Tag Archives: universe

Stars Define Our Place in the Universe

6 Aug

http://www.npr.org/blogs/13.7/2013/08/03/208647989/how-to-fall-forever-into-the-night-sky?utm_source=npr&utm_medium=facebook&utm_campaign=20130805

How To Fall Forever Into The Night Sky

by Adam Frank

August 05, 201310:16 AM
The Milky Way dominates the sky over Chile's Atacama Desert, home to the European Southern Observatory.

The Milky Way dominates the sky over Chile’s Atacama Desert, home to the European Southern Observatory.

It’s your neck that’s the problem. Your neck is lying to you.

All your life you’ve had to look up at the stars. You walk along on a summer’s evening and they’re always there, those stars, those bright mysterious points of light, waiting for you to notice, waiting for you to understand what they are saying about time and space and your own place in it all.

But to see them you have to crane your neck. You have tilt back that big stone of a head to look up. Lets face it, that’s uncomfortable. And more to the point you can’t really sustain that head-craned-back position for anything more than a few minutes. That’s why the only way to really understand the real truth of the stars is to lie down.

First you’ll need to find a nice place, somewhere with the darkest skies possible. It’s got to be a good place to lie down too, someplace comfortable. A wide-open field is best. Then, once you have settled down in your dark, quiet spot take a long deep breath and face out.

That’s right, outwards, not up!

You see “up” is just an illusion. You’re living on the surface of massive rock that’s been pulling you down with its incessant gravity since the day you were born. It’s fooled you into thinking the stars are “up” there, “up” in the sky, high above you. They’re not.

Now that you are lying down, you can get to work. Imagine for a moment flattening the Earth into a thick wall. Imagine that this wall is not something below you but … behind you. You aren’t lying down anymore; you simply have your back pressed against something. And now what do you see in front of you?

Stars.

What do you see if you look toward your feet?

Stars.

And if you look to your right or your left or toward the direction the crown of your head is pointed, what’s there?

Stars.

Finally, we come to the real kicker. That wall your back is pressed up against, what’s behind it?

More stars!

There, now you have it. Now you can feel the real truth, like vertigo, as you fall into the starry multitude. These stars aren’t twinkling lights above your head, they are all suns; vast spheres of thermonuclear burning gas. And, as we have just recently come understand, almost all of those suns support their own families of planets. All those stars, all those other worlds — they’re everywhere. Now you can finally feel that you are there too, right in their midst.

Time now for the second big gestalt shift, the next change in perspective.

With your eyes aimed forward, focus on just one star. The sun (and its likely planets) that you are staring down lies more than 24 trillion miles away from you (a light year is about six trillion miles and the nearest star is more than four light years away). Now shift your focus and pick out another star, one that is close to the first. They look like neighbors. But that is just another deception. Your second star may be 10, 100 or 1,000 times farther away (or closer) than its neighbor.

All those stars, all of their planets, they aren’t pressed onto the surface of a dark upturned bowl; they’re arrayed in the three dimensions of cosmic space, like fireflies scattered across a summer field.

There is no up or down and you are not a resident of some city, some state or even some nation. You are not a Democrat or a Republican, a dockworker or a doctor. Right now, right at this very moment, you are a free agent hurtling through the midst of a vast city of stars, an all-encompassing architecture of suns.

So remember, always face outward into the surrounding sky. Because that is your true home.

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What’s in a number?

23 Apr

http://www.lastwordonnothing.com/2012/04/12/whats-in-a-number/

 

What’s In a Number

By Richard Panek | April 12, 2012 |

 

“Since there is an infinite number of alternative universes, there must be one in which there isn’t an infinite number of alternative universes. Perhaps this is it.”

 

No, that speculation didn’t come from the “Ask Mr. Cosmology” mailbag. It’s from a reader of New Scientist, courtesy of LWON’s own Sally, who is an editor at the magazine. She forwarded it to me because, she said, “it kind of made my head asplode.” After receiving reassurances from her that her head hadn’t actually spontaneously detonated—this is, after all, someone who is capable of falling into the Thames without any help—I sat and thought and tried to find the flaw in the logic.

 

The speculation has a logical basis in the current standard cosmological model. According to quantum theory, virtual particles should be popping into and out of existence all the time—and are, as experiments have repeatedly shown over the past six decades. In that case, the universe could be the product of one such quantum pop.

If it is, then it could have gone through a process that physicists call a “phase transition” and that everyone else calls “the thing that happens when water turns into ice or vice versa.” At the age of a trillionth of a trillionth of a trillionth of one second—that’s a 1 followed by 36 zeros, or 1036—the universe would have expanded ten septillion-fold—or to 1025 times its previous size. And it would have done so over the course of 1/1035 seconds.

And if inflation can pop one quantum universe into existence, then why not many? In fact, according to quantum theory, it should. It would, if inflation actually happened.

