Magnetic sails could be used for braking, but they are only really useful for braking from ludicrous speed to astonishing speed, that is from a high fraction of the speed of light to a low fraction of the speed of light. The braking effect is minimal once you get down to about 1000km/s, which is still much too fast.
However this paper suggests that a very lightweight mission using magbraking would be possible at much slower speeds. https://arxiv.org/pdf/1707.02801.pdf
Perhaps the best mission profile would be to dump most of the payload on approach to the destination star; that means you’d probably arrive with little more than an advanced version of Rat Avatar’s 3D printer. The chances of failure for such a mission would be very high.
Note that biological replication systems have a strategy to cope with the possibility of a high rate of failure- send lots of 'em. Fungi emit vast clouds of very lightweight spores, but only a tiny fraction survive.
I am pleased to note that the main image on that page is one of mine. I’ve been knocking out images of Dyson Spheres for years, and people often ask to use them. But that doesn’t mean that I have any particular belief in their likelihood - the more we look, the less we see them. Even if an advanced civilisation did build a power collection swarm, chances are that it would be much too small for us to notice at this stage in our search.
No, but I could- the shadows are consistent with fuzzy dust balls, possibly planets with large rings or accretion disks around them. So perhaps this star is surrounded by fuzzy megastructures that look like dust from a distance. An advanced civilisation could surely make a megastructure that looked exactly like dust.
This highlights one of the problems with building megastructures of any kind - if they look un-natural, anyone can see them- including any ‘dragons’ or ‘wolves’ that might be out there.
Well in this case it is less stable. While not perfect yet compute time (and FP accuracy) is the main limiter on ephemeris reliability right now. The point is that deconstruction of a planet will have impacts on the inner system, but if we lived on Jupyter or didn’t care about asteroids that may be OK.
The point is that gravity is an apparent force caused by the geometry of spacetime, and so it doesn’t matter if matter is in a similar orbit, but in a sphere. The curvature will be different when you disassemble a planet and the resulting perturbations will be different. Maybe these superior aliens produced good hardware acceleration for arbitrary precision decimal instructions; and not being limited by finite math in FP, or compute time they have a unified theory that shows it is a problem
At least mag sails have less of a supply issue. Unfortunately we live in a part of the universe where Xeon is fairly rare and Argon is comparatively inefficient in ion thrusters. Radon may be an option for mechanical drones, but for obvious reasons not an option for human trips. There are several resource challenges that will be difficult to overcome.
In General:
While I am obviously far more in the experimentalist then the futurist camp; IMHO the greatest thing that the apparent Fermi Paradox teaches us is the limitations of classical sentential logic.
That said, I hope people still keep working on a viable hypothesis on both detection and travel. Working on small scale, automated and highly efficient resource extraction may be a good first step.
At least they would have their fill of alligator shaped paper clips and colbert heads with cephalopoda bodies. Oh and calibration cubes and purge blocks…the herpes of additive manufacturing.
While not earth shattering, and with bad music because static and router noises hit some crazy copyright claim and was replaced with a random song, I even made my own FP4, and electrocoated the circuit boards. I even had a vapor deposition chamber to try making some electrical components before I realized my design was going to emit Xrays and chickened out.
Anyway, I was working on this to try and help decentralize manufacturing for countries with less resources in harmony with the RepRap idea.
So while not an expert my experience in this indicates you would need a huge army of specialized robots in many different sizes imho. And I think that the typical efficiency numbers are from people who don’t realize how hard it is to improve on some of these. I assume most people would be shocked by how large the waist stream is on some of these operations, especially around refining materials, or producing metallic forms of elements.
Still I am far more impressed by your ability to draw, and you are the artist behind the ‘artists conception’!!! I can’ even draw a stick figure without getting kicked out of art class.
Unfortunately, Tabby’s star’s spectra when dimming suggests that the obscuration come from very small particles the size of dust or grains of sand. It’s still a mystery how a star of that age could have a dust cloud around it, but it sure looks like dust.
