Lots of people could and did design and/or build personal computers in the 70s. Magazines published designs and sold mail order kits pior to the Apple I. There were also a bunch of pre-built home computers contemporary with the Apple I/II, and several of them were more popular.

Neither Steve was really the singular genius people like to retrospectively paint them as. Together they did good work and were in the right place at the right time with the right motivation.

Check out Clive Sinclair - he was an engineer and did pretty damn well selling his computers in the UK.

Kinda, I mean he did well, but it went under. Acorn did somewhat better and parts of Acorn are alive and well to this day.

Furber and Wilson lacked that marketing muscle. Were they a unique talent? I mean... no one else did that. Their CPU worked first time, outperformed their contemporaries, ran at a fraction of the power cost a fraction of the amount and went on to become massively popular.

Maybe Woz couldn't have done that, but it doesn't mean Jobs was the one required to help him, any competenant marketing type could have done the same. Vew few people could have designed the hardware and software that Woz did at the time.

I'd argue that Jobs was unusually good at marketing. Maybe as rare as Woz. I mean, look at the cult of personality that's developed around him where people think Apple (or really Jobs himself) invented all sorts of things which were actually popularized by Apple, but invented by someone else.

His schtick works.

Clive Sinclair's company collapsed within five years of shipping their first computer. Perhaps not a good counter-example.

Which is also mass density. Multiply by c to keep the units straight. (If you're a physicist, you just set c=1, and the units don't matter.)

I guarantee, if you have a mass density of M kg/m3 and you put it in Einstein's field equations, you get gravitation.

What we really need are proper support systems for children in place, but in the real world they often don't exist. Some parents also seem to think they should have full control over their children and know everything they are doing at all times, which makes things like seeking support for being LGBTQ bother difficult for the child and something that the parents demand is not made available.

Maybe we could set up better moderated communities for this kind of thing, but that brings its own problems. As an example, with the current attacks on trans healthcare in the UK, a lot of trans kids are being forced to go the "DIY" route for treatment. It's not illegal as such, but it is something of a grey area. Any kind of official moderation is likely to make such forums useless to a lot of people.

Are you sure you were paying attention when you read it, because that's not what happens in the book. For example, Rocky needs essentially an environmental suit to survive in an atmosphere suitable for humans, due to his planet having much higher pressure and temperature. Communication is established over some time based on engineering principles, which are universal properties of the universe and a classic sci-fi trope for communicating with very different alien species.

I thought it was a pretty good book overall. Lots of interesting ideas and detail. Strong characters, at least for the protagonist and Rocky.

Artemis, about a woman living on the moon. I read it too, it was pretty good.

Wait what?

Are you also dating that love does not in fact transcend the fifth dimension and interstellar was also bullshit?

Come on man.

Jobs gets all the accolades and fame but he was just a pushy sociopath in a suit,

Suit? The guy who famously wore a black turtleneck all the time?

Anyhoo. I think people outside tech overestimate the importance of CEOs and people in tech underestimate it. Without Jobs, Woz probably would have been a really great engineer in some company and you'd never have heard of him at all. He wasn't a product guy, and you need a product not just raw tech to sell. Selling stuff being somewhat important for a company.

Steve Jobs also had a functioning reality distortion field, something not all that many people have and that's really important for building a company...

No, the box is an essential part of the system. In the thought experiment neither the box nor the photon has mass but both possess momentum since the photon can bounce off the walls of the box. The photon and the box, together, form a system that has mass.

You can see how systems can have mass by rearraning the mass-energy equivalence equation to solve for mass:

m = sqrt(E^2 - (pc)^2) / c

The energy and momentum of a fundamental particle are related so you can't manipulate them independently. But if you have more than one particle it's pretty easy to manipulate the momentum of the system without changing the energy, and thus make m non-zero.

Many teachers, including the pop science variety, like to appeal to your intuition. Sometimes that's okay, sometimes it just stunt's your understanding. Your idea of mass is rooted in pre-20th century physics. The end of the 19th and beginning of the 20th century changed how we think about a lot of things, mass included. You're trying to take your idea of mass as an axiom and make everything else fit. It doesn't. Photons are massless. If they weren't, they would either not travel at the speed of light or have infinite energy. The "thing" that gravitates is energy and various types of energy flux, including momentum. That explains, consistently, how photons can travel at the speed of light, massless particles can interact via gravity, and adding energy to a system can increase its mass.

Energy density, yes.

https://en.wikipedia.org/wiki/...

People used to say "relativistic mass." We've realized that was a bad idea.

A fun movie, but the movie wasn't in any way hard science fiction. I don't think there was any real science in it, other than the distances to various stars. It was hand-wavium from beginning to end.

But, heck, that's par for the course for film science fiction. If you try to find the science in "Dune" or "The Last Jedi", good luck.

The Chinese have these kinds of robots deploying much larger installations. They also have drones that fly panels into mountainous areas for installation.

Not that I'm knocking it, it's good that they are copying good ideas. The cheaper solar gets the better, and for political reasons stuff like this has to be home grown.

The UK has a head of state (a king) they've spent a thousand years learning should stand around a look pretty with medals and things but that's about it. The US has a head of state (a president) they've spent at least the last hundred years turning into a cult of personality and giving more and more power to.

France has spent a few hundred years violently oscillating back and forth between the two. They've demonstrated it doesn't really matter whether you call it a king or a president, it's how much power you give them.

The first fission reactor in space, the American SNAP-10A had an experimental ion thruster.

Yes, but it didn't go to Mars. That's why I said we didn't have good ion thrusters. The one on SNAP lasted a whole hour and apparently had quite a few problems even then. Getting the things to last long enough and produce enough thrust to be useful even for station keeping is a fairly recent thing.