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View Full Version : The Big Bang and Hubbles Law



Scully
2003-Nov-20, 04:44 AM
Hi all,
If the universe was created from the Big Bang, a single point in time and space, where nothing existed before, one would presume that galaxies, stars and planets would be forming and moving away from this point in every direction. This would mean that our galaxy is only one of these many bodies, moving in one direction from this single point.

1) How does hubbles law account for this when measuring other galaxies rate of recession and their distances from us?

eg: If my initial statement is correct, would not some of the nearer galaxies be moving parralell to ours and therfore seem stationary from our perspective. Would not some be moving in the opposite direction to us therby seemingly increasing their rate of recession (our rate in one direction + their rate in the opposite direction).

2) In what direction is this single point from which the universe was created ?

eg: In what constellation would the center of the universe lie

Hope these questions evoke some lively discussion.

Cheers,
Scully :blink:

zephyr46
2003-Nov-20, 05:15 AM
As far as I understand it, time did not exisit before the big bang, thats why I call it a genisis theory. All was created at the same instant, according to the theory, I wonder too, why Andromeda is heading towards us? I guess after the creation of gravity chaotic randomness entered the equation. I think there was a galaxy cruising through the Virgo cluster not in the same course as the other galaxies in the supercluster. I'll try and find the name of the galaxy :)

Josh
2003-Nov-20, 06:04 AM
To my understanding it all goes like this...

It's based on a misconception of the Big Bang. As i've said in other threads the big bang was not an explosion in space - from a point and on outwards, as you're suggesting - rather it was an explosion of space. So no matter what part of the universe you're in everything is expanding from that point. As if every point in the universe is the centre of the universe.

Scully
2003-Nov-20, 08:29 AM
Josh, I would be interested in having a look at any websites you can reference that talks about the big bang as you explain it.
Cheers,
Scully :)

GOURDHEAD
2003-Nov-21, 03:37 PM
Here's a comment I made in the DarkMatter/Dark Energy thread that may be useful here.

[/QUOTE]If I have done the arithmetic correctly, a Hubble constant of 72 kilometers per second per kiloparsec converts to 2.3 * 10e-19 meters/sec/meter (a tenth of a billionth of a billionth) for the current rate of expansion. Since there are 4.4e+17 seconds in 14 billion years, the cumulative expansion since the big bang is 10 centimeters/meter assuming that the current measured rate is accurate and valid. Recent measurements lead some observers to believe that the expansion rate is increasing i.e., not constant. It would not be much of a stretch to assume that the Hubble constant has always been a variable and that, due to the much greater density in the early universe and the time dilation attendant thereto, the Hubble coefficient may well have been much less than unity giving the universe a much greater age. Has anyone seen an analysis of how the enormous gravitational field strength present when the universe was 10e-30 seconds old was overcome to not only prevent a black hole type collapse but also to supply the kinetic energy associated with continuing expansion and what the time dilation characteristics of this period were?

Can there be a fractal-truncation-like effect limiting expansion effects within certain gravitational field strengths such as to prohibit expansion of space within volumes occupied by us, electrons, quarks, neutrinos, etc.,? Chances are there are attributes of potential energy as functions of electric charge and magnetic field strength distributions within galaxies that we don't currently understand that will explain some of the dark energy.

I believe we are, with respect to understanding dark energy and dark matter, where the ancient astronomers were when they were adding more epicycles to their analyses of planetary orbits.

I wonder whether the Higgs boson and/or the Higgs field has a role to play here.

We have lost Occam as well as his razor. [QUOTE] :o

So far as I know there is neither theory nor observational evidence that deals with the "quantification of space stretching" to postulate why objects such as we and quarks haven't been pulled apart, or greatly expanded in volume [perhaps we are being as are our clocks and rulers] by whatever forces cause space stretching.
:unsure:

The overall expansion is modulated by "local" gravitational effects which allow specific galaxies to mutually approach or recede; however details of this modulation (or exactly what is being modulated) don't appear to be well understood.

Perhaps enormous potential energy is being stored in the space warping caused by the large number of black holes scattered throughout the universe and the expansion is caused by the universe seeking is lowest energy state. :rolleyes:

AusJosh
2003-Nov-21, 09:14 PM
Indeed, Josh (the other Josh) is correct. Its an explosion OF space.

There is no "point" where the big bang occurred because it occurred everywhere.

I like to think of it as the surface of an expanding balloon. No matter what point on the balloon you select, every other point is moving away from it.


-Josh

God
2003-Nov-30, 05:19 AM
Hi, newbie here (I know, I created everything, but I'm so old, I've got alzeimer and forgot how it all works).

Well, the Big Bang (BB) is theory and, like every theory, it remains to be proven. I never believed in the BB theory because it just does not make sense.

Ok, lots of things does not add up when you look at infinatly bigger than you, just like looking at infenatly smaller than you. When you look at smaller and smaller, momentum seem to go faster and faster to a point where everything seems to happen at once. Similarly, when looking at bigger and bigger, everything seem to slow down to a crawl (or be frozen).

There are lots of thing of the BB theory that looks soooo similar to our ancesters who tought the world was flat, and then when they realised they were living on a ball of dust, it had to be the center of the univers, etc... We are still in the same gimick. Where ever we look, the farther we look, everything seems to "go away" from us. Strangly anough, on astronomical scale, if you look 180 degrees, the speed of the fartest object will go away at the same speed. Does'nt sound odd?

It all seem so obvious to me that if, on very large radius, everything seems to drift away at the same speed, it's not because of some momentum gain from one single Big Fart, but rather that the perception of lights coming from those far distant objects must incure some similar changes, mainly about what happen to the light, the subtle changes to light induce by lenghty traveling, and what wee "see" is the effect on the perception we get from it.

I'm no scientific and I don't master the technobabble of light physics, but my simple minded logic tell me that if we can't see no further than 14 or 16 (or whatever) billions lightyears away, it must be because light simply can't shine so far. Further, if everything seem to drift further away, whetever direction you look, and that drift accelerate on a exponential level, I am inclined to think it's more logical to assess that the light is slowing down.

I have yet to learn what are the bases to say that the speed of light is constant, but I would not bet on it.

Dave Mitsky
2003-Dec-01, 09:42 AM
For information on the BB balloon analogy and misconceptions about it see http://www.astro.ucla.edu/~wright/balloon0.html

Dave Mitsky