One of the problems with this whole debate is that we are approaching it from a human point of view, and our own existence is the only data point we have, and our suppositions are based on the technology we know.
We have zero idea what might motivate an alien civilization. We have no idea what energy needs they have, what energy sources they have, or what technology they have to extract it. For example, we discovered solar cells in the last century, so we assume that capturing all the energy from a star must be done through the use of a sphere of solar collectors. Maybe in 10 years we will discover something that allows us to extract the sun’s energy in some other way, and we’ll then say, 'well of COURSE there would 't be Dyson Spheres - no civilization capable of building them would use such an inefficient way to gather energy when they could have just used ‘quantum piping’ or whatever new tech we will have discovered. And maybe if there’s a way to detect that form of energy collection, we’ll look to the sky and see it everywhere.
Assuming we can make judgements about what other hypothetical civilizations must be doing based on our piddling knowledge only discovered in the past 100 years or so strikes me as very arrogant. For example, we make judgements about how easy or hard it is to travel at high speeds in interstellar space, despite the fact that we have never done it, and have just barely cracked into the Kuiper belt. We don’t even understand the what makes up the vast majority of our universe.
It’s entirely possible that there is a ‘great filter’ that locks civilizations into their own solar systems. Some property of interstellar space yet discovered or just the math of traveling such long distances.
Then there are the motivational aspects. We assume that interstellar travel would cause a civilization to expand endlessly. But would they? If you spent a significant chunk of your resources to visit the nearest star, and just found a new collection of hostile planets and not much more, and you continued that for another hundred stars, at what point might you just decide, ‘we’ve seen enough’?
The law of large numbers does not necessarily apply here if the Drake equation gives us results that indicate a small number - say 1-1000 intelligent civilizations - exist in our galaxy. With that small a number, the fact that none have colonized the galaxy could just be a fluke or a result of statistics. Maybe it just so happens that none of the ones that happened to arise here cared or could for one reason or another.
I’m not sure what you are arguing for. Sounds like you are saying that we’ll need lots of energy. Which is why I think that we will build solar collection in space.
Right, there are reasons that they may not follow this path, but to answer the fermi paradox, you have to explain why not a single one would have.
Not sure, once again, what your argument is here. that we will need lots of energy? Sure, we will. And to the last point there, making it in orbit means you don’t have to get it off a planet.
You mean as far as uses for the waste energy?There’s actually quite a number. Or if you are talking about how you are going to reject it, that’s easy.
How do you think we should go about detecting intelligent space fairing life, if not looking for the structures that they would build?
Beyond our current production capabilities, you mean? sure, I don’t argue that for a second. Beyond our eventual capabilities as we ramp up space exploitation and manufacturing? What are you saying the hold up is?
Or are you saying that it somehow breaks the laws of physics?
My null is that we are the first or only intelligent space faring life within at least a couple billion light years. Nothing about these claims of impracticalities of space colonization moves me away from that.
Wikipedia mentions this work in the first segment, but links to a cite. http://www.rfreitas.com/Astro/ThereIsNoFermiParadox1985.htm
You do not need to subscribe to theory of modal logic to see how the limits of syllogistic logic is what gives rise to the apparent fallacy.
Syllogistic logic depends on absolutes, and falls down in cases like this.
No, as a defender of Fermi’s Paradox, which I have just provided a cite where I describe the logical problems with it, you need to provide evidence that the assumptions it makes are valid.
But it is not just an energy problem, it is a resource and reversing the flow of time problem. You are begging the question by claiming that, because it will take a lot of energy to make a Dyson swarm, that we obviously need to build a Dyson swarm.
How about looking for effects that are far more likely and practical. Judging sociaties based on their energy consumption sounds like stacking the deck to me.
Note that we may just never know too, why couldn’t they just work on more efficiently using less resources? As a defender of this idea you have to justify why that isn’t the most likely course of action.
