An interesting talk on the evolutionary precursors of morality, mirror neurons and more.Part One:
Taken from Beyond Belief 2008.
Part Two:
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Tuesday, July 07, 2009
Marco Iacoboni on Empathy and Fairness
Nice two-part video.
Part Two:
Part Two:
Integral Enlightenment - The Future of God: Spirituality in an Evolving Universe
A cool Integral Enlightenment podcast for download.
The Future of God: Spirituality in an Evolving Universe
In this reflection on the purpose of life in the 21st century, Integral Enlightenment founder Craig Hamilton calls us to wholeheartedly embrace a path of conscious evolution, not simply for our own happiness, but as our contribution to the further evolution of Life and Spirit.
Click Here to download this audio.
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I, We, and It - the Good, the True and the Beautiful by Ken Wilber
An old one but a good one.
I, We, and It - the Good, the True and the Beautiful by Ken Wilber
Download audio file [Play]
- Artist: Ken Wilber
- Title: I, We, and It - the Good, the True and the Beautifu
- Album: Kosmic Consciousness - 1
- Length: 19:00 minutes (26.11 MB)
- Format: MP3 Stereo 44kHz 192Kbps (CBR)
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Robert Augustus Masters - What Matters About Matter
Nice new article from Robert Masters in this month's newsletter.
WHAT MATTERS ABOUT MATTER
Matter is more than what we typically think of as matter. There’s more to it than meets the eye, more to it than its density and mass, more to it than the popularization of it as but dumb putty to be molded or manipulated by an overseeing mind.
We commonly take as a given the notion of mind over matter, but rarely consider the notion of mind as matter, or matter as externalized mind.
Matter matters.
Though denser than mind, soul, or spirit, matter is not necessarily lesser than them, because it fundamentally is just the outside-ness of them crystallized into relative solidity, and without an outside, what can we say about an inside?
We have to be especially careful with language here, for what’s outside typically (or conventionally) contains what’s inside, but in the case of matter, what’s outside is contained by what’s inside, in the sense that a greater depth contains a lesser depth.
And so the body does not contain the soul (our individualized essence), but the soul contains the body — and in a even deeper sense, the body does not contain the soul, but rather is an expression of the soul. What we truly are is not making an appearance in a body, but as a body.
So let us cast a kinder eye on matter, and cease viewing it as a mere sheath or sensory integument for (or impediment to realizing) higher realities, for the densified outside-ness that characterizes it constitutes not a literal container or housing project for what’s inside, but rather a precipitated extension of what’s inside, providing a medium for that interiority or central depth to relate to what lies outside it.
Matter, as part of its job description, does the dirty work, and doesn’t really mind, because that’s its nature. Someone has to take out the garbage and build the highways. Grunt work matters, and as a matter-of-fact needs to be honored as such.
Mind is itself a kind of mass-less matter, the interiority of which could be called soul, or the individualized core of what we truly are. Soul has less of a problem with matter than does mind, because it has more of a view. The deeper inside we are, the higher our view. What’s further up the mountain can see more than what’s at lower elevations.
Inside and outside are but inseparable sides of a primal geography, together on their knees before the same old yet everfresh Mystery. When inside and outside are lovers, we know a love that cannot fail, a love that is both ocean and sail.
Once again poetry has me by the jugular, and I don’t mind at all. There’s a part in The Fountain (see my review in my January 2007 Newsletter) when the Mayan priest kneels, leans back his head, and bares his throat, inviting the transfigured conquistador to cut it, so that he can be one with the Sacred. It wasn’t just a romanticized primitive moment, but rather a full-blooded signifier of extraordinary awe and sacrifice, the sort of sacrifice through which we die into a deeper Life.
Taking in a scene like this, really feeling and absorbing it, making it our own until it’s not so much ours as it is us, generates a wondrously sobering and illuminating leap through various hoops of mind, until there’s no everyday mind left, no mapmaker, no supplier of meaning, nothing but What-Really-Matters.
