Showing posts with label multiverse. Show all posts
Showing posts with label multiverse. Show all posts

Wednesday, June 11, 2014

How Would Humans Know If They Lived in a Multiverse?


What? You mean we may not live in a multiverse?

Be that as it may, this is a brief but interesting article from Live Science.

How Would Humans Know If They Lived in a Multiverse?

By Tanya Lewis, Staff Writer | June 02, 2014


Our universe may be one of many, physicists say.
Credit: Shutterstock/Victor Habbick

Some theories in physics give rise to the idea of multiple universes, where nearly identical versions of the known universe exist. But if such a multiverse does exist, how would people know, and what would it mean for humanity?

There may be ways to find out if the known universe is one of many, said Brian Greene, a theoretical physicist and author at Columbia University in New York.

"There are certain versions of the multiverse that, should they be correct, might be most susceptible to confirmation," Greene told Live Science. [5 Reasons We May Live in a Multiverse]

Spotting a multiverse

For example, in the multiverse suggested by string theory, a model that says the universe is composed of one-dimensional strings, the known universe might exist on a giant 3D membrane, Greene told Live Science.

In such a world, "if the universe is a loaf of bread, everything we know about takes place on one slice," he said. Conceivably, debris from collisions that migrated off our slice into the wider cosmos might leave missing energy signatures, which a particle accelerator like the Large Hadron Collider at CERN might be able to detect, Greene said.

Some theories of inflation, the notion that the universe expanded rapidly in the first fractions of a second after the Big Bang, suggest another kind of multiverse. The Big Bang could be one of many big bangs, each giving rise to its own universe — a cosmic bubble in a sea of other bubbles.

In such a scenario, the known universe might collide with another one, which might leave an imprint on the cosmic microwave background, the radiation signature left over from the Big Bang, Greene said.

Greene stressed that all of these notions are highly speculative — "There's reason to take the ideas seriously, but they are far from science fact," he said.

Is free will dead?

But if a multiverse does exist, it could have some wacky consequences. A world with an infinite number of universes would virtually ensure that conditions in one universe would repeat in another, Greene said. In other words, there would almost certainly be another version of you reading this article, written by another version of me.

In such a multiverse, you might decide to read the article in one universe and not read it in another. What would that mean for the notion of free will?

Perhaps it's a moot point. "I think free will bit the dust long before multiverse theory," Greene said.

Scientific equations describe the particles that make up all matter, including humans, Greene said. While more-complex structures arise that have no relevance to a single particle — temperature, for instance — everything still has a "fundamental microphysical underpinning," he said.

That means free will is merely a human sensation, not actual control.

"When I move my teapot, that sensation is absolutely real," Green said. "But that's all it is. It's a sensation."

Maybe in another universe, there's a Brian Greene that believes in free will.

Follow Tanya Lewis on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on Live Science.

Sunday, March 30, 2014

The Biocentric Multiverse - An Example of [Eroneously] Collapsing the Subjective and the Objective


A few years ago (2009), Dr. Robert Lanza published Biocentrism: How Life and Consciousness are the Keys to Understanding the True Nature of the Universe, a model he claims positions consciousness as foundation of the universe as we know it. In essence, he argues that our consciousness of the universe brings it into being, which is based on a faulty understanding of quantum mechanics.

Lanza, like Deepak Chopra and B Alan Wallace, relies on a misunderstanding of the Heisenberg Uncertainty Principle to suggest that observation is necessary to the determination of the state of a quantum system. But there is research that disproves this interpretation.

First, here is an excellent explanation of Heisenberg's model (Geoff Brumfiel, Nature News, Sept 11, 2012):
At the foundation of quantum mechanics is the Heisenberg uncertainty principle. Simply put, the principle states that there is a fundamental limit to what one can know about a quantum system. For example, the more precisely one knows a particle's position, the less one can know about its momentum, and vice versa. The limit is expressed as a simple equation that is straightforward to prove mathematically.

Heisenberg sometimes explained the uncertainty principle as a problem of making measurements. His most well-known thought experiment involved photographing an electron. To take the picture, a scientist might bounce a light particle off the electron's surface. That would reveal its position, but it would also impart energy to the electron, causing it to move. Learning about the electron's position would create uncertainty in its velocity; and the act of measurement would produce the uncertainty needed to satisfy the principle.
He then reports some research [Rozema, L. A. et al. 2012. Phys. Rev. Lett. 109(100404)] that supports the belief that measurement does not always introduce more uncertainty in a system:
The researchers made a ‘weak’ measurement of the photon’s polarization in one plane — not enough to disturb it, but enough to produce a rough sense of its orientation. Next, they measured the polarization in the second plane. Then they made an exact, or 'strong', measurement of the first polarization to see whether it had been disturbed by the second measurement.

When the researchers did the experiment multiple times, they found that measurement of one polarization did not always disturb the other state as much as the uncertainty principle predicted. In the strongest case, the induced fuzziness was as little as half of what would be predicted by the uncertainty principle.
This research doesn't do away with the uncertainty principle, but it does demonstrate that it is possible to measure some features of a quantum system without introducing noise into the system.

A related idea is the Shroedinger's Cat thought experiment, which is often taken as proof of the Copenhagen interpretation of quantum mechanics. This model proposes that the act of observing a system results in the collapse of all possible states into one state, the observed state. This is known as the wavefunction collapse. Heisenberg's uncertainty principle is one of the six basic tenets of the Copenhagen interpretation, a term that is actually a misnomer in that there was never any coherent interpretation associated with this model. The notion that there was a Copenhagen interpretation arose when Heisenberg used it in his refutation of David Bohm's model, a move he later regretted.

[Bohm's model, the implicate, explicate, and generative orders (via Wikipedia), proposes that
"things, such as particles, objects, and indeed subjects" exist as "semi-autonomous quasi-local features" of an underlying activity. These features can be considered to be independent only up to a certain level of approximation in which certain criteria are fulfilled.
Bohm, working with the then Stanford-based neuroscientist, Karl Pribram, extended this into a holonomic model of the brain.]

