Death's End - The Dark Forest Attack on the Solar System

Towards the end of Cixin Liu's Death's End, someone in a planet far, far, away sees that the Trisolarian system was destroyed, and works out that our Solar system probably did it. This person is about as low in the organisation as anyone can get without actually being a cleaner. He goes to his boss to ask for the relevant weapon, and having been authorised, flips it carelessly in the direction of our Sun. It's a small two-dimensional thing, and is observed with curiosity as it makes its way towards us. Then it is activated, and... squish squash squwash... the space around it loses the third dimension. Everything is crushed down to two dimensions and destroyed in the process. The effect expands outwards at light speed, and nothing can stop it. We now understand the episode where our heroes encountered a four-dimensional world that seemed to be shrinking to three-dimensions. Our solar system, and in fact ultimately the whole universe, is going to be rendered two-dimensional. Which, as one of the characters says, is only not a problem for the aggressor, if they are actually two-dimensional in the first place.

This kept coming back to me. Such Dark Forest attacks, we have earlier had suggested, would only happen when the cost and risks of doing so were minimal and did not give away the attackers location away. Which is exactly what happens. The casual destruction by a lowly employee. The fact that destroying a solar system and then a galaxy is not something anyone needs to debate or get clearance for. The sheer off-handedness of it all.

Before you worry, the physics of the device - along with most of the physics in the series - is utter nonsense, but we go along with it because the story it enables is so interesting.

After a week of this sticking in my mind (I really am not that preceptive) I got what Cixin was up to. It's an analogy with the legal bureaucracy. Where public employees can reach out and destroy careers, marriages, and lives with a charge here, an investigation there, a court case, and the sentence, tossed as it were at the offender with a flip of the wrist. They only penalise what comes to their attention, investigate as little as possible, spend as little effort as possible running the process, and hand out the penalty with no thought for its effects or consequences.

I suspect it may be possible to read a lot of the book like that. In fact, there's a passage in it where he tells us that's what he's doing. But I'll leave that for you. And I could be reading far too much into it.

The Fermi Paradox - A Boring Answer

The Fermi Paradox is the difference between the supposed number of planets supporting intelligent life that there should be in the vastness of the Milky Way, never mind the Universe, and the fact that we haven't picked up any radio-signals from any of them, let alone slapped a parking ticket on a visiting space-craft. Whenever anyone gets bored, they form a theory on why we have the Fermi Paradox.

The doozy is the Dark Forest Hypothesis, exploited by Cixin Liu in his Three-Body Problem trilogy, appearing so I gather on a Netflix near you. This is the idea that the universe is actually stuffed full of advanced civilisations, and they are all keeping quiet so that they aren't attacked by another one, rather like an animal moving through a forest at night, which keeps as quiet as possible to avoid giving its presence away to the predators all around it.

At the other extreme is the Uniqueness of Us hypothesis, which is that there's only us in the Universe, because making a planet that can support intelligent life and Kier Starmer is 0.000000000000000000000000000000001% possible. And that may be too high.

Then there's the We Got Here First hypothesis, which holds that we are the first civilisation advanced enough to support Angela Rayner, and all the others have just about reached Plato, or are currently building Stonehenge, or maybe are still single-cell organisms. Just think, in another million years, they too will be have their very own Rachel Reeves.

And of course, there's the Smartypants theory, which is that we have been visited by aliens, and they found us so stupid and crude, they flew off and give us a 1-star review on TripAdvisor. Or they found us too aggressive. Or they thought they would come back when Wes Streeting was not in charge of anything.

However, the boring answer is this....

Radio, television and radar broadcasts use electromagnetic waves, and electromagnetism is, as we know, magic + Maxwell's Equations. How these waves travel depends on the medium and the wavelength. Very short waves (1-10 mm) are absorbed by the atmosphere in a few kilometres. Very long waves (1-100 km) bounce between the earth and the ionosphere and can flow over hills and down valleys. Radio, television, mobile phones and radar use waves between 10cm and 100m, and these mostly travel in straight lines. The transmitters are designed to direct the waves to where the audience is, not spray it all over the place where the audience isn't, like outer space. Some of it leaks, but not a lot.

Here's the calculation. Whatever the aliens were using to listen, our signals would need to be audible above the white noise of the Universe, the Cosmic Microwave Background (CMB) radiation, that covers the radio, TV, radar and mobile phone frequencies. At those frequencies, the CMB has a power of on the order of magnitude of 10^(-7) Watts / sq metre. For a station broadcasting at 5,000 kW / sq m (which would be a lot) and an inverse-square fall-off, since 1 light-year is about 9.5 x 10^15 metres, that's a fall-off of 53dB, so our station's signal would have a strength of about 5.5x10^(-10) Watts/sq m, which is about 4dB below the CMB. To get 5dB above the CMB, we would need to have 1,024 transmitters of that strength going flat-out. All of them so badly designed that they sprayed energy in all directions equally.

At 10 light-year's distance, signal loses around another 20dB, and there aren't enough transmitters on earth to get the total above the CMB.

The nearest candidate planets are 4.22 light-years away, and the next is 11 light-years. And those aren't good candidates.

Nobody ain't hearing nothing.

2025. Let's Be Careful Out There

It's going to be a good year if you're a train driver or a civil servant, or some hack pushing AI, or anyone selling arms and ammunition to anyone else, or in the business of selling emergency supplies of energy, or building those money pits HS2 and the Hinkley Nuclear station, or if you're a lawyer on the endless Covid enquiry whose conclusions we all thought we knew but will have been changing with the times, or if you are providing hotel accommodation for illegal immigrants, or if you're a human rights lawyer being paid by millionaire activists to prevent the expulsion of foreign criminals, or if .... oh heck, you get the picture.

Here's a financial goal for 2025. Try not to end the year with more debt that you started it.

And A Prosperous 2025 To You

In-Between Days Bob Fosse Number

Happy Christmas

Stoicism Sucks - Caught Up

This from Art Chad...



Because I have long felt that Stoicism is about the last thing anyone should be following. It's taking life advice from Elon Musk or Francois Arnault. No. Just. No.