A starkiller, theoretically possible? (Star Trek: Generations)

[Tisthammerw]

I watched Star Trek: Generations and wondered if it was actually theoretically possible to "blow up" a star in that manner.

What happens is that the torpedo launched into a sun stops all nuclear fusion, which results in a “quantum implosion.” This in turn creates an immense shockwave which is powerful enough to pulverize a planet.

Is such a device theoretically possible? And if the nuclear fusion were halted, would such a shockwave be created?

 

[kirovman]

If outward radiation pressure from fusion were somehow halted, the star would collapse in on itself from gravitational forces, I think.

Things like Quantum Implosion though, it's just pseudoscience.

 

[Tisthammerw]

If outward radiation pressure from fusion were somehow halted, the star would collapse in on itself from gravitational forces, I think.

I suspected so as well. Still, what about the shockwave?

 

[Helvete]

If a white dwarf gets close enough doesn't it "suck" the matter from the star? please correct me if I am wrong, but that's the closest thing i can think of.

 

[Orion1]

Stellar Shutdown...



For stars greater than 2 solar masses, It is possible to halt all nuclear reactions in a star by adding a Chandrasekhar-sized mass [tex]1.4 M_{\odot}[/tex] of iron or cobalt directly into the stellar core.

The result of this would be a supernova.

As for stars with one solar mass, perhaps around [tex].437 M_{\odot}[/tex]

Reference:
http://courses.physics.kth.se/5A1381/reports/kretov.pdf

 

[franznietzsche]

If outward radiation pressure from fusion were somehow halted, the star would collapse in on itself from gravitational forces, I think.

Things like Quantum Implosion though, it's just pseudoscience.

Not, not necessarily. Hydrostatic equilibrium is dependent on the pressure gradient, meaning how quickly the pressure changes as one moves from the center to the surface.

Quantum Implosion? UH, no.


Th logistic of putting as little as .437 solar masses of any kind of matter are ridiculous. all the planets combined would fall short if I'm not mistaken.

 

[Tisthammerw]

Not, not necessarily. Hydrostatic equilibrium is dependent on the pressure gradient, meaning how quickly the pressure changes as one moves from the center to the surface.

Quantum Implosion? UH, no.


Th logistic of putting as little as .437 solar masses of any kind of matter are ridiculous. all the planets combined would fall short if I'm not mistaken.

Yeah, I think you're right. The sun's mass and size is tremendously large compared to even the largest of planets in our solar system. But what about the shockwave? If the nuclear fusion were somehow stopped, would there be an implosion and a phenomenal shockwave capable of pulverizing all planets within the system?

 

[Orion1]

Stellar Shutdown...

If the nuclear fusion were somehow stopped, would there be an implosion and a phenomenal shockwave capable of pulverizing all planets within the system?

Solar sized stars do not nova, shutting down the core would perhaps only result in a brown dwarf star.

 

[Tisthammerw]

Solar sized stars do not nova, shutting down the core would perhaps only result in a brown dwarf star.

You mean supernova, don't you? IIRC our star is destined sometime in the distant future to go nova and become a red giant.

 

[Orion1]

You mean supernova, don't you?

IIRC our star is destined sometime in the distant future to go nova and become a red giant.

Yes, supernova.

This is true, however if the core is 'shut down', it will not produce a 'red giant'. Red Giants are driven by radiation pressure within the core from 'burning' much heavier elements than hydrogen.

 

[Manchot]

Stargate SG-1 has also had an episode where a star was blown up, and I guess that it could technically be possible. Basically, they opened a wormhole to a Stargate near the event horizon of a black hole, and threw the other end into the star. Though its description was fleety, it was rationalized by the fact that the dynamics of a star are such that the outward pressure of the fusion was counterbalanced by the inward pressure of gravity. By removing some of that gravity (presumably by sucking away helium), the star exploded.

 

[Orion1]

I suppose that a stellar core shutdown would result in an explosion from the gravitational collapse rebounding from the core, some type of nova that is non-evolutionary resulting in a brown dwarf.

