Nuclear fusion device's first test with hydrogen declared a success

stellerator: harder to build, easier to run (and more efficient)

tokamak: easier to build, harder to run (and less efficient)

Due to the first property, there are more tokamaks around and showing basic functionality for any stellerator is a good/important step.

Edit (relevant quote from the article): """Although there are about a dozen stellarator experiments around the world, including in the U.S., Japan, Australia and Europe, scientists say the Greifswald device is the first to match the performance of tokamaks."""

The number of functional stellarators is rather limited, so getting it built is a success in itself. W7-X will be the largest of the bunch and is supposed to sustain plasma for up to 30min (for comparison, the record for tokamaks is 6.5min, and ITER will only add a minute or two to that).

In magnetic confinement fusion there is a big problem of confinement stability. You are trying to confine a plasma, which is electrically charged and thus an electrical conductor. Electric current generates a magnetic field. This is actually made use of in tokamak designs, which are the most straightforward magnetic confinement systems. However, tokamaks suffer from a fundamental flaw, that plasma current produces a feedback instability loop making it very challenging to attain plasma confinement longer than a few seconds or minutes. That's problematic because the shorter lived the fusion plasma is the more the initial (externally produced) heat as a proportion of the total cumulative heat of the plasma over its lifetime adds up. Short lived plasmas don't spend very long producing fusion heat to "pay back" the energy used to heat up the plasma to fusion conditions to start with.

A stellarator is basically a way to twist the magnetic fields around the fusion plasma tube in such a way so that the trajectories of ions in the plasma will stay inside the confinement volume, without requiring any current in the plasma. This makes the system potentially much more stable but at the cost of a very much more complex arrangement of magnets. The longer the plasma can be confined the longer fusion reactions can be sustained, making it easier to generate more power than was put in to raise the plasma to fusion suitable conditions (high density, high temperature).

The concept is not new, they're just hideously complicated to build. It's a relatively new development that it's possible to model the shape of the magnetic fields and magnets required to keep the plasma. So it's a significant achievement to build one and prove that you can run it while containing the plasma. Yesterdays event is one step on that path.

Yesterday's event was not much about science, but rather about engineering. Building that machine was a gigantic work.

SO yes, they kept it on for less then a second, nothing exploded and future looks quite brigth i would say

The problem with fusion is that they are notoriously hard to achieve, so basically they are always in the brink of fizzling out.

Yes. The reason more humans can live on the planet than the planet could "naturally" sustain, is that they employ outside energy to produce food, shelter, and raw materials.

So more energy, we can support more humans, or existing humans with a higher standard of living.

Three things that you might worry about "go away" with practical fusion energy:

1) Hunger

2) Anthropogenic Global Warming

3) Fresh water supplies

They go away because high energy farming techniques become much more cost effective, fusion power contributes no CO2 and can actually extract CO2 from the atomosphere for commerial use, and the water in the oceans can be desalinated on demand.

It also eliminates many things that cause human suffering, coal mining, oil drilling, fuel transport (oil and coal and gas), smog (electric cars are more cost effective, no more coal fired power plants), and warmth/cooling (if your electricity is cheap enough, everyone can have air conditioning or heat to counteract outside temperatures).

So yes, a practical fusion system will change every aspect of the world.

To clarify: maybe in a more rational, informed society, where we could actually keep building and rebuilding newer generations of fission reactors, then maybe it wouldn't matter as much. We'd have safe reactors and a very small amount of waste products, at a lower residual radiation level.

We don't have any of these things though. In this scenario, then it matters a whole lot. Fusion (I refuse to use the word 'nuclear' here) reactors do not meltdown(nor do the newest fission designs). They generate very little radiation, if any. They have no waste products.

Basically, they remove the "NOT IN MY BACKYARD" variable from the equation. And weaponizing concerns for some countries. And, if they ever work, should generate outstanding amounts of power for their size. Using small amounts of fuel that we don't expect to run out at any non-geologic time scale.

It's easier to sell to the public. "look, it's clean, it's natural, it's just a tiny sun".

So yeah, big deal.

We detached this subthread from https://news.ycombinator.com/item?id=11032716 and marked it off-topic.

They do seem conservative by comparison to their main opponent party, the SPD, which has Marxist roots, but compared to say US politics, they would be considered moderates. In that sense, it's disingenuous to take them out of the German political spectrum (which is much more moderate than the US), and judge them by name alone.

She's certainly not a bible thumping Christian denying global warming. [0]

[0][http://www.environmental-watch.com/profiles/angela-merkel/]

She was there as Head of State, starting an important experiment funded by the state and lending importance to this scientific endeavor in this way. Or at least hoping to garner some positiv press for herself, that she is in dire need of.

But being Head of a (by the way just so called) christian party does not tell anything in a very secularized country like German.