If there's any possible way to corrupt spacetime, resulting in a sphere of destruction that expands outward at the speed of light, then maybe an accelerating universe could act as a firewall. What if we're here because the non-accelerating universes with intelligent life tend to get wiped out?
I can see the elegance of using fractal math to explain the big bang, cosmological expansion and the apparent structure our universe exhibits (as opposed to being an inert soup).
I first read about this many years ago, in Olav Stapledon's brilliant Star Maker, about a man who takes a magical mystery tour through the whole of time and space:
"Then the Star Maker said, "Let there be light." And there was light. From all
the coincident and punctual centers of power, light leapt and blazed. The
cosmos exploded, actualizing its potentiality of space and time. The centers
of power, like fragments of a bursting bomb, were hurled apart. But each one
retained in itself, as a memory and a longing, the single spirit of the whole;
and each mirrored in itself aspects of all others throughout all the cosmical
space and time.
"No longer punctual, the cosmos was now a volume of inconceivably dense matter
and inconceivably violent radiation, constantly expanding. And it was a
sleeping and infi-nitely dissociated spirit.But to say that the cosmos was
expanding is equally to say that its members were contracting. The ultimate
centers of power, each at first coincident with the punctual cosmos,
themselves generated the cosmical space by their disengagement from each other.
The expansion of the whole cosmos was but the shrinkage of all its physical
units and of the wave-lengths of its light. Though the cosmos was ever of
finite bulk, in relation to its minutiae of light-waves, it was boundless and
center-less. As the surface of a swelling sphere lacks boundary and center, so
the swelling volume of the cosmos was boundless and center-less. But as the
spherical surface is centered on a point foreign to it, in a "third dimension,"
so the volume of the cosmos was centered in a point foreign to it, in a
"fourth dimension."
"The congested and exploding cloud of fire swelled till it was of a planet's
size, a star's size, the size of a whole galaxy, and of ten million galaxies.
And in swelling it became more tenuous, less brilliant, less turbulent.
Presently the cosmical cloud was disrupted by the stress of its expansion in
conflict with the mutual clinging of its parts, disrupted into many million
cloudlets, the swarm of the great nebulae.
"For a while these were as close to one another in relation to their bulk as
the flocculations of a mottled sky. But the channels between them widened,
till they were separated as flowers on a bush, as bees in a flying swarm, as
birds migrating, as ships on the sea. More and more rapidly they retreated
from one another; and at the same time each cloud contracted, becoming first
a ball of down and then a spinning lens and then a featured whirl of star-
streams.
"Still the cosmos expanded, till the galaxies that were most remote from one
another were flying apart so swiftly that the creeping light of the cosmos
could no longer bridge the gulf between them."
Yes, I remember that as well, great book by the way.
As much as I'd like to attribute clairvoyance to Olaf Stapledon also with regard to his fictional(?) mystical out of body experience, I'm skeptic. There already was a big bang theory and the red- and blueshift of starlight was already discovered. So I'd think speculation that some galaxies are speeding away from us faster then the speed of light was not impossible in 1936, am I right?
Georges Lemaître had proposed an early version of the Big Bang theory in 1931. In 1936 it was nowhere near the scientific consensus -- that didn't happen until the discovery of the Cosmic Microwave Background, 29 years later.
But knowledge of the Big Bang and the Hubble redshift aren't, by themselves, sufficient to explain what Stapledon wrote. Those things just show that the universe has expanded. For most of the 20th century, people assumed that the acceleration of the universe would diminish -- either asymptotically approaching zero, or reversing into a "Big Crunch". For the galaxies to accelerate beyond the point where photons can bridge the gaps between them, they need to not only have been accelerated, but to keep accelerating, which is a very unintuitive notion (what would be driving the acceleration?)
