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Green Blaze powers addendum: The high jump

February 5, 2014 5 comments

I’ve added a new paragraph to my earlier post “ONLY SUPERHUMAN reader question: Measuring the Green Blaze’s powers,” since I realized there was one aspect of Emerald Blair’s superstrength that I forgot to address, one that occurred to me as a result of watching The Six Million Dollar Man on DVD. Here’s what I added:

It’s occurred to me to wonder: How high could Emry jump? Of course, that depends on the gravity, so let’s assume a 1g baseline. According to my physics textbook, the maximum height of a projectile is proportional to the square of its initial velocity (specifically, the velocity squared times the square of the sine of the launch angle, divided by twice the gravity). So if we use my earlier, very rough assumption that Emry’s speed relative to an unenhanced athlete goes as the square root of her relative strength, that would cancel out the square, and thus jumping height (for the same gravity and angle) would increase linearly with strength. If she’s four times stronger than the strongest human athlete today, then, it follows she could jump roughly four times the world record for the high jump. Except it’s more complicated than that, since we’re dealing with the trajectory of her center of mass. The current world record is 2.45 meters by Javier Sotomayor. But that’s the height of the bar he cleared, not the height of his center of mass. He used a technique called the Fosbury flop, in which the body arcs over the bar in a way that keeps the center of mass below it. So his CoM was probably no more than about 2.15 meters off the ground, give or take. And he was pretty much fully upright when he made the jump. since he’s 1.95 meters tall to start with, and the average man’s CoM height is 0.56 of his total height (or about 1.09 m in this case), that would mean the world-record high jump entailed an increase in center-of-mass altitude of slightly over one meter. So if we assume that Emry is doing more of a “bionic”-style jump, keeping her body vertical and landing on her feet on whatever she’s jumping up to, then she might possibly be able to raise her center of mass up to four meters in Earthlike gravity. Which means she could jump to the roof of a one-story building or clear a typical security fence — comparable to the jumping ability of Steve Austin or Jaime Sommers.

And just a reminder: I’m open to more reader questions about Only Superhuman or my other writing.

We’ve found water on Ceres!

This just in from Space.com:

Water Found on Dwarf Planet Ceres

Astronomers have discovered direct evidence of water on the dwarf planet Ceres in the form of vapor plumes erupting into space, possibly from volcano-like ice geysers on its surface.

Using European Space Agency’s Herschel Space Observatory, scientists detected water vapor escaping from two regions on Ceres, a dwarf planet that is also the largest asteroid in the solar system. The water is likely erupting from icy volcanoes or sublimation of ice into clouds of vapor.

This is big news. It’s a major scientific breakthrough, proof of something that’s only been suspected about Ceres up to now, and it comes a year earlier than I expected, since the Dawn probe won’t reach Ceres until early 2015. It also has important ramifications for our future in space. In Only Superhuman, I established Ceres as the primary source of water and organic molecules for space habitats throughout the Main Asteroid Belt and inner system. This was based on astronomers’ estimates that Ceres might potentially have more fresh water on it than Earth does (since most of ours is salt water). Now we have verification for that, and it confirms (or at least makes it far more likely) that future space colonists and asteroid miners will have access to abundant sources of water without needing to lug it up out of Earth’s gravity well or go clear out to the moons of Jupiter and Saturn.

It’s also nice to get confirmation that what I put in my novel wasn’t wrong. Although it never occurred to me to mention a water-vapor atmosphere or cryovolcanoes in my descriptions of Ceres. Just as well, I suppose, since the volcanoes are unconfirmed. If and when I get to do a sequel, hopefully the timing will be right to work in Dawn’s findings. Hmm, the article says it’s more likely just sublimation, but I’m hoping for icecanoes (to use the Doctor Who term). Those would be cooler to write about. (Literally…)

Categories: My Fiction, Science

ONLY SUPERHUMAN reader question: Measuring the Green Blaze’s powers

December 30, 2013 3 comments

I recently received a few questions about Only Superhuman from Brandt Anderson via a Facebook message, and I thought I’d address them here. Brandt wrote:

I enjoy most super hero novels such as Ex-Heroes, Paranormals, Devil’s Cape, etc., and one of the things that is always forefront on my mind is stats. I like knowing exactly how strong or how fast the super-powered character is. So, I was hoping you wouldn’t mind giving an approximation on how enhanced Emerald Blair is. Her strength, speed, reflexes, senses, healing factor and durability if you don’t mind. Also, I apologize for this amount of nitpicking, would you able to tell me what her superhuman attributes be at without any of the enhancements she has? And lastly, in your world, how strong is the average super-being and what is the normal human level at?

Those are interesting questions, though to be honest, I haven’t really worked out that many of the details. It’s worth thinking about if I get to do further novels, though, so I’ll try to offer some answers.

I did address Emerald Blair’s strength level in the novel when I had Eliot Thorne mention that she could “bench-press a tonne in one gee,” i.e. standard Earth surface gravity. That led me to the following analysis from my novel annotations:

From what I can find, the current world record for an unassisted or “raw” bench press (without the use of a bench shirt, a rigid garment that supports the muscles and augments the amount they can lift) for a woman in Emry’s weight class seems to be held by Vicky Steenrod at 275 lb/125 kg. Assuming Thorne was referring to what Emry could lift raw, that would make her 8 times stronger than Ms. Steenrod, at least where those particular muscles are concerned. And Emry’s training isn’t specialized for powerlifting but is more general, so that would probably make her even stronger overall. Not to mention that Thorne seemed to be talking about her typical performance, not a personal record. So as an adult Troubleshooter, with bionic upgrades on top of her Vanguardian mods, Emry might be at least 10 times the strength of an unenhanced female athlete of her size and build. That may be conservative, given some of what I’ve read about the possibilities of artificial muscle fibers. On the other hand, there are limits to how much stress the organs of even an enhanced body could endure.

