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Popular discussions referencing John Wheeler’s thought experiments, which suggest that sufficient energy confined in a small region could form a black hole. My confusion is about why pressure-driven compression in thermonuclear weapons cannot satisfy this condition, despite achieving very high densities briefly. John Wheeler mentioned that if we were to take all the heavy water from our ocean and creates a hydrogen bomb out of it, it could hypothetically create a black hole, but shouldn't the gravitational force be more than the compression caused due to the bomb/instrument?

Will it reach the Schwarzschild radius required for a black hole?

Even if it does reach am sure that the Hawking radiation will result it in evaporating instantaneously, but I just want to know if it's possible through it

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    $\begingroup$ Hi Shaun Baiju. Welcome to Phys.SE. Did you try to do a back-of-an-envelope-calculation of the radius of the black hole created by the bomb? $\endgroup$ Commented yesterday
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    $\begingroup$ if we were to take all the heavy water from our universe... Surely this is a good enough reason why we can't do this. $\endgroup$ Commented yesterday
  • $\begingroup$ @Qmechanic Yeah, tried that it makes sense now. Thank you! $\endgroup$ Commented 22 hours ago

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The density in the pit of an exploding nuclear weapon is not especially high. The trigger only has to compress the core to greater than the critical density so even only a 50% density increase is sufficient. Carey Sublette's nuclear weapon design site says:

The convergent shock wave of an implosion can compress solid uranium or plutonium by a factor of 2 to 3.

If we take a 100kg mass the density required to form a black hole is of the order of $10^{75}~\text{kg/m}^3$, which is many, many orders of magnitude greater than the density of plutonium or uranium. The bottom line is that the density required is so many orders of magnitude greater than anything achieved in a nuclear bomb that it is beyond any conceivable human technology.

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  • $\begingroup$ I tried the back-of-an-envelope-calculation with a couple approximations, and the conclusion aligns with your answer. Thank you for your time in answering my question. $\endgroup$ Commented 22 hours ago
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    $\begingroup$ You left off a few "manys". $\endgroup$ Commented 17 hours ago
  • $\begingroup$ @LeeMosher :-) ${}{}{}$ $\endgroup$ Commented 17 hours ago
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Simple counterargument: The sun is basically a continuously-exploding hydrogen bomb, and it still can't create a black hole.

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    $\begingroup$ Plain hydrogen fusion isn't like deuterium or deuterium-tritium fusion. The fusion reaction inside the Sun runs very slowly, it's not like a bomb. The power density in the Sun's core per unit volume is comparable to that of a compost heap. Per unit mass it's even worse. See physics.stackexchange.com/q/370899/123208 & physics.stackexchange.com/a/540199/123208 $\endgroup$ Commented 7 hours ago
  • $\begingroup$ The pressure in the core is still extremely high, though. $\endgroup$ Commented 6 hours ago
  • $\begingroup$ That's true, and so is the density. But that's mostly due to the gravity rather than the fusion. And it's tiny compared to the density needed to achieve a black hole for even a solar mass. The density needed for a smaller mass is much greater. $\endgroup$ Commented 6 hours ago
  • $\begingroup$ Blackhole requires sufficient mass which our Star(Sun) does not have(Not enough Gravitational pull), even if it's fusion stops ie. it runs out of fuel which will cause it to be a white dwarf. (Lowkey wanted to add mass to the sun at first but then realized if we do achieve such technologies we might as well make our own star and force it to collapse rather than bullying the sun) $\endgroup$ Commented 4 hours ago

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