My guess is that Stapledon was influenced by Einstein's Cosmological Constant, which predicted exactly this kind of acceleration, but which Einstein himself had repudiated several years earlier, calling it "his biggest blunder". When I first read Star Maker in 1997, I figured that even if Stapledon had been up-to-the-minute about the Big Bang, he somehow hadn't gotten the memo about the Cosmological Constant. So I chalked this passage up as one of several things that Stapledon had definitely gotten wrong.
A year later, Dark Energy was discovered, and suddenly it appeared that Stapledon was right all along. This did my head in a bit. Somehow, Stapledon had been spectacularly smart/lucky in crafting his story from a mix of freshly-proposed and freshly-discarded theories. So no, clairvoyance isn't strictly necessary to explain this. But just to be safe, I'll retain that parenthetical question mark after "fictional(?)" when describing Star Maker.
I think you're correct about the motivation for the cosmological constant. By adjusting the sign of the sign of the constant, you could produce a universe which was expanding, contracting, or steady-state. When Hubble's constant got nailed down, that definitively meant that the universe was expanding, and Einstein was happy to accept that. The problem was that if you tweak the constant to produce that result, then it also says that the universe is not only expanding, but accelerating. Which didn't seem to make the slightest bit of sense, so Einstein dropped it, and Stapledon didn't.
(Standard disclaimer: I'm not a cosmologist, and probably have no idea what I'm talking about.)
Fascinating! I think it's better to look at Hubble's law then the cosmological constant in this particular regard. Hubble's law was published at the end 20's decade. If you contemplate the law it follows naturally (although counter-intuitively) that very far away galaxy's might speed away from each other faster then the speed of light. How this can be understood with regard to relativistic effects or the uncross-able universal light speeding law is another intriguing topic.
So perhaps Stapledon thought of this or someone else thought about this (Lemaitre?) and Stapledon read or heard it.
With regard to the cosmological constant, Einstein dropped it but Lemaitre didn't. Lemaitre argued in the early 1930's that the rate of expansion of the universe was accelerating.
http://www.amazon.com/The-Day-Without-Yesterday-Cosmology/dp...
"Lemaître was then invited to London in order to take part in a meeting of the British Association on the relation between the physical Universe and spirituality. There he proposed that the Universe expanded from an initial point, which he called the "Primeval Atom" and developed in a report published in Nature.[15] Lemaître himself also described his theory as "the Cosmic Egg exploding at the moment of the creation"; it became better known as the "Big Bang theory," a pejorative term coined during a BBC radio broadcast by Fred Hoyle who was an obstinate proponent of the steady state universe, even until his death in 2001."
http://en.wikipedia.org/wiki/Georges_Lema%C3%AEtre
So some have (mistakenly) attributed intuition of dark energy to Einstein and his cosmological constant or some like you would argue that Stapledon was spectacularly smart or lucky but I think I'd attribute it to Lemaitre and I think indirectly (or directly) Stapledon heard or read about this. Perhaps as an academic he was even present at the "British Association" meetup on science and spirituality.
But if so, why did Lemaitre keep Einstein's cosmological constant in his own work and why did he think the expansion rate of the universe was increasing?
Even so I'd like to believe Stapledon really was traveling among the stars 'in some way', also his description of the out of body experience is oddly similar to credible accounts later in the 20th century and might be autobiographical but if not could be explained by him reading earlier accounts of this psychological effect.
This kind of comment is what keeps me coming back to Hacker News. I didn't know that Lemaître had proposed that the expansion was accelerating -- actually, I didn't know much about Lemaître at all, truth be told. ( The Day Without Yesterday just went on my reading list -- thanks!). In any case, I guess Stapledon must have been working off of Lemaître's model, rather than cooking up something unique.
Still, like you, I do like to imagine that Stapledon tapped into something that was somehow beyond the ordinary. I don't feel like speculating beyond that, but however he did it, Star Maker is an extraordinary book.