One of the more difficult aspects of the Copenhagen model, the Heisenberg Uncertainty Principle, was also known as the EPR paradox, developed by  Albert Einstein and his colleagues Boris Podolsky and Nathan Rosen. One of the issues Einstein noted with the then-standard model of quantum mechanics is that it allowed for a version of quantum entanglement that violates the general theory of relativity - i.e., that nothing moves faster than the speed of light. But Heisenberg's Uncertainty Principle allowed for exactly that, so the EPR paradox was developed. Via Wikipedia:
Heisenberg's principle was an attempt to provide a classical explanation of a quantum effect sometimes called non-locality. According to EPR there were two possible explanations. Either there was some interaction between the particles, even though they were separated, or the information about the outcome of all possible measurements was already present in both particles.
The EPR authors (EPR combines the first letter of the three men's last names) preferred the latter of these two explanations, which allowed that the general relativity remained intact. The EPR solution to the problem was local hidden variables, but Bell's Theorem has since been accepted as a successful refutation of the hidden variables.

A more recent model, the Relational quantum mechanics (RQM) model, developed by Carlo Rovelli in 1994, offers a way out of one of the more difficult aspects of the Copenhagen model, the EPR paradox. The RQM treats the state of a quantum system as being observer-dependent, that is, the state is the relation between the observer and the system.

Again, from Wikipedia:
The physical content of the theory is not to do with objects themselves, but the relations between them. As Rovelli puts it: "Quantum mechanics is a theory about the physical description of physical systems relative to other systems, and this is a complete description of the world".[2]

The essential idea behind RQM is that different observers may give different accounts of the same series of events: for example, to one observer at a given point in time, a system may be in a single, "collapsed" eigenstate, while to another observer at the same time, it may appear to be in a superposition of two or more states. Consequently, if quantum mechanics is to be a complete theory, RQM argues that the notion of "state" describes not the observed system itself, but the relationship, or correlation, between the system and its observer(s). The state vector of conventional quantum mechanics becomes a description of the correlation of some degrees of freedom in the observer, with respect to the observed system. However, it is held by RQM that this applies to all physical objects, whether or not they are conscious or macroscopic (all systems are quantum systems). Any "measurement event" is seen simply as an ordinary physical interaction, an establishment of the sort of correlation discussed above. The proponents of the relational interpretation argue that the approach clears up a number of traditional interpretational difficulties with quantum mechanics, while being simultaneously conceptually elegant and ontologically parsimonious.
The RQM model offers the best solution to the EPR Paradox, and it does so without relying on super-luminal information transfer (faster than the speed of light):
Thus the relational interpretation, by shedding the notion of an "absolute state" of the system, allows for an analysis of the EPR paradox which neither violates traditional locality constraints, nor implies superluminal information transfer, since we can assume that all observers are moving at comfortable sub-light velocities. And, most importantly, the results of every observer are in full accordance with those expected by conventional quantum mechanics.
Returning specifically the Biocentrism model of Lanza, (a condensed matter physicist) and Ajita Kamal (an evolutionary biologist) offered a great "debunking" of Lanza's model, noting that it is the philosophical stance known as idealism masquerading as science. The title of their article (2009) is "Biocentrism Demystified: A Response to Deepak Chopra and Robert Lanza’s Notion of a Conscious Universe," posted at Nirmukta.

Here is one small section in which they correct Lanza's misrepresentation of objective reality:
Lanza says “Space and time are simply the mind’s tools for putting everything together.” This is true , but there is a difference between being the ‘mind’s tools’ and being created by the mind itself. In the first instance the conscious perception of space and time is an experiential trick that the mind uses to make sense of the objective universe, and in the other space and time are actual physical manifestations of the mind. The former is tested and true while the latter is an idealistic notion that is not supported by science. The experiential conception of space and time is different from objective space and time that comprise the universe. This difference is similar to how color is different from photon frequency. The former is subjective while the latter is objective.

Can Lanza deny all the evidence that, whereas we humans emerged on the scene very recently, our Earth and the solar system and the universe at large have been there all along? What about all the objective evidence that life forms have emerged and evolved to greater and greater complexity, resulting in the emergence of humans at a certain stage in the evolutionary history of the Earth? What about all the fossil evidence for how biological and other forms of complexity have been evolving? How can humans arrogate to themselves the power to create objective reality?
Here is more from their long and erudite article, this section dealing with the many worlds model, another approach based on a dissatisfaction with the Copenhagen model:
Hugh Everett, during the mid-1950s, expressed total dissatisfaction with the Copenhagen interpretation: ‘The Copenhagen Interpretation is hopelessly incomplete because of its a priori reliance on classical physics … as well as a philosophic monstrosity with a “reality” concept for the macroscopic world and denial of the same for the microcosm.’ The Copenhagen interpretation implied that equations of quantum mechanics apply only to the microscopic world, and cease to be relevant in the macroscopic or ‘real’ world.

Everett offered a new interpretation, which presaged the modern ideas of quantum decoherence. Everett’s ‘many worlds’ interpretation of quantum mechanics is now taken more seriously, although not entirely in its original form. He simply let the mathematics of the quantum theory show the way for understanding logically the interface between the microscopic world and the macroscopic world. He made the observer an integral part of the system being observed, and introduced a universal wave function that applies comprehensively to the totality of the system being observed and the observer. This means that even macroscopic objects exist as quantum superpositions of all allowed quantum states. There is thus no need for the discontinuity of a wave-function collapse when a measurement is made on the microscopic quantum system in a macroscopic world.

Many worlds
Wave function bifurcation

Everett examined the question: What would things be like if no contributing quantum states to a superposition of states are banished artificially after seeing the results of an observation? He proved that the wave function of the observer would then bifurcate at each interaction of the observer with the system being observed. Suppose an electron can have two possible quantum states A and B, and its wave function is a linear superposition of these two. The evolution of the composite or universal wave function describing the electron and the observer would then contain two branches corresponding to each of the states A and B. Each branch has a copy of the observer, one which sees state A as a result of the measurement, and the other which sees state B. In accordance with the all-important principle of linear superposition in quantum mechanics, the branches do not influence each other, and each embarks on a different future (or a different ‘universe’), independent of the other. The copy of the observer in each universe is oblivious to the existence of other copies of itself and other universes, although the ‘full reality’ is that each possibility has actually happened. This reasoning can be made more abstract and general by removing the distinction between the observer and the observed, and stating that, at each interaction among the components of the composite system, the total or universal wave function would bifurcate as described above, giving rise to multiple universes or many worlds.

