Why don't we see aliens? Is there really no one in the Universe except us? The farm paradox, although not really a paradox, has acquired many possible explanations over the years, from a great filter and unique land to a dark forest and a zoo. Some explanations seem quite plausible, others are frankly weak. But today I want to share one more explanation. What if the entire galaxy is connected by a global interstellar internet? What if huge amounts of information are constantly flying between the stars , but we can’t see it? Why? Because we are not connected yet. Jokes aside, this is a serious topic. Now I'll tell you. Hello. To be honest, at first this idea seemed pretty crazy to me. But the more I read about this concept, the more it seemed to me that there was something to it. No, I'm not saying that such a network exists now, but it could be created in the future, and it could become one of the most important mega-projects in the entire galaxy. So, what's the point? I'll start with Nikolai Kardashov. No, of course not. Back in 1959, physicists Giuseppe Caconi and Philip Morrison demonstrated that even at the then-current level of radio astronomy, it was possible to send and receive radio signals over interstellar distances. In 1960, Frank Drake launched the OZM project. The 25-metre radio telescope at Greenbank searched for artificial radio signals from the Sun-like stars Tau Ceti and Isilon Iridanus. But Kardashov, in his article from 1964 on the transmission of information to extraterrestrial civilizations, quite succinctly explained which cosmic radio signals could be artificial and why. So, first of all, what signals we're looking for depends on what civilization is sending them. This is where the famous Kardashov scale types come in . If a civilization already operates with energy of about 10 to 12 watts, then it has reached type one of this scale. If 1026 W of energy is available to her, then it is already type 2, and 1037 is type 3. Subsequently, the energy boundary of the first type grew significantly, since it was decided to link it with the total energy received by our planet from the sun, that is, 10 per set. The second and third boundaries were not significantly revised. Type has mastered all the energy emitted by the sun, and type three has mastered the entire galaxy. That's about 100 billion suns. All three types can exchange interstellar messages, but their capabilities are different. Type one is highly energy limited. It can only transmit highly focused signals, most likely on limited frequencies. Yes, with their help, having a powerful transmitter, you can broadcast a fairly large amount of information, but you need to know where exactly. If we are not sure that the message will reach its target, then why waste resources on long-term transmission? Rather, it will consist of short radio transmissions in the hope that someone will point their antenna at the right moment to the right part of the sky. And also at the required purity, otherwise, even if directed to the right area in the sky, the radio telescope will not notice anything. With types two and three, things are different. They have a huge amount of energy, and they would like to transmit colossal streams of data, otherwise why bother at all ? But how? And Kardashov makes an important assumption. They must create an omnidirectional emitter operating over a wide frequency band. This means it will be much easier to detect. He is like a lantern that is constantly on in the sky. If a civilization has the necessary receiving equipment, it will notice it. And the data transfer rate of an alien emitter depends on the width of the radio channel and the signal-to- noise ratio. Therefore, a powerful transmitter and a wide frequency band in which the information is transmitted are needed. And the less noise and interference at these frequencies, the better. This is the Shinen-Hartley theorem, for those interested. Therefore, according to the scientist, truly cool civilizations produce not narrowband signals like our radio stations, but broadband ones. It would seem that they could easily be confused with natural space objects. But Kardashov describes in some detail what exactly to look for. It must not be a monochromatic source, like a radio station on one wavelength. To transmit the maximum amount of information, all available frequencies must be used . But the radiation of the galaxy itself is uneven. At some frequencies there is more of it, at others less. Plus, interstellar absorption introduces additional limitations. Therefore, radio transmission must be carried out at frequencies where the influence of the galaxy is minimal. That is, the supercivilization is looking for the quietest place in the ether. Therefore, the spectrum of such a source should look like the radiation of a galaxy. Only the opposite: at frequencies where the galaxy emits weakly, it emits strongly, with a maximum at a wavelength of 3 to 10 cm. That is, we must look for a variable radio source. Moreover, its spectrum is either similar to the inverted spectrum of a galaxy, or has features that are unusual for natural objects , for example, rectangular details, cut-out stripes, or something similar. For a civilization of the second type, the source will be point-like, since the transmitter is very small in size compared to space objects. But type three transmitters can be scattered throughout the galaxy we observe, and the telescope can see a cloud of sources at once. After discovering such a source, it is necessary to investigate its variability, try to find frequency modulations in it, for example, the frequency of lines and frames, if it is a television signal. Kardashev estimated that civilizations of types 2 and 3, transmitting data in a channel with a width of 1 GHz, can send 104 bits of information in about a day. And this, just for a second, is the entire volume of printed and handwritten publications on Earth for the sixty- fourth year. A civilization sends a library the size of human culture into space in just one day. And it is necessary to understand