By the way, the all-time raw bench-press world record is 323.4 kg by Scot Mendelson, who’s 6’1″ and over twice Emry’s weight. The assisted world record (with a bench shirt) is 487.6 kg by Ryan Kennelly, who’s about the same size and whose unassisted record is much lower. So going by what I figured before, that would make Emry nearly 4 times as strong as the strongest human beings alive today, and that’s without the added assistance her light armor would provide her (though she’d need to add sleeves to her armor to get the full effect). And that’s the lower limit. In any case, given all the bionic enhancements she’s added to her native strength, she might well be the strongest person in Solsys in proportion to her weight class, or at least right up there with the record-holders of her day.

Only Superhuman cover art by Raymond Swanland

Art by Raymond Swanland

According to my character profiles, by the way, Emerald’s height is 168 cm (5’6″) — at least in one gee or thereabouts, since people gain a bit of height in low or microgravity due to their skeletons being less compressed — and her mass is 69 kg (153 lb), which is a bit heavy for her size, but that’s because of the added weight of her bionics and reinforcements, as well as her dense musculature.

So that’s strength. What about speed? Well, I established in Chapter 6 that Javon Moremba, who’s specialized for running, could run at 60 km/h, which is just one and a third times the world record set by Usain Bolt in 2009. I’m not really sure how much it’s possible to increase human running speed without substantially restructuring human anatomy, since we’re already kind of specialized for running by evolution — although we’re specialized more for endurance running than speed, which was how our ancestors were able to be successful hunters and trackers. Javon’s anatomy is altered from the human norm, with atypically long legs and powerful joints and enlarged lungs. Emerald’s proportions are more normal, and her legs aren’t especially long; plus she’s not exactly lean. She’s built more for strength than speed. On the other hand, the athlete I modeled her physique after, tennis star Serena Williams, can be an astonishingly fast mover on the tennis court due to her sheer strength — though not as fast as her leggier sister Venus.

Okay, so we can safely assume that the teenage Emry couldn’t run as fast as Javon. She’s only 84% his height and less of it is legs, so let’s say she has 75% of his stride. I actually have her down as only 72% of his mass, though; I think I based Javon’s statistics on the aforementioned Mr. Bolt. I guess the question is, what’s the comparative ratio of total muscle mass to push with and total body mass to be pushed? I think I’ll avoid any complicated math and just go with visual intuition, which tells me that Emry has proportionally more excess bulk to deal with; but once she’s bionically enhanced, that might compensate.

So let’s say that with just her raw muscle, no cyborg upgrades, she’s got a minimum of 75% of his running speed, which would be equal to Bolt’s world record. But how much do her upgrades boost her strength? Well, we know that she was always strong enough in her adolescent years to match or overpower any man, and judging by those weightlifting figures above, a man’s maximum strength might be something around 2.5 times a woman’s, all else being equal. But many of those men would be mods themselves, so we’d need to up that. Still, I don’t want too much of her strength to be innate, since the bionics should contribute a lot. So let’s say that she started out roughly 3.3 times the normal strength of a woman of her build and had it tripled by her Troubleshooter bionics.

How does that apply to her running speed? This is probably oversimplifying like hell, but it seems to me that if you exert three times the force on the same mass, then by Newton’s second law you get three times the acceleration. Now, for a given distance, the time needed to cover it goes as one over the square root of the acceleration; and the rate is the distance over the time. So that would suggest, unless I’m doing something very wrong, that if she has three times the acceleration for each thrust of her leg muscles pushing her forward, then her speed would be increased by roughly the square root of three, or 1.73. So if her running speed without bionics was 45 km/h, then with bionics it’d be nearly 80 km/h (50 mph). Though she’s probably capable of bursts of even faster speed when she supercharges her nanofiber implants, as we saw when she made her skyscraper jump in Chapter 11. This would make her about 5/6 the typical speed of Steve Austin, the Six Million Dollar Man, and half the top recorded speed of Jaime Sommers, the Bionic Woman. But let’s call that her sprinting speed. For endurance running, she’d probably average out a bit slower — let’s say 64 km/h (40 mph), which translates to a 1.5-minute mile — which would put her at better than two and a half times the female world record for the mile. It would also put her slightly above Javon’s indicated speed, but that was for a Javon who was out of training. (Oh, and keep in mind that this is assuming she’s in a full Earth gravity or close to it.)

There are other ways of measuring speed, though. How fast can she dodge a blow or throw a punch? That gets us into the next question, reflexes. Well, at one point in chapter 16 (p. 284 in the paperback), I say “Her enhanced reflexes made her dodge the shockdart before she was consciously aware of it, but her mind quickly caught up.” So her reaction time is certainly accelerated considerably beyond the norm, so much that it outpaces her conscious thought at times. And while her foot speed is not too much above normal, her dodging speed can be literally faster than a speeding bullet. Well, a speeding dart. If we assume the dart had a speed of around 300 m/s, comparable to an air rifle pellet and close to a 9mm bullet, and if she was maybe 15 meters away from the shooter, that would give her a twentieth of a second to react, or 50 milliseconds. That’s maybe twice the fastest recorded human reaction time for movement, and nearly four times the typical reaction time for a visual stimulus. And that’s just the reaction time she’d need to begin moving to dodge that particular dart. Add in the time it would take to move far enough to miss and she’d have to be even faster. Now, I found a factoid somewhere saying that Usain Bolt moves a foot every 29-odd milliseconds, which is about one centimeter per millisecond, so if we draw on the above comparisons to Bolt’s running speed (which is a horribly rough comparison, but it’s all I’ve got), the Green Blaze might be able to move 1.5-2 cm per millsecond, and her torso is maybe c. 32 cm at its widest point, so to dodge a dart fired at center mass she’d need maybe 8-11 ms. So she’d need to start moving within 40 ms or less, which would be 5 times average human reaction time. Just for a margin of safety and round numbers, let’s say her reaction time is 6 times average and 3 times maximum.