A modern and somewhat different version of this interpretation of quantum mechanics introduces the term quantum decoherence to rationalise how the branches become independent, and how each turns out to represent our classical or macroscopic reality. Quantum computing is now a reality, and it is based on such understanding of quantum mechanics.
And, finally, if one is to deal with Lanza's model, then one must deal with the definition of consciousness, a definition that is largely not agreed upon by an two theorists, it seems. Here is the refutation of Lanza's model on the grounds that he hopelessly muddles the definition of consciousness:
One criticism of biocentrism comes from the philosopher Daniel Dennett, who says “It looks like an opposite of a theory, because he doesn’t explain how consciousness happens at all. He’s stopping where the fun begins.”

The logic behind this criticism is obvious. Without a descriptive explanation for consciousness and how it ‘creates’ the universe, biocentrism is not useful. In essence, Lanza calls for the abandonment of modern theoretical physics and its replacement with a magical solution. Here are a few questions that one might ask of the idea:
  1. What is this consciousness?
  2. Why does this consciousness exist?
  3. What is the nature of the interaction between this consciousness and the universe?
  4. Is the problem of infinite regression applicable to consciousness itself?
  5. Even if Lanza’s interpretation of the anthropic principle is a valid argument against modern theoretical physics, does the biocentric model of consciousness create a bigger ontological problem than the one it attempts to solve?
And this:
Consider this statement by Lanza:
“Consciousness cannot exist without a living, biological creature to embody its perceptive powers of creation.“
How can consciousness create the universe if it doesn’t exist? How can the “living, biological creature” exist if the universe has not been created yet? It becomes apparent that Lanza is muddling the meaning of the word ‘consciousness.’ In one sense he equates it to subjective experience that is tied to a physical brain. In another, he assigns to consciousness a spatio-temporal logic that exists outside of physical manifestation. In this case, the above questions become: 1. What is this spatio-temporal logic?; 2. Why does this spatio-temporal logic exist? and so on…

The Cartesian Theater
The Cartesian Theater

Daniel Dennett’s criticism of biocentrism centres on Lanza’s non-explanation of the nature of consciousness. In fact, even from a biological perspective Lanza’s conception of consciousness is unclear. For example, he consistently equates consciousness with subjective experience while stressing its independence from the objective universe (see Lanza’s quote below). This is an appeal to the widespread but erroneous intuition towards Cartesian Dualism. In this view, consciousness (subjective experience) belongs to a different plane of reality than the one on which the material universe is constructed. Lanza requires this general definition of consciousness to construct his theory of biocentrism. He uses it in the same way that Descartes used it – as a semantic tool to deconstruct reality. In fact, Lanza’s theory of biocentrism is a sophisticated non-explanation for the ‘brain in a vat’ problem that plagued philosophers for centuries. However, instead of subscribing to Cartesian Dualism, he attempts a Cartesian Monism by invoking quantum mechanics. To be exact, his view is Monistic Idealism - the idea that consciousness is everything- but the Cartesian bias is an essential element in his arguments.
Lanza's model relies on a form of dualism that is disguised as idealistic monism.

Furthermore, his denial of any scientific understanding of consciousness is a straw man argument and it is empty, considering that Lanza proposes no useful mechanism for consciousness, nor a definition, but still gives it a central role in his theory of the universe.

For me, the Relational quantum mechanics model offers the best solution to many of the problems of quantum theory, including the role of consciousness. It is an essentially postmodern model of physics, while much of earlier quantum theory is still bogged down in an mechanistic model.

All of that is simply my way of saying that the article below, a defense of the Biocentric model from Jonathan Lyons at Institute for Ethics and Emerging Technologies is sadly misguided.

A Biocentric Multiverse



Jønathan Lyons

Ethical Technology

Posted: Mar 24, 2014

I’ve been thinking of ways in which Biocentric Universe Theory and multiverse theory could both be true. What if our nature as conscious beings inhabiting a multiverse of endless possibilities, where we are quantum-superposition beings, actually all adds up to us creating the multiverse, while perceiving time and space only within the limitations of our immediately observable, three-spatial/one-time-dimensional universe?

Down the rabbit hole!



Big Guns in the physics community are embracing multiverse theory more and more. One interpretation of this theory is that everything that can possibly happen, does happen, in one universe or another.

Background: Robert Lanza’s Biocentric Universe Theory

Robert Paul Lanza is an American medical doctor, scientist, Chief Scientific Officer of Advanced Cell Technology and Adjunct Professor at the Institute for Regenerative Medicine, Wake Forest University School of Medicine. (For more on Dr. Lanza, and for some fascinating essays and articles containing further insight into Biocentric Universe Theory, visit his Website: http://www.robertlanza.com/


  • At subatomic level, everything exists in an undefined state until observed
  • Example: Double-slit experiment
  • The Observer Effect
  • Because of this evidence, holds Biocentric Universe Theory, it is consciousness that creates the universe as we know it, and not the other way around.
Each but the last of those statements is experimentally proven; the last is a tantalizing possibility, and one I wish to continue to learn about.

A multiverse — that is, an infinite number of universes — could be stacked one on top of the other in even a tiny, single, spatial dimension in addition to the three spatial dimensions and single time dimension we experience. And in an eleven-dimensional multiverse, there are plenty of dimensions left to go around after we account for the four we can perceive.

al outcomes. Next, consider the observer effect: That the universe does not become solid until it is observed is demonstrated by the dual-slit experiment and the observer effect. What this means is that at the subatomic level, the entire universe exists as a colossal Schroedinger Probability wave, existing only as potentialites.

Until, that is, it is observed.

At that point the wave function collapses from whatever probabilities were possible to the single, actual outcome. Before it is observed. the universe exists in a superposition:
“Quantum superposition is a fundamental principle of quantum mechanics that holds that a physical system—such as an electron—exists partly in all its particular theoretically possible states (or, configuration of its properties) simultaneously; but when measured or observed, it gives a result corresponding to only one of the possible configurations (as described in interpretation of quantum mechanics).”
In Biocentric Universe Theory, as I mentioned, consciousness thereby gives rise to the universe, and not the other way around. It does so through the act of observation. In observing the universe, we cause the collapse of the Probability Wave to its single outcome. In our universe, anyway.

What if the act of observation is the tool by which new universes are created?

Comic Interlude: An actual product you can buy over at ThinkGeek: “$20 kit produces trillions of universes."

