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Physics/Time Paradox


Question: In Michio Kaku's book Parallel Universes, it addresses the infinite possibility of a "time river" in correlation with Time Travel and its respective paradoxes. The one is question would be the grandfather paradox, in which if one would travel back in time and dispatch their parents his own future would would be "impossible". It has been suggested than not unlike a fork in the river, his own sequence of events that portray his future would remain unaffected rather the action would invoke a split or fork in the river to extend a parallel future to which he did not exist. Can you please prescribe further insight to this conundrum and any further literature on this subject would be much appreciated. For reference this is discussed on the last 4-5 pages of Chapter 5 in the book. V/R ZK

Sorry, you caught me on a weekend and I was away without setting my vacation settings.  You're essentially referring to a version of the many-worlds view of quantum mechanics.  I would start there.  There are so many theories of how time works and time travel that this question remains a completely open question in physics.  Basically, the interpretation you refer to suggests that for any particle interaction with multiple possible outcomes, all possible outcomes actually occur.  How is this resolved in that theoretical framework?  In this model, a separate universe is created in which each outcome actually occurred separately.  My personal feeling is that this may be used as a mathematical model, but I don't buy it.  But that's just me.  The explanation is deeply unsatisfying to me.

Beware reading too much into books that were written for the general public about science and not written for scientists.  Even a good physicist and author trying to do the important work of conveying scientific meaning to the public can't replace decades of study in the field, and the average person isn't going to do that.  When we can download such specific knowledge straight from experts to non-experts (believe it or not, biology cannot yet do this but the tools are way more plausible than time travel will be in our lifetimes) brain-to-brain then we have a shot at getting everyone to understand these more complex topics.  


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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