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Comment Re:core point (Score 1) 175

Such a lifeform could easily engage in interstellar travel, even with the hundreds and thousands of years it takes.

Most sci-fi fans vastly underestimate the difficulty of even getting remotely close to the speed of light. The last, optimized, peer-reviewed design for a pure antimatter-driven ship that I saw - the highest performance you're going to get without beamed power, and beamed power suffers from range problems among others - was to reach about 0,4c. That's pure anitmatter, which vastly outperforms fusion and fission. Making antimatter inherently means turning mass to energy, wherein a very tiny fraction will condense out as antiprotons, which you can then trap. So you're taking E=mc^2, reversing it, and then taking only a tiny fraction of even that. Actually mass producing the vast amounts of antimatter needed for such starships would take a civilization advanced to Type 2 scale. It's nice to fantasize that the universe is full of Type 2 and Type 3 civilizations, but that's a huge thing to posit.

It's also easy to posit generation ships. But as the saying goes, shit happens. The longer you're in transit, the more likely that is to happen. Which means you have to make your ship vastly larger, to be increasingly redundant, parts in one part increasingly isolated from others, much larger crews than just the minimum skeleton crew needed to populate a planet, etc. Unless all you're sending are artificial wombs and eggs. But then you're back to my initial posit, that such information could be transmitted to an alien species directly at the speed of light.

Comment Re:Maybe (Score 1) 94

Indeed. VW did very egregious cheating, deliberately detecting tests and then optimizing for them. It sounds like these others are not engaging a "test mode"; but have optimized themselves for conditions that are tested for (at the expense of power and fuel efficiency) while optimized themselves for power and fuel efficiency in conditions that aren't tested for. Not as egregious, but still clearly problematic. There's clearly gaping holes in the system.

It also puts to lie this massive increase in diesel cleanliness over the years. It's improved, no question, but not nearly as much as has been marketed, particularly in smaller, cheaper vehicles. The same old choice remains: you can get a ~15% increase in fuel efficiency by mass (~30% by volume), and thus ~15% reduction in CO2 emissions, by going with a diesel, but it'll come at the cost of a more expensive engine (has to be built stronger to handle the higher compression, all issues of additional pollution control systems aside) and will kick out more health-impacting pollutants. And it just comes down to chemistry: if you burn fuel in air at hotter temperatures and/or higher pressures, you favor the production of chemicals like NOx - high temperatures and pressures make nitrogen more reactive. And you're going to kick out more PM for similar reasons. The higher temperatures and pressures help with CO and unburned hydrocarbons (they favor more complete combustion), but the scale of the added NOx and PM problems are much greater.

Contrary to what they've been pretending, a major way that car manufacturers appear to have been reducing NOx emissions in diesels is simply by burning their fuel cooler / less efficiently in conditions that are being tested for, and hotter the rest of the time to keep their performance and efficiency numbers up.

Comment Re: ZFS is nice... (Score 1) 267

But it's combined by the user at runtime, not by canocal. The GPL allows an end users to do this.

This is a way that people kid themselves about the GPL. If the user were really porting ZFS on their own, combining the work and never distributing it, that would work. But the user isn't combining it. The Ubuntu developer is creating instructions which explicitly load the driver into the kernel. These instructions are either a link script that references the kernel, or a pre-linked dynamic module. Creating those instructions and distributing them to the user is tantamount to performing the act on the user's system, under your control rather than the user's.

To show this with an analogy, suppose you placed a bomb in the user's system which would go off when they loaded the ZFS module. But Judge, you might say, I am innocent because the victim is actually the person who set off the bomb. All I did was distribute a harmless unexploded bomb.

So, it's clear that you can perform actions that have effects later in time and at a different place that are your action rather than the user's. That is what building a dynamic module or linking scripts does.

There is also the problem that the pieces, Linux and ZFS, are probably distributed together. There is specific language in the GPL to catch that.

A lot of people don't realize what they get charged with when they violate the GPL (or any license). They don't get charged with violating the license terms. They are charged with copyright infringement, and their defense is that they have a license. So, the defense has to prove that they were in conformance with every license term.

This is another situation where I would have a pretty easy time making the programmer look bad when they are deposed.

Comment Re:Isn't it widely accepted... (Score 2) 130

It's not that simple. Mercury also has a magnetic field. Which is a real head-scratcher, as it's even smaller than Mars.