Are you willing to take on the responsibility that comes with bringing trillions of universes into existence, each teeming with sentient life? That's something to ponder before plunking down $20 for this make-your-own-universe kit, created by <artist Jonathon Keats.

If two events are possible, quantum theory assumes that both occur simultaneously - until an observer determines the outcome. For example, in Schrödinger's famous thought experiment, in which his cat may have been killed with a 50 per cent probability, the cat is both alive and dead until someone checks. When the observation is made, the universe splits into two, one for each possible outcome. For example, Schrödinger's cat would be alive in one universe and dead in the other universe.”

Quantum physicists say that this is exactly what happens. The ongoing, infinite production of the multiverse would, therefore, be an ongoing act of creation caused by observation continuously collapsing probability wave, continuously forcing subatomic particle from a quantum superposition representing all possibilities open to them, not to a single outcome, but to a single outcome in a single universe; it would also cause every other possibility represented by the probability wave to occur in every universe where the same event is being observed.

Enter time:
​If all time is simultaneous, than our nature as conscious beings could also be described as our nature as quantum-superposition beings; consider the Scrodinger’s Cat thought experiment:
“One can even set up quite ridiculous cases. A cat is penned up in a steel chamber, along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance, so small, that perhaps in the course of the hour one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges and through a relay releases a hammer that shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed. The psi-function of the entire system would express this by having in it the living and dead cat (pardon the expression) mixed or smeared out in equal parts.

It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a "blurred model" for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.

—Erwin Schrödinger, Die gegenwärtige Situation in der Quantenmechanik (The present situation in quantum mechanics), Naturwissenschaften (translated by John D. Trimmer in Proceedings of the American Philosophical Society)”
While I would argue that the cat’s consciousness would probably play some role in the timing of the wave’s collapse, the main point is this: by this reasoning, when we enter a period in which the cat may or may not be dead, then its living or dead status has not been observed, and the cat herself exists in a superposition — that is, if you will, neither zero (dead) nor one (alive), but both, simultaneously.

If all time is simultaneous, then we humans are simultaneously one (alive) during our lifespans and zero (dead) outside our lifespans. Meaning that we, and all forms of life, are beings who exist in superposition, spread out across time and the multiverse, expressing every potentiality that could ever be — indeed, creating every such potentiality.

Because if our nature is that of conscious beings inhabiting a multiverse of endless possibilities, where we are quantum-superposition beings, all of this actually adds up to us creating the multiverse by observing parts of it, while perceiving time and space only within the limitations of our immediately observable, three-spatial/one-time-dimensional universe.



Jønathan Lyons is an affiliate scholar for the IEET. He is also a transhumanist parent, an essayist, and an author of experimental fiction both long and short. He lives in central Pennsylvania and teaches at Bucknell University. His fiction publications include Minnows: A Shattered Novel.


Thursday, March 20, 2014

Big Bang Discovery Opens Doors to the "Multiverse" (National Geographic)

This short article (considering the subject matter) from National Geographic Daily News is a good explainer about Monday's announcement of gravitational waves and how that discovery opens the door even wider for multiverse theories (that our universe is only one of MANY universes separated by vast distances of space).

Big Bang Discovery Opens Doors to the "Multiverse"

Gravitational waves detected in the aftermath of the Big Bang suggest one universe just might not be enough.


This illustration depicts a main membrane out of which individual universes arise; they then expand in size through time. 
Written by Dan Vergano
National Geographic
Published March 18, 2014

Bored with your old dimensions—up and down, right and left, and back and forth? So tiresome. Take heart, folks. The latest news from Big Bang cosmologists offers us some relief from our humdrum four-dimensional universe.

Gravitational waves rippling through the aftermath of the cosmic fireball, physicists suggest, point to us inhabiting a multiverse, a universe filled with many universes. (See: "Big Bang's 'Smoking Gun' Confirms Early Universe's Exponential Growth.")

That's because those gravitational wave results point to a particularly prolific and potent kind of "inflation" of the early universe, an exponential expansion of the dimensions of space to many times the size of our own cosmos in the first fraction of a second of the Big Bang, some 13.82 billion years ago.

"In most models, if you have inflation, then you have a multiverse," said Stanford physicist Andrei Linde. Linde, one of cosmological inflation's inventors, spoke on Monday at the Harvard-Smithsonian Center for Astrophysics event where the BICEP2 astrophysics team unveiled the gravitational wave results.

Essentially, in the models favored by the BICEP2 team's observations, the process that inflates a universe looks just too potent to happen only once; rather, once a Big Bang starts, the process would happen repeatedly and in multiple ways. (Learn more about how universes form in "Cosmic Dawn" on the National Geographic website.)

"A multiverse offers one good possible explanation for a lot of the unique observations we have made about our universe," says MIT physicist Alan Guth, who first wrote about inflation theory in 1980. "Life being here, for example."

Lunchtime

The Big Bang and inflation make the universe look like the ultimate free lunch, Guth has suggested, where we have received something for nothing.

But Linde takes this even further, suggesting the universe is a smorgasbord stuffed with every possible free lunch imaginable.

That means every kind of cosmos is out there in the aftermath of the Big Bang, from our familiar universe chock full of stars and planets to extravaganzas that encompass many more dimensions, but are devoid of such mundane things as atoms or photons of light.

In this multiverse spawned by "chaotic" inflation, the Big Bang is just a starting point, giving rise to multiple universes (including ours) separated by unimaginable gulfs of distance. How far does the multiverse stretch? Perhaps to infinity, suggests MIT physicist Max Tegmark, writing for Scientific American.

That means that spread across space at distances far larger than the roughly 92 billion light-year width of the universe that we can observe, other universes reside, some with many more dimensions and different physical properties and trajectories. (While the light from the most distant stuff we can see started out around 14 billion light-years away, the universe is expanding at an accelerating rate, stretching the boundaries of the observable universe since then.)

Comic Mismatches

"I'm a fan of the multiverse, but I wouldn't claim it is true," says Guth. Nevertheless, he adds, a multiverse explains a lot of things that now confuse cosmologists about our universe.

