Got mine plugged in: gonna vacuum later
this post was submitted on 11 May 2024
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Ha ha yup me too! Got one hiding in my closet. $50 and itβs theirs π€£
Isn't that like a 95% loss?
From MSRP, yes. Mine was second hand and has seen better days. One of the older DC07 ones
Okay, so the title is a bit off. They're hunting for partial Dyson spheres using infrared and optical.
I was confused on how they would detect something completely blocking a sun from millions of light-years away.
Even a Dyson sphere, which is technically unlikely anyway, would be possible to spot. You would look for something very bright in the infrared spectrum with almost no light in the visible spectrum. It would also be larger than a normal star of the same energy, but that would be hard to tell given all the other issues.
A partial swarm is easier because it will have variability towards more infrared and then back to a more normal spectrum.
And, of course, all this is speculation until we find a candidate and determine it doesn't have a natural source for that behavior.
Why would there necessarily be strong infrared emissions? Since a Dyson Sphere is meant to harvest all energy produced by a star, any leakage would be unnecessary inefficiency, wouldn't it?
Thermodynamics says that energy can't be destroyed (mass-energy, but generally that won't matter). So after the work of running your stellar civilization is done, you will radiate out waste heat. There is no real way around this without breaking thermodynamics or having a handy black hole to dump all your waste heat into. Therefore, the energy of the star will still be released, but it will be released as infrared.
If you're using the Dyson sphere purely as a power plant and e.g. charge batteries, the thermal radiation will be distributed over the whole area covered by the civilization.
A solar panel, or any other power generator we use, doesn't radiate away all the generated energy either. It's radiated from the point of use.
So you heat habitats, which radiate heat. And run computers, which radiate heat. And move objects around, which radiates heat (among other things). And if you merely absorb energy from your star...it radiates as heat. This is the whole idea of entropy. Unless your lasers are particularly efficient and you use them to beam the energy elsewhere, your Dyson swarm is going to radiate heat equivalent to the energy your star puts out.
You're ignoring my example - what if you charge up batteries at the Dyson sphere, and use the energy anywhere else? There's no physical reason the energy must be used around the Dyson sphere.
So all you need is a perfect charging system. We don't have those, and physics doesn't allow for them. This would be no different than the laser example I gave, and this only makes sense after you have a second Dyson swarm.
Why perfect? As long as the efficiency is high enough, you wouldn't see the sphere itself as very bright, it would be quite dim. Do we know any hard, physical limitations for this, like we do for speed?
I don't think you have any appreciation for just how much energy even a dim star provides. A Kardashev 2 civilization has access to a billion times the energy we (Earth) have, and we only use about 70% of the energy we have access to. Even if you use all that energy, there will still be waste heat. Now you're proposing that this hypothetical civilization has a second star (at least) that it's importing energy from, which means it will be a larger area emitting infrared in their home system, because thermodynamics still has to be obeyed.
And yes, the laws of thermodynamics have to be obeyed. They are as rigid as the speed of light, meaning there might be shortcuts but they are very advanced. To put it in perspective, we are almost capable of starting a Dyson swarm, and we have no options for bypassing the laws of thermodynamics and only have the barest ideas of how to bypass the speed of light.
I donβt think you have any appreciation for just how much energy even a dim star provides. A Kardashev 2 civilization has access to a billion times the energy we (Earth) have, and we only use about 70% of the energy we have access to.
We also have no idea what such large amounts of energy could be practically used for. Just as one possible example, the recent approach for warp drives would consume large amounts of energy - and it would cause the energy to be used over a large area, going against your assumptions. Of course there are many other options, e.g. creating matter from energy.
Even if you use all that energy, there will still be waste heat.
Yes, and as I keep repeating, the waste heat would not necessarily be produced at the location of the Dyson sphere.
Now youβre proposing that this hypothetical civilization has a second star (at least) that itβs importing energy from, which means it will be a larger area emitting infrared in their home system, because thermodynamics still has to be obeyed.
First: why must there necessarily be a second star? They could live inside ships in-between solar systems, which would only need one star to import energy from, and no more. And my whole point is that this would make the Dyson sphere itself much dimmer than you're assuming it to necessarily be.
And yes, the laws of thermodynamics have to be obeyed. They are as rigid as the speed of light, meaning there might be shortcuts but they are very advanced. To put it in perspective, we are almost capable of starting a Dyson swarm, and we have no options for bypassing the laws of thermodynamics and only have the barest ideas of how to bypass the speed of light
You haven't shown that the laws of thermodynamics actually pose limits here. Nothing I'm proposing goes against the laws of thermodynamics.
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Because all that energy contains heat as well, and you'll need to balance the heat from your star along with the energy absorbed.
