ARCH – novella (excerpt)

A.R.C.H. – Applied Research and Controlled Habitat

He couldn’t figure out how it could’ve happened, and how it could’ve happened to the ARCH’s armory and a select few cryo-pods. The ship’s Security Officer, Greg Scott, figured it was sabotage. There was no one on board except those on the ship’s manifest and EVE1 would’ve told them if there had been any stowaways though that idea in itself was ludicrous. They were in cryo-suspension for the last twenty years and only a skeleton crew had been removed from the cryo-pods to manually land the ARCH. They’d only just started waking the others.

Brenin Klihp was the Chief Engineer in charge of the Hyperspace Tunnel and with Arty North, the Systems Analyst for EVE1, occupying one of those cryo-pods destroyed, Brenin found himself in charge of far more than he’d agreed to. The landing was dicey but EVE1 helped a lot. When they woke SO Scott, Brenin wished they hadn’t. He could still hear Scott’s acerbic voice ringing behind his temples.

“Am I expected to have sexual intercourse with all the men on this ship?”

A flat, expressionless voice inquired from behind him. The content of the words and the fact that his fourteen year old daughter was saying them made him whip his whole body around to face her.

“What?”

“I’ve menstruated and am capable of becoming pregnant. Am I supposed to repopulate this planet if the humans from Earth . . . “ his daughter paused, tapped her fingers three times on the nearest flat surface and clacked her teeth down in one decisive jolt. Brenin always worried that she would damage her teeth doing that. He thought she’d stopped doing that but it was a tense time, and her nervous ticks would present themselves whenever she was, “. . . for some reason can’t make it here?”

“Oh Jesus.” In all the frantic rushing around he’d forgotten how anxious this whole situation must be for Kitty.

Kit Klihp just stared at her father, waiting for the rest of his response.

“Where’d you get an idea like that, Kitty?”

“I’m 14,” she said, somberly. “I know about human sexual reproduction.”

“Well, no! God, no! Kitty. Don’t. And you don’t have to! And if anyone tries to,” he paused in disbelief that he was about to utter the words to his fourteen-year-old daughter, “engage in sexual relations with any of the men on this ship. And if they do try anything, please tell me. You’re 14!”

“But biologically, I’m capable of-“

“But Jesus! You’re 14!”

“I never thought you were so religious, Father,” she stared at him. In the silence she sniffled, and then immediately touched her nose three times; another one of her ticks. “Because you keep mentioning God and Jesus.”

“No, I . . . I just . . . Kitty, this is making me really uncomfortable.”

“Why?”

“Just, just got back to reading, sweetie. And no sex talk until you’re . . . 25,” he started to swivel back in his chair but his daughter’s voice stopped him.

“Why 11 years?” She furrowed her brow and looked off to a space beyond her father, through the flight deck and into the wilderness of Gliese 581g. “That seems arbitrary. Is there something about human anatomy that I missed in my research that presents itself at 25?”

“Go read, honey,” Brenin said softly. “Or go see Victoria and ask her.”

“Does she know something more about sexual intercourse that you don’t, Father?”

“Well . . . she’s a woman,” Brenin said, hoping that’d be the end.

“Good point,” she said flatly and turned on her heels to exit the room.

“See you at supper,” he called after her.

She stopped at the door, “I’m glad I don’t have to be sexually intimate with any of the men. I find the whole idea disagreeable.”

“Remember, it’s always your choice,” he looked at her to make sure she was focused on his voice. “Kitty, don’t ever do something you don’t want to do. Always do what you think is right!”

She nodded silently and stepped into the hallway. The automatic door hissed closed behind her.

First Habitable Exoplanet? Climate Simulation Reveals New Candidate That Could Support Earth-Like Life

Via Science Daily

Schematic of the global climate model used to study Gliese 581d. Red / blue shading indicate hot / cold surface temperatures, while the arrows show wind velocities at 2 km height in the atmosphere. (Credit: © LMD/CNRS)

Are there other planets inhabited like Earth, or at least habitable? The discovery of the first habitable planet has become a quest for many astrophysicists who look for rocky planets in the “habitable zone” around stars, the range of distances in which planets are neither too cold nor too hot for life to flourish.

In this quest, the red dwarf star Gliese 581 has already received a huge amount of attention. In 2007, scientists reported the detection of two planets orbiting not far from the inner and outer edge of its habitable zone. While the more distant planet, Gliese 581d, was initially judged to be too cold for life, the closer-in planet was thought to be potentially habitable by its discoverers. However, later analysis by atmospheric experts showed that if it had liquid oceans like Earth, they would rapidly evaporate in a ‘runaway greenhouse’ effect similar to that which gave Venus the hot, inhospitable climate it has today. A new possibility emerged late in 2010, when a team of observers led by Steven Vogt at the University of California, Santa Cruz, announced that they had discovered a new planet, which they dubbed Gliese 581g, or ‘Zarmina’s World’. This planet, they claimed, had a mass similar to that of Earth and was close to the centre of the habitable zone. For several months, the discovery of the first potential Earth twin outside the Solar System seemed to have been achieved. Unfortunately, later analysis by independent teams has raised serious doubts on this extremely difficult detection. Many now believe that Gliese 581g may not exist at all. Instead, it may simply be a result of noise in the ultra-fine measurements of stellar ‘wobble’ needed to detect exoplanets in this system.

