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  1. In his "No Boundary Conditions", is Hawking stating that time is eternal?

  2. And what is the difference between Real Time and Imaginary Time?

  3. Is he saying there are two different arrows of time, and our universe began as a singularity on one of those arrows, while the other arrow already existed independently of the other?

  4. I've also read about a theory that proposes our universe might have two separate time dimensions. Can someone elaborate?

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closed as too broad by Danu, user36790, John Rennie, honeste_vivere, ACuriousMind Jun 8 '16 at 16:11

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Number 1 is true or false. The second question ....many people have wondered the difference between imaginary and real time. Question 3 and 4 are confusing and ill advised to be placed with the first two but the first two are reasonable, he seems to be asking for an intuitive feel for what this means concerning time as we experience it. My guess is almost everyone who reads a description of the theory wonders the same thing. $\endgroup$ – Sedumjoy Nov 22 '17 at 20:09
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The noboundary condition means there is no boundary that marks the end of space or time. With respect to time one might think of the lines of longitude on a globe as representing the time direction at different point in a spatial manifold modeled as the lines of latitude. As one looks further to the north, which is the big bang that eventually you look north of the north pole. From a physics perspective it means the state of the universe was not determined by any special boundary conditions, but by topology.

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