Both, it breaks our current understanding of material science, and resource availability. There are lots of holdups, challenges and problems. We don’t know if they will be solvable in the future and so why are you arguing from a position that they will be solved?
First, you have to define intelligent, second why do you make that distinction. Outside of the unknown paths of evolutionary pressures why is there such a distinction between the two? That is special pleading IMHO, can you demonstrate that our intelligence was caused by anything more than evolutionary advantages which arose due to limitations of our common ancestors limitations and particular adaptations?
What does it mean to be a defender of Fermi’s Paradox?
The paradox is simply, if the universe is as vast as it seems to be, then where is everybody?
The answer that I come to is that we are the only intelligent space faring species.
It makes no assumptions, other than the vastness of the universe, and the lack of evidence of other intelligent life.
What assumptions are you thinking of?
Not sure what you mean by “reversing the flow of time”. When did time travel ever get invoked?
And as far as resources, well that’s why you go to space, to get them.
What reason are you thinking that they would use less resources? Throughout our history, when we found a way to do something more efficiently, we didn’t use that as a reason to reduce our consumption, but rather the opposite.
I don’t have to justify why this isn’t likely, you have to justify what it is exclusive. I find it unlikely that there is other life out there that has gotten to the point of basic agriculture, much less space travel. You seem to find it likely that there is quite a bit of intelligent space faring life, but not a single one of them used space based solar collection.
What exactly is it that breaks our understanding of material science? We have solar panels in space right now. They seem to work fine enough. What is is that you think would happen as we build more to make them impossible? As far as resources availability, that’s the entire point of this discussion, that is where the resources are.
Now, I do think that we will improve our technology to the point where what is difficult now will be much easier or even trivial in the future, but I do not know what holdups, challenges, and problems that you are pointing to that makes this impossible.
100 years ago, just basic space operations that we take for granted today would have been considered to be pipe dreams and impracticable.
I really don’t understand this question. What distinction am I making? What are the “two” that you are talking about? And why would I need to demonstrate anything about our evolution to point out that the universe seems suspiciously empty?
Too long to quote,
But lets go back to what Fermi’s conclusions were.
Bolding mine, and intermediate cite due to dead tree references.
My opinions seem to match Fermi’s so instead of me doing all the work, how about you calculate the energy costs and material needs to produce a Dyson swarm or, alternatively provide numbers around interstellar flight and colonization.
I have provided numbers and I have the feeling that the goal post will just be moved once again.
People assume Fermi suggested that crazy concepts like Dyson spheres were required or intelligent life doesn’t exist etc…but this is why I am saying it is upon you to prove that these concepts are even possible, let alone practical or desirable.
asteroid Pallas is 2.17×10^20 kg in reference to the 0.78 grams per square meter of sail of 100% reflective material discussed before.
That is a factor of 4 lighter than the lightest material we have, and that material is not reflective. But lets say that you could make that material from carbon, with the previous stated energy requirements that would take
1.73600 × 10^23 megajoules of energy just to make that much carbon fiber. And you would need a a huge source of hydrocarbons to make it.
173,600,000,000,000,000,000,000,000,000,000 megajoules, or to rephrase this, the energy of 173,600,000,000,000,000,000,000,000,000,000 mini coopers going 161 km/h or 100mph.
Consider how much energy that is, and that is just to make the material, not to transport it or mine it etc…
Thus the reason for Dyson and others suggesting the dismantling of entire planets, while assuming unreasonable energy efficiencies like 10:1 for dismantling and getting into orbit mirrors from Mercury.
As I used Megajoules which is not common, let me put this in context.
WAG estimation on energy to just make the material today.
73,600,000,000,000,000,000,000,000,000,000
Total world annual production of energy today.
