Is there an upper limit to black hole density?

[newtonian]

Is there an upper limit to black hole density?<br /><br />Our universe apparently began at a higher density than any black hole extant. <br /><br />Could our universe have passed beyond an upper limit of density?<br /><br />Could such an extreme density cause inflation to take over from forces, like gravity, that would hold massive matter within black hole volume close to a singularity?<br /><br />If so, why? Could there be some lower limit of radius for gravity to be effective over dark energy? <br /><br />Comparable to a Schwartzchild (sp?) radius in reverse?<br /><br />Admittedly I do not believe this - but the questions should be asked.<br /><br />My question should be more complex:<br /><br />Is there an upper limit to energy density?<br /><br />Is there an upper limit to matter density?<br /><br />Is this effected by temperature?<br /><br />Is there an upper limit in temperature for energy?<br /><br />In quantum theory with Planck length as a minimum length and therefore a minimum diameter, is there an upper limit for the amount of energy or temperature that can be held within Planck length?

 

[nexium]

There is an upper limit of the average density inside the event horizon that is set by the Planck length indirectly and in a fuzzy manner. The highest density occurs in extremely small black holes, if any, which evaporate in less than a nano second. Solar mass black holes have millions of times less average density and a trillion solar mass black hole, if any, has trillions of times lower average density inside the event horizon than a one solar mass black hole.<br />There is little point in debating the density of the singularity at the center of the black hole, as this will likely remain forever unmeasurable. Neil

 

[harmonicaman]

I would tend to agree with member <b>Omega_Quantum.</b> Once matter has compressed to the point where space and time is completely squeezed out, (as apparently happens within a black hole), then matter has reached it's infinite density -- it cannot become any more solid; there is just no time or space available to accomodate the futher solidification of matter.

 

[derekmcd]

Is 'squeezed out' the proper analogy? I refer to it as spacetime being 'folded up' infinately tight. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[agnau]

Not being a physicist I do not know the rational behind "all black holes have infinite density". Being a realist I have found that there is no such thing as all and infinity an impractical term on the scale our finite minds can handle.<br /><br />I do know there are theories oif sub-space dimensions... allowing for a folding of what we think of as the traditional space-time foundation. In my personal belief if a black hole has a radius R and a mass M no matter how large or small the two are it is still finite. M/R, M/(R^2), M/(R^3) may be extremely small or extremely large but R will never reach 0 except in theory IMHO.

 

[agnau]

That is the theory, but can your prove 0 size in actual practice? <br /><br />Since I am an armchair mathematician and not a physicist, I will not presume that it can not be proven.

 

[doubletruncation]

<blockquote><font class="small">In reply to:</font><hr /><p>That is the theory, but can your prove 0 size in actual practice? <p><hr /></p></p></blockquote><br /><br />I don't think we can, in fact we certainly have not done so yet. There is good reason to suspect that there is something fundamentally wrong with the theories at the so-called Planck length before you reach 0 size - so I think any inferences about something smaller than that are doubtful. <div class="Discussion_UserSignature"> </div>

 

[kyle_baron]

<i><br />but if a singularity has any size at all, what prevents it from getting ever so smaller? </i><br /><br />The Strong Force. Matter will just pile up in a singularity (black hole). The electromagnetic force is 10 to the 42nd power stronger than gravity. The strong force (holds protons, neutrons, and quarks together) is 100x stronger than the electromagnetic force, making it 10 to the 44th power stronger than gravity. <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>