Edited to add: It’s occurred to me to wonder: How high could Emry jump? Of course, that depends on the gravity, so let’s assume a 1g baseline. According to my physics textbook, the maximum height of a projectile is proportional to the square of its initial velocity (specifically, the velocity squared times the square of the sine of the launch angle, divided by twice the gravity). So if we use my earlier, very rough assumption that Emry’s speed relative to an unenhanced athlete goes as the square root of her relative strength, that would cancel out the square, and thus jumping height (for the same gravity and angle) would increase linearly with strength. If she’s four times stronger than the strongest human athlete today, then, it follows she could jump roughly four times the world record for the high jump. Except it’s more complicated than that, since we’re dealing with the trajectory of her center of mass. The current world record is 2.45 meters by Javier Sotomayor. But that’s the height of the bar he cleared, not the height of his center of mass. He used a technique called the Fosbury flop, in which the body arcs over the bar in a way that keeps the center of mass below it. So his CoM was probably no more than about 2.15 meters off the ground, give or take. And he was pretty much fully upright when he made the jump. since he’s 1.95 meters tall to start with, and the average man’s CoM height is 0.56 of his total height (or about 1.09 m in this case), that would mean the world-record high jump entailed an increase in center-of-mass altitude of slightly over one meter. So if we assume that Emry is doing more of a “bionic”-style jump, keeping her body vertical and landing on her feet on whatever she’s jumping up to, then she might possibly be able to raise her center of mass up to four meters in Earthlike gravity. Which means she could jump to the roof of a one-story building or clear a typical security fence — comparable to the jumping ability of Steve Austin or Jaime Sommers.

So let’s move on to senses. We know from Ch. 3 that 13-year-old Emry’s “enhanced vision” let her make out the movements of the townspeople of Greenwood from some distance away, far enough that the curve of the habitat gave her an overhead view. Now, Greenwood is a Bernal sphere meant to simulate a rural environment with farmland and presumably forest. It should have a fairly low population density, and my notes give it a population around 3000 people. If we set the population density at maybe 30 people per square kilometer, that gives a surface area of 100 square km, for a radius of about 5 km and a circumference of 31.4 km. Now, just eyeballing it with a compass-drawn circle and a ruler, I’d say she’d need to be 1.5 to 2 km away to get the kind of raised angle described in the text. Now, being an assiduous researcher, I went out and braved the cold to visit my local overlook park to see if I could spot human figures at anything resembling that range. The farthest I was able to spot a human being was at a place that I estimate was about a mile/1.6 km away, with the park’s elevation, despite being a respectable 300 feet or so higher, too small to add significantly to the distance. But I just saw the faintest speck of movement. The scene indicates that Emry could see enough detail to make out body language and attitude. I’d say her resolution would have to be at least 3-4 times greater than mine (with glasses). Although we’re not talking about bionic eyes with zoom lenses, so it’s probably more a matter of perception of detail. Assuming my prescription is still good enough to give me 20/20 vision in at least one eye (which I probably shouldn’t assume), that would make Emry’s visual acuity something like 20/7 or 20/5 if not better; the acuity limit in the unaided eye is 20/10 to 20/8 according to Wikipedia. (20/n means the ability to see at 20 feet what an average person needs to be n feet away to see.) Hawks are estimated to have 20/2 vision. Emry isn’t specialized for eyesight, so let’s not go to that extreme. Let’s give her a baseline visual acuity of 20/5, say, about twice the human maximum.

So what do her bionics add? For one thing, they broaden her visual spectrum to the infrared. This is apparently something she can turn on and off. Now, it should be remembered that TV and movies tend to misrepresent infrared vision as being able to see through walls. Actually that usually wouldn’t work, since walls are generally designed to insulate, so heat — and thus IR light — doesn’t pass through them easily. And as I said in the book, glass is generally opaque to IR. So this wouldn’t be the equivalent of “x-ray vision,” except when dealing with less well-insulated things like human bodies. It could enable her to read people’s emotional states through their blood flow, though, or to track recent footprints and the like. She also has an inbuilt data buffer that’s shown recording images from her eyes and letting her replay, analyze, and enhance them later, projected on the heads-up display built into her retina. So that might give her sort of a “digital zoom” ability, to enlarge part of a recorded image, but not to increase its resolution beyond what her eyes could detect. And her implants might up her acuity to maybe 20/4.

As for her hearing, I haven’t established anything beyond the fact that it’s better than normal. She can probably hear a somewhat larger dynamic range than most people and has somewhat more sensitivity, but I’m not sure it could be enhanced too much without a substantial alteration to the anatomy of the ears. But she could have bionic auditory sensors that could allow her to amplify sounds further as needed. As for scent, I establish in Ch. 20 that Emry can track by it, though not as well as someone more specialized for the task like Bast or Psyche. So her sense of smell is, again, somewhat above normal but not massively so. Which would enhance her sense of taste accordingly as well. It’s possible she’s a supertaster, like a lot of real-life people. (In fact, looking over the list of foods that supertasters dislike, I think I might be one!) As for her sense of touch, it’s no doubt unusually sensitive, which is why she’s so hedonistic and easily stimulated. Although her pain sense is no doubt diminished in comparison to her other tactile perceptions. I gather that redheads are normally more sensitive to pain than most, but it stands to reason that her nociception would have been somewhat suppressed.

