In June 2020, the universe’s coolest laboratory confirmed that they have observed the fifth state of matter in space. Scientists on board the International Space Station created the fifth state of matter for the very first time in space. Although it sounds easy, being able to create something believed to be elusive in space is a remarkable breakthrough. Furthermore, scientists believe that this state of matter is prudent in detecting dark energy. However, before we complicate things, let us take it slowly and start from the very basics.
States of matter
A state of matter is a distinct form in which a matter can exist. As of now, scientists believe that there are as many as 15 states of matter. However, among these 15, we only consider 4 of them to be fundamental. These include solid, liquid, gas, and plasma. The reason for which is that we observe these 4 states in our daily life. But, there are elusive states of matter that we don’t observe every day. In addition to that, if at all we need to observe them, we must create extreme conditions such as absolute zero. That brings us to Bose-Einstein Condensates.
Bose-Einstein Condensates or BECs are often categorized as the fifth state of matter. Typically, this state of matter is formed when low-density bosons(in gaseous form) are cooled down to absolute zero. Once you’re able to replicate this environment, you will witness a large fraction of bosons occupying the lowest quantum state. At the same time, a microscopic phenomenon such as wavefunction interference becomes apparent, macroscopically. Hence they are believed to bridge the gap between the science of atoms, quantum mechanics, and the Newtonian approximation, general relativity. Predicted by Albert Einstein, the concept for BEC wasn’t idealized until Satyendra Nath Bose’s paper was published.
Satyendra Nath Bose
Satyendra Nath Bose was a pioneer in theoretical physics and mathematics. He was the one to architect Bose-Einstein Statistics. Needless to say, his biggest achievement was his approximation of BEC. After noticing a discrepancy in Maxwell-Boltzmann distribution, Bose wrote a letter to Einstein to translate his paper to Germany. The result was a pioneering research paper that led to the creation of “Bose-Einstein Statistics”. Since then, the two had collaborated on various scientific research.
BEC and quantum mechanics
Bose-Einstein condensates, although they look very radical, are key to straddle the line between the “macroscopic and microscopic physics”. Ever since Heisenberg and Bohr came forward with the concept of Quantum physics, the relevance of general relativity dipped. Now, BEC’s quantum property hints for the unification of both of these theories. Theoretically, when particles are cooled below absolute zero, their wave-like quantum nature will be predominant. However, this will not persist. After a few moments, this microscopic entity coalesces into a single macroscopic quantum object. “Quata” and “macroscopic” in a single sentence? Well, we are just getting started.
Cold Atom Laboratory
In 1995, a group of researchers at JILA created the first pure Bose-Einstein condensate. They were able to achieve this by using a combination of laser cooling and magnetic evaporative cooling. However, achieving near-absolute zero temperatures can be strenuous. In addition to that, Earth’s gravity limits the persistence of this matter, as they disappear in the absence of a very strong magnetic field. Hence to see if the same procedure can be carried out in outer space, NASA sent a “dishwasher-sized” lab to outer space in 2018. This was the Cold Atom Laboratory(CAL). CAL was specifically created to study the formation of Bose-Einstein condensates in a microgravity environment.
How are BECs created experimentally?
If you don’t know already, creating BEC is no easy task. For this, you will need to first need bosons(the particles having an equal number of protons and electrons). Then, you have to cool these particles to absolute zero or -273.15 °C. Collins is essential to restrict the movement of these particles. Generally, the colder the particles, the slower they move around. While they continuously reject heat, it is important to introduce a magnetic field. A strong one.
This magnetic field will restrict the boson’s movement further and cram them in a “microscopic trap”. Now, this “trap” will cause the particles’ waves to overlap into a single matter-wave. This property is known as Quantum degeneracy. As soon as this magnetic field is switched off, the atoms repel each other. Therefore BEC becomes dilute and so hard to detect. However, before the trap is released, scientists can study BECs albeit for a very short period of time.
Shortly after a successful experiment in the International Space Station, the research team head David Aveline, shared the importance of BECs. “Applications range from tests of general relativity and searches for dark energy and gravitational waves to spacecraft navigation and prospecting for subsurface minerals on the moon and other planetary bodies”, David said. If you are confused as to why dark energy is important, then only 5% of energy in the universe is normal/detectable. Whereas the rest of the composition is elusive and is composed of dark matter and dark energy. Recently, studies suggested that dark energy is derived from axions and solitons. Furthermore, their studies hint that BECs can be used to detect those axions, and hence the dark energy.
Other applications of BEC
BECs are capable of much more than the detection of dark energy. In fact, they are known to slow down the speed of light. This defunct the idea of the speed of light is constant. Furthermore, BEC will play a vital role in quantum information processing, precision measurement, and the development of optical lattices. This is not all, there are studies that suggest BEC as a potential matter for neutrino detectors. However, since we are yet to comprehensively study BECs, we haven’t used them practically. Here’s a fun fact before I wrap up: BECs are a component of crystal meth.
To sum up, BEC contains a vital clue to many mysteries. Hence their importance in the field of science. As far as the detection of dark energy is concerned, it seems as if we might have to wait a tad bit. Once the research team have studied BECs comprehenssively, we will see yet another scientific breakthrough!