Can Optical Clock Detect Dark Matter?

Can Optical Clock Detect Dark Matter?

An optical atomic clock has the potential to prove the existence of dark matter with utmost precision. How do we know this? Well, that’s what a paper submitted by researchers from the University of Colorado, to the journal Physical Review Letters, says at least. So how did they do it? Are we closer to proving the existence of dark matter now?

Crux of the Matter

What Is An Optical Clock?
All clocks are based on stable oscillators, from a grandfather clock that uses pendulum oscillators, or a sundial clock, that relies on the steady rotation of the earth. In an optical clock, the steady oscillator is the laser.

How Does This Clock Tick?
The laser in an optical clock is regulated using the quantum oscillations of atoms, making them the most precise clocks in existence till date. These clocks tick approximately a quadrillion (one million billion) times per second.

How Accurate Is It?
These optical clocks are so accurate, that scientists estimate 20 billion years, longer than the known age of the Universe (13.77 billion years since big bang), before it leads or lags by even a second.

Where Can It Be Used?
To build a gravitational wave telescope. Gravitational waves passing through a region of space, change the frequency of light waves slightly, traveling through the same region. If light is sent from an optical clock on one satellite to another one on a nearby satellite, the clocks will detect this change in light frequency and sense the effect of the gravitational wave.

What Is Dark Matter?
Accounting for 85% of the matter in the universe, dark matter is composed of particles that don’t absorb, reflect, or emit light. Thus, they cannot be detected by observing electromagnetic radiation.

So Can Optical Clock Detect Dark Matter Too?
Yes. The existence of dark matter is indirectly evident from the gravitational effects it has on the cosmological scale, via galaxies and stars. Another way is by observing the oscillation of fundamental physics constants like α.

History Of Finding Dark Matter
Previous works involved large-scale studies, such as those conducted at the CERN’s Large Hadron Collider (LHC), the world’s largest and most powerful particle accelerator and via the god particle, Higgs boson.

What Is The New Research About?
The University of Colorado team lead by Jun Ye used a state of the art kit – strontium optical clock, a hydrogen maser, and its own cryogenic cavity – to try and capture possible interactions between dark matter from quantum physics and particles from the standard model of physics.

The optical clock first observed variations in alpha (α). Then it compared the frequency of the strontium atoms in the clock to those in the silicon cavity, which allows electromagnetic waves to bounce inside its chambers, which creates a standing wave. Furthermore, this data was also compared to the frequency of a hydrogen maser, a frequency standard using a hydrogen atom as reference.

  • The family of Marie Curie has 5 Nobel Prize winners. Marie Curie won two Nobel Prizes in Chemistry in 1911 and in Physics in 1903 along with her husband, Pierre Curie. Her daughter Irene Curie and her son-in-law Frederic Joliot won Nobel Prize in Chemistry in 1935. Her son-in-law, Henry Labouisse won Nobel Peace Prize in 1965
  • A massive lump of crystallized diamond called BPM 37093 is the latest diamond in the galaxy. It is also known as Lucy after The Beatles’ song Lucy in the Sky with Diamonds and weighs in at a 10 billion-trillion-trillion carats.
  • On March 20, 2013, Voyager 1 became the first human-made object to leave the Solar System and is now the farthest human-made object from Earth, currently 124.34 Astronomical Units away.
  • The Voyager Golden Records are two phonograph records that were included aboard both Voyager spacecraft launched in 1977. The records contain sounds and images selected to portray the diversity of life and culture on Earth, and are intended for any intelligent extraterrestrial life form who may find them. 
  • Higgs Boson is named after physicist Peter Higgs, who in 1964, along with five other scientists, proposed the Higgs mechanism to explain why particles have mass.

Dark Matter Found Missing in 19 Galaxies

Dwarf galaxy NGC 5477, seen here in this image from Hubble

According to astronomers, nineteen newly discovered dwarf galaxies seem to be missing their dark matter. This discovery may have a direct inference for revisiting the theories about both dark matter and galaxy formation.

Crux of the Matter
  • Lead author Qi Guo of the Chinese Academy of Science and her team explored the nature of 324 dwarf galaxies using data from the Arecibo Observatory in Puerto Rico and the Sloan Digital Sky Survey.
  • These peculiar 19 galaxies are found to be filled with regular matter, including the protons, neutrons, and electrons, which are just sufficient to explain the motions of the galaxies’ hydrogen.
  • Until now, dark matter was thought to be a key ingredient in galaxy formation, with its gravity pulling together atoms of gas to form galaxies and new stars.
  • Now further studies would be conducted to rediscover the mystery behind kickstarting star formations.

Dark Matter is a form of matter thought to account for approximately 85% of the matter in the universe and about a quarter of its total energy density. It is called dark because it does not appear to interact with observable electromagnetic radiation, such as light, and so it is undetectable by existing astronomical instruments.It is additionally classified as “cold”, “warm”, or “hot” according to its velocity. More Info