“Healing factor” is a tricky one; I’m not sure how to codify it. But she does have a fast metabolism and thus probably heals a bit faster than normal, and her bionics include a “nanotech immune-boosting and injury repair system,” as stated in her character bio. She can’t heal nearly instantly like Wolverine in the movies, since there would be physical and metabolic limits on how fast repairs could realistically be done, but she could probably heal, at a guess, 2-4 times faster than normal depending on the type of injury and whether she’s able to rest and replenish or has to heal on the run. (That’s complete guesswork, since I’m not sure where to find information on human healing rates, what the recorded maximums are, or what mechanisms could enhance them.) She’s also got an augmented immune system, both inborn and nanotech-enhanced; she’s probably got little or no experience with being sick, though she might be susceptible to a sufficiently potent bioweapon. She has toxin filters to protect her from poisoning and drugs. Alcohol would probably have little effect on her, but if she is a supertaster, she wouldn’t like the taste of it anyway. And it’s not like she needs help relaxing her inhibitions, since she hardly has any to begin with.

Durability, though, is something the Green Blaze has in abundance, thanks to her “dense Vanguardian bone” and the nanofiber reinforcements to her skeleton and skin. She’s not easy to hurt. She takes a good deal of pounding in Only Superhuman, but the only skeletal injury she suffers is a hairline wrist fracture which is compensated for by her nanofiber bracing. She rarely sustains more than cuts, bruises, and strains. She’s not exactly bulletproof — she needs her light armor for that — but there are enough reinforcements around her skull and vital organs that it would take a pretty high-powered rifle to inflict a life-threatening injury. Her skull reinforcements are probably comparable to a military ballistic helmet, so shooting her in the head would probably cause surface bleeding and a moderate concussion at worst, and more likely just make her mad. And of course her light-armor uniform gives even more protection, strength enhancement, and the like. (Note that this is as much a matter of micrometeorite protection as bullet protection.)

One power Brandt didn’t ask about is intelligence. Emerald Blair embraces her physical side more than her intellectual side, but her intelligence is easily at genius level. She’s definitely smarter than I am, since I have plenty of time to figure out the solutions that she comes up with on the fly. She’s far more brilliant than she realizes yet, and when and if she catches on and begins developing that potential, she could be a superbly gifted detective and problem-solver.

Brandt’s final question is, “And lastly, in your world, how strong is the average super-being and what is the normal human level at?” Well, the normal, unmodified human level is the same as it would be in real life, although people living in lower-gravity conditions would be less strong than Earth-dwelling humans. As for mods, I’m not sure there’s such a thing as an average one, since they’ve specialized in diverse directions. Only some are augmented for physical strength, like Vanguardians, many Neogaians, and Mars Martialis… ans… whatever. Honestly, I’m not sure to what extent physical strength would be needed as a human enhancement in Strider civilization. Combat in the future will be mostly the purview of drones and robots, or soldiers in strength-enhancing exoskeletons. So enhancing individual strength would be more a choice than a necessity, probably more likely to be done for athletics than anything else. Still, in a setting like Strider civilization, where mods have embraced superhero lore as a sort of foundational mythology, there would be an element of sports and celebrity to crimefighting or civil defense. More fundamentally, in a culture where human modification is embraced, physical strength could be seen as a desirable “biohack” just for the sense of power it provides. It’s like how some people like high-performance muscle cars even though they don’t need that much power to commute to work. I think in the Vanguardians’ case it was about exploring the limits of the human animal, finding how far we could be augmented in every possible way, both as a matter of scientific curiosity and as a symbolic statement to inspire others to mod themselves — and thumb their noses at Earth’s resistance to such things. The average Vanguardian might be somewhere around Emry’s pre-bionic strength level, maybe 3-3.5 times normal muscle strength for a given build, though they vary widely in their builds. Still, I think that Beltwide, only a certain percentage of mods would be tailored for strength, with others emphasizing endurance, senses, reaction time, intelligence, adaptation to particular environments, etc. (on top of the radiation resistance that everyone living in space would need).

So, to sum up the Green Blaze’s powers:

  • Strength: c. 10x normal for a woman of her build or 4x baseline-human maximum
  • Speed: up to 80 km/h (50 mph) in c. 1g environment
  • Reaction time: c. 6x average or 3x human maximum
  • Vision: c. 20/4 visual acuity, infrared vision, visual recording and enhancement
  • Other senses: Moderately above human maximum range and sensitivity
  • Healing: Somewhat accelerated healing and cellular repair; very strong immune system and toxin resistance
  • Durability: Considerable resistance to abrasion, contusion, laceration, and broken bones; bullet resistance comparable to a human in moderate body armor
  • Intelligence: Genius-level but underdeveloped

Note, however, that these are her innate power levels, not counting the further enhancements her light armor would provide to her strength, durability, and speed. But figuring those out would be a whole other essay.

Wow, I got a pretty long essay out of this. It was fun, and it could be useful for future adventures, hopefully.

So I’ll open the door. If anyone has further questions about Only Superhuman that haven’t been addressed already on my website, or more generally about my work, feel free to post them in the comments or on Facebook. Easy questions asked in the comments will probably be answered there, while more involved questions may spawn more essays. We’ll see how it goes.