The inflationary universe. Also, Sally’s head.

 

The case for inflation isn’t airtight, but with every fresh observation of the Cosmic Microwave Background—the remnant echo of the Big Bang, loosely speaking—the evidence has looked better and better. Over the past decade, consensus has coalesced: We very likely did come from a quantum pop. In that case, our inflationary bubble would be one of an ensemble of 10500 universes. The number isn’t quite infinity, as the New Scientist reader suggests, but who’s counting?

Still, let’s say the number of universes is infinite. In that case, the reader’s argument goes like so:

A. The number of universes is infinite.

B. A universe exists in which the number of universes is not infinite.

C. This might be it.

When the argument is stated this starkly, the flaw in the logic becomes pretty clear. B contradicts A. “The number of universes is infinite” and “the number of universes is not infinite” can’t both be true. The contradiction, however, is obscured by the inclusion of “A universe exists in which.” The implication is that there’s something special about universes, something that, for instance, doorknobs don’t have. “Since there is an infinite number of doorknobs, there must be one for which there isn’t an infinite number of doorknobs” wouldn’t make anyone’s head asplode, except perhaps in bewilderment.

So what’s so special about universes that the existence of an infinite number of them would, for physics-savvy readers, somehow seem to suggest the necessary existence of one that allows the impossible?

I suspect the answer is quantum probability. According to quantum theory, everything is a matter of probability; therefore anything is possible. Anything. The probability that a butterfly will give birth to a dragon or that I will one day fall into the Thames is vanishingly small—but, technically, it’s not zero. Same with the emergence of a universe, or a cornucopia of universes, from nothing. The laws of physics allow it.

And that’s the implicit, but missing, “something special” in premise B: the laws of physics. As in “A universe exists in which the laws of physics require the number of universes to not be infinite.” What prompted the New Scientist reader, and what posed a threat to Sally’s noggin, was an unthinking assumption: that “the laws of physics”—in particular quantum theory—are part of the argument.

It’s a tempting assumption. According to current cosmological thinking, if an infinite ensemble of (or 10500, anyway) universes exists, then presumably each could come equipped with its own laws of physics. So couldn’t our universe be the one in which the laws of physics require that other universes don’t exist?

Yes—but only if our laws of physics have something to do with the other universes. We all, however, went our separate ways 13.7 billion years ago. Our laws of physics affect what happens within our universe, but there’s no reason to think they would influence the multiverse at large. Doorknobs, after all, don’t dictate the laws of physics.

Still, if they did, then maybe we could reframe the New Scientist‘s reader’s comment:

“Since there is an infinite number of alternative universes, there must be one in which there is just one alternative universe. Perhaps this is it.”

“Since there is an infinite number of alternative universes, there must be one in which there are two alternative universes. Perhaps this is it.”

“Since there is an infinite number of alternative universes, there must be one in which there are 2,125,179,218 alternative universes. Perhaps this is it.”

Memo to New Scientist staff: You can remove your plastic ponchos now.

Empty Space

16 Nov

This whole space thing… it’s big… and it’s full of nothing at all.

I can’t actually put the code in this post, so you have to go to the link for the actual pic/scale

http://www.phrenopolis.com/perspective/atom/index.html

And you thought there was a lot of empty space in the solar system. Well, there’s even more nothing inside an atom. A hydrogen atom is only about a ten millionth of a millimeter in diameter, but the proton in the middle is a hundred thousand times smaller, and the electron whizzing around the outside is a thousand times smaller than THAT. The rest of the atom is empty. I tried to picture it, and I couldn’t. So I put together this page – and I still can’t picture it.

The page is scaled so that the smallest thing on it, the electron, is one pixel. That makes the proton, this big ball right next to us, a thousand pixels across, and the distance between them is… yep, fifty million pixels (not a hundred million, because we’re only showing the radius of the atom. ie: from the middle to the edge). If your monitor displays 72 pixels to the inch, then that works out to eleven miles – making this possibly the biggest page you’ve ever seen (I personally have seen one that was set up to be even bigger, though its exact size did not seem to represent anything specific).

I recommend trying to scroll from here to the right a screen at a time, just to see how long it takes the little thumb in the scrollbar to move visibly. True masochists can try to scroll through the whole eleven miles – but the scenery along the way is pretty bleak.

I used to think that things like rocks and buildings and my own skeleton were fairly solid. But they’re made up of atoms, and atoms, as you can see here, contain so little actual material that they can barely be said to exist.

We are all phantoms.

(Note: users of older versions of Internet Explorer may not be able to scroll manually all the way to the right edge. If you want to actually see the electron, you may need to click HERE. Oddly, for some other users, this link will not work. Hopefully there is no one for whom both are true.)

If you don’t want to actually scroll through it…

Here’s the proton.