that such interstellar communication will be one-way. Civilizations of type 2 and 3 do not attempt to communicate in a question-answer format. They broadcast scientific or cultural information simply because they can. Someone receives it and, over time, begins to transmit their own in response. And so gradually the galaxy is filled with radio stations, the broadcasts of which can be listened to. Nikolai Kordashov even identified two sources that he considered suspicious and that are worth looking into. They are variable and have the same inverse spectrum that he predicted. Unfortunately, it later turned out that these were natural objects. Kardashov's article largely set the criteria by which to search for artificial signals. She also explained how the development of civilization would affect the information it transmits. This is where the famous three types come from. But I still find it offensive that Kardashov is now associated only with aliens. It is thanks to his work that we have images of shadows, supermassive black holes, a radio astronomy observatory, and, in general, enormous progress in the field of radio astronomy. The academician, in fact, was n't given for aliens, but it turned out like in that joke about the King and the Goat. I'll leave a link to a short article on the N+1 website about this scientist's more serious achievements . It turns out that Kardashov was one of the first to think about how to connect the stars into a single information network. Of course, the Internet itself was still decades away, and such an interstellar network would require completely different technologies: architecture, methods of working with data. We'll talk about this a little later . But if humanity ever truly becomes part of such a network, it will be created not by science fiction writers, but by engineers and programmers. This means that knowledge of mathematics, physics, programming, and working with large amounts of data is required. And for our earthly civilization, such specialists are in demand today more than ever. And here, in order to not just use technologies, but to understand and create them, I recommend taking a look at the online master's program in software development from MFI and Skill Factory. Phi is one of the strongest technical universities in the country. The program is designed to combine fundamental university training with real-world industrial challenges. The training is built on a modern technology stack and covers the full development cycle, from business ideas to production. You shape your own learning path. Start with the fundamentals, master the Java language, and then choose your specialization in Python or Go. Experience is especially important for beginning specialists. In an online master's degree, you consolidate all your knowledge through practical experience. During your training, you will work with real-world tasks and cases from partner companies. The course is online, but it is a full-fledged full-time master's degree program with a state-recognized diploma from MEPhI. All student benefits, including military service deferments, are retained. And there is also government support. The cost of an educational loan starts from 210 rubles. per month for the first semester. Training from scratch. You can apply even if you have no connection with the IT field. The main thing is to have any completed higher education. To prepare for entrance examinations, Skill Factory offers a free preparatory course and consultations. If you submit your application now, you can gain access to additional events and materials from MEPhI even before your studies begin. So, to move into development or reach the next level in your profession, follow the link or scan the QR code on the screen and apply for an online master's program in software development. And it is quite possible that one day you will be the one writing software for an interplanetary and even interstellar communication network. And yes, guys, subscribe to our Telegram channel already. It's interesting there. For example, we try to regularly post news from recent events, such as what was discovered on the interstellar comet 3 Atlas or why this galaxy, photographed by the James Web telescope, is so strange. Also cool astrophotos. For example, for this shot, astrophotographers accumulated light for a total of almost 78 days. Adequate community. Well, almost. In short, we're doing great. Join us. However, time passed, and no one discovered the transmitters of civilizations of types 2 and 3 . No, of course, strange objects were regularly found in the sky, which people wanted to attribute to extraterrestrial civilizations. Cosmic masers in sixty-five, pulsars in sixty- seven. Strange and unusual things happen in space all the time , but to immediately attribute the strangeness of space to aliens is to give up. After all, to any anomaly you can say: “Well, that’s what aliens are like.” Even those very objects that Kardashov suggested taking a closer look at turned out to be blazars. These are quasars whose jet is clearly directed towards us. And various cosmic oddities gradually found explanations, despite the attempts of certain individuals to profit from hyped-up themes. As I explained in the Dark Forest video, the higher a civilization rises on the Kardashov scale, the more visible it becomes from a distance. In general, this is what my criticism of the Dark Forest hypothesis was based on . If a civilization is capable of building interstellar weapons, it almost certainly has a planetary- scale infrastructure. It's like hiding industrial production in the forest. If this is a moonshine still , then there will be no problems. However, a real interstellar weapon requires a colossal industry. A Dyson swarm that extracts energy by intercepting radiation from a star. Astroengineering structures, orbital factories, paradises of replicator machines, designers, transporters, and heat losses from the operation of generators, machines, and mechanisms will not go away. We can notice much of this from a very great distance. For