For example, there is the 1998 discovery that galaxies in our universe seem to be spreading apart at an accelerating rate, when their mutual gravitational attraction should be slowing them down. This discovery, which garnered the 2011 Nobel Prize in physics, is generally thought to imply the existence of a "dark energy" that counteracts gravity on cosmic scales. Its nature is a profound mystery. About the only thing we understand about dark energy, physicists such as Michael Turner of the University of Chicago have long said, is its name.

"There is a tremendous mismatch between what we calculate [dark energy] ought to be and what we observe," Guth says. According to quantum theory, subatomic particles are constantly popping into existence and vanishing again in the vacuum of space, which should endow it with energy—but that vacuum energy, according to theoretical calculations, would be 120 orders of magnitude (a 1 followed by 120 zeroes) too large to explain the galaxy observations. The discrepancy has been a great source of embarrassment to physicists.

A multiverse could wipe the cosmic egg off their faces. On the bell curve of all possible universes spawned by inflation, our universe might just happen to be one of the few universes in which the dark energy is relatively lame. In others, the antigravity force might conform to physicists' expectations and be strong enough to rip all matter apart.

A multiverse might also explain away another embarrassment: the number of dimensions predicted by modern "superstring" theory. String theory describes subatomic particles as being composed of tiny strings of energy, but it requires there to be 11 dimensions instead of the four we actually observe. Maybe it's just describing all possible universes instead of our own. (It suggests there could be a staggeringly large number of possibilities—a 1 with 500 zeroes after it.)

Join the "multiverse club," Linde wrote in a March 9 review of inflationary cosmology, and what looks like a series of mathematical embarrassments disappears in a cloud of explanation. In a multiverse, there can be more things dreamt of in physicists' philosophy than happen to be found in our sad little heaven and earth.

Life, the Universe, and Everything

The multiverse may even help explain one of the more vexing paradoxes about our world, sometimes called the "anthropic" principle: the fact that we are here to observe it.

To cosmologists, our universe looks disturbingly fine-tuned for life. Without its Goldilocks-perfect alignment of the physical constants—everything from the strength of the force attaching electrons to atoms to the relative weakness of gravity—planets and suns, biochemistry, and life itself would be impossible. Atoms wouldn't stick together in a universe with more than four dimensions, Guth notes.

If ours was the only cosmos spawned by a Big Bang, these life-friendly properties would seem impossibly unlikely. But in a multiverse containing zillions of universes, a small number of life-friendly ones would arise by chance—and we could just happen to reside in one of them.

"Life may have formed in the small number of vacua where it was possible, in a multiverse," says Guth. "That's why we are seeing what we are seeing. Not because we are special, but because we can."


Learn more about the birth of our universe in our April issue.

Follow Dan Vergano on Twitter. 
ART BY MOONRUNNER DESIGN 

Tuesday, April 23, 2013

How to Build a Multiverse

From The Economist, a little lesson on "table-top astrophysics." Physicists are not able to bring black holes or white dwarfs to their labs, so they are recreating them at the molecular level to advance our knowledge of these phenomena.

How to build a multiverse


Small models of cosmic phenomena are shedding light on the real thing


Mar 16th 2013  |  From the Edition


THE heavens do not lend themselves to poking and prodding. Astronomers therefore have no choice but to rely on whatever data the cosmos deigns to throw at them. And they have learnt a lot this way. Thus you can even (see article) study chemistry in space that would be impossible in a laboratory. Some astronomers, though, are dissatisfied with being passive observers. Real scientists, they think, do experiments.

It is impossible—not to mention inadvisable—to get close enough to a star or a black hole to manipulate it experimentally. But some think it might be possible to make meaningful analogues of such things, and even of the universe itself, and experiment on those instead.

Ben Murdin of the University of Surrey, for example, has been making white dwarfs. A white dwarf is the stellar equivalent of a shrunken but feisty old-age pensioner. It has run out of fuel and is contracting and cooling as it heads towards oblivion—but taking its time about it. As they shrink white dwarfs pack a mass up to eight times the sun’s into a volume the size of Earth. A consequence of stuffing so much matter into so little space is that white dwarfs have powerful magnetic fields. Many aspects of a white dwarf’s mechanics, including how long it will last, are thought to depend on its magnetism. But it is hard to measure.

To make estimates, scientists examine the light a white dwarf emits for telltale patterns left by stellar ingredients like hydrogen. They then compare this spectrum with a theory, based on calculations from first principles, of how magnetic fields effect light emitted by hydrogen. The predictions agree with experiments up to the strongest fields mankind can muster—about 1,000 tesla, generated in a thermonuclear detonator. The problem is that the theory puts white dwarfs’ magnetic fields at 100,000 tesla or more, well beyond humanity’s reach.

Dr Murdin built his own little white dwarf to see if the theory looked good. It consists of a silicon crystal sprinkled with phosphorus atoms. A silicon atom has four electrons in its outer shell. In a crystal, all four are used to bind it to neighbouring atoms. Phosphorus has five outer electrons. Insert a phosphorus atom into the silicon lattice and you are left with an unused electron. Since phosphorus also has one more proton in its nucleus than silicon does, taken together the extra particles resemble a hydrogen atom: a single electron tethered to a single proton.

However, the extra electron is much less tightly held by the extra proton in this pseudo-hydrogen than it would be in real hydrogen. This weaker grasp means that it takes much less magnetism to make a given change in the pseudo-hydrogen’s spectrum than it would for real hydrogen. So when Dr Murdin placed the crystal in a 30-tesla magnet at Radboud University in the Netherlands (his lab in Guildford lacks the necessary kit), he was mimicking the conditions in a 100,000-tesla white dwarf. And the spectrum came out looking just the way the theory predicted.

A black hole in a bath…

Creating a star in a laboratory is small beer compared with creating a black hole. This is an object that is so massive and dense that not even light can flee its gravitational field. Looking inside one is therefore, by definition, impossible. All the more reason to try, says Silke Weinfurtner of the International School for Advanced Studies, in Trieste, Italy.

Dr Weinfurtner plans to make her black hole in the bath. The bath in question, properly called a flume, is a water-filled receptacle 3 metres by 1.5 metres and 50cm deep, across which carefully crafted trains of ripples can pass. In the middle of the tank is a plug hole. If the water going down the hole rotates faster than the ripples can propagate, the ripples which stray beyond the aqueous “event horizon” (a black hole’s point of no return) will not make it out. They are sucked down the drain.