You're never going to get to 100% efficient conversion, so you'll have to radiate away the heat so your sphere doesn't melt or something.
Dyson swarms are more likely. We even have a tiny one with our satellites using solar power in a heliocentric orbit. (Dyson spheres are basically impossible.) But we could theoretically detect either in infrared since if it doesnβt give off waste heat, itβd all heat up and melt.
That being said, Iβm personally of the opinion this is a waste of time. Not to get all Fermi Paradox but itβs pretty sci fi brained to think any other species out there is as dumb as we are. Space sucks. You die super fast there. Everything had to align just right for Earth to make a bunch of dumb fuck apes willing to strap themselves onto rockets, have a planet small enough that the rocket could even overcome gravity to enter orbit using chemical rockets, and a World War and Cold War to accelerate things.
Time will always be the great filter. Even if we did spot a Dyson swarm, we have no feasible way to contact anything on a practice timescale. Any speck of civilization we detect will be hundreds of thousands of years out of date at best, billions at worst. Life in the universe, imo, is basically guaranteed. If it happened once, it can happen again. Meaningful contact between separately evolved concurrent sapient species? Not likely.
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If it was actually completely enclosing a star that would be impressive. It would also be a bit pointless, since It would result in your spear heating up to stupid temperatures, Which would cause it to glow in the infrared, so you would detect it by that infrared.
Isnβt the idea that the sphere would have a circumference the size of earths orbit? Not sure it would heat up all that much to be noticeable.
As an owner of three private for profit Dyson spheres, I strongly disapprove.
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This feels like trying to determine FTL travel is possible by looking for warp signatures. We don't yet know megastructures are feasable.
Agree this sounds ridiculous, but isnβt this the basic point of science? Propose something is possible, then make predictions and see if you can prove or disprove. The Dyson Sphere idea itself is ridiculous, but to the extent you can detect large scale technology around a star, that would be fantastic. Even better, this is simply a query on existing data. Imagine if they detected intelligent life this way!
Kind of reminds me of the search for Dark Matter. That whole idea sounds so preposterous yet is the best fit for our current knowledge. But we can make predictions based on this. What could all this matter be to fit the theory while remaining undetected so far? Then you can build particle detectors to find them and particle accelerators to explore conditions for causing them. Eventually we should be able to either detect that matter or to rule out enough possibilities for another theory to better fit our knowledge
We don't really know that building a long-term colony on the Moon or Mars is feasible. We assume that it is because there's no obvious reason that it isn't possible other than it being difficult, but that's just a matter of working up to the necessary technology level.
There's nothing inherently problematic in the idea, it's just very big and ambitious. Equally we have no reason to believe that mega structures are not possible, you throw enough resources and science at the problem. FTL on the other hand has real physical restrictions against its existence, we have no reason to believe those restrictions can be overcome.
Dyson spheres are just very very big, no new crazy negative energy, subspace conduits required, just brute force engineering.
True! Long-term travel within the heliosphere is still thwarted due to the radiation of CMEs which require 350cm of concrete for protection. (Our manned trips to the moon were timed during solar minimum, and still had some worrying moments). While a moon base would could be accomplished by putting it underground (or having shelters underground at minimum) it still keeps us from getting to Mars.
Then there's the matter of creating a self-sustained ecology. All of our efforts so far have either died off or required infusions of elements to perpetrate. Also only a matter of time before we work out a configurable system.
But both of these are something like nuclear fusion, in that we know it can actually be done because we have natural examples (even if self-sustaining nuclear fusion only exists in the core of a star, we're pretty sure it happens IRL). We don't have signs of FTL or megastructures that don't collapse into a giant ball of mass. To qualify for a megastructure, we'd simply have to create something that is millions of meters. Our current freestanding structures measure in the hundreds of meters, and we have at most a few kilostructures like the LHC (27KM) which depends a lot on its fixture to the earth.
So yeah, it's a matter of developing the technology, but I suspect there are a lot fewer decades and great filters between when we figure out surviving CMEs in space versus building megastructures in space that don't collapse.
just build me a freaking elevator already
The next step is a launch loop, and even that will require materials with extreme tensile strength that we do not yet have.
Rotating momentum transfer tethers (skyhooks) might be just within the capabilities of our current materials.
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Let's say we detect one in some other galaxy. What then? And how do you reach out to them?
We don't because we can't. We will just observe the thing for science and stuff.
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Well if we find one we have proof of advanced life elsewhere in the universe. That's the most important thing. Reaching out will take millions of years.
Does it roll around and suck up dirt? How does this work?
Kind of, except it is more like wrapped around a star and sucks up light.
Like a duster⦠for light dirt.
You could say: all that light is going to waste without the dyson sphere.
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