Musings on quantum gravity

Recently I came across this article about an experiment to reconcile quantum physics with gravity, the one fundamental force that hasn’t yet been explained in quantum terms:

New Experiments to Pit Quantum Mechanics Against General Relativity

The problem with reconciling gravity (which is explained by Einstein’s General Theory of Relativity) and quantum physics is that they seem to follow incompatible laws. Quantum particles can exist in superpositions of more than one state at a time, while gravitational phenomena remain resolutely “classical,” displaying only one state. Our modern interpretation suggests that what we observe as classical physics is actually the result of the quantum states of interacting particles correlating with each other. A particle may be in multiple states at once, but everything it interacts with — including a measuring device or the human observer reading its output — becomes correlated with only one of those states, and thus the whole ensemble behaves classically. This “decoherence” effect makes it hard to detect quantum superpositions in any macroscopic ensemble, like, say, a mass large enough to have a measurable gravitational effect. Thus it’s hard to see quantum effects in gravitational interactions. As the article puts it:

At the quantum scale, rather than being “here” or “there” as balls tend to be, elementary particles have a certain probability of existing in each of the locations. These probabilities are like the peaks of a wave that often extends through space. When a photon encounters two adjacent slits on a screen, for example, it has a 50-50 chance of passing through either of them. The probability peaks associated with its two paths meet on the far side of the screen, creating interference fringes of light and dark. These fringes prove that the photon existed in a superposition of both trajectories.

But quantum superpositions are delicate. The moment a particle in a superposition interacts with the environment, it appears to collapse into a definite state of “here” or “there.” Modern theory and experiments suggest that this effect, called environmental decoherence, occurs because the superposition leaks out and envelops whatever the particle encountered. Once leaked, the superposition quickly expands to include the physicist trying to study it, or the engineer attempting to harness it to build a quantum computer. From the inside, only one of the many superimposed versions of reality is perceptible.

A single photon is easy to keep in a superposition. Massive objects like a ball on a spring, however, “become exponentially sensitive to environmental disturbances,” explained Gerard Milburn, director of the Center for Engineered Quantum Systems at the University of Queensland in Australia. “The chances of any one of their particles getting disturbed by a random kick from the environment is extremely high.”

The article is about devising an experiment to get around this and observe a superposition (potentially) in a “ball on a spring” type of apparatus. What interests me, though, is a more abstract discussion toward the end of the article.

Inspired by the possibility of experimental tests, Milburn and other theorists are expanding on Diósi and Penrose’s basic idea. In a July paper in Physical Review Letters, Blencowe derived an equation for the rate of gravitational decoherence by modeling gravity as a kind of ambient radiation. His equation contains a quantity called the Planck energy, which equals the mass of the smallest possible black hole. “When we see the Planck energy we think quantum gravity,” he said. “So it may be that this calculation is touching on elements of this undiscovered theory of quantum gravity, and if we had one, it would show us that gravity is fundamentally different than other forms of decoherence.”

Stamp is developing what he calls a “correlated path theory” of quantum gravity that pinpoints a possible mathematical mechanism for gravitational decoherence. In traditional quantum mechanics, probabilities of future outcomes are calculated by independently summing the various paths a particle can take, such as its simultaneous trajectories through both slits on a screen. Stamp found that when gravity is included in the calculations, the paths connect. “Gravity basically is the interaction that allows communication between the different paths,” he said. The correlation between paths results once more in decoherence. “No adjustable parameters,” he said. “No wiggle room. These predictions are absolutely definite.”

Now, this got me thinking. Every particle with mass interacts gravitationally with every other particle with mass, so there would be no way to completely isolate them from interacting. For that matter, gravity affects light too. So if gravity is an irreducible “background noise” that prevents stable superpositions, that would explain why quantum effects don’t seem to manifest with gravitational phenomena.

And that does sort of reconcile the two. The decoherence model, that classical states are what we get when quantum states interact and correlate with each other, basically means that classical physics is simply a subset of quantum physics, the behavior of quantum particles that are in a correlated state. So the “classical” behavior of gravity would also be a subset of quantum physics — meaning that relativistic gravity is quantum gravity already, in a manner of speaking. We just didn’t realize they were two aspects of the same overarching whole.

Now, this reminds me of another thing I heard about once, a theory that gravity didn’t really exist. It might have been the entropic gravity theory of Erik Verlinde, which states that gravity is, more or less, just a statistical artifact of particles tending toward maximum entropy. Now, what I recall reading somewhere, though I’m not finding a source for it today, is that this — or whatever similar theory I’m recalling — means that particles tend toward the most probable quantum state. And statistically speaking, for any particle in an ensemble, its most probable position is toward the center of that ensemble, i.e. the center of mass. So I had the thought that maybe what we perceive as gravity is more just some sort of probability pressure as particles tend toward their most likely states.

Now, if Stamp’s theory is right, then Verlinde’s is wrong; there must be an actual force of gravity, or rather, an interaction that correlates the paths of different particles. But it occurs to me that there may be some basis to the probabilistic view of gravity if we look at it more as a quantum correlation than an attraction. To explain my thinking, we have to bring in another idea I’ve talked about before on this blog, quantum Darwinism. The idea there is that the way decoherence works is that the various states of a quantum particle “compete” as they spread out through interaction with other particles, and it’s the more robust, stable states that prevail. Now, what I’m thinking is that as a rule, the most stable states would be the most probable ones. And again, those would tend to be the positions closest to the center of mass, or as close as feasible when competing with other particles.

So if we look at gravitation not as an attractive force per se, but as a sort of “correlational field” that promotes interaction/entanglement among quantum particles, then we can still get its attractive effect arising as a side effect of the decoherence of the correlated particles into their most probable states. Thus, gravity does exist, but its attractive effect is fundamentally a quantum phenomenon. So you have quantum gravity after all.

But how to reconcile this with the geometric view of General Relativity, that gravity is actually a manifestation of the effect that mass and energy have on the topology of spacetime? Well, that apparent topology, that spatial relationship between objects and their motions, could be seen as a manifestation of the probabilistic relationships among their position and movement states. I.e. a particle follows a certain path within a gravitational field because that’s the most probable path for it to take in the context of its correlation with other particles. Even extreme spacetime geometries like wormholes or warp fields could be explained in this way; an object could pass through a wormhole and show up in a distant part of space because the distribution of mass and energy that creates the wormhole produces a probability distribution that means the object is most likely to be somewhere else in space. Which is analogous to the quantum tunneling that results because the peak of a particle’s probability distribution shifts to the other side of a potential barrier. And for that matter, it has often been conjectured that quantum entanglement between correlated particles could be caused by microscopic wormholes linking them. Maybe it’s the other way around: wormholes are just quantum tunneling effects.