Then the researchers will check whether the simulacrum affects water waves in a way analogous to that which general relativity predicts for light—itself a wave—approaching an astrophysical black hole. According to Albert Einstein’s theory, a region immediately outside the event horizon of a rotating black hole will be dragged round by the rotation. Any wave that enters this region but does not stray past the event horizon should be deflected and come out with more energy than it carried on the way in. To detect this super-radiant scattering, as the effect is called, Dr Weinfurtner will add fluorescent dye to the water and illuminate the surface waves with lasers. The waves, often no bigger than one millimetre, can then be detected using high-definition cameras.

Stefano Liberati, Dr Weinfurtner’s colleague in Trieste, reserves the greatest enthusiasm for another aspect of the experiment. It might, if the researchers are lucky enough, offer clues to the nature of space-time. Could the cosmic fabric be made up of discrete chunks, atoms of space if you like, rather than being continuous, as is assumed by relativity? This problem has perplexed physicists for decades. Many suspect black holes hold the answer, because they are sites where continuous relativity meets chunky quantum physics.

Waterborne holes serve as a proxy. Water is, after all, made up of just such discrete chunks: molecules of H₂O. As wavelengths fall—equivalent to rising energy—waves reach a point where the size of molecules may begin to influence how they behave. If Dr Weinfurtner and Dr Liberati observe some strange behaviour around their event horizons, theorists will be thrilled.

…and home-brewed universes

Even benchtop black holes, though, are nothing compared with the ambitions of Igor Smolyaninov of the University of Maryland. For Dr Smolyaninov wants to create entire universes.

The way light travels through the four dimensions of space-time is mathematically akin to how it moves through “metamaterial”. These are substances with features measured in nanometres, or billionths of a metre, which let them bend light in unusual ways. For example they can force light to skirt along the outside of an object, hiding it from view as if behind an invisibility cloak. Space-time, too, bends light, in ways that depend on how mass is distributed within it.

In principle, then, metamaterials ought to be able to mimic how light moves not just through the space-time scientists on Earth are familiar with, but also other possible space-times to which they do not, and never will, have access. Two years ago Dr Smolyaninov suggested an experiment with various metamaterials, corresponding to universes with different properties lashed together into a home-brewed multiverse. In a paper to be published inOptics Express, he and his colleagues report that they have succeeded.

Rather than fine-tune metamaterial to exact specifications, which is finicky and expensive, the researchers used nanoparticles of cobalt, which are relatively easy to get hold of, and suspended them in kerosene. They then applied a magnetic field which, thanks to cobalt’s ferromagnetic nature, arranged the particles into thin columns. In space-time terms the length of the columns is time and the two axes perpendicular to the length represent the three spatial dimensions in a real universe.

To build his multiverse, Dr Smolyaninov added slightly less cobalt to the kerosene, about 8% by volume, than was needed to maintain stable nanocolumns. Natural fluctuations in the density of the fluid then lead to the spontaneous erection of transient nanocolumns—equivalent to space-times popping up only to fizzle and re-emerge elsewhere in the multiverse. They could be detected by their effect on polarised light shone through the material.

Whether all this ingenuity unravels any cosmic truth is uncertain. Cliff Burgess, a theorist at Perimeter Institute for Theoretical Physics in Ontario, has his doubts. But he thinks that such experiments are nevertheless worth pursuing. “Like tap-dancing snakes,” he says, “the point is not that they do it well, it is that they do it at all.”

From the print edition: Science and technology

Monday, March 11, 2013

Brian Greene - Is Our Universe The Only Universe?


Physicist Brian Greene is the author of The Elegant Universe (Pulitzer finalist), The Fabric of the Cosmos, and The Hidden Reality (his most recent book). In this segment from the TED Radio Hour on NPR, Greene discusses some of the ideas in his latest book:
Is there more than one universe? In this visually rich, action-packed talk, Brian Greene shows how the unanswered questions of physics (starting with a big one: What caused the Big Bang?) have led to the theory that our own universe is just one of many in the "multiverse."
Enjoy.

Is Our Universe The Only Universe?

by NPR/TED STAFF
February 18, 2013

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TED Radio Hour
11 min 37 sec
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Part 4 of the TED Radio Hour episode Peering Into Space.
More From This Episode: Peering Into Space



About Brian Greene's TED Talk

Is there more than one universe? Physicist Brian Greene shows how the unanswered questions of physics (starting with a big one: What caused the Big Bang?) have led to the theory that our own universe is just one of many in the "multiverse."

About Brian Greene

Brian Greene is perhaps the best-known proponent of superstring theory, the idea that minuscule strands of energy vibrating in a higher dimensional space-time create every particle and force in the universe. Greene, a professor of physics and mathematics at Columbia University, has focused on unified theories for more than 25 years, and has written several best-selling and non-technical books on the subject including The Elegant Universe, a Pulitzer finalist, and The Fabric of the Cosmos—each of which has been adapted into a NOVA mini-series. His latest book, The Hidden Reality, explores the possibility that our universe is not the only universe.

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Sunday, February 24, 2013

Michael Hanlon - The World Next Door: Nine Theories of the Multiverse


From Aeon, Michael Hanlon gives us an overview of the "nine flavors" of the multiverse. The number comes from Brian Greene's The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos (2011) where he argues there no fewer than nine compatible versions of the multiverse. This article summarizes those flavors and adds some context.

World next door

Nine theories of the multiverse promise everything and more. But if reality is so vast and varied, where do we fit in?


by

String Theory suggests that our universe may be like a page in a book, stacked alongside tens of trillions of others. Those other realities would be right next to us now. Photo by the Esch Collection/Getty
String Theory suggests that our universe may be like a page in a book, stacked alongside tens of trillions of others. Those other realities would be right next to us now.  
Photo by the Esch Collection/Getty

Our understanding of the fundamental nature of reality is changing faster than ever before. Gigantic observatories such as the Hubble Space Telescope and the Very Large Telescope on the Paranal Mountain in Chile are probing the furthest reaches of the cosmos. Meanwhile, with their feet firmly on the ground, leviathan atom-smashers such as the Large Hadron Collider (LHC) under the Franco-Swiss border are busy untangling the riddles of the tiny quantum world.

