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SeptimusHeap from Switzerland (Edited uphill both ways) Relationship Status: Mu
#2226: Nov 19th 2022 at 6:49:23 AM

It doesn't matter which way you're moving or how fast; any test you can perform will show light to be moving at exactly c in every direction.

Ahem.

"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard Feynman
Fighteer Lost in Space from The Time Vortex (Time Abyss) Relationship Status: TV Tropes ruined my love life
Lost in Space
#2227: Nov 19th 2022 at 6:54:09 AM

That's not a contradiction. The warping of space expressed by general relativity changes the length of the path that light travels through space, but doesn't change its velocity through that space.

Also, light travels at different speeds through different mediums, but that's also not a contradiction; the c we are talking about is the speed of light in a vacuum.

Edited by Fighteer on Nov 19th 2022 at 9:55:41 AM

"It's Occam's Shuriken! If the answer is elusive, never rule out ninjas!"
Mullon Since: Jan, 2001 Relationship Status: And here's to you, Mrs. Robinson
#2228: Nov 19th 2022 at 11:03:53 AM

How close are we to having real life Inspector Gadget limbs?

Never trust anyone who uses "degenerate" as an insult.
Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2229: Nov 19th 2022 at 11:08:57 AM

It's impossible, so it will never happen. Gadget limbs basically use Hammerspace.

Hope shines brightest in the darkest times
Fighteer Lost in Space from The Time Vortex (Time Abyss) Relationship Status: TV Tropes ruined my love life
Lost in Space
#2230: Nov 19th 2022 at 11:13:43 AM

I suppose he could be spontaneously converting energy to mass and back again, but that raises a whole host of other problems.

"It's Occam's Shuriken! If the answer is elusive, never rule out ninjas!"
Protagonist506 from Oregon Since: Dec, 2013 Relationship Status: Chocolate!
#2231: Nov 19th 2022 at 12:03:20 PM

I'd argue something like an "Inspector Gadget Limb" isn't strictly impossible so much as exaggerated by fiction.

Such a limb would be akin to a swiss army knife. Swiss army knives are obviously possible, but they have to work within certain limits. Namely, everything would have to fit within your limb.

I'll note that it's probably more practical to simply carry a bunch of gadgets on your person rather than in your person.

One possible solution would be to invent a sort of 'transforming tool'. For example, a screwdriver that can turn into a hammer or a knife. Such a tool would essentially bypass the need for having too many different types of tool, since it's technically just one.

Leviticus 19:34
Noaqiyeum we must dissent (it/they) from across the gulf of space (Time Abyss) Relationship Status: Arm chopping is not a love language!
Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2233: Nov 19th 2022 at 1:22:21 PM

Oh, I was thinking of the extend-o-limbs. But yeah, the tools, too, would require either Hammerspace or nanotechnology.

Hope shines brightest in the darkest times
Zendervai Since: Oct, 2009
#2234: Nov 19th 2022 at 1:36:29 PM

The question I have is whether or not that kind of robot limb would be a good idea. It uh…directly dovetails into one of the nightmares of modern cyberpunk.

Namely, that to hold a job, you might be forced to get a specific really specialized augmentation…and then you’re permanently shackled to your employer and you better hope they don’t go bankrupt or fire you because then you’re just fucked.

A standard “this replaces your original limb and has a couple extra features” might not necessarily fall into that category, but one full of special features and unique functions absolutely would.

Nanotechnology augmentations would be really cool though.

Edited by Zendervai on Nov 19th 2022 at 4:36:50 AM

Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2235: Nov 19th 2022 at 2:17:21 PM

In such a situation, you could presumably get a new implant by a new employer, or perhaps the state will provide generalized implants for the unemployed, similar to a wheelchair.

Hope shines brightest in the darkest times
Zendervai Since: Oct, 2009
#2236: Nov 19th 2022 at 2:42:24 PM

Being dependent on your employer for part of your actual body to function correctly is a bad thing.

Not to mention that it's incredibly coercive.

"I want a raise."

"Great, we'll fire you, take your arm, and blacklist you, and hire someone who will work for half your wage."

It's one of the ultimate anti-worker's rights moves that could be taken and a lot of companies would happily demand a specific augment that isn't actually that helpful for the job but that would be crippling to go without after the fact in order to permanently break labour movements.