One other thought I’ve had that has a science-fictional impact: if gravitation is a “correlational quantum field” that helps the most probable state propagate out through the universe, that might argue against the Many-Worlds Interpretation of quantum decoherence. After all, gravity is kind of universal in its effect, and the correlation it creates produces what we see as classical physics, a singular state. It could be that coherent superpositions would only happen on very small, microscopic scales, and quantum Darwinism and gravitational correlation would cause a single consensus state to dominate on a larger scale. So instead of the whole macroscopic realm splitting into multiple reality-states (timelines), it could be that such splitting is only possible on the very small scale, and maybe the simmering of microscale alternate realities is what we observe as the quantum foam. It could be that the MWI is a consequence of an incomplete quantum theory that doesn’t include gravity, and once you fold in gravity as a correlating effect, it imposes a single quantum reality on the macroscopic universe.

Which would be kind of a bummer from an SF perspective, since alternate realities are useful story concepts. I’d just about come around to believing that at least some alternate realities might be stable enough to spread macroscopically, as I explained in my quantum Darwinism essay linked above. Now, I’m not so sure. The “background noise” effect of gravity might swamp any stable superpositions before they could spread macroscopically and create divergent timelines.

However, these thoughts might be applicable to future writings in my Hub universe (and as I’ve discussed before, I’ve already given up on the idea of trying to reconcile that with my other universes as alternate timelines). The Hub is a point at the center of mass of the greater galaxy — i.e. the system that includes the Milky Way proper, its satellite galaxies, and its dark-matter halo — that allows instantaneous travel to any point within that halo. I hadn’t really worked out how it did so, but maybe this quantum-gravity idea provides an answer. If gravity is quantum correlation, and all particles’ probability distributions tend toward the center of mass, then maybe the center of mass is the one point that allows quantum tunneling to the position of every other particle. Or something like that. It also provides some insight into the key McGuffin of the series, the fact that nobody can predict the relationship between Hub vectors (the angle and velocity at which the Hub is entered) and arrival destinations, meaning that finding new destinations must be a matter of trial and error. If the Hub works through quantum gravity and correlation with all the masses within the halo, then predicting vectors would require a complete, exact measurement of the quantum state of every particle within the halo, and that would be prohibitively difficult. It’s analogous to how quantum theory says that every event in the universe is already part of its wave equation, but we can’t perfectly predict the future because we’d need to know the entire equation, the behavior of every single particle, and that would take an eternity to measure. So it’s something that’s theoretically deterministic but functionally impossible to determine. The same could be true of Hub vectors.

Although… we’re only talking about one galaxy’s worth of particles, which is a tiny fraction of the whole universe. So maybe it’s not completely impossible…

Anyway, those are the musings I’ve had while lying awake in bed over the past couple of early mornings, so maybe they don’t make much sense. But I think they’re interesting.

Realism in space: EUROPA REPORT and GRAVITY (spoiler reviews)

November 12, 2013 10 comments

In the past few days I’ve seen two recent movies that took an unusually realistic approach to portraying spaceflight: Sebastián Cordero’s Europa Report (which I watched on my computer via Netflix) and Alfonso Cuarón’s Gravity (which I watched in the theater). It’s very rare to get two movies in such close succession that make an attempt to portray space realistically, and I hope it’s the beginning of a trend. Although both movies did compromise their realism in different ways.

Europa Report is a “found-footage” movie presented as a documentary about the first crewed expedition to Jupiter’s moon Europa to investigate hints of life. It’s rare among such movies in that not only is the found-footage format well-justified and plausibly presented, but it’s actually thematically important to the film. On the surface, the plot follows the beats of a fairly standard horror movie: characters come to an unfamiliar place, start to suspect there’s something out there in the dark, and fall prey to something unseen one by one. But what’s fascinating about it is that it doesn’t feel like horror, because these characters want to be there, are willing to risk or sacrifice their lives for the sake of knowledge, and see the discovery of something unknown in the dark as a triumph rather than a terror. And that elevates it above the formula it superficially follows. It’s really a nifty work of science fiction in that it celebrates the importance of the scientific process itself, and the value of human exploration in space even when it comes at the cost of human lives.

The depiction of the ship, its flight, the onboard procedures, and the behavior of the astronauts is all handled very believably, with a well-designed and realistic spaceship relying on rotation to create artificial gravity. The actors, including Sharlto Copley, Daniel Wu, Anamaria Marinca, Christian Camargo, House‘s Karolina Wydra, and Mission: Impossible — Ghost Protocol‘s Michael Nyqvist, are effectively naturalistic and nuanced. The film’s low budget means they can only manage a limited number of microgravity or spacewalking shots, but what we get is reasonably believable. I do have some quibbles about procedures, though, like the lack of spacesuit maneuvering units during the spacewalk, and the decision later on Europa to send one crewperson out on the surface alone without backup. Really, a lot of the bad things that happened seemed to be avoidable. But I’m willing to excuse it since this was portrayed as a private space venture and the first of its kind. Now, I’m a big supporter of private enterprise getting into the space business, since history shows that development and settlement of a frontier doesn’t really take off until private enterprise gets involved and starts making a profit from it. And I’m sure that private space ventures in real life take every safety precaution they can. But for the sake of the fiction, it’s plausible that a novice organization might let a few safety procedures slide here and there.

