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#55
Dec911, 06:16 PM

P: 45

They say it's hard to imagine infinite space.. It could be a 4th dimension. BUT, if you did walk all the way to the edge of space and took one more step, you'd be right back where you started. It's like if someone couldn't grasp the concept of a 3 dimensional sphere. You'd put him on earth and he'd walk and walk and sooner or later he'd get right back where he started, bewildered. Thus may be our ability to conceive how we could get to the edge of space, and be right back where we were.



#56
Dec911, 06:19 PM

P: 45

The protons and electrons acting like Solar Systems in the Bohr's atom model is what lead to all that science fiction in the 30's and after: universes within universes. Our modern concept of how atoms are and operate is very different from what you learned in highschool science.



#57
Dec911, 07:09 PM

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#58
Dec1011, 01:44 AM

P: 186

There’s no need for an edge if the universe is finite or compact. It’s just like on Earth. You can travel in a straight line on Earth and you can come back to where you started from. The difference is that on Earth you’re limited to a 2D surface, but the Universe is 3D.



#59
Dec1011, 05:26 AM

P: 100




#60
Dec1011, 07:56 AM

P: 45

And that's a very thought provoking statement that the Earth is 3D with a 2D surface, perhaps the universe is 4D with a 3D "surface"? (That's some string theory and other theories right?) Anyway, no need to speculate but it's a extremely interesting topic, and it's always good for our minds to think. :) 


#61
Dec1011, 11:55 PM

P: 186

“According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly.” How can you have rapid expansion in size if the Universe is infinite? 


#62
Dec1111, 01:02 AM

P: 186




#63
Dec1111, 04:30 AM

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#64
Dec1111, 06:03 AM

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#65
Dec1311, 12:01 AM

P: 186

I can’t help but think that the BB singularity had some properties similar to Black Holes, and Black Holes can bend spacetime. It’s possible that space was compact near the Big Bang, with all the mass/energy of the Universe confined to a point singularity. 


#66
Dec1311, 01:53 AM

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#67
Dec1311, 08:20 AM

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#68
Dec1611, 10:57 AM

P: 366

Take a picture of any amount of time your camera will let you. We can make the illusion of photons going the opposite direction in time by making a negative. In this negative view the objects appear as holes and space the source of photons. Both pictures are of edges in my universe the edge is between inner spacetime and outer spacetime. Hope this helps. 


#69
Dec1611, 11:44 AM

P: 728

Chalnoth, what are you thoughts on the following?
"If you were traveling at the speed of light and turned a flashlight on, what would happen to the light? Relative to you, the light from your flashlight would still be moving at 3 x 10^8 m/s. To allow this to happen, your perception of time slows down the faster you move and you gain more mass (E=mc^2)." I believe the above is correct. So my question is, at the beginning of the BB when all particles were moving very fast, would time effects like the above example effect our estimates for the rate of inflation, or even our estimates for the age of the universe since particles were moving very fast for quite a while? I am very uncertain of which relativitic frames of reference apply in this case. Thanks! 


#70
Dec1611, 11:58 AM

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#71
Dec1611, 12:03 PM

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