My sentences are erasing themselves almost as fast I type them. They look back and see nothing. I look back and see everything. All of it is there, both outside and inside me, for all of it was necessary to bring “me” into being, even though it did not all arise just to bring me into being, except in the narcissistic outback of my egoity.
Yes, I matter, but no more than you. Of course, my mind disagrees, but that’s its nature. Matter keeps arising, keeps passing, and through it I live, we live, whatever we may be.
I’m tempted to look back at the beginning of this essay, but don’t dare, not because I’ll be turned to stone, and not because my beloved will die, but because this wild flow, this unkempt opening and spilling, is more me than the me writing this, which amounts to nothing more than me letting what I’m writing outwrite me.
Now inside and outside have traded places, and no one’s making a fuss about it. What is most deeply within contains all that is outside it. Reality’s Möbius nature — one infinite surface of infinite depth — takes all the mappings of inside and outside, interiority and exteriority, higher and lower, horizontality and verticality, and makes light of it.
There is, however, no leveling or flattening of differences here, no homogenizing of distinctions, no cosmic rolling pin turning it all into one gigantic plain, like some ultra-great pizza awaiting its toppings and corresponding appetites.
Matter matters. But what is matter? Solid stuff? Concretized mind? A torte of atomic and subatomic particles/waves/potentialities, dense and elusive and intricate enough to make our mind lick its lips?
Matter is dense, but its density vanishes as we get closer and closer to it. Get really close to matter, and what you will see is gravity and light in endless embrace, creating in their wake something that keeps evolving to — and perhaps also beyond — the point of knowing that it is evolving.
We are not only that something, but also something more, something that cannot be imagined, something that is neither inside nor outside.
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Monday, July 06, 2009
George Lakoff - Unconscious Imaginitive Perception
Sorry, but I can't give you a page number for this passage from Philosophy in the Flesh because it' on my Kindle DX, but I can tell you that it's locations 428-35 (Chapter 3).
As you read this short passage, try to contemplate the complexity of what our brains do without us even being aware of what is happening.
We use spatial-relations concepts unconsciously, and we impose them via our perceptual and conceptual systems. We just automatically and unconsciously "perceive" one entity as in, on, or across from another. However, such perception depends on an enormous amount of automatic unconscious mental activity on our part. For example, to see a butterfly in the garden, we have to project a nontrivial amount of imagistic structure onto a scene. We have to conceptualize the boundaries of the garden as a three-dimensional container with an interior that extends into the air. We also have to locate the butterfly as a figure (or trajector) relative to that conceptual container, which serves as a ground (or landmark). We perform such complex, though mundane, acts of imaginative perception during every moment of our waking lives.
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What Skepticism Reveals about Science - Michael Shermer
Michael Shermer is his usual entertaining self.
What Skepticism Reveals about Science
A skeptic's journey for truth in science
In a 1997 episode of The Simpsons entitled “The Springfield Files”—a parody of X-Files in which Homer has an alien encounter in the woods (after imbibing 10 bottles of Red Tick Beer)—Leonard Nimoy voices the intro as he once did for his post-Spock run on the television mystery series In Search of...: “The following tale of alien encounters is true. And by true, I mean false. It’s all lies. But they’re entertaining lies, and in the end isn’t that the real truth? The answer is no.”
