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How can the Big Bang singularity exist if it has zero volume? I tried googling to find the answer - no help.

Can someone give a general idea how can the big bang singularity exist even if it has zero volume. Please try to avoid post graduate concepts as I am only familiar with high school physic.

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Hashir Omer
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    Sorry, but your question is completely unclear to me. For all we know, electrons are point particles with zero volume, yet they exist... – Danu Sep 27 '14 at 07:52
  • Hashir, can you explain why you think something with zero volume cannot exist? Or is it specifically tied to a singularity somehow? – BMS Sep 27 '14 at 08:12
  • As Danu says, at least from the point of standard particle physics, all matter and energy is carried by zero-volume points. – Void Sep 27 '14 at 08:45
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    What singularity are you asking about -- the singularity at the center of a black hole, the initial singularity of big bang theory, or something else? – David Hammen Sep 27 '14 at 08:54
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    I am asking about the initial singularity before big bang. – Hashir Omer Sep 27 '14 at 09:10
  • It's not clear that there was even such a thing as "time" in the very early phases of the big bang, so the qualifier "before" has no discernible physical meaning, at this time. There is also no hint in physics that there ever was a singularity besides the one found on pieces of paper scribbled on by theoreticians during the 20th and early 21st century. – CuriousOne Sep 27 '14 at 15:56
  • The Big Bang had a minimum radius of $R_{min} = 5.78398\times10^5\text{ meter}$, so I guess it is assumed that this must be the Planck size space length required for all the wavelengths combined of all particles in this initial universe. Beyond this pure speculation, the initial size was not a singularity as this must be smaller than this if it exists. (http://www.sciforums.com/threads/size-of-universe-at-big-bang.89848/) – Barnaby Jan 25 '15 at 23:03

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Have a read through Did the Big Bang happen at a point? and the answers to it.

The singularity at the Big Bang is the zero time limit of the equation (the FLRW metric) that describes the expansion of the universe. Most physicists believe that this is a mathematical artefact and does not describe what actually happened. It seems likely that some quantum gravity effect becomes important at the incredibly high energies and densities near the Big Bang, and this prevented the singularity from occurring.

Singularities are common in mathematics. For example the simple function $y = 1/x$ is singular at $x = 0$ because the expression $1/0$ has an undefined value. Since we use mathematics to describe physical systems it's not unusual to find our theories predict singularities under some circumstances. In general the response to this is to believe that the mathematics we've used is an approximation and the predicted singularities would disappear if we used a more accurate mathematical model.

So the answer to your question is that the singularity probably didn't exist.

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John Rennie
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