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yevaud
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<b>What happened before the Big Bang?</b><br /><br />What happened before the Big Bang? Does that question even make sense?<br /><br />When astronomers think about the Big Bang, in general they don’t actually mean that one singular moment when the Universe burst into being. It’s really the name given to the model used to describe what happened an infinitesimally thin slice of time after that moment.<br /><br />The problem is, right at that moment, at T=0, our laws of physics… well, they stall out. You wind up dividing by zero a lot, which causes a lot of headaches. You get things like zero volume and infinite density of matter and energy. It’s not that this moment didn’t exist physically, or that something impossible happened, it’s just that the math we currently use can’t describe it. And let me be clear: what happened after that one moment we can model fairly well. We may not have a complete picture, and the model may yet be supplanted (more on that in a moment), but we have a relatively (har har) good grasp on how the Universe behaved after T=+0.0000000000000…1 seconds. But at T=0, fuggeddaboutit. And T<0? The way the math works, that question doesn’t even make sense.<br /><br />The basic trouble is that Einstein’s relativity gives us a good description of some things (large scale gravity, for example), and quantum mechanics tells us about other things (how particles behave), but no one has ever successfully combined the two, and they must be combined to understand that First Nanonanonanonanonanosecond. Einstein himself tried, and failed.<br /><br />It’s possible, now, that this has changed.<br /><br />Martin Bojowald, an assistant professor of physics at Penn State University, may have broken through this barrier for the first time. He is working on a theory called Loop Quantum Gravity, and it combines relativity and quantum mechanics. Using this new math, something amazing happens: at T=0, the volume of the Universe is not zero, and the density is <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis: </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>