example, in the spring of 2024, two works were published in which the authors search and, characteristically, find. Some Dyson sphere candidates are reviewed by Guy Thomas and Weiss. In one article, the authors selected seven suspicious sources from 5 million reviewed sources through a fairly thorough analysis. Of course, such an excess of infrared radiation could be produced, for example, by a dense dust disk or a cocoon, the particles of which would heat up and emit energy in the infrared range. True, very quickly papers appeared showing that at least some of the discovered candidates were active core galaxies, or more precisely, a special type of them called hot dogs. Yes, the strangers were able to make stubborn names again. To put it very simply, this is an active galactic nucleus with a black hole, surrounded by a dense cocoon of dust. The dust heats up and glows brightly, but in the infrared range. These studies show that we are also quite capable of finding a real Dyson sphere. Or, for example, to notice large, highly engineered structures as they transit the star's disk. Remember the hype around Tabby the Star. By the way, if you would be interested in hearing what is going on with this star now, let me know. And if we use the gravity of a star as a gravitational lens, then we can not only examine the aliens' astroengineering designs in every detail, but also study the composition of the exhaust of their spaceships, the lighting of cities, and so on. In general, you can’t hide in a real dark forest. Anyone who might pose a danger to their neighbors can be seen by all their neighbors. It's like in high-rise buildings. And here the argument often comes up that perhaps their technologies do n't manifest themselves that way at all. And we are actually looking for a hypertrophied modern humanity. But their communication is arranged in a completely different way. They draw energy from vacuum fluctuations, and dump heat losses from our brane, away from the heart. And dark matter is the waste product of their advanced industry. Perfect. And he made a mess, and didn’t bother anyone. Well, almost. Kardashov himself expressed the idea that as civilizations develop, they become cramped and boring within the confines of a single universe. They go to the multiverse or to worlds that are more convenient for them . And what might happen when one of these space elders decides to stay put is well depicted in the series Babylon 5. Incidentally, I wonder if the writers were familiar with Nikolai Semenovich's ideas, but as I've already said, all these so-called solutions to the Fermet paradox are still untested. and therefore unscientific. We can speculate about this , but the truth is that we see no hints of this new physics that would allow us to pierce spacetime, extract dark matter, and stoke the furnace with virtual vacuum fields. Only by increasing the scale of energy expenditure can we obtain new particles, new properties of fields and bend space, and not in any way. This means that it is highly likely that any development in the future will be quantitative rather than qualitative. The ceiling of technology, the great desert of physics, and the ancient civilization differ from the young only in the number of power plants and the thickness of history textbooks. This is how our world appears now, which means the problem remains. We see no traces of a super-civilization, be it debris, heat loss, or artificial signals. So, either they have all already met the terrible great filter, by the way, no to him. Or growing to type two in our world is incredibly difficult, and no one in the area has succeeded. They all sit on the first level, not even able to send each other a more or less lengthy message. But this is not the only explanation. What if we have the wrong idea about the interstellar communication channel? We are not talking about new physics at all, but about a slightly different data transmission technology . What if civilizations don't build galaxy-sized radio beacons at all? What if they have learned to transmit information so effectively that we simply don’t notice their signals because they go straight past us to the addressee? Perhaps this is what the American radio astronomer Vaughan Russell Eshleman thought and published this article in the journal Science in 1979. This was perhaps the first time that the gravity of a massive celestial body was used for communication, although the signal itself was transmitted using radio. That's the point. One of the first observational confirmations that general relativity correctly describes our world was the solar eclipse of 1919. More precisely, photographs of stars that became visible during the eclipse. The Sun is a massive object that should bend the trajectory of the rays of light from stars. Einstein was able to correctly predict the angle by which the stars would shift during an eclipse. In astronomy, this is called gravitational lensing, and the object that bends the rays is called a lens. And here is an important point. The larger the telescope's objective lens, whether it's a mirror, a lens, or a gravitational lens, the more powerful the telescope itself. The larger the lens area, the more light is collected, dimmer objects are seen , and the larger the diameter, according to the rayleigh criterion, the better the visual acuity. That is, we see all sorts of small details at a great distance. So, Ashlemon was the first to estimate that the sun would amplify a signal at a wavelength of 1 mm by hundreds of millions of times. The acuity of such a telescope will increase so much that at a distance of twenty light years it will be able to discern details up to 11 km in size . These are simply monstrous numbers. Roughly speaking, such a tool could be used to create a map of the distribution of radio communication towers across the entire planet. But this device can be used not only as a receiver like a telescope, but also as a transmitter. And the sun will focus the outgoing rays in exactly the same way as a radio dish or the optics of a powerful flashlight. If