Now… the electron is ONE PIXEL… 11 miles away.

Bonus points if you can name what that “proton” is actually a picture of.

From Discover mag…

20 Things You Didn’t Know about Nothing

1. There is vastly more nothing than something. Roughly 74 percent of the universe is “nothing,” or what physicists call dark energy; 22 percent is dark matter, particles we cannot see. Only 4 percent is baryonic matter, the stuff we call something.

2. And even something is mostly nothing. Atoms overwhelmingly consist of empty space. Matter’s solidity is an illusion caused by the electric fields created by subatomic particles.

3. There is more and more nothing every second. In 1998 astronomers measuring the expansion of the universe determined that dark energy is pushing apart the universe at an ever-accelerating speed. The discovery of nothing—and its ability to influence the fate of the cosmos—is considered the most important astronomical finding of the past decade.

4. But even nothing has a weight. The energy in dark matter is equivalent to a tiny mass; there is about one pound of dark energy in a cube of empty space 250,000 miles on each side.

5. In space, no one can hear you scream: Sound, a mechanical wave, cannot travel through a vacuum. Without matter to vibrate through, there is only silence.

6. So what if Kramer falls in a forest? Luckily, electromagnetic waves, including light and radio waves, need no medium to travel through, letting TV stations broadcast endless reruns of Seinfeld, the show about nothing.

7. Light can travel through a vacuum, but there is nothing to refract it. Alas for extraterrestrial romantics, stars do not twinkle in outer space.

8. Black holes are not holes or voids; they are the exact opposite of nothing, being the densest concentration of mass known in the universe.

9. “Zero” was first seen in cuneiform tablets written around 300 B.C. by Babylonians who used it as a placeholder (to distinguish 36 from 306 or 360, for example). The concept of zero in its mathematical sense was developed in India in the fifth century.

10. Any number divided by zero is . . . nothing, not even zero. The equation is mathematically impossible.

11. It is said that Abdülhamid II, sultan of the Ottoman Empire in the early 1900s, had censors expunge references to H2O from chemistry books because he was sure it stood for “Hamid the Second is nothing.”

12. Medieval art was mostly flat and two-dimensional until the 15th century, when the Florentine architect Filippo Brunelleschi conceived of the vanishing point, the place where parallel lines converge into nothingness. This allowed for the development of perspective in art.

13. Aristotle once wrote, “Nature abhors a vacuum,” and so did he. His complete rejection of vacuums and voids and his subsequent influence on centuries of learning prevented the adoption of the concept of zero in the Western world until around the 13th century, when Italian bankers found it to be extraordinarily useful in financial transactions.

14. Vacuums do not suck things. They create spaces into which the surrounding atmosphere pushes matter.

15. Creatio ex nihilo, the belief that the world was created out of nothing, is one of the most common themes in ancient myths and religions.

16. Current theories suggest that the universe was created out of a state of vacuum energy, that is, nothing.

17. But to a physicist there is no such thing as nothing. Empty space is instead filled with pairs of particles and antiparticles, called virtual particles, that quickly form and then, in accordance with the law of energy conservation, annihilate each other in about 10-25 second.

18. So Aristotle was right all along.

19. These virtual particles popping in and out of existence create energy. In fact, according to quantum mechanics, the energy contained in all the power plants and nuclear weapons in the world doesn’t equal the theoretical energy contained in the empty spaces between these words.

20. In other words, nothing could be the key to the theory of everything.

More food for thought re: scale of the universe

Award winning astrophotographer Thierry Legault wanted to image the Hubble Space Telescope and space shuttle Atlantis traveling together around Earth.
But how? The pair wouldn’t fly over his hometown in France during the ongoing servicing mission. To catch the rare meeting of spaceships, he decided to do some traveling of his own–all the way to Florida. Yesterday, from a location 100 kilometers south of the Kennedy Space Center, he pointed his telescope at the sun and there they were:

“I took this picture of Atlantis and HST transiting the sun on May 13th at 12:17 p.m. EDT. It was just before the shuttle reached out with its robotic arm to grapple Hubble,” says Legault. “The two spaceships were at an altitude of 600 km and they zipped across the sun in only 0.8 seconds.” He captured the split-second transit using a solar-filtered Takahashi 5-inch refracting telescope and a Canon 5D Mark II digital camera.


You

17 May

Just some scientific food for thought on a lazy morning while packing to leave town for a few days [with no intentions of starting a religious or philosophical debate]. It just struck me as a very thought provoking piece that is somehow introspective on a cosmological scale… as bipolar as that sounds.

This is the first part of the introduction to Bill Bryson’s A Short History of Nearly Everything.

Welcome. And congratulations. I am delighted that you could make it. Getting here wasn’t easy, I know. In fact, I suspect it was a little tougher than you realize.