Myriad discoveries are flowing from these magnificent machines. You may have seen Hubble’s extraordinary pictures. You will probably have heard of the ‘exoplanets’, worlds orbiting alien suns, and you will almost certainly have heard about the Higgs Boson, the particle that imbues all others with mass, which the LHC found this year. But you probably won’t know that (if their findings are taken to their logical conclusion) these machines have also detected hints that Elvis lives, or that out there, among the flaming stars and planets, are unicorns, actual unicorns with horns on their noses. There’s even weirder stuff, too: devils and demons; gods and nymphs; places where Hitler won the Second World War, or where there was no war at all. Places where the most outlandish fantasies come true. A weirdiverse, if you will. Most bizarre of all, scientists are now seriously discussing the possibility that our universe is a fake, a thing of smoke and mirrors.

All this, and more, is the stuff of the multiverse, the great roller-coaster rewriting of reality that has overturned conventional cosmology in the last decade or two. The multiverse hypothesis is the idea that what we see in the night sky is just an infinitesimally tiny sliver of a much, much grander reality, hitherto invisible. The idea has become so mainstream that it is now quite hard to find a cosmologist who thinks there’s nothing in it. This isn’t the world of the mystics, the pointy-hat brigade who see the Age of Aquarius in every Hubble image. On the contrary, the multiverse is the creature of Astronomers Royal and tenured professors at Cambridge and Cornell.

First, some semantics. The old-fashioned, pre-multiverse ‘universe’ is defined as the volume of spacetime, about 90 billion light years across, that holds all the stars we can see (those whose light has had enough time to reach us since the Big Bang). This ‘universe’ contains about 500 sextillion stars — more than the grains of sand on all the beaches of Earth — organised into about 80 billion galaxies. It is, broadly speaking, what you look up at on a clear night. It is unimaginably vast, incomprehensibly old and, until recently, assumed to be all that there is. Yet recent discoveries from telescopes and particle colliders, coupled with new mathematical insights, mean we have to discard this ‘small’ universe in favour of a much grander reality. The old universe is as a gnat atop an elephant in comparison with the new one. Moreover, the new terrain is so strange that it might be beyond human understanding.

That hasn’t stopped some bold thinkers from trying, of course. One such is Brian Greene, professor of physics and mathematics at Columbia University in New York. He turned his gaze upon the multiverse in his latest book, The Hidden Reality (2011). According to Greene, it now comes in no fewer than nine ‘flavours’, which, he says, can ‘all work together’.

The simplest version he calls the ‘quilted multiverse’. This arises from the observation that the matter and energy we can see through our most powerful telescopes have a certain density. In fact, they are just dense enough to permit a gravitationally ‘flat’ universe that extends forever, rather than looping back on itself. We know that a repulsive field pervaded spacetime just after the Big Bang: it was what caused everything to fly apart in the way that it did. If that field was large enough, we must conclude that infinite space contains infinite repetitions of the ‘Hubble volume’, the volume of space, matter and energy that is observable from Earth.
If this is correct, there might — indeed, there must — be innumerable dollops of interesting spacetime beyond our observable horizon. There will be enough of these patchwork, or ‘pocket’, universes for every single arrangement of fundamental particles to occur, not just once but an infinite number of times. It is sometimes said that, given a typewriter and enough time, a monkey will eventually come up with Hamlet. Similarly, with a fixed basic repertoire of elementary particles and an infinity of pocket universes, you will come up with everything.

In such a case, we would expect some of these patchwork universes to be identical to this one. There is another you, sitting on an identical Earth, about 10 to the power of 10 to the power of 120 light years away. Other pocket universes will contain entities of almost limitless power and intelligence. If it is allowed by the basic physical laws (which, in this scenario, will be constant across all universes), it must happen. Thus there are unicorns, and thus there are godlike beings. Thus there is a place where your evil twin lives. In an interview I asked Greene if this means there are Narnias out there, Star Trek universes, places where Elvis got a personal trainer and lived to his 90s (as has been suggested by Michio Kaku, a professor of theoretical physics at the City University of New York). Places where every conscious being is in perpetual torment. Heavens and hells. Yes, it does, it seems. And does he find this troubling? ‘Not at all,’ he replied. ‘Exciting. Well, that’s what I say in this universe, at least.’

The quilted multiverse is only the beginning. In 1999 in Los Angeles, the Russian émigré physicist Andrei Linde invited a group of journalists, myself included, to watch a fancy computer simulation. The presentation illustrated Linde’s own idea of an ‘inflationary multiverse’. In this version, the rapid period of expansion that followed the Big Bang did not happen only once. Rather, like Trotsky’s hopes for Communism, it was a constant work in progress. An enormous network of bubble universes ensued, separated by even more unimaginable gulfs than those that divide the ‘parallel worlds’ of the quilted multiverse.

Here’s another one. String Theory, the latest attempt to reconcile quantum physics with gravity, has thrown up a scenario in which our universe is a sort of sheet, which cosmologists refer to as a ‘brane’, stacked up like a page in a book alongside tens of trillions of others. These universes are not millions of light years away; indeed, they are hovering right next to you now.

That doesn’t mean we can go there, any more than we can reach other universes in the quantum multiverse, yet another ‘flavour’. This one derives from the notion that the probability waves of classical quantum mechanics are a hard-and-fast reality, not just some mathematical construct. This is the world of Schrödinger’s cat, both alive and dead; here, yet not here. Einstein called it ‘spooky’, but we know quantum physics is right. If it wasn’t, the computer on which you are reading this would not work.

The ‘many worlds’ interpretation of quantum physics was first proposed in 1957 by Hugh Everett III (father of Mark Everett, frontman of the band Eels). It states that all quantum possibilities are, in fact, real. When we roll the dice of quantum mechanics, each possible result comes true in its own parallel timeline. If this sounds mad, consider its main rival: the idea that ‘reality’ results from the conscious gaze. Things only happen, quantum states only resolve themselves, because we look at them. As Einstein is said to have asked, with some sarcasm, ‘would a sidelong glance by a mouse suffice?’ Given the alternative, the prospect of innumerable branching versions of history doesn’t seem like such a terrible bullet to bite.
Stranger still is the holographic multiverse, which implies that ‘our world’ — not just stars and galaxies but you and your bedroom, your career problems and last night’s dinner — are mere flickers of phenomena taking place on an inaccessible plane of reality. The entire perceptible realm would amount to nothing more than shapes in a shadow theatre. This sounds like pure mysticism; indeed, it sounds almost uncannily like Plato’s allegory of the cave. Yet it has some theoretical support: Stephen Hawking relies on the idea in his solution to the Black Hole information paradox, which is the riddle of what happens to information destroyed as it crosses the Event Horizon of a dark star.
String theory affords other possibilities, and yet more layers of multiverse. But the strangest (and yet potentially simplest) of all is the idea that we live in a multiverse that is fake. According to an argument first posited in 2001 by Nick Bostrom, professor of philosophy at the University of Oxford, there is a non-trivial probability that we, our world, and even the vast extensions of spacetime that we saw in the first multiverse scenarios, are no more than a gigantic computer simulation.

