|
Stop the economy! Cut waiting lists! Grow boats!
|
#
¿
Jun 11, 2023 21:59
|
|
|
|
| # ¿ May 13, 2024 17:46 |
|
|
Eh, here's a fun little derail about the shrimp for you... temperature isn't real man! It's a bulk property related to how fast the atoms are moving, and while it behaves sensibly around room temperature +/- a few hundred degrees, poo poo gets weird outside of that, or if the density of matter goes too low or high. Like asking what the temperature of space is when there's hydrogen atoms moving at colossal speeds, but bugger all of them. The closest physical thing is molecular kinetic energy density, but that ignores radiative heat and it's all messy. In solids and liquids, heat is related to sound in that its all vibrations, man, and a supersonic event underwater causes a partial vacuum (the water hasn't had time to move into the empty space yet) which then hits the whole vacuum issues above. So no, you don't really make it as hot as the suns surface, the energy density of the cavity is virtually zero whereas the same volume of the suns surface would technically be 'quite warm'. The imploding sub however, that had the extreme velocity and the mass to count as a super-energy-dense environment, but the energy is a supersonic shockwave driven by the extreme pressure, and compressing air. Which by the velocity arguments is 'superhot' temperature-wise, briefly. Carbon fibre tube lol - you would not get me down that deep, but if I had to design something that did it would be based on a loving sphere.
|
|
#
¿
Jun 29, 2023 12:19
|
|
|
Just to re-rail a derial, many years ago (just before the millenium I think?) we got one of the really early digital set top boxes (OnDigital?), before it got killed off, and we had movies on demand (ish). I forget exactly how we paid, but you then got a message saying the movie would start in x minutes. They basically had a number of digital channels for each movie starting every 15 minutes or so, and when you paid your set got the code to let it tune in to the next one to start. It was a bit shonky but it kind of worked.
|
|
#
¿
Jul 9, 2023 20:14
|
|
|
blunt posted:OnDigital did it too, back in the very early days of digital OTA TV Yeah, was definitely OnDigital. Half the price of Sky (tenner a month I think it was) and you got Sky One, Sky Movies, UK gold stuff.. for about 6 months then channels started dropping off, they changed to ITVdigital or something and sent us little holographic stickers to cover up the OnDigital brand on the box. Classy.
|
|
#
¿
Jul 9, 2023 22:31
|
|
|
Jaeluni Asjil posted:I watched this, it was an amazing animation. Hopefully you can follow this one: Consider a simple 2d orthonormal coordinate system, with the two axis, x and y. And consider the operation of multiplying the vectors together - i.e. dragging one vector along the length of the other to describe an area. Doing it with the x and y axis, we can say that this xy is a unit of area, and it has interesting properties. Like matrices, multiplying vectors in non-commutative - ab = -ba. You can think of ab as pointing out of the paper, either up (+ve) or down (negative). Also, a vector multiplied by itself = 1 (or the length squared, but we're talking unit vectors here anyway). So, what happens if we take our unit of area and multiply ity by itself, we get xyxy. Flip the middle, remebering that ab = -ba and we get: -xxyy And now applying xx = 1, and yy=1, we get -(xy) * (xy) = -1. A geometric unit of area has the same properties as i, the complex number. Turns out, all higher dimensional axis have this property, so i gets defined as the sum of the highest number of dimensions you are using. In 3 dimension, you have scalars (1d), 3 vectors(x,y,z), 3 axis of area(xy,yz,zx), and one axis of volume (xyz) which is 'i' in this space, even tho the axis of area also satisfy the conditions. Also note the neat Fibonacci sequence of numbers - that continues into higher dimensions too. Geometric algebra is fun, and complex numbers may not be as strange as they seem, maybe.
|
|
#
¿
Aug 6, 2023 22:33
|
|
|
Failed Imagineer posted:I was under the impression that quaternions were used in the early days of 3D modelling but had been superseded by *something* more streamlined. But maybe I was misinformed? Still proud of my special Irish -ions They're still used for storing rotations. 4 numbers is smaller than a matrix, and fits neatly in 16 bytes. JA: If you do look into the Geometric Algebra stuff I posted, the result of multiplying 2 arbitrary vectors (a * b) is equal to the dot product plus the cross product - a scalar plus a vector. This is also a quaternion, and represents a rotation about the axis perpendicular to the 'area' it also defines (through the complex axis). You can describe the operation of a quaternion as a rotation via two reflections, one through any plane that contains the 'axis', and then a second rotation through that plane rotated by half the angle. This is one of those things that really needs a diagram - but the point is, a rotation gets described by two reflections separated by half the angle of rotation. Which is why quaternions can describe angles from +/- 360 degrees instead of the usual +/- 180 degrees we expect around an axis, and also the mathematical basis for spin-1/2 behaviour, taking two full rotations to get back to where you started. Imaginary Numbers Are Not Real
|
|
#
¿
Aug 7, 2023 10:52
|
|
|
|
| # ¿ May 13, 2024 17:46 |
|
|
I think the chip thing has been a solved issue for a while now. All the cheap cartridges I buy from Amazon get recognised as genuine by the printer itself now.
|
|
#
¿
Aug 31, 2023 20:08
|
|