Why cutting-edge braneworld theories say our universe began in a white hole

Cosmologists behind braneworld theories see our universe as being a part of a complex inter-dimensional world.

Of all the theories in cosmology about how our universe was created, the braneworld theory presents perhaps one of the most exotic, hard-to-prove and yet potentially elegant solutions to how all this came to be.


The main idea here is that our three-dimensional universe is located on a brane (short for "membrane), which is a multi-dimensional object from string-theory. This brane of ours, say the scientists, is inside a hyper-dimensional space called the “bulk” or “hyperspace”. Interaction with extra dimensions and other moving branes can have an impact on our brane, with effects other cosmological models don’t account for.

In 1999, physicists Lisa Randall and Raman Sundry introduced a braneworld theory that received considerable attention. Under their theory, there can be other universes just a microscopic distance away from ours. But this distance “is measured in some fourth spatial dimension of which we are not aware,” explains Lisa Randall in her blog post explaining the ideas. Essentially, the visible universe is embedded in a larger universe.

“Because we are imprisoned in our three dimensions we can't directly detect these other universes,” continues Randall. “It's rather like a whole lot of bugs crawling around on a big, two-dimensional sheet of paper, who would be unaware of another set of bugs that might be crawling around on another sheet of paper that could be only a short distance away in the third dimension.”

A 2013 paper by physicists Razieh Pourhasan, Niayesh Afshordi, and Robert B. Mann, called “Out of the White Hole: A Holographic Origin for the Big Bang,” proposed that our universe is like a hologram, which exists on a 3D brane that was formed as a result of the collapse of a 4D black hole in the bulk universe. The process would be similar to how stars in our universe explode in supernovas, while their inner layers collapse and form black holes. Only in this case, a universe-creating "white hole" is generated. A whole hole is a hypothetical region of spacetime that you can't enter from the outside, but matter and light can escape it.

If you notice, this model doesn't require there being being a Big Bang to start off the universe's expansion.

“Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,” said Afshordi, who led the study.

A similarly fascinating way of looking at white holes comes from physicist Nikodem Poplawski, who in 2010, while at Indiana University, proposed that when a dying star produces a black hole upon its collapse, at that same time a universe is born from a white hole on the other side of a wormhole.

This approach regards black holes and white holes as mouths of a wormhole also known as an Einstein-Rosen bridge.

In his paper, Poplawski showed through equations of the spiraling motion of matter falling into a black hole that wormholes were viable as an alternative explanation to the formation of “space-time singularities” (infinitely small points of infinite density), also predicted by Albert Einstein.

What does this mean for our own universe? It could have ”itself formed from inside a black hole existing inside another universe," explained Poplawski.

Check out this great explanation of the braneworld theory from the Caltech physicist Kip Thorne:

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What do we see from watching birds move across the country?

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  • A total of eight billion birds migrate across the U.S. in the fall.
  • The birds who migrate to the tropics fair better than the birds who winter in the U.S.
  • Conservationists can arguably use these numbers to encourage the development of better habitats in the U.S., especially if temperatures begin to vary in the south.


The migration of birds — and we didn't even used to know that birds migrated; we assumed they hibernated; the modern understanding of bird migration was established when a white stork landed in a German village with an arrow from Central Africa through its neck in 1822 — draws us in the direction of having an understanding of the world. A bird is here and then travels somewhere else. Where does it go? It's a variation on the poetic refrain from The Catcher in the Rye. Where do the ducks go? How many are out there? What might it encounter along the way?

While there is a yearly bird count conducted every Christmas by amateur bird watchers across the country done in conjunction with The Audubon Society, the Cornell Lab of Ornithology recently released the results of a study that actually go some way towards answering heretofore abstract questions: every fall, as per cloud computing and 143 weather radar stations, four billion birds migrate into the United States from Canada and four billion more head south to the tropics.

In other words: the birds who went three to four times further than the birds staying in the U.S. faired better than the birds who stayed in the U.S. Why?

Part of the answer could be very well be what you might hear from a conservationist — only with numbers to back it up: the U.S. isn't built for birds. As Ken Rosenberg, the other co-author of the study, notes: "Birds wintering in the U.S. may have more habitat disturbances and more buildings to crash into, and they might not be adapted for that."

The other option is that birds lay more offspring in the U.S. than those who fly south for the winter.

What does observing eight billion birds mean in practice? To give myself a counterpoint to those numbers, I drove out to the Joppa Flats Education Center in Northern Massachusetts. The Center is a building that sits at the entrance to the Parker River National Wildlife Refuge and overlooks the Merrimack River, which is what I climbed the stairs up to the observation deck to see.

Once there, I paused. I took a breath. I listened. I looked out into the distance. Tiny flecks Of Bonaparte's Gulls drew small white lines across the length of the river and the wave of the grass toward a nearby city. What appeared to be flecks of double-crested cormorants made their way to the sea. A telescope downstairs enabled me to watch small gull-like birds make their way along the edges of the river, quietly pecking away at food just beneath the surface of the water. This was the experience of watching maybe half a dozen birds over fifteen-to-twenty minutes, which only served to drive home the scale of birds studied.

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Scientists sequence the genome of this threatened species

If you want to know what makes a Canadian lynx a Canadian lynx a team of DNA sequencers has figured that out.

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  • A team at UMass Amherst recently sequenced the genome of the Canadian lynx.
  • It's part of a project intending to sequence the genome of every vertebrate in the world.
  • Conservationists interested in the Canadian lynx have a new tool to work with.

If you want to know what makes a Canadian lynx a Canadian lynx, I can now—as of this month—point you directly to the DNA of a Canadian lynx, and say, "That's what makes a lynx a lynx." The genome was sequenced by a team at UMass Amherst, and it's one of 15 animals whose genomes have been sequenced by the Vertebrate Genomes Project, whose stated goal is to sequence the genome of all 66,000 vertebrate species in the world.

Sequencing the genome of a particular species of an animal is important in terms of preserving genetic diversity. Future generations don't necessarily have to worry about our memory of the Canadian Lynx warping the way hearsay warped perception a long time ago.

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It is easy to see how one can look at 66,000 genomic sequences stored away as being the analogous equivalent of the Svalbard Global Seed Vault. It is a potential tool for future conservationists.

But what are the practicalities of sequencing the genome of a lynx beyond engaging with broad bioethical questions? As the animal's habitat shrinks and Earth warms, the Canadian lynx is demonstrating less genetic diversity. Cross-breeding with bobcats in some portions of the lynx's habitat also represents a challenge to the lynx's genetic makeup. The two themselves are also linked: warming climates could drive Canadian lynxes to cross-breed with bobcats.

John Organ, chief of the U.S. Geological Survey's Cooperative Fish and Wildlife units, said to MassLive that the results of the sequencing "can help us look at land conservation strategies to help maintain lynx on the landscape."

What does DNA have to do with land conservation strategies? Consider the fact that the food found in a landscape, the toxins found in a landscape, or the exposure to drugs can have an impact on genetic activity. That potential change can be transmitted down the generative line. If you know exactly how a lynx's DNA is impacted by something, then the environment they occupy can be fine-tuned to meet the needs of the lynx and any other creature that happens to inhabit that particular portion of the earth.

Given that the Trump administration is considering withdrawing protection for the Canadian lynx, a move that caught scientists by surprise, it is worth having as much information on hand as possible for those who have an interest in preserving the health of this creature—all the way down to the building blocks of a lynx's life.