No cubed. The postmodernist belief in the relativism of truth, coupled to the clicker culture of mass media where attention spans are measured in New York minutes, leaves us with a bewildering array of truth claims packaged in infotainment units. It must be true—I saw it on television, at the movies, on the Internet. The Twilight Zone, The Outer Limits, That’s Incredible, The Sixth Sense, Poltergeist, Loose Change, Zeitgeist the Movie. Mysteries, magic, myths and monsters. The occult and the supernatural. Conspiracies and cabals. The face on Mars and aliens on Earth. Bigfoot and Loch Ness. ESP and PSI. UFOs and ETIs. JFK, RFK and MLK—alphabet conspiracies. Altered states and hypnotic regression. Remote viewing and astroprojection. Ouija boards and Tarot cards. Astrology and palm reading. Acupuncture and chiropractic. Repressed memories and false memories. Talking to the dead and listening to your inner child. Such claims are an obfuscating amalgam of theory and conjecture, reality and fantasy, nonfiction and science fiction. Cue dramatic music. Darken the backdrop. Cast a shaft of light across the host’s face. The truth is out there. I want to believe.
What I want to believe based on emotions and what I should believe based on evidence does not always coincide. And after 99 monthly columns of exploring such topics (this is Opus 100), I conclude that I’m a skeptic not because I do not want to believe but because I want to know. I believe that the truth is out there. But how can we tell the difference between what we would like to be true and what is actually true? The answer is science.
Science begins with the null hypothesis, which assumes that the claim under investigation is not true until demonstrated otherwise. The statistical standards of evidence needed to reject the null hypothesis are substantial. Ideally, in a controlled experiment, we would like to be 95 to 99 percent confident that the results were not caused by chance before we offer our provisional assent that the effect may be real. Failure to reject the null hypothesis does not make the claim false, and, conversely, rejecting the null hypothesis is not a warranty on truth. Nevertheless, the scientific method is the best tool ever devised to discriminate between true and false patterns, to distinguish between reality and fantasy, and to detect baloney.
The null hypothesis means that the burden of proof is on the person asserting a positive claim, not on the skeptics to disprove it. I once appeared on Larry King Live to discuss UFOs (a perennial favorite of his), along with a table full of UFOlogists. King’s questions for other skeptics and me typically miss this central tenet of science. It is not up to the skeptics to disprove UFOs. Although we cannot run a controlled experiment that would yield a statistical probability of rejecting (or not) the null hypothesis that aliens are not visiting Earth, proof would be simple: show us an alien spacecraft or an extraterrestrial body. Until then, keep searching and get back to us when you have something. Unfortunately for UFOlogists, scientists cannot accept as definitive proof of alien visitation such evidence as blurry photographs, grainy videos and anecdotes about spooky lights in the sky. Photographs and videos can be easily doctored, and lights in the sky have many prosaic explanations (aerial flares, lighted balloons, experimental aircraft, even Venus). Nor do government documents with redacted paragraphs count as evidence for ET contact, because we know that governments keep secrets for national security reasons. Terrestrial secrets do not equate to extraterrestrial cover-ups.
Read the rest of the article.
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The Difficult Questions of ‘Personhood’ by Mike Treder
Being a human and being person may not be the same thing.
The Difficult Questions of ‘Personhood’
Mike TrederMike Treder
Ethical Technology
Posted: Jul 2, 2009
Every human is a person, right? And anyone we call a person must be a human, correct?
Well, no, not necessarily.
According to Merriam-Webster’s Online Dictionary, ‘person’ means: 1) human, individual.
That seems as if ‘human’ and ‘person’ should be completely overlapping and identical sets, like this:
But many ethicists, particularly progressive bioethicists, say that for both legal and ethical reasons it is advisable that we sharpen our common definitions of ‘person’ and ‘human’ so that they do not entirely overlap. For example, profoundly disabled humans—whether badly brain-damaged or mentally handicapped to a severe degree—might not then be designated as ‘persons’ by this refined definition.
In that case, the sets would not totally cohere and would look like this:
The observant reader may wonder why there is so much extra blue space in the Persons set on the chart above. That’s because I’m going to suggest that several other species beyond Homo sapiens should be considered for inclusion under the definition of ‘persons’.
From an article at Wired Science:
As a population of West African chimpanzees dwindles to critically endangered levels, scientists are calling for a definition of personhood that includes our close evolutionary cousins.