Ashlemon's calculations were correct, then it turned out that civilization did not need transmitters of gigantic power at all. It is enough to use the star itself as a giant lens. In this case, an ordinary radio station can turn into an interstellar transmitter. We could literally eavesdrop on radio broadcasts and watch television broadcasts in another star system, and in the future, even build an ultra-long-range communication line with another star, because the solar lens also amplifies the signal hundreds of millions of times. There was one problem, though. Since the sun is a lens, and a spherical one at that, where does it focus its rays? Well, there is good news and bad news. The bad news is that the Sun's gravitational focus begins at a distance 550 times further than the Earth is from the Sun. That's three light days. 18 times further than Neptune, or three times further than Woger, which flew away only 170 astronomical units in 1977. Well, that is, even Ashlemon understood that in his lifetime he would not live to see the Focus of the Sun expedition with the goal of watching alien TV programs. The good news was that the gravitational focus was not a point, but a long, thin focal tube, which the spacecraft would use to observe the alien system as long as it moved within its boundaries. There is no need to brake sharply, wasting fuel, or choose any complex orbits relative to the focus. You just fly inside, periodically adjusting your position. And, it would seem, fly to 550 astronomical units and use a lens. But everything turned out to be more complicated. The main enemy became not space, but the sun itself. The fact is that many factors will interfere with this method of signal reception. non-stationary processes in the solar corona, and the corona itself, the sun's small size, the shift of the solar system's barycenter, even the effect of general relativity, due to which space itself rotates slightly around our star. But it is the crown that causes the most interference. But the further the radio receiver flies from the sun in this focal tube, the further from the sun the lensed signal is formed . It will be a thin Einstein ring, as if encircling the sun. And it doesn’t matter whether these are radio waves, infrared or optical rays. Any radiation from the transmitter on the other side degenerates into this ring. That is, by flying even further, it is possible to reduce the negative influence of the plasma of the solar atmosphere. Ashlimon also writes that at shorter wavelengths, interference from the corona is also reduced, so the optimal wavelength for interstellar communication will be around 1 mm. This, by the way, is consistent with Kardashov’s work, published in the journal Nature, also in 1979. He also comes to the conclusion that millimeter waves are best suited for interstellar communication , although he makes this conclusion for different reasons. It was an inspiring idea, but it was forgotten for a decade. Mainly, perhaps, because of the very large distance to the place where it will be used. And then Eshleman's work never became known to a wide circle of space enthusiasts, otherwise it would have appeared in science fiction literature much earlier, as it seems to me. But it was at this time that the term we are talking about here, the interstellar internet, was first heard. It was proposed by science journalist Timothy Feris. And it's interesting. In his early publications he used a different name: the galactic central nervous system. Well, in the seventies and eighties the internet was pretty bad. Faris reasoned as follows: “We do not see exploratory ships of extraterrestrial civilizations. We do not see their traces on our planet either today or in the past. Numerous phologists pass by, since they do not have a very good evidence base. If we assume that the Copernican principle is valid and intelligent civilizations exist in the galaxy, then interstellar flights are most likely not their strong point. But perhaps they adhere to a different strategy. If sending a full-fledged manned ship to another star is difficult and expensive, then it is worth considering self-replicating probes that could be sent in small batches to a neighboring star system. Upon arrival, these replicators must find resources and energy, multiply and build a receiving and transmitting infrastructure. Thus, gradually, a civilization builds an interstellar network in which individual star systems become communication nodes. They continuously monitor other similar stations, transmitting and receiving data between systems. Each station becomes a library where information is stored and sent Halological information. The Feris interstellar network operates independently of any single world. It has a master program, similar to a set of genetic instructions, originally compiled by intelligent civilizations. This program allows it to efficiently process traffic, store and organize copies of everything it transmits, and continue to expand the network in accordance with traffic demands. In fact, even if a civilization dies or enters a non-contact phase of development, whatever that means, its information network will continue to function. If another galactic civilization ever discovers it, it will be able to connect and use its resources. The main thing is not to forget to broadcast its own information. Or rather, the network itself will most likely discover the subscriber and open broadcasts in their direction. As a result, stable connections between stars appear in the galaxy. And such a network is both a repository of knowledge and a monument to civilizations that may no longer exist in the galaxy . Well, because biological species, on average, exist for several million years. Why should civilizations be Otherwise? Reason provides knowledge of one's own mortality, but the network is a path to immortality in a sense. Feris, by the way, didn't really describe how exactly this network might be structured. He understood that small replicators couldn't build an omnidirectional beacon, so the signal would have to be a