As a humble scientist Lemaître didn't take the credit of the discovery of the expanding universe. Appearently there was a nice presentation by experimental particle astrophysicist Ariel Goobar at "Symposium - Georges Lemaître’s Big Bang In Modern Cosmology: A Celebration" last month:
https://fys.kuleuven.be/ster/meetings/lemaitre/programme
At the end it states:
"SNIa cosmology provides stunning confirmation of cosmic expansion – as predicted by Lemaitre in 1927!
• Expansion currently accelerating – as proposed early on by Lemaitre to explain the age of the Universe
• Is it Einstein’s CC or some exotic new phenomena? Observers busy trying to find out. Theory badly needed!"
Stapledon's works have inspired me to no end. He is brilliant and visionary. I humbly believe if his works were written now, they would still be ahead of their time. Now, as to the following:
1. fsiekfen: "Even so I'd like to believe Stapledon really was traveling among the stars 'in some way', also his description of the out of body experience is oddly similar to credible accounts later in the 20th century and might be autobiographical but if not could be explained by him reading earlier accounts of this psychological effect."
2. nkoren: "Still, like you, I do like to imagine that Stapledon tapped into something that was somehow beyond the ordinary. I don't feel like speculating beyond that, but however he did it, Star Maker is an extraordinary book."
The two of you and others I assume, might be curious to know about "The Opening of The Eyes" (there used to be an online version here (http://olafstapledonarchive.webs.com/openingoftheeyes_index....) but it's down now. If you like, I could make the .mobi file I created available somewhere from the various parts.
Not commonly known, as far as I can tell, even among Stapledon fans. It was published posthumously by his wife and is written in the first person. Essentially, it's an essay by him to his "creator". I won't comment on what that entails; hopefully his work speaks for itself. But within that story he mentions this - the exact quote:
"Long ago (it was while I was scrambling on a rugged coast, where great waves broke in blossom on the rocks) I had a sudden fantasy of man's whole future, aeon upon aeon of strange vicissitudes and gallant endeavours in world after world, seeking a glory never clearly conceived, often betrayed, but little by little revealed."
It says... something. I'm not sure what. Either way, the piece is a powerful expose on the author. You get to see a lot into his mindset, and even into the challenges he faced in relation to his proposed philosophies. Some interesting commentary on Christianity as well, among others.
But in the end, I guess you get the feeling there's more to him than simple imaginative power. The concept of "fiction as cover for non-fiction (so people will read your stuff without calling you a lunatic) tends to crop up in some of his works too. Either way, his works are nothing short of incredible.
hi cosmicadvocate, thanks so much for your comment! I've been wondering years about his worldview as I recognized much of it from my own questions and answers. If only he'd be alive!
The link is fortunately still present in the internet archive, but if you have a mobi version handy that would be nice for offline reading on my ipad kindle app. You can sent it to fsieFKen at gmail.
There is more to him then simple creativity, he was an academic philosopher and romantic, yearning for the spiritual and his mystic side really shows in this book.
There is some similarity with other writers like the dutch Frederik van Eeden (psychiatrist) and his book "The Deeps of Deliverance", Herman Hesse, Kahlil Gibran and Dostojevski.
"Olaf Stapledon married Agnes Zena Miller, a first cousin from Australia, on July 16, 1919, at Friends Meeting House, a Quaker establishment at Reigate, Surrey. Agnes, the oldest of four children, was born in New Zealand on May 25, 1894, the daughter of Frank Edward and Margaret Barnard Miller. Frank was a brother of Olaf's mother, Margaret the daughter of Charles Barnard, headmaster of a Quaker school in Yorkshire..." Stapledon spent four years in the Friends Quaker Ambulance Corps. "Although he was involved with socialist groups and contributed some articles to leftist journals, Stapledon's earliest literary aspirations were poetic. His first book was Latter-Day Psalms, published in 1914 by Henry Young and Sons, Ltd., of Liverpool." Stapledon's writing reflected intense wrestling with concepts of God and faith.