270,864,000,000
Please elaborate or link to further information. For I’ve seen many strange things already – including, but not limited to, “Bloody wolves chasin’ me through some blue inferno!” – and am genuinely motivated in having all that is rightly debunkable, debunked-the-F-out of related [earnest] discourse…
*(NB: No one with any self-respect wants to be peddling Ufological lunacy that’s tantamount to religious promulgation; with the former often being defined as a modern incarnation of latter mass-delusion – see: Scientology) *
As far as those conclusions, we know that interstellar flight is not impossible, as we have detected things in our solar system that are thought to have come from beyond the solar system, so there are no shells or anything like that preventing material from moving from one to another. Difficult, sure, and often chosen to not be worth the bother, maybe. But always? That’s a different proposition.
Technological civilizations collapsing before it happens, well, that’s the one that I find most likely out of those options, but I also find it quite depressing. It could very well be that there are billions of failed civilizations on worlds in our galaxy that used to be full of life, until they evolved intelligent life which destroyed itself along with enough of the ecosystem that it never recovers. We may be able to witness that answer to the paradox within our lifetimes, the way things seem to be going.
If you were talking to James Watt, standing next to his steam engine, and you said that his invention could be used on a ship to transport cargo, would you accept the argument that that would mean that in a few hundred years, 10 trillion tons of cargo would be moved by sea every year, and you’d be asked to provide specific energy costs and materials as to what it would take to build that many ships and how much energy it would take to move them, and it would be concluded that it is impossible to do, and that it is an absurd proposition to even think about.
Yet, that’s what we do, every year, and it started with a single steam ship.
Was this done because a single govt or other entity produced all these ships and all the cargo to be transported? When the first container ships were built, was their ability to move cargo in doubt because of the costs of building an entire fleet?
I cannot move the goalposts, as I have not set them. You have made some mistaken assumptions about my positions, and that may contribute to your feeling about that, but that is not on me.
I have not talked at all about direct interstellar travel and colonization, but rather that it would happen slowly, as we expand, so questions about interstellar flight are not relevant. And the numbers to produce a dyson swarm are just as useless as the numbers required to produce our entire fleet of container ships when talking about building a single or small fleet of steam ships.
Fermi asked a question, and that question goes on. He was not the definitive authority on the answer. I don’t really care what you are saying that other people assume about it.
For reference, the sun puts out 3.86 x 10^20 megajoules per second.
The energy requirements for that could be met in about 500 seconds. Let’s be real generous and call it half an hour for rounding errors.
And you are making many assumptions about the amount of coverage, as well as the surface area required, as obviously, the closer you are to the star, the less surface area.
Tiny, actually. Huge compared to a mini cooper, sure. Tiny compared to what is available to a space faring civilization.
I do like the mini cooper as a unit of energy though. Does that mean that a megacooper is a terajoule?
The idea isn’t that you start with a dyson swarm. You start with a single asteroid mine. You have a single solar collector. Then you build another mine, and another collector. Then you build a few more mines, and a few more collectors. Rinse repeat. If somewhere down the line, you decide to start pulling in even more resources, and you find that you need to start mining a planet down to nothing in order to do so, that is something that will be considered when it comes time to consider it.
You don’t have to completely enclose the sun, either. There is no real need to, and in fact, doing so would be inefficient, as it would be hard to do without some collectors being blocked out by others an unacceptably large portion of the time. You also don’t need to blot out the whole sun to be noticeable. We detect when a star dims by a fraction of a percent, we would notice if any of the stars we are monitoring were blocking any significant amount of the star’s light, just as we did with tabby’s star.
The richest man in the world is betting on asteroid mining being possible. Several companies are being formed for the specific purpose of extracting minerals from space resources. If it was such an absurd notion, then they would not be doing this. You have made an argument as an appeal to authority to how people remembered a conversation with Fermi. I admit that I am making a similar appeal to authority, but to people who are putting their money where their mouths are.
Since you have accused me of moving goal posts that I have never planted, I will go ahead and plant them, at least then we can be on the same page as to what I am proposing.
