The main advantage of this method is the improved angular resolution (the ability to distinguish details in objects) in telescopes.
But, as Nomerotsky explained, the long-term benefits could be immeasurable: “There could be many scientific opportunities that would benefit from a significant increase in astrometric accuracy.
Just to name a few: testing gravity theories by directly imaging black hole accretion disks, accurate parallax and cosmic distance ladders, mapping microlensing events, exoplanets, specific motions, dark matter, and more.
Of course, all this is quite long-term and will require demonstrations of proof of principle and, importantly, increased sensitivity beyond what is currently achievable.
These improvements build on progress in the development of quantum networks and quantum relays, as in the original GJC proposal.
Currently, many of these developments are being developed by companies for completely different purposes, and significant progress has been made, so this could become a reality in the foreseeable future.”
This two-photon interferometry proposal is one of many proposals for quantum telescopes in recent years.
Other examples include the MIT team’s proposal to combine interferometry with quantum teleportation to drastically increase the resolution of observatories (without using larger mirrors).
There is also a more recent idea of combining stimulated Raman adiabatic passage and pre-distributed entanglement to create a virtual interferometry telescope with a very long baseline the size of the planet Earth.
These quantum methods could allow observations to be made at previously inaccessible wavelengths and to study black holes, exoplanets, the solar system and the surfaces of distant stars in more detail.
And as efforts continue to improve the technology underlying quantum computing, applications will no doubt spread to other areas of research (such as quantum astronomy).
—
Online:
Contact us: [email protected]
Our Standards, Terms of Use: Standard Terms And Conditions.