M84 Oh, bother. from Our little blue planet Since: Jun, 2010 Relationship Status: Chocolate!
Oh, bother.
#2237: Nov 19th 2022 at 2:46:57 PM

It's basically a slightly less messy version of hiring Pinkertons to break strikers' limbs.

It'd be even worse if we're talking about a brain implant that upgraded one's intellect or something. That's actually a subplot in Angel. One character ends up getting an implant that makes him an Instant Expert lawyer as part of a deal that gave the main characters control over the evil law firm that was the series' main antagonist. But at some point the implant starts to fail.

The character can't handle going back to what he was before the implant, so he goes to the firm's doctor to fix it. Said doctor agrees to fix it...if he signs for a certain artifact that got stuck in customs. He does. And this leads to tragic consequences.

Edited by M84 on Nov 19th 2022 at 6:51:59 PM

Disgusted, but not surprised
Noaqiyeum we must dissent (it/they) from across the gulf of space (Time Abyss) Relationship Status: Arm chopping is not a love language!
we must dissent (it/they)
#2238: Nov 19th 2022 at 3:00:49 PM

[up][up][up] No, it's entirely realistic that a company would demand employee responsibility for their own augmentation, either as a prerequisite to hiring ("Job requirements: must be certified to operate and maintain a distributed reployer array, able to lift 250 kg with reasonable accommodations, and possess a modular limb attachment that meets industry standards") or as a heavily-encouraged "option" for which they'll generously loan the down payment and will withhold a percentage of your paycheck until it's paid back. Businesses regularly try to push training and experience onto workers that way already.

Those aren't issues with augmentation itself, though, but with the culture adopting it. A distinct but related issue is prosthetic security - you would want to be extremely certain your new mind-machine interface hasn't just attached your body to the Internet of Things.

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Protagonist506 from Oregon Since: Dec, 2013 Relationship Status: Chocolate!
#2239: Nov 19th 2022 at 3:34:01 PM

Personally, I think cyborgs (at least ones with heavy augmentation) will generally be Awesome, but Impractical for some time.

Essentially, a cyborg would be destroying functional and reliable organs for machinery that would tend to be difficult to replace, not necessarily reliable, and will become obsolete.

The biggest issue is that they wouldn't necessarily have much of a practical advantage over externally-worn gear or tools. For example, yes, a cybernetic limb might theoretically be stronger than a human arm. However, would it be stronger than a human in power armor? Or a robotic drone? Or even just a regular forklift?

Let's imagine a non-sapient forklift robot. This machine has several advantages over a cyborg with a cybernetic limb:

  1. You don't need a surgeon to install it or uninstall it.

  2. If it breaks down, that's not as big of an emergency as someone's cybernetic limb shutting down.

  3. It doesn't have to compromise for human biology.

  4. Because of the above two points, it can also afford to be more experimental and cutting-edge. After all, with a cybernetic you have to play it safe, but with a machine like the forklift robot, you have more room to work with.

  5. It's not mutually exclusive with similar machines. With a cybernetic limb you can only fit so many goodies into it. But I can just have two drones purpose-made for different jobs.

Leviticus 19:34
Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2240: Nov 20th 2022 at 2:48:32 AM

Some people are dependent on their employer to have a car or a laptop. Perhaps being dependent on your employer for a cybernetic enhancement will one day be just as normal as having a lease car or a work laptop.

It's also possible people would have a general use cybernetic for personal use, and a work cybernetic for work.

Edited by Redmess on Nov 20th 2022 at 11:59:53 AM

Hope shines brightest in the darkest times
tclittle Professional Forum Ninja from Somewhere Down in Texas Since: Apr, 2010
Professional Forum Ninja
#2241: Nov 22nd 2022 at 6:36:38 AM

A global panel of scientists and government representatives have unanimously agreed to scrap the leap second in Universal Coordinated Time (UTC) starting in 2035.

"We're all paper, we're all scissors, we're all fightin' with our mirrors, scared we'll never find somebody to love."
Zendervai Since: Oct, 2009
#2242: Nov 22nd 2022 at 6:41:10 AM

[up][up] That seems...really odd. I can sort of get the idea, but that seems like it would be extremely difficult on people, psychologically. We're not modular like that and if your body is different from your internal self-image, it can have really negative effects, so switching between multiple cybernetics could very easily set that reaction off.

IMO, I don't think that cybernetics would inherently trigger that, but there would absolutely need to be a psychological adjustment period and rapid switching would cause problems there.