The paper in question of the OP, in the abstract, at least, only says intelligent life, and if we want to take exception to that description in the abstract, by saying that there may be forms of intelligent life that never develop any sort of tool use, much less space flight capability, then that’s fine, but that is addressed more in the bulk of the paper, in that they are only looking for tool users that have the capability of making a noticeable presence in space. So, in that, we can, I suppose agree that there may be forms of intelligent life that never develop space technologies. Not just aquatic or sedentary species either. If an intelligent species evolved on a world with 4 times earth’s gravity, the chances of them finding space exploration to be practical would be slim. They may be far beyond us in all scientific subjects, but have never done anything more than send a few sounding rockets out of the atmosphere.
The people writing the paper took a look around, and didn’t see any signs of galaxies being swallowed up by growing dyson swarms, and so concluded that there weren’t any. They did make some assumptions, that if you build one dyson swarm, then you will go to your neighboring stars and do the same. I see no problem with this. If you have the availability of that much energy and resources, then the skip to the next star (especially if those being sent are immortal due to biology, cybernetics, uploading or just computer AI) is not that great. Once you have a few star enclosures under your belt, there is little reason for you to stop.
So, can we agree that if you build one dyson swarm, it is likely that you would build another, and another, and that nothing would really stop you until you run out of stars? If not, what do you think would stop you?
To that end, if we do have mining in space along with energy production, what would stop us from increasing that capacity until we use all the available energy from the sun, and all the available resources from the solar system? There may be political reasons why we should not disassemble some planets, but I don’t think that we would really need to anyway. Maybe Mercury, but that one is already pretty well stripped down to its core. throw in some of Jupiter’s moons as well. If it really comes down to mining Mars or Venus to nothing, by that point, the vast majority of production would exist in space, and likely our population would too, so nostalgia over planets may not be enough to protect them.
So, can we agree that if you have one self sustaining asteroid mine, along with solar collection to power it, it is likely that we would build another, and another, and that nothing would really stop until you run out of material? If not what do you think would stop you?
Now, the technology to develop our first asteroid mine is not trivial. I am happy to grant that. But, I don’t really see anything in the laws of physics that stop us, and I don’t see any reason why people would stop trying until they have either succeeded in bringing back material from space ventures, or until the law of physics that says that it is impossible is discovered, or humanity falls and is wiped down to the point where food, clothing and shelter are of much greater import, and nearly as difficult to obtain as asteroid materials are now. What do you know that Jeff Bezos doesn’t? I’m sure he would like to know it too before he invests more money into what is, according to you, a futile venture.
To answer the fermi paradox, you don’t only have to show why we won’t grow our space industries until they are noticeable from across the way, you have to show why none of the presumably countless other intelligent beings that have evolved in our galaxy did either. The only solution to that that I have seen that makes sense is that intelligent species inevitably and always wipe themselves out when they get to about our stage of development. That was Darren Garrison’s answer to fermi’s question, and while I hope he is wrong, it is at least an answer that makes sense, and I can respect that.
There were other answers, like developing technologies that violate the laws of physics as we know them, and thereby, making such endeavors useless, but that, to me is Syfy, relying on the laws of physics being different than as we know them. Possible, but not really worth discussing unless we have good reason to think that the laws work that way. But, sure, if we develop a zero point energy source, or other over unity type of device, then we would have no need of harvesting energy from the sun. I suppose if we wanted to go that way, we could say that the lack of evidence of any other civilizations harnessing energy from their star indicates that there are better energy sources to be had, once we better understand the laws of physics.
That we as a species would simply one day decide to not continue to grow is not something that I can really agree with. We have never done that in the past. Life has never done that in the past. Life always fills every available niche it can find that harbors it, then evolves itself to fit into new niches which will also harbor it, sometimes even modifying those niches to be better suited for life. Individual people and even nations may turn their back on growth, but humanity as a whole won’t. What makes you so sure that we will suddenly stop doing what life has been doing on this planet for billions of years, that we as a species have been doing for tens of thousands, and that we as a technological people have been working on for the last few decades?
