@JDługosz and @PavelJanicek There's a lot of it about! I just got a generalist badge too. Nice to know I'm in good company.

@HDE226868 I've edited the answer to remove the Yukawa term, although if the consensus to the meta-post is that more hard-science is better, I might stick it in again at the bottom with a better explanation of what's going on. I really don't mind getting rid of it (so long as it improves the answer), it's just that I like maths in answers, so having such a mathematically-based answer without any actual maths just looks weird to me. I really don't want to put people off though!

(As you asked, f' in this sum are right-handed leptons, so are spinors (adding the bar makes them anti-right-handed leptons). f are left-handed leptons, so are also spinors. phi are the 2 Higgs scalar fields (phi_0, phi_1) and the circle is a kind of product: f \circle phi = f_0 phi_1 - f_1 phi_0, so you're summing over the 3 generations of leptons)

@Mithrandir24601 Cool. I'm fine with whatever you end up doing.

@Mithrandir24601 Okay, I mostly guessed correctly, save the product, which seems reminiscent of a cross product.

@HDE226868 Yeah, another way of writing that bit is f_i phi_j levi-cevita^{ij}

Oh, I've seen that before in passing.

Right, that makes sense.

I have a vague thought about designing a game that works from the engine up as a physical simulation. So for example a fire attack doesn't do x damage. Instead anything within the range of it gets an increase in temperature, and then those things respond however makes sense for that increased temperature.

@DubberRucky That would be so, so much better

And make everything very object based, so that it all works work on physical input -> black box -> physical output. Which I think gives scope for multi-threading well?

Am I envisioning a do-able thing, or is this going to overtax any system?

What exactly do you mean by physical output - do you mean an actual thing happens in the real world (vibration of a controller or whatever) or do you mean that the simulated objects are black boxes, which react realistically when something is done to them in-game?

In game

So for example, electrify water -> black box -> water applies electricity to objects in contact with it

Then it's not just that it 'gives scope' to multithreading, but probably won't work without it

And yes, it's doable - I once (a few years back) was at a short talk by a games graphics designer and he talked about realistically simulating water, which required the parallel processing capabilities of a graphics card. Mind, this was a few years ago, so I might not be remembering it very well

I'm suspecting the issue in trying to implement may be that for any given frame I have to handle nearly endless race conditions? In that it won't reflect reality if action A should causally affect B, but the inverse happens. Or worse some kind of infinite loop of input/output not possible in reality.

That sounds vaguely like the general issues that parallel processing faces - you have to ensure that each thread is working with the right data (I might be reading what you've written wrongly though)

One issue is that the more realistic you want it, the more processing you have to do, so the longer it takes - if you want to simulate a car crash for a car manufacturer, you're able to give the simulation a day or two to figure out what happens over the course of a few seconds and so can be really accurate, while in a game, the same car crash has to be simulated real-time, so will be nowhere near as accurate

Yeah it's going to need a lot of shortcutting

And probably a lot of memory because each object has to store a lot of state info

Probably. That probably why modern graphics cards have so much memory

lol

mostly used for textures

But I don't do any of this stuff, so I don't actually know what I'm talking about...

though nvidia does have a full physics engine they run off the GPU

@JourneymanGeek Well, that's my new thing learned for today!

@Mithrandir24601 phy-x

they've had it for years. Original version could run on a CPU too

If you play borderlands 2 on a PC with the effects turned up, that's what it uses for stuff like water

Also in things like the Witcher 3

PhysX

that thing ;p

So if I'm getting what the internet is saying right, the graphics card is important for rendering water, but useless in simulating it?

usually

did I just miss a computing discussion?

cpu is for consecutive operations > scheduling, processing, stuff like that

@dot_Sp0T Yeah, though it wasn't a long discussion

gpu is for parallel operarions > calculus, graphics processing, simulation

hey there @Mithrandir24601 and @dot_Sp0T

Rytsas @Shalvenay

@Mithrandir24601 how're things going?

@Shalvenay Same old, same old... Had a decent day, but didn't exactly do very much apart from some shopping

You?

ran some quick errands. also, pondering the physical properties of mithril (other than being as strong as steel, but lighter, which makes me think it'd be somewhat similar to titanium)

@Shalvenay Hmm... Makes sense to me (who knows nothing about materials). I like the idea!

@Mithrandir24601 the main problem with seeing the two as equivalent is that you cannot smelt titanium ore

you wind up with titanium carbide if you try to do with rutile what you do with hematite

How do you turn rock-titanium (or whatever's mined) into actual usable strong-titanium then?

you either need a big chlorine tank to go TiO2 -> TiCl4 which then can be turned into titanium

or you need electrochemical processing

OK. [nods as if I understand exactly what's going on. Even though I haven't got a clue]

So, essentially, you start off with non-good titanium, then do chemistry and get usable titanium out?

yeah

I really should have done a module in chemistry at some point in A-level/Uni...

it's called the 'Kroll process'

(you can directly reduce the oxide to the metal,but you need something like metallic sodium for that)

Still don't really understand what's going on, but the Wiki looks interesting

in any case, it's not something that anyone in Middle-Earth would have ever figured out

"Titanium is about six times as expensive as stainless steel". That's a lot cheaper than I was expecting

not even Gandalf himself

just for lack of the appropriate reagents

Well, the dwarves were pretty advanced, but you do have a point

(when it comes to metalworking at least)

it's clearly not aluminum (although that'd be even harder to produce in the Shire, I dare say)

Even I know that aluminium is softer than steel :P

[until some materials person comes along and tells me that what I've just said is completely wrong]

" Forging mithril was a secret of the ..? dwarves? .. "

They probably had huge chlorine smelt chambers

They may have some chemical processes that seem advanced for their day. Ancient Colombians could forge platinum even though they couldn't melt it.

Mined by dwarves in Khazad-Dum, so seems about right

@Mithrandir24601 Interestingly while aluminium is less hard than steel, there are some very hard composites, It should also be noted that the aluminium oxide layer that forms on aluminium is actually very very very hard,.

@DubberRucky I am learning many thing today!

@DubberRucky makes me wonder how they made all that chlorine then

@Shalvenay Nicked it from swimming pools.

@Bellerophon LOL :P

god knows, something the heated with it that emitted chlorine

there are chlorine based gemstones, maybe they crushed those

it is possible to use aluminum as a reducing agent to make titanium at least...

but that doesn't help you much, since you need either electrolysis or an alkali metal to produce aluminum

one possibility for getting chlorine gas would be to use muriatic acid mixed with ground pyrolusite

at least Gandalf would be able to find the raw materials for that one...