Be informed and ahead with our real-time stock quotes, deep tools and calculators, and breaking news and. New Calculation Could Spell Trouble For a Popular Theory of the Universe's Origin. The universe began. But what did it begin from? What did it begin into? We know it began by expanding rather quickly, and ended up with lots of big galaxies made from little particles. But what happened before then? What were the laws of physics like when it all started? Famous physicists James Hartle and Stephen Hawking proposed some answers to some of these problems several decades ago. A new paper from another team of physicists analyzed Hawking and Hartle’s popular interpretation of the geometry of the big bang, and ran into some trouble. These results shed light on a problem in the universe’s beginning; a new hurdle that any future theories will need to hop over.“We tried to do the calculation more rigorously and obtained this different solution,” Job Feldbrugge, a resident Ph. D student at the Perimeter Institute, told Gizmodo. One of the biggest engineering challenges of building a towering skyscraper isn’t keeping the structure from falling over, it’s moving all the people around. Go at your own pace. Ariel Skelley/Getty Images. Victoria Moran, author of the book Main Street Vegan recommends removing one kind of animal from your diet at a time. Eventually, you should get to a point long ago in which the universe was really tiny. But questions arise as to what the baby universe looked like, including whether it was small enough to obey the laws of quantum mechanics, which seems to govern the way that the smallest particles like atoms and photons behave. There are a few ways our present universe could have started. Maybe, Hawking and Hartle thought, this condensed universe was just one point in space with a special quantum state, a so- called wave function that described the whole thing with quantum mechanics. Then, time started. Philosophy and religion require a lot more conversation for that statement, but math sort of just requires a pen and paper. ![]() ![]() ![]() This point- sized universe evolved based on the mathematics of general relativity with the initial probabilities of quantum mechanics built into its structure. The teeny, random energy fluctuations in space would then, through a quick- expanding process called inflation, turn into the large- scale density differences we see in our universe today, with galaxies and voids. Hawking and Hartle’s theory is one of several ways to account for the start of the universe without a singularity, a point of zero volume and infinite mass that doesn’t make a whole lot of sense. Other ideas, like the ones posed by Tufts cosmologist Alexander Vilenkin, don’t mind this initial singularity. But this new paper, published recently on the ar. Xiv physics preprint server, introduces a problem. When running Hawking and Hartles’ as well as Vilenkin’s, math, the new team didn’t get the teeny quantum fluctuations required to create today’s universe. Instead, those fluctuations are gigantic, and create a universe complete unlike our own.“The calculation we do results in violent gravitational waves after the Big Bang,” said Feldbrugge—enormous fluctuations in the shape of spacetime itself. The calculations conflict with the stuff we see.”Hartle wasn’t so concerned by Feldbrugge’s team’s results. ![]() It’s one of the core things that theoretical physicists are trying to do, given its importance both for understanding the origin of the universe when both sets of laws applied at the same scale, and its importance in black holes, places where gravity is so strong that light can’t escape its pull. But the main point is that Feldbrugge doesn’t think a universe beginning with the laws of quantum mechanics and relativity alone would create small fluctuations that result in a universe like ours—he thinks there has to be something else. Paul Steinhardt, physics professor at Princeton University, told Gizmodo that there are already alternative routes to go down to avoid the problems in the new paper, as well as some of the other complaints with the Hawking- Hartle model. This so- called no boundary model requires some mathematical workarounds to create a universe like ours.“What’s the alternative? It’s a non- singular bounce,” he said, a model that he and Princeton theoretical cosmologist Anna Ijjas are working on, where a past universe collapses and then turns around into our own universe, all before having to worry about the effects of quantum mechanics. I also reached out to Sabine Hossenfelder, Research Fellow at the Frankfurt Institute for Advanced Studies, who wasn’t entirely convinced by the new results. The only way to really tell what’s going on is with experiments, she said. Today, most of these theories can be proven or disproven by observing the oldest light to reach us, the cosmic microwave background. Researchers all hope that their theories’ implications will turn up as specific signatures in this data. Can Feldbrugge and the team’s work be tested? ![]() At Apple’s WWDC 2017 Craig Federighi (aka Hair Force One) announced some pretty choice upgrades to Apple Pay—upgrades that put it in direct competition with Venmo. BibMe Free Bibliography & Citation Maker - MLA, APA, Chicago, Harvard. Check out Bumble Bee's line of high quality tuna fish. Our canned and pouched tunas come in both water and oil as well as in a variety of different flavors. Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for. They’re really only at the beginning stages. And then there’s the problem of black holes, which also must obey the laws of general relativity and quantum mechanics simultaneously. Figuring them out “is certainly on our to do list,” he said. Obviously, all of this work is going to take a very, very long time. Scientists need to end up with a universe that acts like ours, but, said Hartle, “the details are up in the air.”.
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