The one thing about the film that really bugged me is one that’s pervasive in film and TV set in space and largely unavoidable: namely, once the crew landed on Europa, they were moving around in what was clearly full Earth gravity. Europa’s gravity is 13.4 percent of Earth’s, a few percent less than the Moon’s gravity, so they should’ve been moving around like the Apollo astronauts. Unfortunately, it seems to be much harder for Hollywood to simulate low gravity than microgravity. I’ve rarely seen it done well, and all too often filmmakers or TV producers are content to assume that all surface gravity is equal. In this case I suppose it’s a forgivable break from reality given the film’s small budget, but it’s the one big disappointment in an otherwise very believable and well-researched portrayal of spaceflight. Still, it’s a minor glitch in a really excellent movie.

Gravity is a very different film, much more about visual spectacle and action. Indeed, I’d read that it definitely needed to be seen in 3D to get the full impact, so I decided to take a chance. See, nearly 30 years ago I had some laser surgery for a melanoma in my left eye, and that left my vision in that eye distorted, on top of my congenitally blurry vision in that eye. So normally my depth perception isn’t all that great, and I tend to be unable to perceive 3D images like those Magic Eye pictures that were a fad not long after my surgery. So I’ve always assumed that I wouldn’t be able to experience 3D movies. But a few years back, I talked to a friend who had similar eye problems, and he said he could occasionally get some sense of depth from a 3D movie. So for this case, I decided to give it a try. And lo and behold, it worked! I could actually perceive depth fairly normally, though mainly just when there was a considerable difference in range, like when something passed really close to the camera, or in the shots of Sandra Bullock receding into the infinite depths of space (which were the key shots where you pretty much need 3D to get the full impact). I’m not sure if someone with normal vision could perceive more than I did, but it worked pretty well, considering that I wasn’t sure if it would work at all. There were occasionally some shots where I got a double image when something bright was against black space, but the double image persisted when I closed one eye, so I think it was a matter of the glasses filtering out the second image imperfectly. Anyway, it’s nice to know I can see 3D movies (and I didn’t get a headache or nausea either), though it costs a few bucks extra, so I’ll probably use this newfound freedom judiciously — for movies where the 3D is really done well and serves a purpose, rather than just capitalizing on a fad or being sloppily tacked on.

Anyway, as for the movie itself, it’s a technical tour de force, one big ongoing special effect that uses remarkably realistic CGI to create the illusion of minutes-long unbroken shots of George Clooney and Sandra Bullock floating in space and interacting seamlessly with each other and their environs. The technical aspects of NASA procedures and equipment and so forth seem to be very realistically handled as well. And best of all, the movie states right up front in the opening text that in space there’s nothing to carry sound, and it sticks by that religiously, never giving into the temptation to use sound effects in vacuum no matter how cataclysmic things get and how many things crash or blow up. The only sounds we hear when the viewpoint astronauts are in vacuum are those that they could hear over their radios or through the fabric of their suits when they touch something. It’s utterly glorious. Every science-fiction sound designer in Hollywood needs to study this film religiously.

The behavior of objects and fluids in microgravity is moderately well-handled too, although I’m not convinced the fire in the ISS would spread as quickly as shown, since fires in space tend to snuff themselves out with no convection to carry away the carbon dioxide buildup. But there were glimpses of what seemed like ruptured gas canisters spewing blue flame, so maybe they were oxygen canisters feeding the fire? I also wasn’t convinced by the scene where Bullock’s character wept and the tears sort of rolled away from her eyes and drifted off. I think surface tension would cause the tears to cling around her eyes unless she brushed them away.

One thing that both films handle quite realistically is the coolness of trained professionals in a crisis. In both Europa Report and Gravity, for the most part the astronauts keep a calm and level tone of voice as they report their crises. In real life, professionals generally don’t get all shouty and dramatic when bad things happen, but they fall back on procedure and training and discipline and rely on those things to see them through. And that’s what we mostly get in both these movies, although Sandra Bullock’s character in Gravity has more panicky moments because she’s not as well-trained as the other astronauts. I’m not sure it’s entirely plausible that they would’ve let her go into space without sufficient training to accustom her to it, but it’s balanced by Clooney’s calm under pressure.

However… all that realism of detail in Gravity masks the fact that the basic premise of the movie requires fudging quite a bit about the physics, dimensions, and probabilities of orbital spaceflight. The crisis begins when an accidental satellite explosion starts a chain reaction that knocks out all the other satellites and creates a huge debris storm that tears apart the space shuttle and later endangers the ISS. Now, yes, true, orbital debris poses a serious risk of impact, but we’re still talking about small bits spread out over a vast volume. In all probability a shuttle or station would be hit by maybe one large piece of debris at most, not this huge oncoming swarm tearing the whole thing to pieces. And the probability of the same thing happening to two structures as a result of the same debris swarm? Much, much tinier. Not to mention that I really, really doubt the fragments as shown could impart enough kinetic energy to these spacecraft to knock them into the kind of spins we see. It’s all very exaggerated for the sake of spectacle. And by the climactic minutes of the film it’s starting to feel a bit repetitive and ridiculous that everything just keeps going so consistently wrong over and over. (The film also simplifies orbital mechanics a great deal, suggesting you can catch up with another orbiting craft just by pointing directly at it and thrusting forward. Since you and it are already moving very fast on curved paths, it’s really not that simple.)

Gravity has a huge edge over Europa Report in its budget and thus its ability to portray microgravity; I wish ER had been able to use this level of technology to simulate Europa’s 0.134g in its surface scenes. But as impressive as Gravity‘s commitment to realism is in some respects, it’s ultimately a far shallower film than ER and cheats the physics in much bigger ways for the sake of contrived action and danger. It’s essentially a big dumb disaster movie disguised with a brilliantly executed veneer of naturalism. Gravity has the style, while Europa Report has the substance.