narrow beam from star to star. Otherwise, it's similar to the Kardashov network, only without Type II and III civilizations. So, there's the idea of continuous Kardashov broadcasts, Feris's narrow-beam signals, and Eshleman's gravitational lenses. The Italian astronomer Claudio Macone combined them all into one concept . At the turn of the 2000s and 2010s, he published several articles and even a book in which he tried to popularize and describe in detail the idea of ​​an interstellar internet using gravitational lenses. The gist is this. There will be a few formulas now, but if you don't like them, that's okay. I'll cover the main points. So, a radio telescope, unlike an omnidirectional antenna, concentrates the signal in a specific direction, meaning the entire The power is distributed only in a certain cone of radiation, like jets in gamma-ray bursts. This parameter determines how efficiently the antenna does this. In Russian, the term "antenna gain" is commonly used , although in fact, the antenna doesn't create energy; it only collects the signal into a narrow beam. So, gain depends on the signal wavelength and the antenna size. Well, to be more precise, on the effective area, but in any case, the larger, the better. So, it works with any telescope, by the way. But it's not enough to transmit a signal. It also needs to be received. Therefore, the total signal gain during transmission is the product of the gains of the transmitting and receiving antennas. Next, an important point. Signal amplification by an antenna is good, but in itself it's useless for us . The fact is that when we transmit information, that is, broadcast, for example, zeros and ones, there is a chance that the recipient will receive some of them distorted. This is due to interference, thermal noise in the receiver, even quantum effects. And in order to reduce the so-called coefficient bit errors, you need to either reduce the data transfer rate or increase the signal power, or more precisely, the energy per bit of information. This is precisely why the New Horizons spacecraft transmitted data from Pluto at a rate of about 1 kb per second. That is, it would have sent a 1 MB image in about 2-3 hours, and 10 MB in about a day. Reducing the data transfer rate was the only way out for the mission to Pluto. They simply wouldn't have had enough energy for a more powerful transmitter. So, signal power depends on the transmitter power, the gain of both antennas, the distance over which we transmit the signal, and its wavelength at which we transmit and receive it. I told you all this because in this way you can really evaluate the efficiency of interstellar communication. For example, at the wavelength of neutral hydrogen - 21 cm, the gain of the solar lens will be 57.5 dB or 500,000 times. And for the water line frequency of 22 GHz, this will be 8.5 million times. We mustn't forget about the receiving An antenna. Macon suggested it would be 12 meters in size. So, it turns out that by receiving a signal with a twelve-meter telescope through the Sun, we amplify it by 9 billion times for a wavelength of 21 cm. In practice, this means the following. Let's say we've landed on Alpha Centauri and want to transmit a signal from there to Earth at a frequency of 32 GHz at a rate of 32 kbps. This is similar to the Cheryumov-Gerosimenko Comet Socket Mission . A 40-watt transmitter is like a soldering iron. So, it turns out that we'll lose every second bit of information along the way if we pick up the signal with a seventy-meter deep space antenna. That is, it's useless; we'll only hear interference. But if we add a solar lens, the loss will be only five bad bits per 100 million transmitted. The losses are simply negligible. If we imagine that in the Alpha Centauri system, there's also an antenna at the gradational focus of one of the stars relative to Earth, then For reliable transmission, a power of only 1 mW will be sufficient. Approximately the same power is needed for Sirius or Bernard's Star. But you'll have to fork out a lot of money to reach the center of the Galaxy . For good communication over a distance of 26,000 light years, a kilowatt transmitter is needed. Well, like a microwave. Makona called such a system of two lenses a radio bridge. Regarding the capabilities of such interstellar bridges. With an unlimited frequency range and still a power of less than 1 mW, the data transfer rate for a paradio bridge between the Sun and Alpha Centauri will be 210 Gbps. Between the Sun and Sirius it's 100 Gbps, and Bernard's Star 16 Gbps. At greater distances, say, for example, between the Sun and a sun-like star in the center of the Galaxy, the data transfer rate will be a small but tolerable 5.5 kHz/kW. Although more power is needed, again, 1 kW. But in fact, the signal will not need to be transmitted over such great distances as the center of the galaxy. The most efficient exchange will be between neighboring stars. And so on down the chain. Let me remind you that all of this is calculated for a frequency of 32 GHz. This is a wavelength slightly less than a centimeter, but Kardashov and Eshleman talked about shorter waves. Millimeter waves will be less distorted by the corona of the sun or other stars. Moreover, perhaps it makes sense to completely move away from radio to the infrared, optical, or even ultraviolet range. The thing is , the higher the frequency at which we transmit a signal, the higher the data transfer rate. Therefore, for example, modern mobile operators are trying to move to ever higher frequencies. For example, 3G is 2.1 GHz, and then 24 GHz, although problems begin there due to the atmosphere. In general, high frequencies are everything. Here someone might lose their composure and ask: "Why do they even call this the Internet?" After all, it doesn't look like the real World Wide Web works. And I don't particularly like the comparison with the Web, just like with road network. The Internet is more like a worldwide postal service with oddities. When we open a website, our computer sends a request broken into many data