Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

The big bang is now.

mburns (246458) writes | about 2 years ago

User Journal 0

Think about it in a careful way. Visualize a spacelike line, then extend it as a geodesic. Using a proper diagram of the universe, it is easy to show that this eventually intersects the big bang horizon. Don't be confused by convention; the Friedmann coordinates are very deceptive.

So shards of the big bang, expanding at light speed from a universal starting point in the past, are essentially contemporaneous with us.

Think about it in a careful way. Visualize a spacelike line, then extend it as a geodesic. Using a proper diagram of the universe, it is easy to show that this eventually intersects the big bang horizon. Don't be confused by convention; the Friedmann coordinates are very deceptive.

So shards of the big bang, expanding at light speed from a universal starting point in the past, are essentially contemporaneous with us.

Of course the point origin, which ought to be apparent to anyone with the use of proper inertial coordinates, implies the overall masslessness of the universe. This makes the age of the universe compatible with the value of the Hubble constant, a simple coasting outwards. And the Einstein equation (in the correct tensor rank) does allow for a negative mass background to counter the mass and energy of the material universe.

But what then, if the universe does have net mass and has decelerated, you protest. Well, then there is the boggling thought - that, out at the contemporaneous shards of the big bang, matter is continuing to enter the universe.

--
Michael J. Burns

cancel ×

0 comments

Sorry! There are no comments related to the filter you selected.

Check for New Comments
Slashdot Login

Need an Account?

Forgot your password?