Just two decades ago, the Ivory Coast boasted a 10,000-strong chimpanzee population, accounting for half of the world’s population. According to a new survey, that number has fallen to just a few thousand.
News of such a decline, published today in Current Biology, would be saddening in any species. But should we feel more concern for the chimpanzees than for another animal — as much concern, perhaps, as we might feel for other people?
“They are a people. Non-human, but definitely persons,” said Deborah Fouts, co-director of the Chimpanzee and Human Communication Institute. “They haven’t built a rocket ship to the moon. But we’re not that different.”
Fouts is one of a growing number of scientists and ethicists who believe that chimpanzees — as well as orangutans, bonobos and gorillas, a group colloquially known as great apes — ought to be considered people.
It’s a controversial position. If being a person requires being human, then chimpanzees, our closest primate relative, are still only 98 percent complete. But if personhood is defined more broadly, chimpanzees may well qualify. They have self-awareness, feelings and high-level cognitive powers. Hardly a month seems to pass without researchers finding evidence of behavior thought to belong solely to humans.
Some even suggest that chimpanzees and other great apes should be granted human rights.
If you accept the proposal that great apes ought to be regarded as persons, then our chart looks like this:
Note that the set of Great Apes does not fall entirely within the set of Persons. That’s because it seems logical that if some humans are excluded on the basis of their severe handicaps, then some great apes would fall outside the appropriate definition of personhood for similar reasons.
Another group of animals also might deserve consideration as persons, namely Cetacea (whales, dolphins, and porpoises).
From an earlier article at Wired Science:
As the annual International Whaling Commission meeting stumbles to a close, unable to negotiate a compromise between whaling opponents and people who’ve killed more than 40,000 whales since 1985, scientists say these aquatic mammals are more than mere animals. They might even deserve to be considered people.
Not human people, but as occupying a similar range on the spectrum as the great apes, for whom the idea of personhood has moved from preposterous to possible. Chimpanzees, gorillas and bonobos possess self-awareness, feelings and high-level cognitive powers. According to a steadily gathering body of research, so do whales and dolphins.
In fact, their capacities could be even more ancient than our own, dating to an evolutionary explosion in brain size that took place millions of years before the last common ancestor of the great apes existed.
“If an alien came down anytime prior to about 1.5 million years ago to communicate with the ‘brainiest’ animals on Earth, they would have tripped over our own ancestors and headed straight for the oceans to converse with the dolphins,” said Lori Marino, an evolutionary neurobiologist at the Yerkes National Primate Research Center.
The idea of whale personhood makes all the more haunting the prospect that Earth’s cetaceans, many of whom were hunted to the brink of extinction in the late 19th and early 20th centuries, are still threatened.
Now we have three sets overlaying the Personhood set:
But we’re not done yet.
Transhumanists expect that at some point during this century—possibly within just a few decades—a new set of sentient beings, not entirely biological in origin, will emerge. These ‘cyborgs’ might include robots with artificial brains, humans with significant cognitive or other enhancements, or even computer-based lifeforms. Perhaps not all cyborgs will deserve to be defined as persons, but certainly some will. Thus we have:
And, finally, if we go back to Merriam-Webster’s Online Dictionary, where we began, we learn that another definition of ‘person’ is: 6) one (as a human being, a partnership, or a corporation) that is recognized by law as the subject of rights and duties.
So, we have to include as persons not just humans, great apes, cetaceans, and cyborgs, but also corporations:
Wow, this is getting pretty complicated. What are the implications of these expanded and revised boundaries of ‘personhood’? What does it mean legally and ethically? How might it affect social, environmental, and economic policies? Moreover, what about the possibility—maybe the likelihood—that humans could choose in the next several decades to ‘uplift’ some of our animal cousins, using science and technology to give them greatly increased intelligence?
To answer all these questions would go well beyond the scope of one short blog article. It might be better, in fact, to convene a meeting of scholars and interested stakeholders to debate and discuss the topic and hopefully to find some consensus.