packets. The main thing is that they have a sender and recipient address. That is, as if we cut a parcel into pieces and sent them along different routes. One will go through New York and Amsterdam, another through Oktaou and Sioul, the third somehow else. Along the way, the packets pass through routers, which determine where to send each packet so that it reaches its destination faster. For this, there are special routing protocols, the task of which is to constantly monitor the state of the network. If some node is overloaded or scoundrels have cut the fiber optic cable at sea again, the traffic will automatically go another route. If a packet is lost, the receiving end notices the gap in the sequence of numbers and notifies the sender about it, then the TCP protocol resends the missing data. This is why the Internet is so reliable. Even if part of the information is lost, the system notices the problem and automatically resends the data once. But there's a nuance. This entire mechanism was created for a world where distances are relatively short. A signal across the Atlantic Ocean takes about a few tens of milliseconds. Even a signal to the other end of the planet usually travels in a fraction of a second. Yes, the ping from Australia will be a bit high in some online games , but otherwise, it's livable. Now imagine that the transmission is going over interstellar distances. If a packet gets lost en route to the Centauri proxy, confirmation of the error will arrive in about 8.5 years, after which it can be resent. In such an internet, the "Refresh Page" button becomes a family tradition that your children will continue. It doesn't remind you of anything. That's precisely why an interstellar internet can't be built simply by increasing transmitter power. The problem isn't the radio signal at all. The problem is that the internet itself was designed for a world where your neighbor isn't four light years away, but behind the nearest router. In fact, everything we've discussed so far is more reminiscent of the old Feidneet network than of the modern internet. In it, computers weren't constantly connected . The node would receive the message and store it for some time until favorable conditions arose for further transmission. Usually, until night fell, when international calls were cheaper. Yes, Fidonet worked over regular telephone lines. When favorable conditions finally arrived, the node would forward the accumulated information packets further along the chain to the next node. A message could travel through the network for hours, and sometimes even days. Eventually, this system was completely replaced by the Internet due to its dynamic infrastructure, constant connection, fragmentation of information into small packets, traffic exchange points, and so on. But the funny thing is that Fidonet's communication principle is much more suitable for space. In fact, this problem has already been solved on the scale of the solar system. In the early 2000s, one of the creators of the TCP protocols, Winton Surf, developed a special protocol for transmitting data in space over interplanetary distances. His idea was this. A signal from Earth to Mars takes from 3 to 22 minutes. The response back takes another same amount of time. And for all these 2 hours of signal reception, poor unfortunate TCP will retransmit data. Because it will decide that packets are being lost. That's why SR came up with the DTN architecture. It works on the principle of "store and forward." There is no longer a continuous connection. There is a path, the data is transmitted. There is no path. We save what we received and wait until we can send it on. It's like the mail. A ship arrives at the port and picks up parcels from the mail. The ship is gone. The letters are sitting in the warehouse, waiting. Well, or again, it's similar to Fidonet. Even on Earth, the router decides how to send a packet of information based on the connection state. But in space, it's essentially known in advance where Mars will be when an orbital repeater comes into Earth's reception zone , that is, when the communication window will open and close. Therefore, the route and communication schedule are calculated according to the laws of celestial mechanics instead of dynamic routing. Well, yes, in the interplanetary Internet, you can't just cut a file into small pieces and transmit each of them separately. A few packets will be lost and the entire connection down the drain. That's why they came up with the so-called bundle for the interplanetary internet. It's like a more complete and meaningful piece of transmission. An archive of scientific data, a photograph, a piece of video recording. It's transmitted in its entirety and stored in its entirety on a network node, awaiting the next communication session. And it's already working. The system has been repeatedly tested on the ISS for communication with the ground, the station, and spacecraft, including lunar ones, including via optical communication. The operation of the interplanetary internet was also tested on the Deep Impact spacecraft. If in the future we do have lunar manned stations, and then long-term missions to the Moon, then the internet architecture for them is already ready. If all of the above is extrapolated to the interstellar internet, then something similar emerges. A little further beyond the boundary where the star begins to focus its rays, receivers and transmitters of information are located. For the Sun, where the gravitational focus begins at 550 astronomical units, it's better to place repeaters, well, a little further away, and even better, two to four times further, to minimize the negative influence of the corona. Each star system, it turns out, is connected not with the entire galaxy at once, but with a small number of nearby network nodes. The reason is simple. Each direction requires its own communication bridge, located in the corresponding focal region of the star. Therefore, the galactic internet resembles not radio broadcasting, but a network of trunk communication lines. Messages are