Now what we need is for someone to put the two together, and we could really be onto something.

Enter the (collagen) matrix

Nearly a year ago, I posted about the minor periodontal surgery I had to deal with the receding gumline on my lower front teeth. I said there might be a second procedure to graft gum tissue from my palate into the receded area (to protect the roots of the front teeth), but I was hoping that wouldn’t be necessary. It soon enough became evident that it would be necessary, but I put it off as long as I could, until finally the peridontist’s office called me last month to schedule the procedure, which was done yesterday.

Turns out that putting it off worked out well, though, because in the interim, the doctor began doing a new version of the procedure which he offered me as an alternative. Instead of taking gum tissue from my upper palate, he could implant an artificial graft, basically just a scaffold of collagen (porcine in origin — I guess from pig hooves or something, but carefully purified and sterilized) that my own fibroblasts would grow into, forming new gum tissue to replace what was lost, with the collagen eventually breaking down and being “resorbed” into my body. So instead of taking existing gum tissue and moving it elsewhere, it’s enabling me to grow new gum tissue where the old tissue was lost.

The high-tech nature of the procedure appealed to me, as did the fact that it would simplify the operation and let me avoid the cutting into my upper palate. But I still took care to ask questions and read the documentation about the graft. There didn’t seem to be any significant drawbacks and there were definite advantages, so I agreed to the new procedure. It wasn’t very pleasant getting Novocaine stuck into my gums (though he used the sonic wand that temporarily numbed my nerves to ease the pain of the needle going in) and having him go in and pull things back and stitch things in, but it was easier than it would’ve been before the new grafts became available.

And now it’s the same drill as last time — ice packs and ibuprofen, soft foods and nothing hot for the first day or so, then no biting with the front teeth for about a month. Last time I found I was able to get by with a pretty normal diet so long as I cut things into small pieces, but I think I’ll still be having fewer sandwiches and more pasta salad for a while.

And within a couple of months or so, as long as I’m careful to avoid putting too much pressure on the area and crushing the collagen matrix so the cells can’t grow into it, I’ll have a nice new intact gumline there. I wish there were other parts of my body I could regenerate like that. Hopefully, by the time I need to, medical science will have made it possible.

Categories: Science, Uncategorized

Just to put things in perspective…

Yesterday was the start of the new year 2012… in the current version of the Gregorian calendar used in much of the world.  In the old Julian calendar, yesterday was December 19, 2011.  In the Hebrew calendar, we’re about three months from the end of the year 5772.  In the Indian civil calendar, we’re a similar distance from the end of 1933 Saka Era.  In the Islamic calendar, we’re early in the second month of 1433 AH.  To astronomers, yesterday was the Julian day 2455927.  In the traditional Chinese calendar, we’re a few weeks from the end of the year 28 (Year of the Metal Hare) of Cycle 78 (or Cycle 79 depending on whether you date from the beginning or the end of the reign of Emperor Huangdi).

The point is, calendrical divisions are arbitrary human constructs.  The Earth just moves continuously through its rotation and orbit from one moment to the next.  Some people make a huge deal out of the start of a new year in their particular calendar.  That’s fine, but it’s just an excuse for a party, not something that has any objective significance where the universe — or even the entirety of the human race — is concerned.  Worth keeping that in mind just for a sense of proportion.

Now, about this silly Mayan meme that’s going around… I wish we would stop blaming the Maya for this dumb apocalyptic prophecy.  The Maya (a more proper term than “Mayans”) had no apocalyptic tradition of any kind.  What they had was a calendar that worked very well, and that they used to date events in their own lives and up to a few generations in the future.  They probably never gave much thought to the year we call 2012, although they had a couple of written predictions/prophecies about events taking place long after that date.  A lot of the jokes and cartoons you see circulating posit that the “Mayans” actually manufactured calendars going up to this year and then stopped.  That’s not so.  They didn’t bother making calendars more than a few centuries ahead.  But the thing about calendars is, they’re cyclical.  They can easily be extrapolated forward indefinitely.  And the Maya calendar was really cyclical, since that was their view of time, that everything was a series of nested cycles that continued forward indefinitely.

So what happened was this: the actual Maya/Mesoamerican calendar fell into disuse many centuries ago.  More recently, in the mid-20th century, Western researchers reconstructed it and projected it forward into their own era, something the Maya themselves didn’t really bother to do, since why would they need to?  Those modern researchers discovered that one of the longer cycles of the Mesoamerican calendar, the 13th baktun cycle, would come to an end within their lifetimes, in the year 2012.  In 1966, a guy named Michael Coe wrote a book wherein he interpreted that as a Maya prophecy of what he called “Armageddon.”  But of course Armageddon is a Biblical concept, and later scholars have consistently debunked Coe’s interpretation.  There was nothing in Maya writings to suggest they saw the end of the 13th baktun as the end of the world — merely as the end of one cycle and the beginning of the next.  In other words, New Year’s Day writ large, an excuse for a huge party but nothing more.  Coe had imposed his own Western religious traditions onto his interpretation of a foreign culture — an elementary mistake for an archaeologist.  But that didn’t stop other 20th-century Westerners who believed in a looming Apocalypse from latching onto Coe’s mistake and building a whole eschatological cottage industry out of it.

So there is no “Mayan” prediction of the end of the world.  They don’t deserve the blame.  End-times theology is a distinctly Christian belief system and has been for thousands of years.  Many Christians since Biblical times have been convinced the world would end in their lifetimes, and they’ve always looked for “evidence” to justify the latest eschatological forecast.  The Maya calendar just had the bad luck of getting co-opted by that process and misinterpreted to fit it.  So please, let’s stop blaming the Maya for our own Western preoccupations.

Categories: Science Tags: ,
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