Internal planetary dynamics are complicated. To get a dynamo you need fluid flow. But whether something is liquid or solid depends on both temperature and pressure - temperature increasing melt, pressure decreasing it. So there's a very complicated interplay.

Comment Re:Isn't it widely accepted... (Score 3, Informative) 130

Very little energy reaches the Venusian surface - Venus's albedo is twice that of Earth's, so most light gets reflected from the cloud deck, and what does enter gets quickly absorbed in the clouds and thick atmosphere. Also, the crust is not what drives a dynamo, the core does. Nuclear decay is what drives terrestrial planet cores, not solar input.

Also I don't know what you mean by "rapid crust recycling", unless you mean Venus's global resurfacing events. But those only happen once every several hundred million years. And they take about 100 million years to complete, they're not rapid.

Comment Isn't it widely accepted... (Score 4, Interesting) 130

... that because of Mars' small size, it cooled faster, thus freezing its outer core and shutting down its dynamo? Isn't Venus the far greater mystery? Nearly the same size as Earth, yet no magnetic field and what appears to be occasional whole-crust overturn rather than plate tectonics? Isn't that the one we need to solve?

Comment Re:core point (Score 1) 175

I agree. The field of extraterrestrial linguistics has seriously advanced beyond then, thankfully, with communications systems based on logic system, and even a transmittable operating system that explains how it should be run (inputs, outputs, etc), enabling one to send interactive programs along with it.

It's funny, but there's a concept I've never seen before in science fiction: that of multiple alien species living amongst each other, but whose homeworlds are vast cosmic distances apart and who have never gotten anywhere close to each other due to the difficulties of approaching relativistic velocities in spacetravel. How? Bit by bit we understand more of "what makes us tick". Not just how DNA codes for proteins, but the whole complex interplay of these proteins in keeping a cell operating. We now understand how to turn skin cells to pluripotent stem cells, stem cells to primordial germ cells, and are approaching being able to turn them into eggs and sperm without having to implant them in testes or ovaries. Some day, probably somewhere between several decades to a century or so from now, we may well have developed the ability to create a fertilized egg completely from scratch - including all of the organelles necessary to keep it alive - and an artificial womb to carry it in. Once one has transmitted the means to convey information and technology, plans can be transmitted (ala Contact, but with technology for biological creation, not communication). One could send to another world every last step needed to create and nurture a human being in-situ, along with a interactive computerized childrearing "system" for the child's early years, along with a discussion of exactly what is being done at each stage. And other species could do this as well in their transmissions to us.

Of course, if the "singularity" people are right, one could just transmit a sentient program to other worlds and be done with it far simpler. Either way, whether anything gets done with a signal depends on whether they're 1) actually out there, 2) close enough, 3) receive the message, 4) detect it, 5) recognize it as carrying information from sentient beings, 6) decipher it, 7) and perhaps most importantly, decide whether they want to actually risk trusting this transmission from an alien world. Lots of "ifs", to say the least.

Comment Re:core point (Score 1) 175

To be able to hold a pointing orientation in space, one has to be able to understand 2D. To be able to understand changing positions in space, one has to be able to understand 3D. To interact with physical objects, they must have some method to perceive their shape. If they're interacting with spacecraft, they have to be able to do some pretty damned precise things in regards to all three of these things The methods used to be able to do these things may be alien to us, but they have to be able to understand them in some sort of form. They essentially have to be able to perceive the voyager plates, perceive that there's information of some form on there, and have the mental wherewithal to convert it into whatever coordinate space / representation system their minds use, and to begin to make deductions about its meaning.

They could reach the wrong conclusions. But if they're spacefaring, they have to at least be capable of advanced reasoning, so they're going to have a shot at it.

Comment Re:...uhh (Score 5, Interesting) 175

Every signal that we have sent out requires them to be visually oriented. Do you think the TV signals we beam into space will make any sense to beings that communicate ultrasonically? An encoded 2D image interlaced with alternate lines 30 times a second won't be of much use to intelligent vampire bats.

Okay, first off...

1) Vampire bats do not work that way.

2) Humans take information that our senses can't perceive all the time and turn in into forms that we can. That's what false-color images and the like are.

3) A species that can pick up the signal (as the GP posited) is most definitely able to transform signals between mediums. It's pretty much a fundamental part of any receiver technology - you take a propagating signal, turn it into data, then turn the data into a form that you can perceive.