Today, it is finally Gliese 581g’s big brother — the larger and more distant Gliese 581d — which has been shown to be the confirmed potentially habitable exoplanet by Robin Wordsworth, François Forget and co-workers from Laboratoire de Météorologie Dynamique (CNRS, UPMC, ENS Paris, Ecole Polytechnique) at the Institute Pierre Simon Laplace in Paris. Although it is likely to be a rocky planet, it has a mass at least seven times that of Earth, and is estimated to be about twice its size. At first glance, Gliese 581d is a pretty poor candidate in the hunt for life: it receives less than a third of the stellar energy Earth does and may be tidally locked, with a permanent day and night side. After its discovery, it was generally believed that any atmosphere thick enough to keep the planet warm would become cold enough on the night side to freeze out entirely, ruining any prospects for a habitable climate.

To test whether this intuition was correct, Wordsworth and colleagues developed a new kind of computer model capable of accurately simulating possible exoplanet climates. The model simulates a planet’s atmosphere and surface in three dimensions, rather like those used to study climate change on Earth. However, it is based on more fundamental physical principles, allowing the simulation of a much wider range of conditions than would otherwise be possible, including any atmospheric cocktail of gases, clouds and aerosols.

To their surprise, they found that with a dense carbon dioxide atmosphere — a likely scenario on such a large planet — the climate of Gliese 581d is not only stable against collapse, but warm enough to have oceans, clouds and rainfall. One of the key factors in their results was Rayleigh scattering, the phenomenon that makes the sky blue on Earth. In the Solar System, Rayleigh scattering limits the amount of sunlight a thick atmosphere can absorb, because a large portion of the scattered blue light is immediately reflected back to space. However, as the starlight from Gliese 581 is red, it is almost unaffected. This means that it can penetrate much deeper into the atmosphere, where it heats the planet effectively due to the greenhouse effect of the CO2 atmosphere, combined with that of the carbon dioxide ice clouds predicted to form at high altitudes. Furthermore, the 3D circulation simulations showed that the daylight heating was efficiently redistributed across the planet by the atmosphere, preventing atmospheric collapse on the night side or at the poles.

Scientists are particularly excited by the fact that at 20 light years from Earth, Gliese 581d is one of our closest galactic neighbours. For now, this is of limited use for budding interstellar colonists — the furthest-travelled human-made spacecraft, Voyager 1, would still take over 300,000 years to arrive there. However, it does mean that in the future telescopes will be able to detect the planet’s atmosphere directly. While Gliese 581d may be habitable there are other possibilities; it could have kept some atmospheric hydrogen, like Uranus and Neptune, or the fierce wind from its star during its infancy could even have torn its atmosphere away entirely. To distinguish between these different scenarios, Wordsworth and co-workers came up with several simple tests that observers will be able to perform in future with a sufficiently powerful telescope.

If Gliese 581d does turn out to be habitable, it would still be a pretty strange place to visit — the denser air and thick clouds would keep the surface in a perpetual murky red twilight, and its large mass means that surface gravity would be around double that on Earth. But the diversity of planetary climates in the galaxy is likely to be far wider than the few examples we are used to from the Solar System. In the long run, the most important implication of these results may be the idea that life-supporting planets do not in fact need to be particularly like Earth at all

Astronomers Find First Evidence Of Other Universes

Our cosmos was “bruised” in collisions with other universes. Now astronomers have found the first evidence of these impacts in the cosmic microwave background

Multi Verse

© Technology Review

There’s something exciting afoot in world of cosmology. Last month, Roger Penrose at the University of Oxford and Vahe Gurzadyan at Yerevan State University in Armenia announced that they had found patterns of concentric circles in the cosmic microwave background, the echo of the Big Bang.

This, they say, is exactly what you’d expect if the universe were eternally cyclical. By that, they mean that each cycle ends with a big bang that starts the next cycle. In this model, the universe is a kind of cosmic Russian Doll, with all previous universes contained within the current one.

That’s an extraordinary discovery: evidence of something that occurred before the (conventional) Big Bang.

Today, another group says they’ve found something else in the echo of the Big Bang. These guys start with a different model of the universe called eternal inflation. In this way of thinking, the universe we see is merely a bubble in a much larger cosmos. This cosmos is filled with other bubbles, all of which are other universes where the laws of physics may be dramatically different to ours.