Also: Olaf's agnosticism also derived from his parents. His father apparently subscribed to no sect at all, so any direct religious influence would therefore have had to come from his mother. She was a Unitarian... In his mature years Stapledon denied that he was a Christian, although the increasing strain of mysticism in his work from the 1940's on indicated a deep-rooted sense of religiosity. [Source: Olaf Stapledon: The Man Behind the Works, by Sam Moskowitz.]
http://www.adherents.com/people/ps/Olaf_Stapledon.html
There is more to him then simple creativity, he was an academic philosopher and romantic, yearning for the spiritual and his mystic side really shows in this book.
I know! I rushed a bit there, but one of things I cherish about Stapledon is his devotion to the nuance of the intangible, the senses, the "spirit" to which he so often refers. Perhaps one of his crowning contributions is that he melds embracing reality as it is and the essence of worship; it's so rare to find the two in the same place, I've found. Maybe I haven't search enough, and will take a trip through some of your suggestions, so thank you. And that link - an interesting site! Thank you for that as well.
For me, for what it's worth, I had spent years searching for something I couldn't quite place, and once I found him, realized it was this tremendous sense of scope, our littleness and such sensitivity to thought and creativity. At time he's so rich in descriptiveness a break helps, sure, and then you pick up again where you left off.
if I interpret this correctly (British) copyright expired in 2000 as Stapledon died in 1950.
"In the 1911 Act the term of author's copyright was extended to the lifetime of the author and 50 years thereafter; this remained the case under the 1956 Act and the 1988 Act.
The 1911 Act in effect extended the meaning of "author" so that this period of copyright applied to all types of works, not merely printed works.
Under the 1995 Regulations (set out below), the period of author's copyright was further extended, to the lifetime of the author and 70 years thereafter."
http://en.wikipedia.org/wiki/Copyright_law_of_the_United_Kin...
It is very interesting that essentially there are causally disconnected subsets of the universe - each a sub universe onto their own. Although globally not possible, is the gravitational collapse scenario plausible for some of these causally disconnected subsets? Tying it with the fact that galaxies seem to be slowly eaten by their black hole centers, would this be an example of a local gravitational collapse?
And when this process is over, what happens to all the black holes, isolated from everything else.. do they just dissipate out, creating a uniform, cold, low entropy universe?
It would be a uniform, cold, high entropy universe. The highest entropy possible. Once all the black holes had eaten through all matter and subsequently all radiated away (via Hawking radiation).
If we could achieve near-light speed, how would time work for those traveling at that speed relative to the universe ? Wouldn't time "feel" normal but "stopped" relative to the other slower bodies of the universe ? As such, couldn't that near-light speed "slow down" the rate at wich we see the expansion of the universe, making possible star traveling ?
Being aboard a spaceship that's accelerated to such speeds would feel pretty normal internally, but the outside universe would pass by very quickly and processes in that universe would appear to be impossibly fast. Accelerated to a very significant fraction of c would allow you to visit practically everywhere in the galaxy within a few years of ship time. But on the outside, millennia will have passed.
You can see why that's not practical, because everything you left behind would be gone. Still, there are scenarios where this might be a valid solution.
However, you could never reach a destination that's speeding away from you faster than the speed of light. Because you can't accelerate your spacecraft beyond that speed, parts of the universe will always be unreachable - which is the point of the article.
You might wonder why galaxies moving away from each other faster than the speed of light works at all given the cosmic speed limit. The answer is that their "movement" is not normal, inertial movement as we know it. Instead you might imagine that new space is being created in between them, driving them away from each other by simply scaling up the distances involved.
Given the practical and theoretical limits on spacecraft acceleration, people have been thinking about a different way to travel, a way that doesn't involve momentum but instead manipulates spacetime to simply shift an object to another position without acceleration. The article hints at this as well. It makes sense because technically the acceleration and deceleration part of a journey is wasteful and limiting. At this time, it's the only way we know how to get from A to B, but we're all hopeful that one or more alternatives can be researched which allow us to simply go somewhere else without using traditional movement.