The most basic definition of life would be something that performs work to reduce its internal entropy by increasing the entropy of its environment. Anything like that will grow, and will utilize any and all resources it encounters to do so. The idea that any form of life, no matter how alien, would ever say, “Oh, we’ve grown enough, we’re good now, no more need for expansion” goes against pretty much everything required for life to exist in the first place.
In conclusion, I’ll go with three possible answers to fermi’s inquiry.
First, we all die, because we kill ourselves. All technological civilizations are just on the inevitable path towards self destruction. Sad, but, even sadder, likely.
Second, we develop technologies that allow us to grow and expand that do not require input resources or energy. Cool, but unlikely.
Third, we are the first to develop and deploy these technologies within a large enough volume of space that any other intelligent species are outside our current light cone. This is unlikely for an individual species, but is inevitable that there is one.
The average distance between two asteroids in the asteroid 2.5 times the distance between the Earth and the Moon. If all the asteroids in the Solar System were put together, the size of the resulting rock would be much smaller than our Moon. This is why many of the Dyson type solutions assume using the core of Mercury to produce hematite.
But we do know some limits which will require fundamental changes to physics to resolve, even if it is desirable to collect energy at this scale. While you are making these claims why do you also ignore the other options like maybe more advanced civilizations figure out cold fusion, or better yet theoretical quark fusion instead of building huge invasive structures to try and collect a fraction of a percent of a fusion process that in itself only releases a small fraction of those fusion products as energy (less than 3% IIRC in the case of the sun is emitted). Microwave energy transmission is assumed to be limited to a few 100 km at most as an example and the inverse square law is not kind to it at all.
But people who subscribe to the Fermi Paradox are also ignoring that we are in that newer studies suggest we are among the first 8% of earth like planets that could evolve in the universe.
Life evolved remarkably fast on Earth, and with the complex organics detected on Enceladus I would be surprised if we don’t at least find RNA in the near future.
While we do have a sample size problem this isn’t unexpected as acetylene, formaldehyde, methane, and propane may be common but largest and most complex organics found in the solar system and some were too large for the instrument couldn’t analyze them.
All indications are that life is very likely to happen when conditions are right
So the idea that futurist press where these Dyson sphere types of structures or expansion is is inevitable is what is completely without evidence at all. And while there is new physics to be learned and far more unknowns than knowns the assumption that we don’t know that we are approaching limitations, or know that there are potential bounding events is a pretty bold assumption.
While I am not claiming expertise or total knowledge most futurist seem to completely ignore or are ignorant of the challenges to mining, refining and processing materials and how much effort is produced.
The autonomous self replicating robots idea is just simply hand waving away the reality that the mining, processing and manufacturing industries would absolutely embrace even simplistic automation that even gets close to approaching this goal.
Even ignoring these resource limitations, some of these needs are NP-complete or are “decision problems”, meaning that the problem is to decide if something is true or not.
Where do you source and refine the molybdenum and tungsten, how to get the carbon to carbonize steels, how to you temper them to avoid shattering. How do you re-hardface your digging implements. As you are pumping massive amounts of energy into asteroids and or Mercury, which has no atmosphere how to you cool the area when the energy you are transmitting is utilized and ends up as that waste product of heat.
Remember in space that you can only get rid of 100 to 350 W of internally generated waste heat per square meter of radiator.
Ore beneficiation on site which will not be an issue for rare, high value metals asteroid mining. Will require lots of mass in gear and insane amounts of cooling etc…
The point is that we will probably find other ways to detect life, if we are that lucky, and those methods aren’t dismissed by a claim that this form of project is even likely let alone possible.
You can’t hand wave away the real issue with the Kardashev scale as a filter because of items like steamships. Which was an incremental improvement with a societal goal, and economic benefit.
The Earth gains no benefit from that additional power, and in fact trying to get more solar energy to the Earth would result in the death of human life on the planet. What you are talking about is massive projects to protect ones linage and vanity.