These bubbles probably had a violent past, jostling together and leaving “cosmic bruises” where they touched. If so, these bruises ought to be visible today in the cosmic microwave background.

Now Stephen Feeney at University College London and a few pals say they’ve found tentative evidence of this bruising in the form of circular patterns in cosmic microwave background. In fact, they’ve found four bruises, implying that our universe must have smashed into other bubbles at least four times in the past.

Again, this is an extraordinary result: the first evidence of universes beyond our own.

So, what to make of these discoveries. First, these effects could easily be a trick of the eye. As Feeney and co acknowledge: “it is rather easy to find all sorts of statistically unlikely properties in a large dataset like the CMB.” That’s for sure!

There are precautions statisticians can take to guard against this, which both Feeney and Penrose bring to bear in various ways.

But these are unlikely to settle the argument. In the last few weeks, several groups have confirmed Pernose’s finding while others have found no evidence for it. Expect a similar pattern for Feeney’s result.

The only way to settle this will be to confirm or refute the findings with better data. As luck would have it, new data is forthcoming thanks to the Planck spacecraft that is currently peering into the cosmic microwave background with more resolution and greater sensitivity than ever.

Cosmologists should have a decent data set to play with in a couple of years or so. When they get it, these circles should either spring into clear view or disappear into noise (rather like the mysterious Mars face that appeared in pictures of the red planet taken by Viking 1 and then disappeared in the higher resolution shots from the Mars Global Surveyor).

Planck should settle the matter; or, with any luck, introduce an even better mystery. In the meantime, there’s going to be some fascinating discussion about this data and what it implies about the nature of the Universe. We’ll be watching.

Reference

First Observational Tests of Eternal Inflation

Concentric Circles In WMAP Data May Provide Evidence Of Violent Pre-Big-Bang Activity

What would the Universe look like if there were 2 dimensions of time?

*taken from http://www.io9.com

Question (posed by Richard Henretta on io9.com’s Facebook page): This could easily be classified a stoner question, but what would the universe look like if there were 2 dimensions of time?

Answer (from Dr. Dave Goldberg from io9.com): It is a stoner question, but that won’t stop me from answering it. Let me dispense with the obvious. From a macroscopic perspective, there are three dimensions in space. I don’t care if you call them up-down,left-right,and forward-back, or x,y,z, or whatever you like. The fact is that we can only move in three-d.

There is also just a single dimension of time, and the main difference between time and space is that unlike with space, you only get to move through time one way, and at a rate of 1 second/second. It’s this succession of events through time that define our experiences. Within the timeline of a single individual, it always makes sense to say, “A came before B.” Once you start with multiple observers and relativity, all bets are off, but let’s not get distracted with that today. It doesn’t change the fact that in any local frame, there’s just one way for time to go.

But why is the universe made this way? Everything we know about the standard model is built on the assumption that the universe has 3+1 dimensions, but it doesn’t actually tell uswhy that has to be the case.

As hardcore geeks, many of you are probably familiar with M-theory, which says (among much else) that in reality, the universe has ten spatial dimensions and one for time. All but three of those spatial dimensions are presumably very small; they would essentially be a Pacman universe on scales not only much smaller than you and me, but also on scales smaller than atomic nuclei.

Suppose, for a moment, that M theory is right. Is there a place in the multiverse with more than 3 macro dimensions? Sure, there might be. But we couldn’t live there, and as I’ll try to argue below, neither could anything else.

I’m going to make a bunch of anthropic arguments, and somebody is going to get their panties in a twist by saying that we don’t know that life has to be like it is here on earth. True enough, but I’m making some reasonable assumptions. That is, I’m assuming complex molecules and atoms heavier than hydrogen need to be able to form. Since we’ve never seen extra-terrestrial (let alone extra-universal) life, I could be wrong. That’s a chance I’m willing to take.

So what’s the (weak) anthropic argument? The basic idea is that there isn’t just a single set of physical parameters that describe the universe, but that you’ll only find intelligent (or any) creatures trying to be physicists in regions of the universe that are conducive to life. We talk a fair amount about this in the “User’s Guide to the Universe”, where we address, for example, why physical constants might actually vary in different patches of the multiverse.

So what’s wrong with anything but 3+1?

Why are past, present, and future our only options?
Image via Flatland the movie.

Why not live in Flatland?

We’ll start easy. I’m sure many of you have read Edwin Abott’s beloved Flatland. If you haven’t, the premise is that a (literal, geometric) square tells us all about the physics and civilization of his two-dimensional world. I assure you that it’s more interesting than it sounds.