And the difference between being dependent on your employer for a car or a computer and a cybernetic is that one should never be dependent on their employer for their health or parts of their body. (Yes, I think health insurance tied to work is a really bad thing)

SeptimusHeap from Switzerland (Edited uphill both ways) Relationship Status: Mu
#2243: Nov 22nd 2022 at 8:15:34 AM

Cancer across the tree of life: cooperation and cheating in multicellularity TL;DR almost all lifeforms (that have been studied) can get some kind of tumours, although proper metastatizing tumours (i.e cancer in the medical sense) is limited to organisms that don't have cells walls.

Having said that, fasciation - a kind of abnormal growth in plants - is probably biologically a form of tumour.

In its simplest form, a tumour occurs whenever cells in a multicellular organism begin to "cheat" on the rest of the group. Any kind of multicellular anything has to deal with this risk.

"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard Feynman
Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2244: Nov 22nd 2022 at 12:00:37 PM

[up][up] Perhaps you're right, it could be more psychologically involved.

Hope shines brightest in the darkest times
SeptimusHeap from Switzerland (Edited uphill both ways) Relationship Status: Mu
#2245: Nov 23rd 2022 at 12:02:51 PM

So what happens if you increase the tilt of Earth's rotation axis relative to the Sun from its present-day value of about 23 to over 54? The tropics become colder than the polar regions and seasons become much more extreme than today; spring North Africa and Tibet become Antarctica-like while summer Siberia and Canada heat to over 80 degrees centigrade.

"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard Feynman
eagleoftheninth Shop all day, greed is free from a dreamed portrait, imperfect Since: May, 2013 Relationship Status: With my statistically significant other
Shop all day, greed is free
#2246: Nov 25th 2022 at 6:14:02 AM

It's Flat Fuck Friday! If you have any interest in the developing world of 2D materials, then this article from August on Quanta Magazine, while framed as a profile piece on a couple of researchers, is a pretty neat primer on the big picture.

  • So, a lot of materials come in some sort of 3D crystal or strand. For example, graphite looks like this; sodium chloride (aka table salt) looks like this; and aluminium oxide looks like this. Individual atoms or molecules become building blocks, chained by chemical bonds to one another in a repeating 3D pattern that makes up a larger crystal.

  • These structures define everything about the material. They define its material properties — for example, steel is a lot tougher than pure iron because it has little carbon atoms sandwiched between iron atoms in the crystal and resisting the forces that try to make it deform. They define its electronic properties: a material with multiple component elements and physical dislocations is going to have a lot of things obstructing the flow of electrons, limiting its conductivity. The same factors define its optical properties: a material with a lot of space between its atoms and few scattering points is going to let light through better. And so on.

  • As it turned out, some materials can take the shape of a single, 2D layer as well. Remember graphite? Remember how it's made up of layers of carbon atoms in repeating hexagonal rings? Well, turns out that those layers aren't chemically bonded with one another — they're only held together by weak van der Waals force, and you can absolutely peel off individual layers to play around with. That's actually how we discovered graphene, the 2D form of graphite, when a group of researchers in 2004 used Scotch tape to peel off little strips of it just one atom thick. Without the electric fields of the neighbouring layers to slow them down, electrons on a graphene strip can zoom around at incredible speeds, giving the material extreme (though not super-) conductivity.

  • Graphene was only the beginning: new 2D materials soon followed. There's 2D boron nitride, which forms a honeycomb structure like graphene does and can function as a single-layer insulator between slices of other 2D materials — kind of like silicon dioxide slabs on semiconductor chips, if you will. There's molybdenum disulphide, which looks very similar to graphite on the macro level but functions as a 2D semiconductor. This last material actually belongs to a whole family called transition metal dichalcogenides (TMDs), which are made up of repeating blocks of one transition metal atom (in this case molybdenum) and two chalcogen (group 16 element) atoms.

  • TMDs can be formed in a single layer, but they aren't perfectly planar like graphene is — for example, a single layer of molybdenum disulphide looks like this. Which brings us to the complications of working with these materials: when you're doing experiments by stacking single-atom sheets of material on one another, it's easy to for them to simply crumple up or fail to stick. The electrodes you'd use to run electrical currents through them need to be appropriately tiny. Even growing the materials is tricky: just like 3D single crystals (like the electronic-grade silicon in your device's chips), these 2D sheets need to be painstakingly grown atom by atom, by melting the raw materials into liquid and cooling it down at an extremely slow rate.

