I like to keep an eye on my network exposure.

The question "who is responsible for accidents" here is no different from a thousand other "who is responsible" judgements. Unless you have some reason to think that a repaired John Deere tractor is more likely to cause accidents than a non-repaired one, this is just a distraction.

We have a legal system that addresses questions of who is responsible. If you don't like the way these decisions are made, you need to fix the legal system, because changing right-to-repair laws won't do beans to solve that problem.

The multi-km range seems a stretch, but quantum magnetometers based on Nitrogen-Vacancy defects in diamond is a real technology.

https://www.photonics.com/Arti...
  https://www.ll.mit.edu/r-d/pro...
  https://www.nist.gov/programs-...
  https://academic.oup.com/nsr/a...
  https://pubs.aip.org/aip/apl/a...

Still, Slashdot doesn't have to play along with their weasel wording. For example, "ergonomic collars that deliver an electric pulse" - just say "shock collar". Don't help them whitewash what they're talking about.

Looks interesting, I'll take a look when I get back in to work.

Probably the metadata is in UTC, and they forgot to convert it for Americans.

Interesting. I've never seen this claim made before; do you have a reference?

I'm saying this because mass is part of the source term of the Einstein field equations. Are you being deliberately obtuse because you want to extend this meaningless conversation infinitely long despite the lack of any content here?

Huh? No, rho/c is just one term of the tensor. If you want it in some other frame, you can't just take one term out of a tensor, you have to use the full tensor.

If you label the T00 term energy density, it's not invariant either. One term out of a tensor is not invariant no matter what you label you put on it.

Correct. The stress-energy tensor is the fundamental source for gravity. Which mass is a part of.

Correct. And you plug it in as the 00 term in the stress energy tensor.

I don't know what you think those quotes means, but I don't think either one is denying the existence of mass, nor saying that mass is not a source of gravity.

I'm not sure how much clearer I can be. Mass is explicitly part of the source term for Einstein's field equations.

If the point you are trying to make is that it is not the only thing in the source term, well, yes of course. The statement I was disagreeing with was "There is no mass term in the stress-energy tensor, nor anywhere else in the Einstein Field Equation." This is absolutely and unambiguously wrong.

You're confusing the importance of avoiding Kessler syndrome in LEO with the difficulty of causing Kessler syndrome. GEO debris can potentially remain there for millions of years before interactions between the gravitational pull of the Sun, Earth, and Moon sufficiently perturb it. LEO debris remains for weeks to months. You have to have many orders of magnitude more debris in LEO to trigger Kessler Syndrome, where the rate of collisions exceeds the rate of debris loss.

The fact that a LEO Kessler Syndrome would also be short is something that exists on top of that.

It's also worth nothing that not only are modern satellites not only vastly better at properly disposing of themselves than they were in the 1970s when Kessler Syndrome was proposed, but they're also vastly better at avoiding debris strikes. All of these factors are multiplicative together.

Lol, I was thinking of this instead ;)

People forget that the primary concerns about Kessler Syndrome were about geosynchronous orbit, which used to be where all the most important satellites went (many of course still go there, but not the megaconstellations). It takes a long, long time for debris to leave GEO. But LEO is a very different beast.

They said it's internal rather than a collision, so probably a failed COPV would be my guess.

Yeah. In particular:

with fragments likely to fall to Earth over the next few weeks

LEO FTW. Kessler Syndrome is primarily a risk if you put too much stuff with too poor of an end-of-life disposal rate in GEO. End-of-life without proper disposal rates have declined exponentially since Kessler Syndrome was first proposed (manufacturers both understand the importance more, and do a better job, of decreasing the rate of failures before deorbit - in the past, sometimes there wasn't even attempts to dispose of a craft at end-of-life). And now we're increasingly putting stuff in LEO, where debris falls out of orbit relatively quickly. It's not impossible in LEO, esp. with higher LEO orbits - but it's much more difficult.

Or to put it another way: fragments can't build up to hit other things if they're gone after just a couple weeks.

And this trend is likely to continue - a lower percentage of premature failures, and decreasing altitudes / reentry times. Concerning ever-decreasing altitudes, we've already been doing this via use of ion engines to provide more reboost (with mission lifespans designed for only several years before running out of propellant, instead of decades like the giant GEO ones), but there's an increasing interest in "sky skimming" satellites that function in a way somewhat reminiscent of a ramjet - instead of krypton or xenon as the propellant for an ion engine, the sparse atmospheric air itself is the propellant, so the craft can in effect fly indefinitely until it fails, wherein it quite rapidly enters the denser atmosphere and burns up.

ED: "But it doesn't work for gravity with linear curvature"