Recent content by G Hathaway

So, in a thought experiment, let us place a clock at the point of the big bang. We are in motion relative to the point of the big bang pointed to by the CMBR. Our age-of-the-universe -- our proper time -- our 13.7 billion years -- is different from and less than the proper time of that...

As I understand it (on another message board) Bob K was banned. (For "crackpottery" it was claimed.) So he is unlikely to read this response. Should you wish to engage him (not recommended -- he is totally dogmatic that there is an absolute time) I could direct you to the right message board.

In this article, http://www.astro.ucla.edu/~wright/cosmo_02.htm, I note the author's use of the term "proper time." Is this possibly Bob K's "absolute time"?

I found http://www.astro.ucla.edu/~wright/cosmo_03.htm Does the article (at the heading Flatness-Oldness problem) conclude that at the largest scale the universe is flat to within 1 in 447,225,917,218,507,401,284,016? If so, what would that mean?

Never having heard of deconstructionism before, I find it hard to judge whether I inadvertently engaged in it.

That is interesting that you say that the earth-twin-clock slows down from the point of view on the ship. And at the same time, the space-twin-clock slows down from the point of view on earth. They both slowed down by the same amount. How could they be different (twin paradox) when brought...

When the twin of twin paradox fame returns to his twin, his clock has proceeded at a different rate from his life processes. That clock having been adjusted to compensate for the trip. It has been adjusted so when he returns to his twin, the clocks agree. And, of course, he knows just how old...

We can use a clock to measure time locally. We can correct for relative motions of any similar clock, right? Is it not theoretically possible to "synchronize" relative to, say, our Earth rather than our lab? And to synchronize relative to, say, our solar system? Or, say, our galaxy? Our...

The sphere metaphor is one of extrinsic curvature. Sorry, but that doesn't help; been arount that tree. Even not in free fall, particles are going downhill relative to all four forces. Their going is probabilistic. The very word -- curvature -- is a spatial thing. The concept has...

I will factor in the idea of density into my growing definition of intrinsic curvature. Space becomes more compressed, in a sense. My imagination is limited when I attempt to visualize other than flat 3-space. For example, in the density analog I find that I understand 'density' relative...

Since mathematics is derived from human experience via metaphor we feel that we can trust it to model reality. (See Lakoff and Nunez, Where Mathematics Comes From) Models of the solar system with the Earth as the center led to a mathematics of cycles and epicycles that fit reality quite...

I will try to understand what intrinsic curvature could mean. It is a little like the problem of an expanding universe. If all scales are expanding uniformly at all scales then the expansion would be undetectable. There is a difference between a circle (or other intersection of a plane...

We can mathematically model reality. The metric tensor is not reality. In what dimension is space curved? Sure, we can see the 2-surface when folded into a sphere is a closed 3-space. It is curved or folded or closed in a higher dimension. What is the dimension if it is 4-space that is...

What is "coordinate time"? I mean, does a rotating frame of reference work?

If 4-D spacetime is curved doesn't that imply there must be a 5th physical dimension in which this, our 4-D spacetime, is curved?