"Long before it's in the papers"
June 28, 2015

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Universe may be ringing like crystal glass, scientists say

June 28, 2015
Courtesy of the University of Southern Mississippi
and World Science staff

The uni­verse may be ring­ing like a crys­tal glass, with its ex­pan­sion re­peat­ed­ly speeding up and slowing back down, cos­mol­o­gists claim.

The “ring­ing,” how­ev­er, would seem to be dy­ing down after having under­gone seven rounds of os­cill­ation.

Two graphs com­par­ing a con­ven­tion­al view and the re­search­ers' new view of cos­mic his­to­ry. The wig­gles in the bot­tom graph are ex­ag­ger­at­ed in size so they can be seen more clear­ly. Above, a NA­SA di­a­gram rep­re­sent­ing the events of the Big Bang from the be­gin­ning of time to the pre­s­ent day as de­scribed by the cur­rent, ac­cept­ed mod­el known as ΛCDM” or Lamb­da Cold Dark Mat­ter, where the Greek Lamb­da stands for Ein­stein’s “cos­mo­log­i­ con­stant”. This cos­mo­lo­g­i­cal con­stant is re­spon­si­ble for the ac­cel­er­a­tion of the uni­verse. The out­line of the “bell-shaped” uni­verse repre­s­ents its ex­pand­ing size. The tran­si­tion time is the point in time at which the bell shape shifts from go­ing in­ward to out­ward from left to right. Be­low is a  re­vised ver­sion by the au­thors of a new stu­dy. The os­cil­la­tion size is ex­ag­ger­at­ed, but the fre­quen­cy is de­scribed as rough­ly cor­rect.


“S­pace it­self… has been speed­ing up its ex­pan­sion fol­lowed by slow­ing down sev­en times since crea­t­ion,” ex­plained Har­ry Ringer­ma­cher of the Uni­vers­ity of South­ern Mis­sis­sip­pi, who co-authored a new pa­per on the re­search.

Ringer­ma­cher and co-author Law­rence Mead, al­so of the uni­vers­ity, stressed that fur­ther re­search is nec­es­sary to con­firm the find­ings.

Sci­en­tists be­lieve the uni­verse be­gan with the “big bang” and ex­pand­ed to the size it is to­day. Yet, the gra­vity of all of this mat­ter, stars, gas, ga­lax­ies, and mys­te­ri­ous dark mat­ter, tries to pull the uni­verse back to­geth­er, slow­ing down the ex­pan­sion. 

In 1978 Ar­no Al­lan Pen­zias and Rob­ert Woodrow Wil­son won a No­bel Prize for their 1964 disco­very of the the lefto­ver radia­t­ion from the Big Bang, known as the “cos­mic mi­cro­wave back­ground.”

Then in 1998 came “the find­ing that the uni­verse was not only ex­pand­ing, but was speed­ing up, or ac­cel­er­at­ing in its ex­pan­sion,” said Mead—a shock dis­cov­ery from two teams of researchers work­ing sep­ar­ately.

“A new form of mat­ter, dark en­er­gy, re­pul­sive in na­ture, was re­spon­si­ble for the speed-up. The teams led by Saul Perl­mut­ter, Ad­am Riess, and Bri­an Schmidt won the 2011 No­bel Prize in phys­ics for that disco­very.”

Ac­cord­ing to Ringer­ma­cher and Mead, the overall change from slow­ing down to speed­ing up took place around 6 to 7 bil­lion years ago, as a slew of high-tech da­ta has ver­i­fied.

But “the new find­ing sug­gests that the uni­verse has slowed down and speed­ed up, not just once, but sev­en times in the last 13.8 bil­lion years, on av­er­age em­u­lat­ing dark mat­ter in the pro­cess,” said Mead. “The ring­ing has been de­cay­ing and is now very small – much like strik­ing a crys­tal glass and hear­ing it ring down.”

The re­search is pub­lished in the April is­sue of the As­tro­nom­i­cal Jour­nal.

Ringer­ma­cher said they made the find­ing ac­ci­den­tally when, through a re­lat­ed stu­dy, they found a new way of plot­ting a clas­sic text­book graph de­scrib­ing the scale of the uni­verse against its age. The new method did­n’t de­pend on one’s pri­or choice of mod­els of the uni­verse, as had been tra­di­tion­al. 

As as­tro­no­mers had be­fore, how­ev­er, the pair used stel­lar ex­plo­sions called Type 1a su­per­novae as “s­tan­dard can­dles” for meas­ur­ing cos­mic dis­tances. The reason is that cal­cula­t­ions show all such ex­plo­sions have si­mi­lar in­her­ent bright­ness.

“An­a­lyz­ing this new plot to lo­cate the tran­si­tion time of the uni­verse,” from slow­ing to speed­ing up, Ringer­ma­cher said, “we found there was more than one such time – in fact mul­ti­ple os­cilla­t­ions.”


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The universe may be ringing like a crystal glass as its expansion has sped up and slowed back down seven times over cosmic history, cosmologists claim. The “ringing” or oscillating, however, would seem to be dying down. “Space itself… has been speeding up its expansion followed by slowing down seven times since creation,” explained Harry Ringermacher of the University of Southern Mississippi, who co-authored a new paper on the research. Ringermacher and co-author Lawrence Mead, also of the university, stressed that further research is necessary to confirm the findings. Scientists believe the universe began with the “big bang” and expanded to the size it is today. Yet, the gravity of all of this matter, stars, gas, galaxies, and mysterious dark matter, tries to pull the universe back together, slowing down the expansion. In 1978 Arno Allan Penzias and Robert Woodrow Wilson won a Nobel Prize for their 1964 discovery of the key signature of this theory, the leftover radiation from the Big Bang known as the “cosmic microwave background.” “Then in 1998 the finding that the universe was not only expanding, but was speeding up, or accelerating in its expansion was a shock when it was discovered simultaneously by east coast and west coast teams of astronomers and physicists,” said Mead. “A new form of matter, dark energy, repulsive in nature, was responsible for the speed-up. The teams led by Saul Perlmutter, Adam Riess, and Brian Schmidt won the 2011 Nobel Prize in Physics for that discovery.” According to Ringermacher and Mead, the overall change from slowing down to speeding up took place around 6 to 7 billion years ago, as a slew of high-tech data has verified. But “the new finding suggests that the universe has slowed down and speeded up, not just once, but seven times in the last 13.8 billion years, on average emulating dark matter in the process,” said Mead. “The ringing has been decaying and is now very small – much like striking a crystal glass and hearing it ring down.” The research is published in the April issue of the Astronomical Journal. Ringermacher said they made the finding accidentally when, through a related study, they found a new way of plotting a classic textbook graph describing the scale of the universe against its age that didn’t depend on one’s prior choice of models of the universe – as was traditional. As astronomers had before, however, the pair used stellar explosions called Type 1a supernovae as “standard candles” for measuring cosmic distances, based on calculations showing such explosions all have the same inherent brightness. “Analyzing this new plot to locate the transition time of the universe,” from slowing to speeding up, Ringermacher said, “we found there was more than one such time – in fact multiple oscillations.”