I wonder if this has any impact on the Fermi Paradox? Could it be that any sufficiently advanced civilization finds itself beyond the "red out" horizon before having a chance to say hello to anyone else? (Pure speculation of course, but so is the question in the first place.)
Almost certainly not. You don't need to leave our galaxy to make the case for Fermi's paradox. Something more like a Great Filter (http://en.wikipedia.org/wiki/Great_Filter) is more likely in play.
I seem to remember from physics class that mass cannot travel faster than the speed of light, so how is it possible for galaxies to be unreachable if you managed to travel at the speed of light?
It is possible because the galaxies are not travelling faster than light. Space is expanding.
Consider if you were travelling on the surface of an expanding balloon. Your distance from the starting point would increase faster than your speed relative to the surface at your current spot, because the part of the surface you'd already travelled across would continue expanding. Now do that in three dimensions.
If you're going to bake an Apple pie from scratch, first you must invent the universe. But before that, buy a high dimensional superluminally expanding hyper oven.
Just use a spherical oven and perform a geometric inversion with origin the centre of the oven and radius the oven's radius. Then all the pie inside will become outside and the outside will fold inside and you'll have infinite space for pie. As easy as capturing a lion.
Imagine that you go running with a friend. You run at 0.9 * speed of light and your friend runs at 0.8 * speed of light in the exact opposite direction. How fast are you getting away from each other?
I'm not sure I understand. It seems like you're implying that the two people would be moving away from each other faster than the speed of light, but I was under the impression that that's not the case. I thought that each person would observe the other travelling at C?
1.7c for an observer just standing around and watching the two guys run. I am not sure what it looks like from the point of view of the runners without calculating it but they should see a speed smaller than the speed of light.
I'm looking at the bright side, it means that we don't even need to achieve speed of light to travel to other galaxies, because the universe is ever-expanding it means that some planets will occupy the space our planet is in now, so theoretically if we can figure how to live in a static point in the universe (e.g, absolute position, not relative to our solar system) some day in the future (millions of years from now) we could visit other galaxies.
There is no such point (or it is everywhere if you like, as someone else had said).
The best analogy I've seen is that of ants on a balloon. They live in what appears to them to be a two dimensional universe. As you inflate the balloon, they observe their own universe getting bigger. But the "point where the Big Bang happened" to them is not a point that even exists in their universe any more. They cannot get back there, since the higher third dimension does not exist in their universe.
This illustrates the confusion that occurs when people are exposed to horrible "artistic renderings" of the Big Bang as a huge explosion that throws matter all over the place.
It's better to think of the Big Bang as an unimaginably intense period of expansion and cooling of whatever substance the earliest universe was made out of (see Inflation theory). It was not an explosion that happened in a pre-existing spacetime.
I'm pretty convinced we will either die out or fill the galaxy with people. If we can start the reaction by going one other place and inhabiting it I think it will ultimately set off a chain reaction. Lots of work to do between now and then but it seems like its mostly engineering now vs new discoveries.
> Lots of work to do between now and then but it seems like its mostly engineering now vs new discoveries.
I'm not sure what you mean by this. There are still lots of issues with just surviving the journey, let alone making a foreign planet habitable and establishing a society. We need lots more discoveries in energy and understanding human physiology before it becomes just an engineering problem.
Beyond the reachability limit, there's something even sadder, but possibly even more poetic: the comoving future visibility limit. That's the surface beyond which, although matter may exist, light from it will never reach us. In terms of time, it's very, very early - before the luminous phase of the big bang which gives us the cosmic microwave background.
It's the very last thing on the map of the universe:
There is actually a whole sequence of such limits: the visibility limit (where light emitted in the distant past reaches us now) is furthest out, then comes the reachability limit (where light emitted by us now can still be observed), then the round trip limit where we can send a message now and recieve an answer (before we are beyond their reachability limit), then the limit where we can send a message, recieve an answer and then send a final goodbye, then the limit for two full exchanges, and so on...