Obviously no species is going to inherently have the recipe for demodulating the signal just handed to them - they'll have to figure it out, even if their senses are precisely the same as ours. They'll have to recognize, "hey there's a signal here, and by its pattern it doesn't appear to be naturally generated and seems to be storing data in some manner". They'll then have to reverse engineer how to pull the data out of the signal. Then they'll have to figure out how the data is structured (probably the hardest part, esp. with modern compressed digital formats). All of these apply to all beings. But once you've figured all of that out, turning it into a form that you can perceive is the easy part.

Say there's a species with no vision that can only experiences the world through ultrasound echolocation, as in what you probably intended to be your example? Once you understand that the signal is, say, periodic frames representing an array of triplet values (what we know to be RGB) and know how to decode it to that, the species may play it back by, say, an "ultrasound screen" that creates the perception of a 3-dimensional surface, with the height representing pixel intensity. Maybe they might combine all three RGB values into one height, maybe they might present them as side by side heightfields, maybe they might use one value to represent height, another to represent surface roughness, another to represent sound absorptive properties of the surface, or somesuch. They'll pick whatever is most convenient for them.

I'm not going to humour your "liquid methane temperature" communication concept because that's far too low bandwidth for a sentient species to practically use. Pheromones also. And "interference patterns of UV radiation", that depends on what you mean by "interference patterns" - you're either talking about a UV equivalent of echolocation, as above, or just visible data shifted into the UV, which is just a frequency shift on the RGB image into their visual range. We as humans do frequency shifts of astronomical data all the time, that's what every image made from a UV, X-ray, IR, radio, etc telescope is.

For any species to be able to get to the phase of being able to receive and demodulate communications, it must have at least the concept and ability to perceive 2D orientation (if not 3D), because it has to be able to align receivers with the right patch of sky. That perception can be of some unthinkably bizarre form by our standards, but it has to exist. Whatever perception of 2D it has, 2d images can be presented in that form.

Your Pi/Tau example is clearly pointless. We as humans clearly know of both constants. Sure, Pi "stands out" more to us at first glance, but if we received something that appeared to be of non-natural origin, you really think nobody would notice if the data was Tau?

Circles are no more "rare in water" than on land. The cross section of a sphere is a circle. What do you think bubbles are? Rounded rocks? Round sea life? Heck, lava underwater, unlike on land, tends to produce round structures called pillow lava. And again, if this to the point of being able to isolate faint radio transmissions from the cosmos and recognize natural from manmade, then it's familiar with all sorts of other concepts - stars, planets, moons, orbits, and countless other macroscopic round things, as well as microscopic / subatomic round things, both 2d (circles) and 3d (spheres). And how exactly are their mathematicians (which they fundamentally must have to be able to be able to demodulate these signals) not figuring out what shape has the least surface to area (or in 3d, surface area to volume) ratios? How are they dealing with radio transmissions without understanding sines/cosines and the like?

There is no such thing as "a constant that describes the relationship of the volume of a sphere to its radius/diameter". To its radius/diameter cubed, yes, but not its radius/diameter. And you really think that mathematicians trying to figure out a transmission from another world wouldn't be able to figure out that a number was 3/4 Pi? Seriously?

In your last example (gravity waves), you've switched to something entirely else entirely. You're responding to a post based on the premise " If they have the ability to pick up the signal". So why are you talking about a situation where they can't pick up the signal because they communicate by gravity waves and we don't? And seriously, if they can manage something as difficult as gravity wave communication, radio wave communication is going to be laughably simple to them.

Comment Re:ZFS is nice... (Score 1) 267

Uh, that doesn't work. The problem is that doing exactly what you've written down is contriving to avoid your copyright responsibility by deliberately creating a structure in someone else's work which you believe would be a copyright insulator. If you went ahead and did this (I'm not saying that you personally would be the one at Ubuntu to do so), I'd love to be there when you are deposed. Part of my business is to feed attorneys questions when they cross-examine you. I have in a similar situation made a programmer look really bad, and the parties settled as soon as they saw the deposition and my expert report. See also my comment regarding how Oracle v. Google has changed this issue. You can't count on an API to be a copyright insulator in any context any longer.

"It's like deja vu all over again." -- Yogi Berra