The universe may grow like a giant brain, according to a new computer simulation.
Image: A fundamental law of nature may govern the growth of brain networks, social networks, and the expansion of the Universe, a new computer simulation suggests Credit: WGBH Educational Foundation
The results, published Nov.16 in the journal Nature’s Scientific Reports, suggest that some undiscovered, fundamental laws may govern the growth of systems large and small, from the electrical firing between brain cells and growth of social networks to the expansion of galaxies.
"Natural growth dynamics are the same for different real networks, like the Internet or the brain or social networks," said study co-author Dmitri Krioukov, a physicist at the University of California San Diego.
The new study suggests a single fundamental law of nature may govern these networks, said physicist Kevin Bassler of the University of Houston, who was not involved in the study.
"At first blush they seem to be quite different systems, the question is, is there some kind of controlling laws can describe them?".
By raising this question, “their work really makes a pretty important contribution,” he said.
Past studies showed brain circuits and the Internet look a lot alike. But despite finding this functional similarity, nobody had developed equations to perfectly predict how computer networks, brain circuits or social networks grow over time, Krioukov said.
Using Einstein’s equations of relativity, which explain how matter warps the fabric of space-time, physicists can retrace the universe’s explosive birth in the Big Bang roughly 14 billion years ago and how it has expanded outward in the eons since.
So Krioukov’s team wondered whether the universe’s accelerating growth could provide insight into the ways social networks or brain circuits expand.
Brain cells and galaxies
The team created a computer simulation that broke the early universe into the tiniest possible units — quanta of space-time more miniscule than subatomic particles. The simulation linked any quanta, or nodes in a massive celestial network, that were causally related. (Nothing travels faster than light, so if a person hits a baseball on Earth, the ripple effects of that event could never reach an alien in a distant galaxy in a reasonable amount of time, meaning those two regions of space-time aren’t causally related.)
As the simulation progressed, it added more and more space-time to the history of the universe, and so its “network” connections between matter in galaxies, grew as well, Krioukov said.
When the team compared the universe’s history with growth of social networks and brain circuits, they found all the networks expanded in similar ways: They balanced links between similar nodes with ones that already had many connections. For instance, a cat lover surfing the Internet may visit mega-sites such as Google or Yahoo, but will also browse cat fancier websites or YouTube kitten videos. In the same way, neighboring brain cells like to connect, but neurons also link to such “Google brain cells” that are hooked up to loads of other brain cells.
The eerie similarity between networks large and small is unlikely to be a coincidence, Krioukov said.
"For a physicist it’s an immediate signal that there is some missing understanding of how nature works," Krioukov said.
It’s more likely that some unknown law governs the way networks grow and change, from the smallest brain cells to the growth of mega-galaxies, Krioukov said.
"This result suggests that maybe we should start looking for it," Krioukov told LiveScience.
This new image of the luminous blue variable Eta Carinae was taken with the NACO near-infrared adaptive optics instrument on ESO’s Very Large Telescope, yielding an incredible amount of detail. The images clearly shows a bipolar structure as well as the jets coming out from the central star. The image was obtained by the Paranal Science team and processed by Yuri Beletsky (ESO) and Hännes Heyer (ESO). It is based on data obtained through broad (J, H, and K; 90 second exposure time per filters) and narrow-bands (1.64, 2.12, and 2.17 microns; probing iron, molecular and atomic hydrogen, respectively; 4 min per filter).
Regarding the recent NASA Kepler discovery of what is being dubbed the closest “Earth-like” or “Earth twin” planet…
"This planet Kepler-186f orbits a star that’s cooler and dimmer than the sun. So while we may have found a planet that’s the same size as Earth, and receives the same amount of energy to what Earth receives, it orbits a very different star. So, perhaps, instead of an Earth twin, we have discovered an Earth cousin," said NASA Ames Research Scientist Thomas Barclay, of BAERI.
Standing on the surface of Kepler-186f, this is how the view may appear. Credit: Danielle Futselaar
Not to downplay this hype, however. There’s no mistaking it…THIS IS A MAJOR MOMENT IN HUMAN HISTORY.
Astronomers have discovered planets that reside in the Goldilocks or Habitable Zone of solar systems outside of our own. This, however, is the first confirmed find of a planet as close in size (10% larger) to that of Earth.
"This is the best case for a habitable planet yet found. The results are absolutely rock solid. The planet itself may not be [rocky], but I’d bet my house on it. In any case, it’s a gem," Geoff Marcy, Astronomer at the University of California Berkeley told Space.com.
Kepler-186f’s potential for liquid water and perhaps, life, is what make its existence that much more intriguing. [view larger]
"Some people call these habitable planets, which of course we have no idea if they are, we simply know that they are in the habitable zone, and that is the best place to start looking for habitable planets," San Francisco State University astronomer and study co-author Stephen Kane said in a statement to Space.com.
"The four companion planets — Kepler-186b, Kepler-186c, Kepler-186d and Kepler-186e — whiz around their sun every four, seven, 13 and 22 days, respectively, making them too hot for life as we know it. These four inner planets all measure less than 1.5 times the size of Earth," noted in an official statement from NASA.
Geoff Marcy said, "This planet is modestly illuminated by its host star, a red dwarf. This planet basks in an orange-red glow from that star, much [like what] we enjoy at sunset."
Kepler-186f is 1 of 5 planets around its host star, which is a red dwarf, taking 130 days to orbit. As seen in the comparison-worthy artistic rendering above, Kepler-186f and our Earth would share similar views at dawn and dusk.
Whether or not Kepler-186f does contain life, one thing is for certain, there’s a whole lot more space to explore. If Carl were here to share in these continued findings, I believe he’d revert to a self-quoted suggestion from his novel-turned-motion-picture, Contact…
“The universe is a pretty big place. If it is just us, seems like an awful waste of space.”
Stay curious. This is just the beginning.
Right now, 500 light years away from Earth, there’s a planet that looks a lot like our own. It is bathed in dim orangeish light, which at high noon is only as bright as the golden hour before sunset back home.
NASA scientists are calling the planet Kepler-186f, and it’s unlike anything they’ve found. The big news: Kepler-186f is the closest relative to the Earth that researchers have discovered.
It’s the first Earth-sized planet in the habitable zone of another star—the sweet spot between too-hot Mercury-like planets and too-cold Neptunes— and it is likely to give scientists their first real opportunity to seek life elsewhere in the universe. “It’s no longer in the realm of science fiction,” said Elisa Quintana, a researcher at the SETI Institute.
But if there is indeed life on Kepler-186f, it may not look like what we have here. Given the redder wavelengths of light on the planet, vegetation there would sprout in hues of yellow and orange instead of green.
Read more. [Image: NASA Ames/SETI Institute/JPL-Caltech]