`` NEWTON: Big Bang and Randomness in Universe

 Big Bang and Randomness in Universe ``` Name: Alex Status: student Grade: 9-12 Location: MA Country: USA Date: Summer 2013 ``` Question: This is kind of an intricate question that involves multiple questions in multiple fields: 1. Is there randomness in the universe? If you knew absolutely everything about a given scenario, will you know what the result will be (will one event lead to only one possible outcome)? 2. If yes, then during the Big Bang, would the information for the whole Universe, both present, past, and future, be encoded in that first moment? 3. If yes, would it be possible to relate this to data compression in computers? If you were able to take a huge amount of information (like the whole Universe) and collapse it into a single, small piece of data (the Big Bang), and supply the computer with equations to simulate that small piece of data into the big piece of data (how the universe evolved), could you possibly be able to collapse huge amounts of data into one small package? Replies: It sounds to me that you are asking how predictable things are. If you know everything about a system at one time, can you predict how it will behave at all times in the future? The short answer is no, at least not as we currently understand physics. For instance, if you have a single radioactive atom, say polonium-218, we do not have any way to tell exactly when it will decay. We can give probabilities, and we can predict with great accuracy how quickly a sample of many Po-218 nuclei will decay, but we cannot predict which one goes when. Radioactive decay is not the only process that defies deterministic prediction, at least as quantum mechanics tells us. So as far as we can tell, even if we knew all the properties of each particle some time after the big bang, we would not know enough to predict exactly how they would evolve in the future. When you refer to "data compression" in the big bang, you seem to mean that all the information is compressed into a small volume. In fact, not only all information, but also all particles and energy, were packed into that small volume. The big bang was not static, it was a process of rapid expansion. So even if it were possible to predict everything about its future from a perfect knowledge of its present (or past), that would not exactly be a means of long-term data storage. How would you keep everything in its tiny package? Richard E. Barrans Jr., Ph.D., M.Ed. Department of Physics and Astronomy University of Wyoming Hi Alex, Thanks for the questions. Yes, there is randomness in the universe. Yes, in principle, if you knew absolutely everything about a given scenario, you would know what all future results would be. I would not say that during the Big Bang all information is encoded in a practical manner. I am unaware of how one would take a single piece of data and use it to construct a unique data set through some type of uncompression process. If it were possible--and I suspect that it is not--it would take thousands of years on today's fastest computers. I hope this helps. Please let me know if you have more questions. Thanks Jeff Grell Click here to return to the Physics Archives

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