Scientists tap into 2 new quantum methods to catch dark matter suspects

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"We are using quantum technologies at ultralow temperatures to build the most sensitive detectors to date."

A purple orbit against a dark background with a boxout showing a white room containing two crouching people attending to a complex gold machine
(Main) an illustration of dark matter at the heart of the Milky Way (inset) a supercold quantum experiment designed to hunt this elusive matter. (Image credit: Mattia Di Mauro (ESO/Fermi-Lat)/Lancaster University)

The hunt for dark matter is about to get much cooler. Scientists are developing supercold quantum technology to hunt for the universe's most elusive and mysterious stuff, which currently constitutes one of science's biggest mysteries.

Despite the fact that dark matter outnumbers the amount of ordinary matter in our universe by about six times, scientists don't know what it is. That's at least partly because no experiment devised by humanity has ever been able to detect it.

To tackle this conundrum, scientists from several universities across the U.K. have united as a team to build two of the most sensitive dark matter detectors ever envisioned. Each experiment will hunt for a different hypothetical particle that could comprise dark matter. Though they have some of the same qualities, the particles also have some radically different characteristics, thus requiring different detection techniques.

The equipment used in both experiments is so sensitive that the components have to be chilled to a thousandth of a degree above absolute zero, the theoretical and unreachable temperature at which all atomic movement would cease. This cooling must happen to prevent interference, or "noise," from the world corrupting measurements.

Related: 'Immortal stars' could feast on dark matter in the Milky Way’s heart

"We are using quantum technologies at ultra-low temperatures to build the most sensitive detectors to date," team member Samuli Autti from Lancaster University said in a statement. "The goal is to observe this mysterious matter directly in the laboratory and solve one of the greatest enigmas in science."

How dark matter has left scientists out in the cold

Dark matter poses a major issue for scientists because, despite making up about 80% to 85% of the universe, it remains effectively invisible to us. This is because dark matter doesn't interact with light or "everyday" matter — and, if it does, those interactions are rare or very weak. Or perhaps both. We just don't know.

However, because of these characteristics, scientists do know dark matter can't be composed of electrons, protons and neutrons — all part of the baryon family of particles that compose everyday matter in things like stars, planets, moons, our bodies, ice cream and next door's cat. All the "normal" stuff we can see.

The only reason we think dark matter exists at all, in fact, is that this mysterious substance has mass. Thus, it interacts with gravity. Dark matter can influence the dynamics of ordinary matter and light through that interaction, allowing its presence to be inferred. 

Astronomer Vera Rubin discovered the presence of dark matter, previously theorized by scientist Fritz Zwicky, because she saw some galaxies spinning so fast that if their only gravitational influence came from visible, baryonic matter, they would fly apart. What scientists really want, however, isn't an inference but rather a positive detection of dark matter particles. 

A composite image of the Bullet Cluster, colliding galaxy clusters that serve as one of the primary pieces of evidence that dark matter exists (Image credit: X-ray: NASA/ CXC/ CfA/ M.Markevitch, Optical and lensing map: NASA/STScI, Magellan/ U.Arizona/ D.Clowe, Lensing map: ESO/WFI)

One of the hypothetical particles currently posited as a prime suspect for dark matter is the very light "axion." Scientists also theorize dark matter could be composed of more massive (still unknown) new particles with interactions so weak that we haven’t observed them yet.

Both axions and these unknown particles would exhibit ultraweak interactions with matter, which could theoretically be detected with sensitive enough equipment. But two primary suspects mean two investigations and two experiments. This is necessary because current dark matter searches usually focus on particle masses between 5 times and 1,000 times the mass of a hydrogen atom. That means, if dark matter particles are lighter, they may be getting missed.