That’s precisely what we intend to do. Stay tuned over the new few months for more information about a proposed workshop on Personhood, to be organized by the Institute for Ethics and Emerging Technologies. It should prove very interesting.
Mike Treder is the Managing Director of the IEET, and former Executive Director of the non-profit Center for Responsible Nanotechnology.
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You Are Who You Are by Default
This is an interesting article from Science News that suggests that our brain is creating our sense of identity behind the scenes.
You Are Who You Are by Default
It may be off when you’re on, but the brain network behind daydreams and a sense of self is no slackerJuly 18th, 2009; Vol.176 #2 (p. 16)Wandering and wondering The brain's default mode network -- a series of connected areas that work hardest when most of the brain is at rest -- is active during daydreaming and mind-wandering. Many scientists believe the default network has two major hubs, one in the posterior cingulate cortex with the precuneus and one in the medial prefrontal cortex (shown above). Network overlay: Olaf Sporns/Indiana Univ. (modified by J. Korenblat); Brain photo: Omikron/photoresearchersYou may not be riding the latest social wave on Facebook or MySpace, or tweeting your every impulse to fans on Twitter. But your brain is hooked on networking.
Vision works because different brain regions link up to connect the dots of light and color into a meaningful picture of the world. Language depends on networks of neural circuitry that make sense of the words you hear or see and that help you generate your side of the conversation. Networks of nerves control the motion of your muscles, allowing you to move smoothly and, when necessary, swiftly.
Networks are the “in” thing for brain scientists, as surely as they have been for online social butterflies.
Scientists learn about the brain’s networks by asking people to perform all sorts of mental acrobatics — interpreting optical illusions, solving riddles, taking tests of mental or muscular skills. But some neuroscientists think they can learn even more about the brain by asking volunteers to just lie back, close their eyes and let their minds wander.
Such unstructured journeys of the mind — be they planning tonight’s dinner, thinking about that meeting at work and what your boss said afterward, debating whether to drive or fly for your next vacation, or recalling that day in your childhood when you first sat in your new tree house listening to birds chirp —turn out to offer clues about one of the most important, mysterious and well-connected networks of all. It’s called the default mode network, and it’s responsible for what the brain does when it is doing nothing in particular. It’s the brain’s core, both physically and mentally, and it’s better connected to the brain’s system of circuits than Kevin Bacon is to movie stars.
“I think the default mode network is the most exciting thing that has happened in cognitive neuroscience in quite some time,” says Peter Fransson, a neuroscientist at the Karolinska Institute in Stockholm.
Default brain settings may lead to daydreaming and mind-wandering, but the network also conducts serious business. Neuroscientists still hotly debate the network’s exact functions, however. Among its jobs may be running life simulations, providing a sense of self and maintaining crucial connections between brain cells. A few researchers doubt the network is anything special at all.
But evidence suggests that a malfunctioning default network is involved in diseases and disorders as diverse as Alzheimer’s disease, autism, depression, post-traumatic stress disorder, Tourette syndrome, amyotrophic lateral sclerosis, schizophrenia and attention-deficit/hyperactivity disorder.
Busy behind the scenes
Despite its laid-back name, which neuroscientist Marcus Raichle coined in a 2001 paper, the default mode network is one of the hardest-working systems in the brain. It was discovered accidentally by researchers watching the activity of brains at work on various tasks.
Neuroscientists use PET (short for positron emission tomography) and functional MRI scanners to image and gauge brain activity. To tell which areas of the brain become more active during a mental task, scientists compare brain activity during the task with activity when the person is at rest, either with eyes closed or while staring at a dot or cross. Raichle, of Washington University in St. Louis, and others saw that every time a person engaged in a mental activity such as memorizing a list of words, a collection of brain regions consistently decreased activity compared with their resting levels. Only when people recall autobiographical memories or imagine alternative situations is the network more active than it is at rest, scientists have since found. (In this context, “rest” refers to a state in which the brain is not engaged in a mental task but is still monitoring the body and the world around it.) Raichle hypothesized that the network is more active when the brain is at rest and has to dial back its activity to let people concentrate on specific tasks.