gradually sent from node to node, overcoming thousands of light years in many successive transmissions. To ensure high data transfer rates, each node of the interstellar internet is connected to only a few neighbors. But at the same time, in addition to its own information, it also transmits data from other network participants. So , while located in their cozy solar system, internet users have the opportunity to receive information from the other end of the galaxy. If the distance between civilizations is great, perhaps they can build router systems, for example, send replicators to the star system, where they will create an infrastructure for interception and relaying interstellar messages. In fact, several additional bridges are created between civilizations , providing more reliable communication. For these purposes, slightly more massive stars compared to the Sun could be used. Something like Sirius or Vega. The main thing is that such stars are not very variable. By the way, I just now thought that maybe this is why the alien message in the movie Contact came from Vega. And yes, unlike the Internet, the interstellar network cannot ping the connection quality. Therefore, the connection begins to work like interplanetary internet surfing, only in slow motion. Each star system, no matter whether it is inhabited or a router controlled by artificial intelligence, must analyze the proper motion of the stars, the oscillations of the systems' centers of mass. Otherwise, you never know, there are massive planets there that will rock the star and simply shift the gravitational focus in the direction of broadcasting. Moreover, over time, some stars will move too far away, and the network must adapt to this, creating channels connections with new systems. Well, again, this is also a continuous broadcast of entire information packets, like in the interplanetary network, and not short fragments, like in the real Internet. Each packet is duplicated many times with a certain time interval. This allows such a network to be used like the Internet before the era of social networks. There is virtually no direct communication, because it can take tens of thousands of years to reach distant nodes. But in the early Internet, it wasn't necessary, well, except for email. A person simply went to a website and looked up the information they needed . Basically, it didn't matter who created the site or when. And even if something happened to its author, their information remained online as long as the hosting was paid for. The same is true for the galactic Internet: if civilization perishes, its last packets will circulate between routers for a long time, becoming a kind of monument to the entire planet. This Internet bears little resemblance to the one we are used to. There is almost no direct communication. You can't write comments and get a response in a minute, you can't conduct a video call. You can't even be sure that the author of the site is still online. Alive. Essentially, it's not a conversation network, but a library network—a vast galactic archive where civilizations leave their knowledge, art, history, and scientific discoveries for those who know how to listen. And this is where the video could end . We've painted a beautiful picture of an interstellar information network. And if it doesn't exist yet, it could emerge in the future, with or without our participation , if we're not alone in the universe . But perhaps it's not that simple. There's one inaccuracy in everything I've just described. Macon viewed the Gravitational Focus Star system as a fully-fledged telescope, so he simply calculated the gain of the interstellar bridge using the sizes of the receiving star and the transmitting star. The results were very encouraging. But in 2024, a paper was published in which the author attempted to more accurately estimate the gain created by a stellar bridge made of two lenses, using both geometric optics and wave optics approximations. It turned out that two lenses don't significantly increase gain compared to a single lens . The beams focused by the transmitter lenses won't travel strictly parallel, so not all of the radiation sent by the transmitter will reach the receiving star. And if you do the math carefully, the interstellar bridge turns out to be of little use. Only the star's amplification during transmission can be beneficial , but not during reception. Quite unexpected, huh? I've been going on and on about it, so that's it . However, it's too early to get upset. The fact is, our old friend Vyacheslav Turushev, around the same time, published a paper in which he examined the same two-lens bridge as a transmitter and receiver within the framework of wave optics. And it turned out, no, things weren't as rosy as Macona's. Nevertheless, a two-lens bridge still amplifies the signal compared to a single-lens one. Or rather, as the second lens further focuses the light from the first lens, which is, of course, a good thing. This provides additional power to the received signal, but it also changes the geometry of the beams. Double rings appear there. Einstein's lenses, located so close to each other that they can simply overlap and distort the signal. The second lens also significantly amplifies noise, which also impacts data transfer speed. Therefore, we must either use a single lens or switch to even shorter wavelengths: ultraviolet or X-ray. I think in the coming years we will learn the best way to build interstellar communication: with one lens or two. Although, in fact, the internet can be built with either one or two lenses. This affects the transfer speed, but even a single lens, that is, a single star, provides a colossal increase compared to a simple radiant antenna or laser emitter. lem, which is, of course, preferable for the Internet. Simply put, in the case of a single lens, the emitter flies behind the star so that the signal sent from there is focused in the direction of the receiver, and then it can be received by space telescopes and transmitted to subscribers in need. In the case of a two-lens