The idea that what we perceive as reality is no more than a construct is quite old, of course. The Simulation Argument, as it is called, has features in common with the many layers of reality posited by some traditional Buddhist thinking. The notion of a ‘pretend’ universe, on the other hand, crops up in fiction and film — examples include the Matrix franchise and The Truman Show (1998). The thing that makes Bostrom’s idea unique is the basis on which he argues for it: a series of plausible assumptions, plus a statistical calculation.

In essence, the case goes like this. If it turns out to be possible to use computers to simulate a ‘universe’ — even just part of one — with self-aware sentient entities in it, the chances are that someone, somewhere, will do this. Furthermore, as Bostrom explained it to me, ‘Look at the way our computer simulations work. When we run a simulation of, say, the weather or of a nuclear explosion [the most complex computer simulations to date performed], we do not run them once, but many thousands, millions — even billions — of times. If it turns out that it is possible to simulate — or, more correctly, generate — conscious awareness in a machine, it would be surprising if this were done only once. More likely it would be done countless billions of times over the lifetime of the advanced civilisation that is interested in such a project.’

If we start running simulations, as we soon might, given our recent advances in computing power, this would be very strong evidence that we ourselves live in a simulation. If we conclude that we are, we have some choices. I'll say more on those below.

First, we come to the most bizarre scenario of all. Brian Greene calls it the ‘ultimate multiverse’. In essence, it says that everything that can be true is true. At first glance, that seems a bit like the quilted multiverse we met earlier. According to that hypothesis, all physical possibilities are realised because there is so much stuff out there and so much space for it to do things in.
The ultimate multiverse supercharges that idea: it says that anything that is logically possible (as defined by mathematics rather than by physical reality) is actually real. Furthermore, and this is the important bit, it says that you do not necessarily need the substrate of physical matter for this reality to become incarnate. According to Max Tegmark, professor of physics at the Massachusetts Institute of Technology, the ‘Mathematical Universe Hypothesis’ can be stated as follows: ‘all structures that exist mathematically also exist physically‘. Tegmark uses a definition of mathematical existence formulated by the late German mathematician David Hilbert: it is ‘merely the freedom from contradiction’. Hence, if it is possible, it exists. We can allow unicorns but not arbitrary, logic-defying magic.

What does all this mean? If we live in a world of infinite possibilities existing across numerous dimensions, what is the point of trying to make sense of any of it? Does any of it have the slightest bearing on how we ought to live?

For the most part, scientists have no answer to these questions, except to repeat Churchill’s maxim to ‘keep buggering on’. But some have come up with tentative suggestions. Robin Hanson, an economist at George Mason University, has written several commentaries on Bostrom’s simulation thesis. His conclusions are rather depressing: ‘If our descendants prefer their simulations to be entertaining, all else equal, then you should want you and the events around you to be entertaining as well, all else equal … Be funny, outrageous, violent, sexy, strange, pathetic, heroic ... in a word “dramatic”.’

The main thing is to make your story so compelling that people want to simulate you again. Forget being good: what does morality mean in a simulated universe anyway? Instead, be interesting — be Hitler, Jesus or Princess Diana, because it magnifies the chances that you will be reincarnated the next time the universe boots up, or be brought back when the audience decides your character is too interesting to kill off.

Perhaps the most extraordinary thing about all these arguments is how drily respectable they are. Martin Rees, the British Astronomer Royal, is a fully paid-up member of the multiverse club. His main argument is that ‘our’ universe appears to have been suspiciously fine-tuned to allow the existence of life, the so-called anthropic principle. Change any of the basic parameters even slightly — the strength of the Strong Nuclear Force, or the gravitational constant — and you end up with a dull universe that is either a sea of radiation or a black hole.

There are those who see here the hand of god. Others say that the anthropic principle is just a special case of selection bias. Think of a very fat, very short man who walks into a shop looking for a suit. If it’s a small shop, he would be right to be surprised if he found a suit that fitted. But if the shop was big and had thousands of suits, of almost all conceivable dimensions, there would be no surprise at all. Similarly, we should not be amazed to discover we live in a universe that can contain life if there were a lot of universes to choose from.

Some accuse the multiversers of technical-mysticism, of putting their faith in claims that are fundamentally unfalsifiable. To confirm string theory, for example, would require a particle accelerator the size of Betelgeuse. But those who argue that this ‘isn’t science’ are on the back foot. It is just possible that the Large Hadron Collider will detect direct evidence of the extra dimensions needed by string theory, for instance, and provide hints as to whether ‘our’ gravity is the weak remnant of a force operating at far greater strength in another universe. This could happen within the decade, not in some theoretical Star Trek future. Meanwhile, better telescopes could resolve the issue of whether our universe is really ‘flat’ and infinite.

We should not be surprised by the multiverse. Every time we have taken a look at the world around us, it has expanded. Copernicus realised that the Earth was not the centre of creation. Edwin Hubble realised that the Milky Way was just one galaxy among billions. Now we suspect that ‘reality’ is, in fact, something so magnificently vast that we struggle even to comprehend the parameters of how to describe it. Brian Greene finds this amazing and, clearly, rather wonderful.

So, from my own position of profound befuddlement, do I. But I also find it rather troubling. There are things missing from the multiverse: an intelligible place for consciousness, for one. Then there is the sense that, in a world where all possibilities become certainties and anything that can happen does happen, moral purpose is even more elusive than in the old-fashioned singular universe. If your evil twin is out there (which, in an infinite ‘flat’ universe, he or she certainly is), what does it matter what you do in your bit of eternity? For half a millennium science has been chipping away at the idea that humanity is central and unique. The multiverse replaces the chisel with a wrecking ball.

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