Key Takeaways:
- NASA’s Cold Atom Laboratory (CAL) is the first successful space laboratory to produce and study Bose-Einstein condensates (BECs) in microgravity.
- Unlike Earth-bound experiments lasting seconds, CAL allows scientists to study BECs for extended periods, enabling more accurate measurements.
- By studying BECs, scientists can bridge the gap between the classical and quantum worlds, offering insights into the behavior of subatomic particles.
- CAL’s atom interferometer can measure variations in Earth’s gravity, revealing information about its structure and processes like rising sea levels.
- Scientists hope to use CAL to detect axions and solitons, potentially linked to dark energy and dark matter, and understand the universe’s expansion.
NASA launched a dishwasher-sized laser box to the International Space Station. The objective is to produce the Bose-Einstein condensate, an odd fifth form of matter not seen in nature.
This kind of material is made up of clouds of a few million atoms that have been chilled to temperatures even lower than those found in interstellar space using lasers operating in a vacuum. Atoms gather together and lose their individuality at such extremely low temperatures. This helps the study of the quantum world, a subatomic space where everything is smaller than an individual atom, by researchers.
Appropriately, the laser box is named the Cold Atom Laboratory.
Despite the fact that Bose-Einstein condensates (BECs) have been produced on Earth for 25 years, studying them is challenging because gravity pulls the condensates to the ground, where they vanish in a matter of seconds.
But things are different in space. According to a research that was published in the journal Nature, the space station’s Cold Atom Lab has produced BECs reliably and successfully in microgravity. This allows scientists to study the ultracold matter for longer times than they could on Earth.
“It was recognized early on that microgravity would come in handy, and going to space would give us a lot of advantages in terms of measurement time,” David Aveline, the lead author of the study and a scientist at NASA’s Jet Propulsion Lab, told Business Insider.
More time to measure BECs translates into more accurate measurements, which could help in the investigation of dark energy and gravitational waves by scientists.
An unprecedented space laboratory
Since the discovery of the first Bose-Einstein condensate in 1995, scientists have been trying to find a way to make matter last longer than a second or two. Some researchers have attempted to produce their own microgravity environments by free-falling from a 440-foot tower with a BEC-creating apparatus. Within a rocket, some weightless experiments have also been carried out.
“It takes a lot of effort to gather a few measurements,” Aveline said.
On the other hand, the Cold Atom Laboratory (CAL) can gather data for years because of its infinite microgravity.
“We’re getting to make BECs on a daily basis, for many hours a day,” Aveline said. “CAL is completely remote-controlled. We’re running it from computers on the ground, literally inside our living rooms.”
According to Aveline, NASA’s initial objective was for CAL to operate for a full year before requiring replacement parts. But the floating laboratory just completed its second year in space, all thanks to astronauts like Christina Koch who regularly update its hardware and check in on it.
Bose-Einstein condensates teach us about the quantum world
Atoms are chilled by CAL using lasers and magnets to within a 10-billionth of a degree above absolute zero, or minus 273.15 degrees Celsius, or 459.67 degrees Fahrenheit.
Matter is made up of atoms arranged in specific orders, which result in solids, liquids, and gases. However, in 1924, physicist Satyendra Nath Bose and Albert Einstein predicted that atoms would lose their distinctiveness if they could be cooled properly. As a result, they would come together to form a single, cohesive mass lump that is about one millimeter across. This is a BEC, sometimes known as a superfluid.
The reason scientists care about BECs is because they bridge the gap between the world we can see — which is governed by classical physics — and the subatomic world, in which quantum physics reigns.
According to Aveline, “they’re like the holy grail” of quantum physics.
The smallest objects in the universe behave in a way that is explained by quantum physics. Its laws allow for the simultaneous existence of small particles like electrons in multiple locations. Therefore, probabilities that indicate the likelihood that an electron will be positioned in a specific configuration at a specific time are used by physicists to describe those electrons.
The atoms in BECs follow quantum laws, but because they’ve blobbed together, they’re large enough to be observed with a microscope — which enables scientists to measure them and observe their behavior.
What we can learn from CAL’s experiments
Koch added new hardware to CAL, including an atom interferometer, which measures variations in gravity on a planet’s surface using BECs.
Maike Lachmann, a physicist at Leibniz University, wrote to Business Insider via email, “Analyzing the gravitational field of our planet can tell us a lot about its structure (is water or stone or oil below?), and analyzing its variation can teach us about processes going on (how much does the water level of the oceans rise?).”
As per Lachmann and Aveline, there are an abundance of uses for this kind of measurement; it can aid scientists in comprehending the processes occurring beneath Earth’s surface and in mapping moons and other planets.
In addition, physicists are investigating the possibility of measuring dark energy or other possible sources of energy in the universe through the use of atom interferometry.
70% of the universe is made up of dark energy, which is the force responsible for space expansion. (The remaining portion is composed of 5% normal matter, which is what we see, and 25% dark matter, which is an invisible particle that emits a strong gravitational force.)
Some scientists believe that particles known as axions and solitons, which are not yet visible, are the source of dark energy and dark matter. According to a study published last month, BECs might be utilized to find those axions.
BECs were used in other research from 2015 and 2016 to look into various dark energy sources.
Measuring dark energy is critical, since scientists think it could be responsible for accelerating the universe’s expansion — pushing galaxies apart at an ever-faster rate.
The universe is expanding 9% faster than scientists had predicted, according to a study published last year. One Nobel Prize winner called this finding “may be the most exciting development in cosmology in decades.”
