Since it was launched two and a half decades ago, the Hubble Space Telescope has become
the ultimate time machine, delivering views of the universe all the way back to its early
days.
Hubble and other modern telescopes have aided discoveries about the evolution of galaxies,
how they are arranged across the cosmos, and where they are all headed.
Exactly how galaxies formed, in all their different shapes and sizes, remains one of
the most complex problems in all Astrophysics.
Now, scientists have developed a way to study galaxy evolution in greater detail than ever,
in a virtual universe seeded only with the laws of physics and a set of initial conditions.
This computer simulation starts just 12 million years after time zero, and evolves within
a volume 350 million light years across.
Not everything is known, including the nature of a dominant substance known as dark matter.
On the left, you can see how gravity draws dark matter into filaments, like a spider's
web.
On the right, gas heats up as it falls into a series of deepening gravitational wells
carved out by dark matter.
Within the volume, tens of thousands of galaxies take shape, mainly within the filaments of
dark matter.
Where these filaments meet, something strange begins to happen, that will affect the character
of nearly every galaxy or star.
Vast bubbles of hot gas begin to form, and expand outward.
On the left is a closer view of galaxies that are falling into one of the central regions.
On the right is the gas that envelops these galaxies.
As gravity draws these galaxies together, waves of hot gas explode outward.
This happens when giant black holes in their centers blast inflowing matter out in ferocious
winds and jets.
In time, these hot bubbles push out well beyond the central galaxies.
This has the effect of limiting the amount of gas that can fall into central regions,
allowing smaller galaxies to form on the periphery.
It also seeds the wider universe with heavier elements created in early generations of large
stars...
those elements you and I are made of.
This is the story of our galaxy and our world.
The coming together of dark and ordinary matter.
That heat up as gravity compresses them.
That leads to the production of metals in stars, that are spread throughout the cosmos.
Finally, there is light, given off by ordinary matter in a variety of wavelengths that we
can record from our tiny outpost.
In a galaxy.
And a universe that is dynamic, and complex, on all scales of space and time.