If I understand my sci-fi Trekkie Trivia, what was described was a substance called 'Tri-Lithium', which is a 'quantum phase inhibitor' palm-sized crystal. How any crystalline substance could survive a journey into a 15-20 Mega-Kelvin stellar core without disintegrating is beyond my known science. Also, consider the fact that the same palm-sized object of solid Neutronium, still could not accomplish stellar shutdown.

 

[Tisthammerw]

I suppose that a stellar core shutdown would result in an explosion from the gravitational collapse rebounding from the core, some type of nova that is non-evolutionary resulting in a brown dwarf.

Fascinating. Would the resulting explosion be enough to pulverize the planets in the system? (I suspect yes because of the star's tremendous mass, but I am uncertain.)

If I understand my sci-fi Trekkie Trivia, what was described was a substance called 'Tri-Lithium', which is a 'quantum phase inhibitor' palm-sized crystal. How any crystalline substance could survive a journey into a 15-20 Mega-Kelvin stellar core without disintegrating is beyond my known science.

That could be explained away by really powerful heat shields. Though of course such shields are well beyond known technology.

Also, consider the fact that the same palm-sized object of solid Neutronium, still could not accomplish stellar shutdown.

Hmm, neutronium is pretty dense stuff. What size would the neutronium have to be? And what about a miniature black hole? Could that result in a chain reaction (eventually sucking up enough matter) to achieve stellar shutdown?

 

[franznietzsche]

if fusion just simply stopped the star would neither collapse nor explode, it would just become a cool collection of gas. However, it is not physically possible to ahve a collection of hydrogen gas that big and not have fusion. Well, that's not perfectly accurate, but in the case of the sun it is. Without blowing off large outer layers, you could not stop the fusion reaction. and explosion could stop the fusion by realising thermal energy and decreasing internal pressure. THink of it this way: to cause the star to explode would require a massive burst of energy, stopping fusion takes away energy, it does not provide it.


when you say miniature black hole you need to be more specific. What exactly is "miniature"? A quantum black hole through hawking radiation would release tremendous amounts of energy, potentially at a higher rate that its surface area(of the event horizon) could let mass in. A final evaporation of a quantum black hole placed in the center of the sun could "possibly" (i use quotes because while it seems logical, that does not make it possible) release enough energy to blow the sun apart.

 

[Tisthammerw]

when you say miniature black hole you need to be more specific. What exactly is "miniature"?

Small, perhaps the size of a baseball. I hypothesized it would suck enough matter to become even more dense, starting off a chain reaction etc.

 

[franznietzsche]

Small, perhaps the size of a baseball. I hypothesized it would suck enough matter to become even more dense, starting off a chain reaction etc.

Give that

[tex] v_e = \sqrt{ \frac{2GM}{r} } [/tex]

A baseball is about five inches across (not sure exactly, and i don't happen to have one ready). so that means r = .0625 m.

Setting [tex]v_e[/tex] to c, and solving for M we get:

[tex] M = 4.21664x10^25 kg[/tex]

By comparison the Earth is only [tex]6x10^24[/tex] kg

So
1) This is not a small black hole. Sure, its not a super-massive (not even massive really), but its not even close to a quantum black hole.

black holes with masses less than about 10^11 kg (the mass of a small mountain) can evaporate in less than the age of the Universe. The Hawking temperature of such mini black holes is high: a 10^11 kg black hole has a temperature of about 10^12 Kelvin, equivalent to the rest mass energy of a proton. The gravitational pull of such a mini black hole would be about 1 g at a distance of 1 meter.

A baseball sized one would be more than 10^13 times larger, and so would release energy more slowly. What would likely happen in either case is that the black hole would simply consume the sun. Such an event would have no real gravitational affect on the planets (at the same distance from the center of the black hole the gravity is the same as that distance from the same mass star.) Of course the lack of the big bright ball in the sky would not be good for us.