I will die, you will die and eventually on a long enough time scale we will all die. If life is common throughout the universe, even if it is not intelligent why should we even care about spreading around the universe. We can focus on making the most of our time and enjoying that we had it. What is the value of huge projects to inefficiently deconstruct the solar system so that your particular line of DNA keeps replicating?
To me it seems to just serve our own vanity. While I can personally understand a quest for knowledge that is not how you phrased your argument. Even if we could produce these auto replicating robots that can build this type of structure, I would find it personally immoral to do so.
As you referred to the rise of progress, remember what happened to the inhabitants of the new world. 90% of the population died and it is quite likely that if life is common and interstellar travel is possible that you would either be subject to, or subject someone to a plague because of why? It makes us sad that we only had the time that we had?
TLDR; nothing in this argument changes the poor fit of this as a filter for the possibility of intelligent life in the universe. As the feasibility is really unknown and even among us humans there are those of us who don’t subscribe to the concept of manifest destiny.
So? It is still far, far less delta v to get from one to the other, for what very little reasons there would be for moving people or materials from one to another.
Much, much smaller. That’s still a whole lot of material.
Not sure how that precludes anything. Mining on mercury does seem to be a natural next step after conquering the low hanging fruit of near earth asteroids.
Are you saying that you are assuming that we will develop new technologies that we don’t even know where to begin with? But you doubt that we will expand existing technologies?
Could you clarify this, it doesn’t make sense to me.
Not sure what your point is here. Why does it matter what microwave transmission capabilities are, when I’ve not mentioned anything about microwave transmission or even any sort of energy transmission in any of my posts?
Maybe some very small amount of resources would be devoted to producing energy for use on earth, but that vast majority would be going into manufacturing and mining endeavors.
Now I know that you are not actually paying attention to anything that I have posted, as I have said that my opinion is that we are the first. Your point that you accuse me of ignoring is exactly the point I am trying to make.
I’ve said essentially the same thing in this very thread. Not sure how you think that this refutes anything.
What do you mean without evidence? You are saying that there is no evidence that life grows and fills every niche? Are you saying that there is no evidence that humanity grows and fills every niche?
You banking on new physics being discovered that requires no energy and resource inputs is an interesting syfy idea, but it is not one that is in line with what we know about how the universe works. You ask me for evidence that life grows, I ask you for any evidence at all that these breakthroughs in new understandings of physics will happen.
I have not mentioned “autonomous self replicating robots”, so I’m not sure what your point is here. But I will point out that the mining, refining, and manufacturing industries have embraced automation. These industries employ a fraction of the employees that they did decades ago, and produce an order of magnitude more. This trend continues.
Are you asking me these questions now, or are you saying that these are unanswerable questions? I really don’t get what you are trying to get at here.
Two things.
First, that’s only true for the small low powered satellites and probes we have sent out. As you probably know, as temperature increases, so does the radiative heat dissipation. So, when you have a small low powered satellite based on solar or a small RTG, then you need about that to radiate the waste heat. If you have a larger, large scale solar or nuclear powered system, the rejected heat will be at a much higher temperature, and therefore, give much higher radiative losses. If need be, heat pumps can also be used to increase the temperature of the radiators, until they are glowing a nice cherry red.
Second, so, we’ll big need radiators. It’s not like there’s any real space restrictions to them.
I really don’t know what that first sentence means, but as far as gear, well, that’s why we are building these industries, and cooling has already been addressed.
It seems that this argument could be a good argument to explain why we don’t have mining and refining on earth as well.
What types of life are we talking about? Single celled organisms? Sure. We are developing telescopes that may be able to take spectroscopic data of planets around other stars, and if we see interesting things in those atmospheres, that may indicate some form of life. I have not in anyway dismissed any of that, much less by claiming that humanity may grow and expand and use all available resources as we have done throughout our history.
Not handwaving anything, except maybe pushing through some of this straw.
