In 2011 astronomers found what they believe to be pristine clouds of primordial gas, by analyzing absorption lines in the spectra of distant quasars.

According to theoretical calculations, the primordial gases of the early universe should have been laced with tiny temperature variations, the result of acoustic waves in the rapidly expanding fireball.

The main tone and its harmonics, he said, take the form of huge acoustic waves - closely related to ordinary sound waves in air - in the hot primordial gases.

The waves are thought to have seeded the primordial gases with slight irregularities that later grew into galaxies and clusters.

The differences in pressure in the primordial gases were 1 part in 10,000, and that corresponds to a satisfyingly loud, but not lethal, 110 decibels - rock concert volume.

Consider: To an approximation, the size of bodies which condensed out of the primordial gas is inversely proportional to the frequency of their occurrence.

The engines struggled as Enterprise pulled the other ship through the tempestuous primordial gases.

Since first it condensed from primordial gas and dust, the sun had been brightening.

Minute fluctuations in the amount of energy in different places would eventually have generated sound waves, or ripples, in the primordial gases.

HVCs may explain these observations by representing a portion of the primordial gas responsible for continuously diluting the ISM.