The problem with such a world is one of complexity. To pick a particularly gross example. Imagine yourself as a two-dimensional amoeba. A mouth-type opening takes in some food. How does your digestive system work? Well, presumably, there’s a tube running through you, ending at your tuchus. The problem is that in 2-d, such a tube would split you in half. In other words, for your digestive system to work, your mouth would also have to serve double-duty as your butt.

Grossness aside, there’s a general problem in two dimensions, let alone in one. Systems and organisms simply can’t be complex enough to form anything approaching intelligence. For instance, because you can’t cross things in 2-d, neurons wouldn’t be able to cross one another, and brains (or anything like it) would be very, very limited.

Why are past, present, and future our only options?
Sculpture by Rob Millar

How about a Tesseractland with 4 dimensions?
It’s easy to think about 2 dimensional universes, because we can draw them on paper or computer screens. It’s far harder to visualize what life would be like in a universe with morethan three dimensions. We have to at least consider the possibility, however. If M theory is right and there really are 10 dimensions, why are so many of them compact, and only three of them big? You’ve probably already seen Rob Bryanton’s “Imagining the tenth dimension”, but if you haven’t, you should check it out.

Just because we can imagine a 10 dimensional universe doesn’t mean that we (or anything like us) could ever live in one. I’m going to drop a little old-school classical mechanics on you. You may remember, dimly, something about gravity being an inverse square law. The idea is that if you double the distance between two objects, their force of gravity drops by a factor of four. The same rule holds for electromagnetism.

The inverse square law isn’t an accident. It turns out that it’s entirely a function of the fact that we live in a three-dimensional universe. If we lived a four-dimensional one then we’d have an inverse cube law.

It turns out, though, that an inverse square law is very special. Higher dimensional universes (with their inverse cube or inverse-fourth gravity laws or whatever) don’t have any stable orbits. In other words, in a 4-dimensional universe, the earth would either spiral in toward the sun or fly away. We wouldn’t get to enjoy the five billion or so years of nearly constant sunlight that we do in our universe.

This is true for all orbiting bodies (including planets, comets, stars in the galaxy and so on), but the situation gets even worse — at least from an anthropic point of view. Because electromagnetism also obeys an inverse square law, it turns out that atoms wouldn’t be stable. They’d all spontaneously collapse. It’s really hard to imagine complex life without atoms, and even tougher to imagine having this conversation without the existence of life.

A note to the experts. Somebody is likely to point out in the comments section that electrons don’t “orbit” atoms in the same way that planets do the sun. True enough, but if you grind through the equations in quantum mechanics and do the problem correctly, you hit the same problem. No stable atoms. Sorry.

What’s so weird about 2 dimensions of time?

So we’re limited to three dimensions in space, but what about perhaps having more than one dimension of time?

To put it bluntly, the universe would be confusing. Even talking about it is confusing. MIT Physicist Max Tegmark has a very nice discussion of what life would be like in a universe with two dimensions of time, and I’m quite shamelessly borrowing from his work here. (Warning: the original paper is a bit on the mathematical side).

Every person (and particle, for that matter) would move through two different times, t1 and t2. But these two times can’t proceed at exactly the same rate, because if they did, it would be exactly the same as if the universe had only one dimension of time. More generally, if you’re alone in this freaky universe, you probably wouldn’t even notice that anything is wrong.

But things get awkward if you have a friend. (Use your imagination if necessary.)

Normally, if you meet up with someone, it’s because you’re at (more or less) the same coordinates in space during an overlapping period of time. The problem is that if the two people are moving through the different time coordinates at different rates then even though they might remain in the same place, they won’t remain in the same time.

Put more simply, while your personal clock may run normally, unless your loved ones are all on the same world-lines you’re destined never to see them again.

But even supposing you’re an angry loner, living in a two-spatial-dimensional universe is going to be tough. The big thing (and the one must likely to spawn debate in the discussion section) has to do with the fact that with 2 time dimensions (and at least two space dimensions), you can’t say anything useful about the “future.” One of the things that makes an intelligent observer is that I (assuming I am one) can look around and based on the state of things around me, determine with some probability what will happen elsewhere at some point in the future. With two dimensions of time, you simply can’t do that. I’ll skip the math, but the basic idea is that the “future” isn’t very well defined if you’ve got two time dimensions. If there’s no inference, there’s no prediction and no science. It’s very hard to imagine how creatures in those sorts of circumstances could make any decisions at all.

Life is unpredictable enough with one dimension of time; two would just be ridiculous.

Dave Goldberg is the author, with Jeff Blomquist, of “A User’s Guide to the Universe: Surviving the Perils of Black Holes, Time Paradoxes, and Quantum Uncertainty.” (follow us on twitterfacebook or our blog.) He is an Associate Professor of Physics at Drexel University. Feel free to send email to askaphysicist@io9.com with any questions about the universe.

Send an email to Dave Goldberg, the author of this post, at askaphysicist@io9.com.