Look hard enough at the sky and the Universe begins to look like a night city. Galaxies acquire characteristics of street lights that crowd dark matter neighborhoods, connected by gas highways that traverse the shores of intergalactic nothingness.
This map of the Universe was preordered, arranged in the smallest shudders of quantum physics moments after the Big Bang launched into an expansion of space and time about 13.8 billion years ago.
However, exactly what these fluctuations were and how they set in motion the physics that would see atoms clustered in the massive cosmic structures we see today is still far from clear.
A new mathematical analysis of the moments after a period called the inflationary era reveals that there may have been some sort of structure even within the boiling quantum furnace that filled the children’s Universe and could help us better understand its current design.
Astrophysicists at the University of Göttingen in Germany and the University of Auckland in New Zealand used a mixture of particle motion simulations and a kind of quantum and gravity modeling to predict how structures might form. in the condensation of particles after inflation.
The scale of this type of modeling is a bit mind-boggling. We are talking about masses of up to 20 kilograms squeezed into a space of barely 10-20 meters wide, at a time when the Universe was only ten-24 seconds of age.
“The physical space represented by our simulation would fit into a single proton a million times,” says astrophysicist Jens Niemeyer of the University of Göttingen.
“It is probably the largest simulation of the smallest area of the Universe that has been carried out to date.”
Most of what we know about this first stage of the Universe’s existence is based solely on this kind of mathematical break. The oldest light we can still see flashing around the Universe is cosmic background radiation (CMB), and the entire spectacle had already been on its way for about 300,000 years.
But within this faint echo of ancient radiation there are some clues as to what was happening.
CMB light was emitted as basic particles combined into atoms from the hot, dense energy soup, in what is known as the time of recombination.
A map of this background radiation through the sky shows that our Universe already had some kind of structure for several hundred thousand years. There were slightly colder chunks and slightly warmer chunks that could push matter into areas that would end up watching the stars light up, galaxies exhale, and masses build up in the cosmic city we see today.
This raises a question.
The space that makes up our Universe is expanding, that is, the Universe should have been once much smaller. Therefore, it is logical that everything we see around us was crowded in a volume too limited for such warm and fresh spots to appear.
Like a cup of baked coffee, there was no way any part would cool before reheating.
The inflationary period was proposed as a way to solve this problem. In the trillions of seconds of the Big Bang, our Universe jumped in size by an insane amount, freezing basically any variation on a quantum scale.
To say that this happened in the blink of an eye would still not do him justice. It would have started around ten36 seconds after the Big Bang, and finished in 10th32 seconds. But it was long enough for the space to adjust to proportions that would prevent small temperature variations from softening again.
The researchers’ calculations focus on this brief moment after inflation, showing how elementary particles frozen by the foam of quantum ripples at that time could have generated brief halos of matter dense enough to wrinkle space-time itself.
“The formation of these structures, as well as their movements and interactions, must have generated a background noise from gravitational waves,” says astrophysicist Benedikt Eggemeier of the University of Göttingen, the study’s lead author.
“With the help of our simulations, we can calculate the strength of this gravitational wave signal, which can be measurable in the future.”
In some cases, the intense masses of these objects could have dragged matter into primordial black holes, hypothetical objects that would have contributed to the mysterious attraction of dark matter.
The fact that the behavior of these structures mimics the large-scale agglomeration of our current Universe does not necessarily mean that it is directly responsible for the current distribution of stars, gas, and galaxies.
But the complex physics that develops between these freshly baked particles could still be visible in the sky, between that undulating landscape of twinkling lights and dark voids we call the Universe.
This research was published in Physical check D.