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New state of matter in a one-dimensional quantum gas

Taylor Kubota reports:

As the story goes, the Greek mathematician and tinkerer Archimedes came across an invention while traveling through ancient Egypt that would later bear his name. It was a machine consisting of a screw housed inside a hollow tube that trapped and drew water upon rotation.

Now, researchers led by Stanford University physicist Benjamin Lev have developed a quantum version of Archimedes’ screw that, instead of water, hauls fragile collections of gas atoms to higher and higher energy states without collapsing.

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Liquid Glass – a new state of matter

The significance of this new state as described in the original research paper:

  • Using tailor-made colloids and confocal microscopy, we study the effect of shape on the glass transition in 3D suspensions of ellipsoidal colloids.
  • Experimental data, supporting simulations, and a theoretical analysis reveal a unique state: liquid glass.
  • In liquid glasses, orientational degrees of freedom are frozen whereas translation is free.
  • Global nematic order is absent.
  • We show that, in the liquid glass state, nematic precursors as hitherto unknown structures exist.
  • In these, nematic order is suppressed by the intersection of clusters of ordered particles with differently ordered particles.
  • Our data thus give insight into the glass transition and reveal an additional state of matter.
  • The latter is expected to also have implications in liquid crystal formation.

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Notes from Matter (Wiki):

  • As such, there is no single universally agreed scientific meaning of the word “matter”. 
  • .. it (the term “Matter”) does not include massless particles such as photons, or other energy phenomena or waves such as light.
  • Matter exists in various states (also known as phases). These include classical everyday phases such as solid, liquid, and gas – for example water exists as ice, liquid water, and gaseous steam – but other states are possible, including plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma.
  • In the Standard Model of particle physics, matter is not a fundamental concept because the elementary constituents of atoms are quantum entities which do not have an inherent “size” or “volume” in any everyday sense of the word.
  • Due to the exclusion principle and other fundamental interactions, some “point particles” known as fermions (quarks, leptons), and many composites and atoms, are effectively forced to keep a distance from other particles under everyday conditions; this creates the property of matter which appears to us as matter taking up space.
  • While there are different views on what should be considered matter, the mass of a substance has exact scientific definitions.
  • Another difference is that matter has an “opposite” called antimatter, but mass has no opposite—there is no such thing as “anti-mass” or negative mass, so far as is known, although scientists do discuss the concept. Antimatter has the same (i.e. positive) mass property as its normal matter counterpart.
  • Sometimes in the field of physics “matter” is simply equated with particles that exhibit rest mass (i.e., that cannot travel at the speed of light), such as quarks and leptons. However, in both physics and chemistry, matter exhibits both wave-like and particle-like properties, the so-called wave–particle duality.

Related concept: What is the most “fundamental stuff”: