Why didn't the big bang collapse into a black hole?

[LeWalrus]

<p>Hi,</p><p>just wondering, if the big bang theory is correct, then at the beginning of the universe there was an enormous amount of matter and energy condensed into an incredibly small area, surely having the entire universe in such a small area would have meant the escape velocity of this point would have been greater than the speed of light thus forming a singularity.</p><p>I'm pretty sure there are caveats to my question such as normal laws of physics didn't apply or it was the fact the universe was expanding at such a rate that the concept of density was meaningless, but I would just like to know?</p><p>&nbsp;Thanks. </p>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hi,just wondering, if the big bang theory is correct, then at the beginning of the universe there was an enormous amount of matter and energy condensed into an incredibly small area, surely having the entire universe in such a small area would have meant the escape velocity of this point would have been greater than the speed of light thus forming a singularity.I'm pretty sure there are caveats to my question such as normal laws of physics didn't apply or it was the fact the universe was expanding at such a rate that the concept of density was meaningless, but I would just like to know?&nbsp;Thanks. <br />Posted by LeWalrus</DIV></p><p>I'm not sure anyone can provide a completely satisfactory explanation to your query.&nbsp; But there is a theory called inflation that attempts to describe the very early universe.&nbsp; You can find an exposition of that theory by the man who invented it, Alan Guth in <em>The Inflationary Universe.</em></p><p>There is an important distinction between black&nbsp; holes and the singularity of the primordial universe.&nbsp; In the case of black&nbsp; holes, the singularity and event horizon exist in the space-time manifold that is the universe.&nbsp; In the case of the big bang, the singularity was the universe.&nbsp; Don't take the singularities too seriously.&nbsp; Basically the singularities signal a breakdown of the theories that we use to describe nature.&nbsp; Nevertheless the distinction is in this case valid.</p> <div class="Discussion_UserSignature"> </div>

 

[vincentm]

The Big Bang didn't produce an enormous amount of matter, in which to cause a collapse. Matter as we know it, came later on during the recombination process. What initially was produced was a sea of leptons and radiation. <div class="Discussion_UserSignature"> <p>----------------------------------</p><p><br /><img id="2645f485-13bb-45be-ba60-5bfc5dfaa2a0" src="http://sitelife.space.com/ver1.0/Content/images/store/6/10/2645f485-13bb-45be-ba60-5bfc5dfaa2a0.Large.png" alt="blog post photo" width="237" height="95" /><br /> </p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The Big Bang didn't produce an enormous amount of matter, in which to cause a collapse. Matter as we know it, came later on during the recombination process. What initially was produced was a sea of leptons and radiation. <br />Posted by vincentm</DIV></p><p>True, but so what?&nbsp; That soup of matter and radiation provided all of the matter/energy that we see today.&nbsp; Remember E=mc^2.&nbsp; And with that comes gravity/space-time curvature.<br /></p> <div class="Discussion_UserSignature"> </div>

 

[vincentm]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, but so what?&nbsp; That soup of matter and radiation provided all of the matter/energy that we see today.&nbsp; Remember E=mc^2.&nbsp; And with that comes gravity/space-time curvature. <br /> Posted by DrRocket</DIV></p><p>&nbsp;Inflation overcame matter, the gist here is, the cyclic model of the big bang is dead.&nbsp; </p> <div class="Discussion_UserSignature"> <p>----------------------------------</p><p><br /><img id="2645f485-13bb-45be-ba60-5bfc5dfaa2a0" src="http://sitelife.space.com/ver1.0/Content/images/store/6/10/2645f485-13bb-45be-ba60-5bfc5dfaa2a0.Large.png" alt="blog post photo" width="237" height="95" /><br /> </p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;Inflation overcame matter, the gist here is, the cyclic model of the big bang is dead.&nbsp; <br />Posted by vincentm</DIV></p><p>The cyclic model, by which I think you mean an end to the universe in the recollapse sometimes called the Big Crunch, is in trouble, but primarily because of evidence that the expansion of the universe is accelerating.</p><p>If we did not have to contend with that accerating expansion and with so-called dark energy then a model that includes the Big Crunch would be viable, and would depend only on identifying enough matter/energy in the universe to halt the expansion and initiate a contraction.&nbsp;&nbsp;Such was the case prior to the discovery in the late 1990s of the accelerating expansion.&nbsp; As far as I know this has nothing to do with inflation.<br /></p> <div class="Discussion_UserSignature"> </div>

 

[vincentm]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The cyclic model, by which I think you mean an end to the universe in the recollapse sometimes called the Big Crunch, is in trouble, but primarily because of evidence that the expansion of the universe is accelerating.If we did not have to contend with that accerating expansion and with so-called dark energy then a model that includes the Big Crunch would be viable, and would depend only on identifying enough matter/energy in the universe to halt the expansion and initiate a contraction.&nbsp;&nbsp;Such was the case prior to the discovery in the late 1990s of the accelerating expansion.&nbsp; As far as I know this has nothing to do with inflation. <br /> Posted by DrRocket</DIV></p><p>I agree. &nbsp;</p> <div class="Discussion_UserSignature"> <p>----------------------------------</p><p><br /><img id="2645f485-13bb-45be-ba60-5bfc5dfaa2a0" src="http://sitelife.space.com/ver1.0/Content/images/store/6/10/2645f485-13bb-45be-ba60-5bfc5dfaa2a0.Large.png" alt="blog post photo" width="237" height="95" /><br /> </p> </div>

 

[SpeedFreek]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#0000ff">Such was the case prior to the discovery in the late 1990s of the accelerating expansion.&nbsp; As far as I know this has nothing to do with inflation. </font><br /> Posted by DrRocket</DIV></p><p>Inflationary theory proposes a kind of repulsive gravity field known as an inflaton field, which "got stuck" at a high value and inflated the universe, then dropped <em>towards</em> a zero-value and released its energy which became all the known matter and energy in the universe.</p><p>Is it possible that dark-energy is the remnant of that inflaton field, sitting at a value just above zero? </p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>