You don’t think that Jeff Bezos or any of the companies that are looking into extracting valuable materials from asteroids are planning on incremental steps and improvements, for personal economic benefit, with societal goal as at most a distant factor? You think that they are just going to go out and build a dyson sphere as their first step?
Who says that more than a fraction of this power would be going to earth?
The immediate return of increased standards of living due to a decrease in scarcity of energy and resources needed to fulfill our needs and wants.
As it is, I have no direct descendants, and it is unlikely that I will. So the accusation that it is to protect my linage is more than a bit off the mark. As far as the lineage of humanity, well, we do seem to like to keep the species going. Your argument could be used against anyone doing anything at all to perpetuate or improve the species and it’s conditions.
I’m not sure what your point is in how I phrased my argument. Part of my argument was that having more resources means that we have more carrying capacity, which means more people, which means more advancements in different perspectives and thoughts. Not sure what “these” auto replicating robots are, unless they are the ones made of straw. I’ve said nothing at all about auto replicating robots, they are not necessary, and while I don’t know that I would agree that it is immoral, it could be a bit dangerous if self replicating machines could be made and were done poorly.
And as far as vanity, I hadn’t brought that up, but you have a good point. We are very vain, and do do things for vain purposes. Here’s an example ofbillions of dollars being spent so that we can watch a few score men run into each other a few hours a week, 8 weeks a year. I’ve been talking about the practicalities of such projects, but you are correct in that we will do things not because they are practical, but because we just want to leave a mark.
Note that the population that died off was the population that stayed home, not the population that traveled. I don’t know where you are going with the plague and stuff language, as I have never advocated for any sort of interstellar travel, just expansion. If you are that concerned that some random space plague could wipe us out, then you should be concerned about all the other life in the solar system as it is.
As it is quite rare for diseases to jump between organisms that evolved on the same planet, and that requires those organisms to spend quite a bit of time in close proximity so that the bug can evolve to be compatible with both hosts, while space plagues are a staple of some syfy thrillers, they are actually quite unlikely in real life.
As I said before, you could have intelligent life that never become space faring. There could be many reasons why a species becomes intelligent, but never develops space travel. We were intelligent hominids for at least a hundred thousand years. If you brought an infant from our distant ancestors, and raised it today, there’d be little difference. We could have maintained that level of technology, of having barely mastered fire, until we went extinct. There could be intelligent aquatic life, that could never develop something as simple as writing, much less metal forging and high tech industries. There could be high tech civilizations on worlds just like our own, except 4x the gravity, where getting anything into space requires magnitudes more effort.
But, as it comes to detecting space faring civilizations, seeing or not seeing structures that space faring species would build does act as a reasonable filter on whether or not there are space faring species.
It is only a paradox in that people insist that it is when they attempt to disprove it. I have not said it is. The question that fermi asked “where is everybody?” is not a paradox, it is a question.
Just as the twin’s paradox in relativity isn’t really a paradox, either.
It is a paradox in that at first glance, it seems to be contradictory, but, there are no actual paradoxes, just limited understanding. Pointing to where paradoxes seem to appear points to gaps in our understanding, and encourages people to consider them. They do not mean that the universe doesn’t make sense.
So, forget paradox, as that is more just there to point out that it is a complicated question to be considered, rather than a break in the laws of physics or logic, and just concentrate on the question that other people then decided to label as a paradox.
The problem that I have always found, in designing and illustrating Dyson Spheres, is that they require lots of energy to build, so you need to have already created one in order to gather enough energy to build it. It is a kind of paradox. You would need to start small, and gradually increase the amount of planetary engineering over time. Probably most civilisations simply say -’ ‘no, wait; we’ve got enough energy now. Building more collectors would be superfluous’.
Except that Dyson Spheres should make pretty formidable weapons. The potential ability to focus all of a star’s power onto a distant target might appeal to some of the more paranoid alien types. Maybe that’s why we don’t see them - as soon as a civilisation starts building them, they destroy themselves in an orgy of long-distance destruction.
