The first direct evidence of cosmic inflation - a period of rapid expansion that occurred a fraction of a second after the Big Bang - also supports the idea that our universe is just one of many out there, some researchers say.
On Monday (March 17, 2014), scientists announced new findings that mark the first-ever direct evidence of primordial gravitational waves - ripples in space-time created just after the universe began.
If the results are confirmed, they would provide smoking-gun evidence that space-time expanded at many times the speed of light just after the Big Bang 13.8 billion years ago.
The bottom part of this illustration shows the scale of the universe versus time.
Specific events are shown such as the formation of neutral Hydrogen at
380 000 years after the big bang.
Prior to this time, the constant interaction between matter (electrons)
and light (photons) made the universe opaque.
After this time, the photons we now call the CMB started streaming freely.
Credit: BICEP2 Collaboration
The new research also lends credence to the idea of a multiverse.
This theory posits that, when the universe grew exponentially in the first tiny fraction of a second after the Big Bang, some parts of space-time expanded more quickly than others. This could have created "bubbles" of space-time that then developed into other universes.
The known universe has its own laws of physics, while other universes could have different laws, according to the multiverse concept.
Other researchers agreed on the link between inflation and the multiverse.
When Alan Guth and his colleagues thought up cosmic inflation more than 30 years ago, scientists thought it was untestable. Today, however, researchers are able to study light left over from the Big Bang called cosmic microwave background radiation (CMB).
In the new study, a team led by John Kovac of the Harvard-Smithsonian Center for Astrophysics found telltale signs of inflation in the microwave background.
The researchers discovered a distinct curl in the polarization pattern of the CMB, a sign of gravitational waves created by the rapid expansion of space-time just after the Big Bang.
If multiple universes exist,
they may collide with each other and leave behind
signs in the cosmic microwave background radiation, researchers say.
Credit: Stephen Feeney/UCL
Linde, one of the main contributors to inflation theory, says that if the known universe is just one bubble, there must be many other bubbles in the cosmic fabric.