  • On the upside, though, 2D materials open up entirely new fields. Our current application of electronics revolves around the movement of charge-carrying electrons between atoms, a volatile process that takes a fair bit of space; even as new manufacturing techniques push device sizes down to single-digit nanometres, we're bound to run up against electron quantum tunnelling and other exotic phenomena that start to pop up at very small scales. One way we've been trying to get around this is through the field of "spintronics", which studies how to encode information into the intrinsic spin of electrons without having to move them around (typically using a precisely-applied magnetic field).

  • Graphene has been a lucrative platform for the study of spintronics: as it turned out, its low barrier to electron mobility also makes it easy for electrons to exchange magnetic spin signals between themselves. Which, combined with its extreme thinness, makes it appealing as a potential sort-of "electrode" to affect the spin of other materials (even if we're still working on ways to turn it the right kind of magnetic for that job).

  • Another emerging field is "valleytronics", which looks into electrons' orbital momentum as a way to encode information. Long story short: each electron in a solid occupies a unique energy level. These levels are divided into two bands: the valence band, which covers lower-energy electrons still tied to their atoms; and the conduction band, which covers high-energy electrons that can freely move through the material.
    • In certain 2D materials, at certain orbital momenta, the lowermost levels of the conduction band and the uppermost levels of the valence band can dip into detectable "valleys" — meaning electrons at those momenta can occupy energy levels outside of what's usually found in the material. By manipulating the momenta of electrons in a solid (which can be done with precise applications of electric fields, magnetic fields or polarised light), we can herd those electrons into the "valleys" along the material's energy band and store information that way — again, without having to actually move mobile electrons around, and using very little energy, to boot.

  • Last but not least (for now), 2D materials like graphene can do some pretty wack stuff when you put a layer on top of another and twist it by exactly 1.1º. When you do that, two things happen:
    • The stack forms a repeating "supercell" pattern, called a moiré superlattice.
    • Electrons can tunnel between the two sheets without any additional energy, and start affecting each other's movement (the term of art is "correlation").
  • The whole field of "twistronics" is even newer than the ones above, and we're still only beginning to figure out some of the freaky things that moiré superlattices can do — like conducting electron flow along the edges of the sheet while insulating it across the centre. Scientists are also looking into ways to use the supercells to simulate the interaction between atoms, as well as new ways to construct similar superlattices without the 1.1º twist angle (like by stacking two different types of TMD with differently-sized honeycombs on one another).

One day, we will read his name in the news and cheer.
Fighteer Lost in Space from The Time Vortex (Time Abyss) Relationship Status: TV Tropes ruined my love life
Lost in Space
#2247: Nov 25th 2022 at 7:49:02 AM

Have you ever had the thought, "What is the world's highest egg drop test?" If not, then you aren't Mark Rober, who just published a video that was three years in the making: "Egg Drop From Space". Okay, it's not literally from space, since that's arbitrarily defined as over 100 km, and they don't get that high. But I'm sure it's still some kind of world record.

Here's the setup. You release a high-altitude balloon. Attached to that balloon is a model rocket that can steer your payload to a target landing site and deploy a parachute to land softly. Inside is, of course, an egg. The challenge is to have the egg reach supersonic velocity and still not break when it hits the ground.

Along the way, Mark discovers a couple of things. First, even the best engineers frequently make dumb mistakes. Second, your friends in the Air Force can't help you with this project because you are technically making a precision-guided missile. Third, the real lesson was the friends we made along the way. Wait, no, that can't be right...

Anyway, it's a great watch.

Edited by Fighteer on Nov 25th 2022 at 11:05:28 AM

"It's Occam's Shuriken! If the answer is elusive, never rule out ninjas!"
Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2248: Nov 25th 2022 at 11:12:07 AM

It's very cool. It's also funny that in the end, a beach ball filled with packing foam was just as effective as all the high tech stuff.

Hope shines brightest in the darkest times
PushoverMediaCritic I'm sorry Tien, but I must go all out. from the Italy of America Since: Jul, 2015 Relationship Status: watch?v=dQw4w9WgXcQ
I'm sorry Tien, but I must go all out.
#2249: Nov 29th 2022 at 2:16:08 PM

Why do seals have claws and sea lions don't? You'd think that sea lions would get more use out of having claws, since their flippers are more flexible.

Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#2250: Nov 29th 2022 at 2:26:55 PM

Maybe it lets them grip onto snow better?

Hope shines brightest in the darkest times

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