The Quantum Enhanced Superfluid Technologies for Dark Matter and Cosmology (QUEST-DMC) experiment is devised to detect ordinary matter colliding with dark matter particles in the form of weakly interacting unknown new particles that have masses of between 1% and a few times that of a hydrogen atom. QUEST-DMC uses superfluid helium-3, a light and stable isotope of helium with a nucleus of two protons and one neutron, cooled into a macroscopic quantum state to achieve record-breaking sensitivity in spotting ultraweak interactions.

A supercool dark matter detecting quantum experimnet is prepared in a refrigerator that will chill it to a thousandth of a degree (Image credit: https://www.lancaster.ac.uk/physics/outreach/royal-society-summer-science-exhibition/)

QUEST-DMC wouldn't be capable of spotting extremely light axions, however, which are theorized to have masses billions of times lighter than a hydrogen atom. This also means such axions wouldn't be detectable by their interaction with ordinary matter particles. 

Yet what they lack in mass, axions are posited to make up in number, with these hypothetical particles suggested to be extremely abundant. That means it's better to search for these dark matter suspects using a different signature: the tiny electrical signal resulting from axions decaying in a magnetic field. 

If such a signal exists, detecting it would require stretching detectors to the maximum level of sensitivity allowed by the rules of quantum physics. The team hopes that their Quantum Sensors for the Hidden Sector (QSHS) quantum amplifier would be capable of doing just that.

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— Tiny black holes left over from the Big Bang may be prime dark matter suspects

If you are in the U.K., the public can view both the QSHS and QUEST-DMC experiments at Lancaster University's Summer Science Exhibition. Visitors will also be able to see how scientists infer the presence of dark matter in galaxies by using a gyroscope-in-a-box that moves strangely due to unseen angular momentum.

Additionally, the exhibition features a light-up dilution refrigerator to demonstrate the ultralow temperatures required by quantum technology, while its model dark matter particle collision detector shows how our universe would behave if dark matter interacted with matter and light just as everyday matter does.

The team's papers detailing the QSHS and QUEST-DMC experiments were published the journal The European Physical Journal C and on the paper repository site arXiv. 

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Robert Lea
Robert Lea
Senior Writer

Robert Lea is a science journalist in the U.K. whose articles have been published in Physics World, New Scientist, Astronomy Magazine, All About Space, Newsweek and ZME Science. He also writes about science communication for Elsevier and the European Journal of Physics. Rob holds a bachelor of science degree in physics and astronomy from the U.K.’s Open University. Follow him on Twitter @sciencef1rst.

4 Comments Comment from the forums
  • orsobubu
    I foresee this news will reveal to be hot air, and, if it turns out there is something, it's a matter of time they discover it is a blunder, because imo there is not something like a dark matter/energy
    Reply
  • finiter
    Let them try their best. There is no dark matter or dark energy. Galaxies and clusters move at very high speeds, and so the gravity towards their centers is high compared to solar system.
    Reply
  • Jzz
    More than a hundred years ago, in 1852, Albert A Michelson and Edward Morley, designed the most sophisticated interferometer then in existence to prove or disprove the existence of the aether. Michelson, who was a gifted optical scientist had worked on the same experiment continually for more than 10 years. The null result of the final experiment caused Michelson to admit that the aether did not exist. But what if Michelson was wrong?

    Look at the following line of reasoning. The Electron is a charged particle. One of the postulates put forward by this new theory called “Gestalt Aether Theory” or simply the “A New Aether Theory” is that the electron always tries to maintain its energy of 1.6 x 10 ^-19 C intact. Therefore if the electron acquires extra energy, it immediately needs to shed that extra energy and return to its base energy level of 1.6 x10^-19 C Similarly, if an electron finds that is energy is depleted, it has immediately to absorb energy to regain its base energy level of 1.6 x 10^-19 C.

