Did Simon Singh get stumped at the end of his Big Bang lecture?

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At the end of Simon Singh's Big Bang lecture, he was unable to answer a question about why the universe didn't collapse into a black hole as matter came close together. The discussion highlighted that while the density of matter was extremely high shortly after the Big Bang, the universe was rapidly expanding, which prevented it from forming a black hole. Theoretical frameworks, including inflation theory and general relativity, suggest that the dynamics of space-time during this period differ from those of static bodies like black holes. The concept of the Big Bang singularity is distinct from a black hole since it created space rather than existing within it. This question remains a thought-provoking topic in the field of physics.
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At the end of his Big Bang lecture, Simon Singh gets a question from an audience member to which he didn't have the answer. He asked if anyone in the audience (other physicists) had the answer, but no one did.

Here's the question,

"When you go back in time, all matter comes close together, why wasn't it in or why wasn't there a black hole?"

Anyone care to help?

Here's the link, its the Big Bang talk --

http://streamer.perimeterinstitute.ca:81/mediasite/viewer/FrontEnd/Front.aspx?&shouldResize=False
 
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No surprise there. Physics, as we know it, comes to a screeching halt about 1E-43 seconds after the big bang.
 
Hawking originally argued in favor of the idea of a Big Bang singularity, but later rejected it.

Inflation theory suggests something quite different altogether, a sort of high energy density vacuum that decays into a normal vacuum with matter, rapidly expanding.
 
From your answers I'm still not able to understand how the black hole question has been resolved?
 
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This section of the physics FAQ on John Baez's site gives the answer according to general relativity:
Why did the universe not collapse and form a black hole at the beginning?

Sometimes people find it hard to understand why the big bang is not a black hole. After all, the density of matter in the first fraction of a second was much higher than that found in any star, and dense matter is supposed to curve space-time strongly. At sufficient density there must be matter contained within a region smaller than the Schwarzschild radius for its mass. Nevertheless, the big bang manages to avoid being trapped inside a black hole of its own making and paradoxically the space near the singularity is actually flat rather than curving tightly. How can this be?

The short answer is that the big bang gets away with it because it is expanding rapidly near the beginning and the rate of expansion is slowing down. Space can be flat while space-time is not. The curvature can come from the temporal parts of the space-time metric which measures the deceleration of the expansion of the universe. So the total curvature of space-time is related to the density of matter but there is a contribution to curvature from the expansion as well as from any curvature of space. The Schwarzschild solution of the gravitational equations is static and demonstrates the limits placed on a static spherical body before it must collapse to a black hole. The Schwarzschild limit does not apply to rapidly expanding matter.
 
jhe

I would offer the idea that a Black hole is a singularity in space, whereas the Big bang 'singularity' created space and therefore was not embedded in it. In other words, since no space exisited before the big bang (10*-43s) it would be impossible to call the singularity a Black hole. Also, its widely believed that Gravity broke symetry with the Unified 4 fields at 10*-42s, so if there was no Gravity at the point of creation, the definition of a black hole which is intrinsically defined by Gravity's force, clearly could not exist.

Still you ask a very interesting question that cannot foreseeably be known, perhaps the best kind of question to ponder:smile:
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...

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