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It wouldn't cover steganography. What looks like an unencrypted video file may have an encrypted message hidden in the noise.


Also wouldn’t cover encrypted messages sent in the clear. Exchange keys ahead of time and you’re just sending noise to each other. I guess you could still target users sending random noise under the assumption they are using encryption.


Do you think they'd be trying to take encryption away if they weren't already inspecting the packets deeply enough to notice the difference between natural language and encryption noise? One has to imagine that the whole point is to read the underlying message, right?


It's extremely costly to deeply inspect terabytes of traffic.


Assuming the compression is lossless. As it is you have to go looking for places on the web that will even host a bit-for-bit copy of an image you've uploaded. Though I suppose there will always be options.

But if they become too much of a hassle they'll become the domain of people who have something to hide, which would be a significant downgrade.

I myself have nothing to hide, but I want to provide cover in case you do.


It doesn't have to be absolute. Just cross some threshold of inconvenience.


Bhauth wrote an analysis of this idea, and tldr is that trying to get an energy payback on literally vaporizing such a long cylinder of rock is brutally difficult, probably enough to make the economics of the plan unworkable.

https://www.bhauth.com/blog/flawed%20ideas/microwave%20drill...


This is a really interesting perspective but I wish they finished writing the equations out. My attempt at verification didn't match.

Per [1], “[wells] with a regular production casing diameter of 200-250 mm have an average capacity of 5.5 MWe”. Quaise has deep bores that could potentially have higher temperatures, but let's stick with 5 MWe.

At the article's 12 MWh/m³ for drilling, and 250mm bores of depth 10km, WolframAlpha tells me that is 6 GWh.

Divide through, you get 1000 hours or about a month. This doesn't match their “significantly over 10 years” they gave before mentioning waveguide losses.

The main difference I suppose is the thermal conductivity comment, where I didn't follow why Quaise wouldn't be able to use enhanced geothermal approaches. More specifically I think that if a Quaise well has ~1% the energy output of a normal geothermal well, it's pretty weird to frame the problem as about the energy cost of drilling, and not the whole factor-100 reduction in energy output.

To be clear, this seemed like an interesting article and I'm not claiming my napkin math is definitive, I really am neither an expert nor someone who has spent a lot of time investigating this. I do think some more clarity on how the math looks would help their case.

[1] https://www.thinkgeoenergy.com/report-success-of-high-temper...


The article you linked is about conventional geothermal wells, which drill into reservoirs of hot water; they just have hotter water than has been typical. Extracting hot water is not limited by thermal conductivity of rock, but what Quaise plans to do is.

Enhanced geothermal involves fracking. Typical proposals involve creating crack paths between 2 nearby wells by fracking from both. It's been tested some but so far has not been economical.

Apart from the cost issues of enhanced geothermal so far, Quaise plans to drill deeper to higher temperatures to reduce power block costs. Sufficiently hot rock flows a little bit which makes fracking ineffective. Fracking also doesn't work as well with supercritical water. (If not drilling to rock hot enough to flow a little bit under high pressures, it would be much better to use conventional drilling techniques.)


Thanks for the reply!

I'm afraid I'm not really following the argument though. I don't have the technical background to judge how economical EGS is or not, I just want to understand this energy-based argument. I checked to be sure, and Quaise's initial plans (per cofounder Matt Houde) are indeed EGS-based[1], just deeper. It seems correct to me that if they succeeded at building wells that way, they would produce at least comparable energy to standard wells.

It's entirely possible that EGS just doesn't work at really deep depths as you state here, but this seems like a qualitatively different argument to the one presented in the article.

[1] https://youtu.be/yz6rRw59Huw?t=675 "but what we're interested in in Quaise is this novel idea here all the way on the right which we call like to call superhot rock EGS systems"

Actually, they address the energy balance question at the end of that talk.

https://youtu.be/yz6rRw59Huw?t=3016 "[...] we could be using around five megawatts for the drilling process to drill our wells, and let's say we use that five megawatts over a year to drill three holes, so we get an injector and two producers. We predict that configuration of the two producers and an injector at superhot conditions can produce something around 50 to 100 megawatts of electrical energy, again owing to the benefits of producing this superhot, supercritical steam."

They also answer a question on borehole stability, admittedly claiming largely that they don't know.

https://youtu.be/yz6rRw59Huw?t=3254


> It's entirely possible that EGS just doesn't work at really deep depths as you state here, but this seems like a qualitatively different argument to the one presented in the article.

A different argument to the one presented in the article, you say. Huh.

I suppose I can't claim to know more about geothermal than the author of that blog post, but if you check again, you'll find it does mention EGS. Apparently something made the author decide the problems with Quaise using that are non-obvious enough to need explanation.


cf. "but I wish they finished writing the equations out"

The article mentions EGS but, as far as I could tell, only seemed to present it to contrast it with the claim that Quaise is using a worse single-bore strategy.

If I'm just misreading, and it sounds like you're saying I am?, it'd be really helpful to show your working so I can see where the models are differing. There is a factor 100 difference somewhere, it shouldn't be that hard to spot!


This has been amusing and all, but I'm the author of that blog post, and since arguments in a mere comment aren't as reputable I'd updated the post.


