- #1

some bloke

- 278

- 96

I replied (this was a while ago) and whilst I'm reviewing it, I am troubled by the fact that this uses such high forces & speeds that I need to start thinking about relativity, which I didn't take into account!

The reply I put up was:

Assuming you go for the smallest diameter, you've got a 5 foot diameter disc which is opening onto liquid hydrogen at 15,000,000°C and 265,000,000,000 Bar.

We can assume that the magical portal is going to have no resistance to go through it, and even if it did, at these pressures it's going to be negligible.

In 1 second, you will have channeled 4,182,768,456 litres of sun into your immediate vicinity. This will form a cylindrical "laser" of immensely high pressure, high temperature hydrogen, which will be 6,032,223,125 feet long. That's 1,142,466.5 miles, or 1,838,621.6km long. If you opened this portal pointing in the right direction, you will have hit the moon after a third of a second.

But then it gets worse.

Every litre of sun you've poured out in this one, monumental lapse in judgement weighs 150kg (330lb). Imagine a 2-litre bottle which weighs as much as a large motorbike. Yeah, you've got billions of them. Assuming that the portal is pointing upwards (to try and vent into space), and that the portal is magically anchored to the planet, then you've just accelerated a mass of 627,415,268,343kg away from earth an average distance of 3,016,111,562 feet. The recoil of this (every action has an equal and opposite reaction) is 576789634843671000000N of force, which is like suddenly dropping 58,796,089,000,000,000,000kg onto the planet, which would probably crack it in half.

But then it gets worse.

Those astute scientific folk out there will have noticed that I'm treating this like it's a solid. It is in fact a liquid, composed of hydrogen at a pressure 265,000,000,000 times greater than the atmosphere at sea level. It's going to expand. In fact, this much hydrogen will form a bubble at a pressure of 1 bar of 265,000,000,000 times larger than in it's compressed state. This makes a bubble which is 3.13x10^22 cubic feet, which is 1% of the volume of the earth, released in 1 second.

But then it gets worse.

Remember when I said that the temperature was 15,000,000°C? I do!

At this pressure and temperature, and suddenly released, it's going to all undergo nuclear fusion. At once. Fusing one kilogram of hydrogen into helium releases

**630 trillion joules**of energy, so fusing just half of what we've got will release 2x10^26 joules of energy. Hiroshima was 1.32x10^13 joules, so you've released 13,175,720,635,206 Hiroshima Bombs somewhere within 60ft. of yourself.

Now, in D&D terms, we can take bludgeoning damage as a baseline. Falling 10ft. deals 1d6, for an average 100kg person (assuming armour) that's about 3000 Joules of energy. So if we divide this by the energy you're releasing, we get an approximation of 6,500,000,000,000,000,000,000d6 damage, for an average of 250,000,000,000,000,000,000,000 damage, or half as much on a successful save.

Dex saves, please?

Now the issue here is that I've said that the plasma is ejected at 1.1 million miles per second, and the speed of light in a vacuum is 186,282 miles per second, so I am curious if someone who knows more about relativity (and presumably fission/fusion) can elaborate further!

So, what else did I need to take into account for this to be as "realistic" as possible (with the inevitable result of the end of the world, obviously)?