To begin with, for you to be here now trillions of drifting atoms had somehow to assemble in an intricate and intriguingly obliging manner to create you. It’s an arrangement so specialized and particular that it has never been tried before and will only exist this once. For the next many years (we hope) these tiny particles will uncomplainingly engage in all the billions of deft, cooperative efforts necessary to keep you intact and let you experience the supremely agreeable but generally under-appreciated state known as existence.

Why atoms take this trouble is a bit of a puzzle. Being you is not a gratifying experience at the atomic level. For all their devoted attention, your atoms don’t actually are about you – indeed, don’t even know that you are there. They don’t even know that they are there. They are mindless particles, after all, and not even themselves alive. (It is a slightly arresting notion that if you were to pick yourself apart with tweezers, one atom at a time, you would produce a mound of fine atomic dust, none of which had ever been alive but all of which had once been you.) Yet somehow for the period of your existence they will answer to a single overarching impulse: to keep you you.

The bad news is that atoms are fickle and their time of devotion is fleeting – fleeting indeed. Even a long human life adds up to only about 650,000 hours. And when that modest milestone flashes past, or at some other point thereabouts, for reasons unknown your atoms will shut you down, silently disassemble, and go off to be other things. And that’s it for you.

Still, you may rejoice that it happens at all. Generally speaking in the universe it doesn’t, so far as we can tell. This is decidedly odd because the atoms that so liberally and congenially flock together to form living things on Earth are exactly the same atoms that decline to do it elsewhere. Whatever else it may be, at the level of chemistry life it curiously mundane: carbon, hydrogen, oxygen and nitrogen, a little calcium, a dash of sulfur, a light dusting of other very ordinary elements – nothing you wouldn’t find in any ordinary drugstore – and that’s all you need. The only thing special about the atoms that make you is that they make you. That is of course the miracle of life.

Whether or not atoms make life in other corners of the universe, they make plenty else; indeed they make everything else. Without them there would be no water or air or rocks, no stars and plants, no distant gassy clouds or swirling nebulae or any of the other things that make the universe so usefully material. Atoms are so numerous and necessary that we easily overlook that they needn’t actually exist at all. There is no law that requires the universe to fill itself with small particles of matter or to produce light and gravity and the other physical properties on which our existence hinges. There needn’t actually be a universe at all. For the longest time there wasn’t. There were no atoms and no universe for them to float about in. There was nothing – nothing at all anywhere.

So thank goodness for atoms. But the fact that you have atoms and they assemble in suck a willing manner is only part of what got you here. To be here now, alive in the twenty-first century and smart enough to know it, you also had to be the beneficiary of an extraordinary string of biological good fortune. Survival on Earth is a surprisingly tricky business. Of the billions and billions of species of living things that have existed wince the dawn of time, most – 99.9 percent – are no longer around. Life on Earth, you see, is not only brief but dismayingly tenuous. It is a curious feature of our existence that we come from a plane that is very good at producing life but even better at extinguishing it.

The average species on Earth lasts for only about four million years, so if you wish to be around for billions of years, you must be as fickle as the atoms that made you. You must be prepared to change everything about yourself – shape, size, color, species affiliation, everything – and to do so repeatedly. That’s much easier said than done, because the process of change is random. To get form “protoplasmal primordial atomic globule” (as Gilbert and Sullivan put it) to sentient upright modern human has required you to mutate new traits over and over in a precisely timely manner for an exceedingly long while. So at various periods over the last 3.8 billion years you have abhorred oxygen, then doted on it, grown fins and limbs and jaunty sails, laid eggs, flicked the air with a forked tongue, been sleek, been furry, lived underground, lived in trees, been as big as a deer, and as small as a mouse, and a million things more. The tiniest deviation from any of these evolutionary shifts, and you might now be licking algae from cave walls or lolling walruslike on some stony shore or disgorging air through a blowhole in the top of your head before diving sixty feet for a mouthful of sandworms.

Not only have you been lucky enough to be attached since time immemorial to a favored evolutionary line, but you have also been extremely – make that miraculously – fortunate in your personal ancestry. Consider the fact that for 3.8 billion years, a period of time older than the Earth’s mountains and rivers and oceans, everyone of your forebears on both sides has been attractive enough to find a mate, healthy enough to reproduce, and sufficiently blessed by fate and circumstances to live long enough to do so. Not one of your pertinent ancestors was squashed, devoured, drowned, starved, stranded, stuck fast, untimely wounded, or otherwise deflected from its life’s quest of delivering a tiny charge of genetic material to the right partner at the right moment in order to perpetuate the only possible sequence of hereditary combinations that could result – eventually, astoundingly, and all too briefly – in you.

”The more I examine the universe and study the details of its architecture, the more evidence I find that the universe in some sense must have known we were coming.”

– Freeman Dyson

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