    It is interesting to speculate on how the mechanism of this shedding and absorption of energy by the electron might work. A definite possibility is that since the electron is a charged particle that it emits and absorbs electric energy in order to maintain its energy intact. The most efficient and precise manner for the electron to maintain control over the process were if the electron were to emit, not one single pulse of electric energy but a finely metred charge in small pulses. The initial pulses of energy that are emitted would be more powerful than subsequent pulses of energy, resulting in the creation of an electric dipole. Since these pulses of electric energy are separated by a small space acting as a dielectric the whole formation functions as a condenser or capacitor that can store the electric energy intact over long periods of time. Look at the following diagrams:


    In the above diagram, the process of an electron mediating its energy by emitting pulses of electric energy is depicted. It can be seen that the initial pulses of emitted electric energy are stronger than subsequent pulses of emitted pulses of electric energy. It can also be seen that the pulses of emitted electric energy are separated by space which serves as a dielectric. In the next picture, the forming of a solenoid dipole structure around the pulses of emitted electric energy is depicted:


    In this second image the pulses of electric energy emitted by the electron have transformed into an electric dipole. There are several points of interest about this formation. Firstly it should be noted that it is a stable structure, that cannot easily be disrupted, not least because of its tiny size ( 10^-15 m) in diameter and below 10^-6 m length. This dipole arrangement because of it condenser like structure, is capable of maintaining its energy intact over vast distances and times. The structure is electrically neutral and cannot easily interact with energies other the energy that it possesses. This is in effect a photon. Look at how simple this explanation is, it explains light as an emergent property of matter. Finally, the last image depicts a fully formed photon:

    Reply
  • orsobubu
    Jzz said:
    More than a hundred years ago, in 1852, Albert A Michelson and Edward Morley, designed the most sophisticated interferometer then in existence to prove or disprove the existence of the aether. Michelson, who was a gifted optical scientist had worked on the same experiment continually for more than 10 years. The null result of the final experiment caused Michelson to admit that the aether did not exist. But what if Michelson was wrong?

    Look at the following line of reasoning. The Electron is a charged particle. One of the postulates put forward by this new theory called “Gestalt Aether Theory” or simply the “A New Aether Theory” is that the electron always tries to maintain its energy of 1.6 x 10 ^-19 C intact. Therefore if the electron acquires extra energy, it immediately needs to shed that extra energy and return to its base energy level of 1.6 x10^-19 C Similarly, if an electron finds that is energy is depleted, it has immediately to absorb energy to regain its base energy level of 1.6 x 10^-19 C.

    It is interesting to speculate on how the mechanism of this shedding and absorption of energy by the electron might work. A definite possibility is that since the electron is a charged particle that it emits and absorbs electric energy in order to maintain its energy intact. The most efficient and precise manner for the electron to maintain control over the process were if the electron were to emit, not one single pulse of electric energy but a finely metred charge in small pulses. The initial pulses of energy that are emitted would be more powerful than subsequent pulses of energy, resulting in the creation of an electric dipole. Since these pulses of electric energy are separated by a small space acting as a dielectric the whole formation functions as a condenser or capacitor that can store the electric energy intact over long periods of time. Look at the following diagrams:


    In the above diagram, the process of an electron mediating its energy by emitting pulses of electric energy is depicted. It can be seen that the initial pulses of emitted electric energy are stronger than subsequent pulses of emitted pulses of electric energy. It can also be seen that the pulses of emitted electric energy are separated by space which serves as a dielectric. In the next picture, the forming of a solenoid dipole structure around the pulses of emitted electric energy is depicted:


    In this second image the pulses of electric energy emitted by the electron have transformed into an electric dipole. There are several points of interest about this formation. Firstly it should be noted that it is a stable structure, that cannot easily be disrupted, not least because of its tiny size ( 10^-15 m) in diameter and below 10^-6 m length. This dipole arrangement because of it condenser like structure, is capable of maintaining its energy intact over vast distances and times. The structure is electrically neutral and cannot easily interact with energies other the energy that it possesses. This is in effect a photon. Look at how simple this explanation is, it explains light as an emergent property of matter. Finally, the last image depicts a fully formed photon:

    Reply