This is a rather common misconception about sensitivity, it is only true under the constraint where you are unable to increase the amplitude of your measurement.

You are always limited by shot noise (counting noise, quantisation noise, Poisson noise, whatever name you give it). And people love to say that you can only beat it by squeezing (increase noise in one quadrature to reduce it in another). But another option is to just increase N, turn up the laser power to have more photons or atoms in your sensor and watch your noise floor drop way faster than you will ever get using squeezing.

Now the cold atom sensors are an interesting case. No one has managed to laser cool atoms faster than an overall rate of around 10^9 atoms per second. And we have been stuck there since the mid 2000s. As a result, the fundamental noise limit from shot noise hampers these cold atom accelerometers significantly in short term sensitivity, as they just don’t have enough N of atoms in free fall. In this case, you might look to squeeze to get a better signal, but that’s a lot of complexity for not much gain.

There are only 2 examples I know of where squeezing has made a difference to a real world measurement. LIGO, can’t increase photons without thermally heating the mirrors too much, and confocal microscopes looking at biological samples, cant turn up the laser power without burning the tissue. In 99% of cases, just increase N to make a better sensor.

Here is the paper

https://doi.org/10.48550/arXiv.2608.25563

And here is the easier to read press release from Q-CTRL with less errors and ad block black screens.

https://q-ctrl.com/blog/q-ctrl-achieves-worlds-first-gps-free-quantum-gravimetric-navigation-demonstration-in-maritime-field-trial

They are comparing purely inertial navigation (I assume using the advanced nav boreas D90) and inertial nav combined with gravity map matching.

It is more of a demonstration than a comparison. Pure inertial nav has no way to re zero from an external reference so the error only grows.

Both of these systems are worse than any form of sat nav. But both of them keep working if the sat nav is jammed.

https://doi.org/10.48550/arXiv.2608.25563

Here is the real article without the compounding editorial errors.

https://doi.org/10.48550/arXiv.2608.25563

You don’t. Any appropriately sensitive/accurate accelerometer or magnetometer is sufficient to do this.

The quantum part is 90% hype used to and attract funding. There are some advantages to the cold atom based sensors Q-CTRL makes, along with issues that need to be worked on, but they are other sensing technologies that could beat it in the long run.

There are also MOSFET based bypass panels that can achieve a similar effect at a far cheaper price point. Quite common here in Aus.

The high voltage DC strings are dangerous, but very price + power efficient and our install and wiring rules have made it quite safe.

It turns out to be more of a gang coperation. A decent number of archeological research projects around the Mediterranean are funded by much larger physics grants. They fund the exploration and the anthropologists and other researchers can keep everything, publish the findings etc, as long as the physics project gets all the lead that they find at the bottom of the ocean.

Was about to comment exactly this. Capacitors just can’t store the joules needed in any reasonable amount. There is some conversion loss but lithium batteries usually have a 95% or better cycle efficiency.

If I ever have completed amnesia, the existence of this game would probably be the only silver lining.

I haven’t found anything that comes close to the experience and it is completely impossible to play it again with the same nativity and wonder.

microslop

Haha. We have plenty of moron politicians. But typically all our legislation is usually written by public servants with expert advice and lawyers, and even they get it wrong sometimes. The politicians direct what they want, but most of them have never written a law. I assumed it worked this way in most places.

All good mate, I mostly just try and stop the spread of misinformation on Aus gun laws. Most people don’t know much about them.

The leaver actions are fast. The main difference is that you can leave your finger on the trigger for a pump and are meant to take it off for the leaver action, though you could do it with your non trigger hand. People are also buying left handed bolt action shotguns to get around this, though it’s more awkward. All our shotguns have a capacity limit, usually 5 or less. It looks like these guys modified their barrel mags to hold more.

You’re not wrong about wasted ammo, reliability and reload speed, but you have to think about the worst case scenarios. Situation: close range, large dense crowd, shooter with an unreasonable amount of ammunition, and best luck in the world with no jams or reliability issues. That’s the formula for mass casualties. This is what our laws are effective at protecting against, primarily by limiting the rate of fire.

Can’t believe the guts that must have taken. Absolute legend.

Yeah no shit mate. That’s why pump shotguns are also under a cat C licence here. The legislators weren’t stupid, they basically categorised things on fire rate and public danger.

The Adler lever actions are very questionable in my opinion. They are almost as fast. Though the one I tried would jam all the time. Lever actions like that weren’t a common thing in the 90’s so it slipped by for a while.

And saying that a bolt action is potentially worse than a semi auto is some full on American bulshit. Sure things can jam and go wrong, but in the worst case situation with aresholes like this firing into a dense crowd where aim doesn’t really matter, faster shooting is more casualties.

A cat C license (self loading) is a lot more difficult to get than a cat A,B licence. So far this has worked, no semi auto terrorist attacks since Port Arthur. Thank fuck these guys did not have semi auto weapons.

I honestly wouldn’t have much issue with them removing the cat C licence, effectively banning semi auto outside of military use. But it certainly has some legitimate use cases in feral animal control.

Never heard of this but are they deliberately made to taste bad? Seems like a clever idea. The nicotine is there if you need it but the terrible taste puts you off.

That said, cigarettes smell awful to me and people keep going so I can’t imagine how bad they would have to taste.

It was in the first 5 min that he mentioned it and it’s a clear example of available data that clearly shows a cancer correlation with radiation. I don’t see how this could be a case of people handling it well.

Let’s be very clear. I’m not saying this LNT wrong and I’m also not saying it’s right, but that we don’t have enough info to know one way or the other what the effects are in the low dose case. It’s an area of active research where it is almost impossible to get good data.

There is very clear data showing people do not handle radiation well. Plenty of data from Japan that shows a clear correlation of increased cancer rates with increased radiation exposure rates. This data is statistically significant as there were a lot more people than usual getting cancer.

Getting statistical significant data at lower radiation levels is very hard, as the shot noise goes way up as cancer rate deltas go down to near zero. We just don’t have enough data to know for sure what the correlations are, and no ethical way to get it.

In the case where you are trying to distinguish a shift in cancer rates at the 1 in 1000 level it is statistically insignificant, because your now measuring hit rates in the single digits and trying to distinguish that from other cancer causing factors that are probably at the 1 in 100 level or less (i.e, old people get breast and prostate cancer).

It is about safety limits in the sense that we should not be changing them to solve a PR issue. The accepted principle is ALARA. Governments do allow radiation generating devices and infrastructure usually in that framework. The PR issue is not a result of this safety framework, really it’s more of an education problem. Most people will never understand radiation or statistics well enough to have a good grasp on this. But I think it is getting better. Most people I talk to take issue with the cost of nuclear more than the radiation, especially here in Aus where we have no existing industry. My understanding is even the French are struggling to keep it economically viable, especially when it’s dry.

Energy density should have little to do with cost. We have a lot of empty space, and we really don’t need to capture all that much sunlight even with 20% efficiency. 20% is just fine when photons from the sun are free. The true cost savings with solar is not in the panel cost, it’s that a dozen people with a TAFE degree can build a 500 MW generator in a paddock in 3 months, that operates with minimal maintenance. Nothing can beat this.

Economically viable superconducting links are indeed a long way off but I would bet we see them before commercial fusion. In fact, we already have, they exist in a number of grids, mostly as tests and demonstrations. In east coast Aus, we lose close to 50% of our generated power to transmission lines. You take away transmission loss, and you can build a global grid. Aus can power the EU and NA in their nights with solar. It’s never cloudy everywhere at the same time.