bridge, the signal is received by a telescope in the region of the star's gravitational focus and then transmitted further throughout its stellar system. The difficulty here is that the focal line of the star itself is very thin, so the receiver, and most likely even a whole swarm of receivers, needs to have a very good idea of ​​the orbit of the transmitter in another star system and the delay in transmitting the signal. Otherwise, the beam from another star system will not reach the receiver, and the information goes nowhere. By the way, Torushev also expressed the idea that it would be possible to try to search for these signals. If our planet accidentally ends up on a line connecting two linked systems, we might intercept part of someone else's message. In fact, for a moment we will find ourselves, as it were, in the path of a gravitational focus, and around the transmitting star, as I already said, an Einstein ring will appear, in which the radiation of the transmitter will be concentrated. If it is a laser connection, the ring will be very bright. and, by the way, monochromatic, that is, it definitely cannot be confused with anything else on the source spectrum . Yes, it is impossible to see it with modern optics, but it is not necessary. The same principle applies here as when searching for exoplanets using the transit method. The telescope simply records the change in brightness of an individual star, and the processing and analysis of scientific data will do the rest. The same is true here, only the phenomenon, apparently, will be much more fleeting. However, it can already be detected by existing technology. The main thing is that the telescope is pointed at the right place at the right time. Well, and so that there would be at least someone there. At the end of the video, I would like to express one thought. I came across a book by Alexander Ponov from 2007. Universal evolution and the problem of the search for extraterrestrial intelligence. This is not popular science, so I don’t recommend it to those looking for light reading. And in general, in some places, what Panov is now saying in his numerous interviews is simply brutal. Therefore, I do not recommend it either. Although it is easy to speak, you can’t argue with that. However, in 2007, Alexander Dmitrievich was clearly more careful with his conclusions. So, among other things, this book also talks about the idea of ​​an interstellar information network, although without technical details. And there he expresses the idea that if the lifespan of an intelligent civilization is limited, then connection to the galactic information network can significantly extend this life. The point is that, together with scientific knowledge and cultural information that is present on the Internet, civilization can find answers to existential questions, solutions to crisis situations, and support. This information will allow you to save money somewhere, since you don’t have to follow a path of development that is obviously losing and avoid making the same mistakes that have already been made in the galaxy before you. And other cultural influences enrich the local culture, preventing it from withering and stagnation. It seems that this conclusion is partially confirmed by the history of our planet. If I'm wrong, let historians correct me in the comments. But it seems that people and cultures that at some stage of development withdrew into themselves, consciously limiting contacts with the outside world, noticeably lagged behind those who were included in international communication. Culture and economy gradually stagnated. The standard of living of the people remained quite low. Many people have gone through this, and not just once. China, Japan, Korea from the relatively recent example of Albania during the time of Hoxha. And changes for the better in these countries began precisely when they emerged from isolation. Therefore, if some Darthwider or Emperor Polpatin decides that in order to maintain power in his empire, it is absolutely necessary to protect his subjects from foreign influence, in the long and even medium term the consequences will be catastrophic. Although blocking the interstellar internet is not so easy. It would seem that there is nothing to mess around with? In the case of a two-lens bridge between stars, it is simple to turn off the transmission reception infrastructure. But even strengthening one lens gives a good increase. Therefore, any owner of an average-quality telescope by future technology standards could connect independently. After all, for a single-lens bridge there is no need to fly far from the star. Well, yes . To do this, other star systems would have to reduce the speed of data transmission to this system, but nevertheless the connection would simply remain at a lower speed. And prohibiting citizens from pointing telescopes at a certain part of the sky, well, that's not it. In general, the interstellar internet can be added to the arsenal of explanations for the so-called Fermet paradox . Everyone is online, but we haven't been connected yet. Maybe they have n't made a decision yet and are studying our radio broadcasts. The current season is particularly interesting. But inviting such crazy guys into your group might not be the best idea. Either our radio signals haven't reached them yet, or there's no one there. Or maybe the connection works differently and the electromagnet and the range are the Stone Age for them. In short, I don't know. Well, I hope you found it interesting to talk about this topic. Thanks for watching, friends. As a reminder, the description includes links to Telegram, which you absolutely must subscribe to now, as well as to resources where you can support us, and to publications on this topic. The number in brackets is the article in the file. Are you curious? Go there and read where I learned all this from. Well, yes, likes are always good. Don't forget about the new video, or rather, a couple of them are already in the works. No to the great filter and see you later. on Shklovsky Street