What force is created before supernova explosion?

[Hornbein]

Right. That mechanism says that if there is net heat loss, gravity will slightly exceed pressure. It is a misconception to say that the heat loss ever causes temperature drop, however-- the temperature can rise monotonically everywhere, throughout the process. The key is that the slight excess of gravity is always causing contraction, allowing gravity to do work that pumps kinetic energy into the system-- usually at a rate twice as large as the net heat loss that is driving the whole business. Thus the excess kinetic energy piles up and causes the continuing temperature rise, but even though the temperature is steadily rising, the rising gravity continues to slightly exceed the pressure.

Anything that short-circuits the net heat loss will stop this process, and either fusion or degeneracy can do that-- fusion by replacing lost heat, degeneracy by preventing heat loss in the first place.

...

(It [EDM] also inhibits internal collisions, so it conducts heat very efficiently, but that just redistributes excess heat, most of the internal kinetic energy is still insulated against any heat loss.)

So, how does EDM prevent heat loss if it is a thermal conductor?

 

[willem2]

That is more like three Suns.

Venus insolation is "only" 190% of Earth's.

Having 3x insolation for weeks would cause air temperature to quickly rise well above 100 Celsius.

Looks sterilizing to me.

I agree that it would kill off most of the humans. A tripling of the incoming radiation would mean a rise in the absolute tempererature of the 4th root of 3, so 288k * 1.316 = 379K, so about 106C. This is of course a calculation only based on the Stefan-Boltzman radiation law, and ignores such things as water vapour/cloud formation, wind patterns etc. Three weeks of 3 times solar radiation is however less than what the sun does to warm the oceans in a summer, so the oceans should warm less than 10 degrees C from this. You might survive if you live near the ocean.
Moreover, you'd survive near one of the poles, and likely a large part of the northern or southern hemisphere wouldn't get much extra radiation.
Where I live at 53 N, december insolation is only about 13% of summer insolation. If the sun became 3 times as bright, for a few weeks in winter, that would be no problem at all.

 

[nikkkom]

I agree that it would kill off most of the humans. A tripling of the incoming radiation would mean a rise in the absolute tempererature of the 4th root of 3, so 288k * 1.316 = 379K, so about 106C.

Venus is only x1.9, yet its surface temp is in excess of 450 C!

Evidently, your model is grossly oversimplified.

 

[willem2]

Venus is only x1.9, yet its surface temp is in excess of 450 C!

Evidently, your model is grossly oversimplified.

But Venus didn't get like that in a few weeks.

You have a maximum of 700 W/m^2 extra coming in. (no clouds, no reflection, ignoring the extra outgoing radiation as the surface heats up).
In a month this is 4.34 * 10^10 J/m^2. Enough to evaporate 20 meters of water, or heat 100 meters of water by 45 degrees or a combination of both, but not nearly enough to sterilize the earth, and a part of the Earth will escape, no matter where the supernova is.

 

[newjerseyrunner]

Gamma Ray Bursts occur in the early formation of a galaxy (nature of the beast). The Milky Way has long ago past the point where our galaxy will host such an event.

Not true, gamma ray burst come from the collapse of supermassive stars.

When a huge star's core collapses, it creates a black hole in the middle of it. When that happens, the inside of the star quickly starts hollowing out as the black hole swallows it from the inside. The intense gravity creates an accretion disc inside the star and near the event horizon particles are accelerated to nearly the speed of light in a column perpendicular to the spinning disc. Those jets are the gamma ray burst.

WR 104 is a potential gamma ray burst waiting to happen, and it's also pointed right at us.

 

[Ken G]

So, how does EDM prevent heat loss if it is a thermal conductor?

It is a perfect conductor with no heat to lose, like a superconductor at absolute zero. Exactly like that, in the limit of complete degeneracy.