Thanks, that makes the position much clearer.

Some questions:

You say, “if there's enough pressure to make a little crack, then the fluid can instantly expand and immediately make a big crack”. My admittedly quite surface level view of the research is that it is viewed as feasible in this regime.

“Close to the brittle-ductile transition conditions of pressure and temperature, new findings suggest that fractures are sufficiently permeable to allow fluid circulation and, in case of insufficient fracture density, enhancement strategies are likely to be successful”

https://www.nature.com/articles/s41467-019-12146-0

I also believe that EGS fracture enhancement marginally prefers hydro-shearing (crack expansion) rather than hydro-fracking (crack formation), so if creating cracks is problematic, that leaves options open.

I also note that to my understanding gas fracking is already a thing, cf. nitrogen fracking. So gaseous behavior doesn't obviously seem like an instant write-off to me.

I'm sure that isn't convincing to you, but it's a bit challenging for me as a layman wrt. geothermal to see why I should trust your gut here, so to speak, and I'm wondering if you have a concrete argument I can evaluate on merits?

For example,

"The hypothesis that the brittle–ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10−16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability–depth relations proposed for the continental crust show no drastic permeability reduction at the BDT."

https://www.nature.com/articles/ngeo2879

I'm definitely not claiming to take these on faith, I'm just saying I haven't really been given a reason to believe those arguments are less trustworthy than your claims otherwise.


It makes it all sound like a problem of engineering, not of physics.

It's really hard to vapourize all that rock and suck it out to the surface with a vacuum. But it's really hard in the sense that the vaporised rock might recondense and stick to the sides of the hole, not in the sense that vaporising the rock costs more energy than you get out of the hole in its 30-year lifetime.


Would it be possible to blow chilled air down the hole that would quickly condense the rock vapor into particulates that don't stick and instead get vacuumed out ?


tldr is that it happened because the universe cooled down from a stupendously insanely high temperature to a merely insanely high temperature shortly after the big bang.

First look at this picture [0]: https://en.wikipedia.org/wiki/Higgs_mechanism#/media/File:Me...

The Higgs field is a complex number Φ (this number can vary at different points in space, we'll come back to this, so don't worry about it for now). You can imagine it as a ball bouncing around on the landscape shown in the image. The higher the altitude of the ball, the more energy it has (just like a ball in real life). Φ = 0 corresponds to the center of the image, the point right at the top of the little hill.

At a high temperature, the ball is jostling and moving around like crazy. You can imagine constantly pelting the ball with marbles from all directions, causing it to dance eratically around the landscape. (Further, the ball doesn't experience any friction. It slows down when it happens to get hit by a marble that's heading in the opposite direction to it.) In reality, there are no marbles, of course, the jostling comes from the interactions of the Higgs field with other fields, all of which are also stupendously insanely hot.

The landscape in the picture has a rotational symmetry. You can rotate it by any angle, and it will still look the same. When the temperature is very high, the ball dances across the whole landscape. It slows down as it climbs up a slope, so it does spend less time at the bits that are at a higher altitude. But if we consider a thin ring around the center that's all at about the same altitude, the ball is equally likely to be anywhere along the ring. The average value of Φ is 0.

As the temperature decreases, the ball's motion calms down, and it spends more and more of its time in the deepest valley of the landscape. It rarely has the energy to climb high up the slopes anymore. Eventually, the ball will start to live on just the narrow ring around the center where the altitude is lowest.

Now we come back to the fact that the Higgs field is a field, which means it has a value at every point in space, and these values can differ from each other. It turns out that all fields in physics "prefer" to have similar values at nearby points in space. There is an energy penalty for fields that change rapidly in space. At high temperature, this didn't matter too much. The Higgs field had lots of energy to pay this penalty, just like it had lots of energy to climb up the slopes of the landscape. So the field here and the field 1nm to the left could have wildly different values. At cold temperatures, it matters a lot. So the Higgs field has the lowest energy if it has the same value everywhere in space. Anything else comes with an energy penalty. If we pick a point in space, and try to move the field clockwise or counterclockwise around the center, the neighbouring points in space pull the field back towards the average of the surrounding values.

So at any point in space, Φ is just equal it its average value, which is not 0. It's not zero because we have to randomly pick a point somewhere along the ring of lowest altitude, which is some distance from the central 0. The universe has randomly selected a direction in this landscape to be "special".

This is the situation from when the universe was insanely hot all the way up until the present. Incidentally, if you vibrate the ball radially, towards and away from the center of the landscape, this vibration corresponds to the Higgs boson.

If we could somehow heat the universe up to a stupendously insanely high temperature again, then the special direction would disappear, and the average of Φ would be 0 again. This is kind of similar to how magnets lose their magnetization if heated past a certain critical temperature, the Curie point. [1] If we let it cool down again, it would choose a different random special direction.

[0] https://en.wikipedia.org/wiki/Higgs_mechanism [1] https://en.wikipedia.org/wiki/Curie_temperature


Very nice explanation! Is it possible that Φ could vary smoothly and subtly over space, such that it's a few degrees or so away from our value in the Andromeda galaxy?


I've always pictured the Big Bang as a big explosion. But maybe it's better to think of it as a big cooling?


Is that so different from an explosion?


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