Before the Big Bang, Messing up Migration, Soft Body Fossils, Chemical Class for Fish Schools

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Before the Big Bang

BigBang.jpg

The Big Bang theory of the origin of our universe is widely accepted by the physics community. The idea that our universe started out as some infinitesimally small point, which expanded out to what we see today, makes a lot of sense. Except for one small thing. That initial point, called a singularity by physicists, is a physical impossibility. According to the models we have today, the temperature of the universe at that first moment would have had to be infinite, which mathematically makes no sense. Also, the singularity doesn't do a good job of explaining where all the matter and energy we see today in the universe came from. So, physicists are increasingly starting to look at other branches of physics to see what they can do to replace the singularity with a more reasonable proposition, one which can actually be explained by existing science.

Dr. Robert Brandenberger, from McGill University, is one of these researchers. He works in a field called string gas cosmology. This field uses the ideas of string theory (in which everything in the universe is composed of minuscule, sub-atomic, undetectable strings), to try to explain the early universe. According to his premise, our universe began as a very dense, very hot soup of these strings, which eventually started expanding, replacing the Big Bang singularity, and grew into what we see today.

Dr. Paul Steinhardt, from Princeton University, and Dr. Justin Khoury, from the Perimeter Institute in Waterloo, Ontario, have a different model. In their picture, our universe has been around forever, trapped in a multi-dimensional structure called a brane. This brane occasionally bumps into another brane, and when that happens, there's a giant explosion of energy and matter inside the brane itself. This causes the brane to expand, which, from inside, looks just like the Big Bang. But it avoids the singularity, since the whole universe never shrinks down to an infinitely small size.

Dr. Sean Carroll, a researcher at the California Institute of Technology, isn't convinced by either of these models. His view of the origin of the universe is that it's the offspring of another, older universe. He believes that tiny quantum fluctuations in space-time of old universes cause the spontaneous beginning of rapid expansion, called inflation, and the birth of a new entire cosmos.

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Messing up Migration

white_sparrow.jpg White Crowned Sparrow with radio transmitter - photo by Christian Ziegler

White Crowned Sparrows make an annual migration from Alaska to Southern California and Mexico. It's a remarkable feat of navigation. But a group of biologists, including Dr. Isabelle Bisson, a post-doctoral researcher in the Department of Ecology and Evolutionary Biology at Princeton University, wanted to make the job that much harder. So they captured birds in mid-migration and flew them to the East coast. Then they released them to see if they could still complete their migration. They found that the adult birds could still find their winter nesting grounds, while the juveniles could not.

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Soft Body Fossils

eurypterid_quirks.jpg Soft body fossil of a 445 million year old Sea Scorpion. Courtesy Graham Young / The Manitoba Museum.

While most of us think of Alberta as Canada's fossil hot spot, Manitoba is certainly giving it a run for its money. Dr. Graham Young, the curator of Geology and Paleontology at the Manitoba Museum in Winnipeg, and his colleagues have discovered not one, but two rich fossil deposits in central and northern Manitoba. What helps make these depots especially impressive is that they are full of soft body fossils, or impressions of softer tissued and shelled animals that don't usually get preserved in the fossil record. Now these fossils are offering paleontologists an unusual glimpse into the prehistoric past.

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Chemical Class for Fish Schools

killifish.jpg Banded Killifish - courtesy New York State Department of Environmental Conservation

Fish use chemicals released into the water for various kinds of communication. Dr. Suzie Currie, a professor of biology at Mount Allison University in New Brunswick, and her colleagues, were studying a small, minnow-like fish called the banded killifish. They found that very low levels of a common pollutant disrupted the communication these fish use to gather into protective schools. Instead, the fish tended to avoid each other, putting them at increased risk from predators.

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Theme music copyright Raphaël Gluckstein. Creative Commons License by-nc-nd-2.0
Musical stings courtesy of Beatsuite.com Music Library.