Michael Greicius, a neurologist and neuroscientist at the Stanford School of Medicine, put the resting part of Raichle’s theory to the test. Greicius and his colleagues measured brain activity while volunteers had their eyes closed and thought of nothing in particular. The team used a technique called functional connectivity MRI to reveal correlations in activity in different brain areas. The group reported in 2003 that blood flow in parts of the brain implicated in the default network rises and falls like the tides — in slow but synchronized waves.
Network in syncAt top, fMRI images show areas of the brain that coordinate activity when people are thinking about nothing in particular. The left image shows the outside of a left-facing brain. The right image shows the inner surface of one hemisphere of a right-facing brain. Activity in the two major hubs of the default network (indicated by yellow and orange arrows) rises and falls in time with each other, as seen on a plot of those fluctuations below. Courtesy of M. RaichleThose coordinated parts of the brain — with cumbersome names such as the medial prefrontal cortex, posterior cingulate cortex, retrosplenial cortex, precuneus, inferior parietal lobe and hippocampus — are located mostly along the crevice separating the brain’s hemispheres, and on each lobe behind and above the ears. Researchers don’t agree on all the components of the default network, but consensus is growing that it has two major hubs: the posterior cingulate cortex, or PCC, with the precuneus, and the medial prefrontal cortex.
Functions ascribed to those two areas may give clues to what the default network is good for. The medial prefrontal cortex is involved in imagining, thinking about yourself and “theory of mind,” which encompasses the ability to figure out what others think, feel or believe and to recognize that other people have different thoughts, feelings and beliefs from you. The precuneus and PCC are involved in pulling personal memories from the brain’s archives, visualizing yourself doing various activities and describing yourself.
Together, these hubs give you a sense of who you are. Their prominence in the network has led some researchers to propose that the function of the default mode is to allow you to internally explore the world and your place in it, so you can plot future actions, including contingency plans for various scenarios you might encounter.
The network that never sleeps
Some scientists quibble with the name, but Fransson says the network really is the brain’s default. Peter Williamson, a psychiatrist at the University of Western Ontario in London, Canada, agrees.
“You don’t even have to be conscious for it to be apparent,” he says.
Slow yet coordinated fluctuations in activity bind the network together. The syncopations continue even while people are asleep, under anesthesia or in comas. But it is unlikely that such activity reflects ongoing conscious processing, Greicius contends. The fluctuations that move through the network are incredibly slow, he says, with one cycle every 15 to 20 seconds. Most conscious thought happens in split seconds, so it is more likely that the plodding pulses are for “subconscious synapse maintenance,” he says.
Synapses are the connections between neurons where cell-to-cell communication takes place. When two neurons stop “talking” to each other, connections between them can be severed. Greicius thinks the low-level fluctuations in the network help keep the neurons in contact, sort of the brain-cell equivalent of Facebook status updates.
While it is good to stay connected, reverting to default isn’t always helpful. The default mode network sometimes stirs during monotonous tasks, drawing away a person’s attention. Such reactivation of the network predicted errors up to 30 seconds before a person made a mistake, Vince Calhoun of the MIND Research Network in Albuquerque and colleagues reported in 2008 in the Proceedings of the National Academy of Sciences. And a study published May 26 in that journal, by Kalina Christoff of the University of British Columbia in Vancouver, Canada, and colleagues, shows that not only is the default network involved in mind-wandering, it also distracts executive areas of the brain, so that people aren’t even aware that their minds have wandered off task.
Psychiatric connections
Researchers are also studying how defects in the coordination between different parts of the default network may contribute to psychiatric disorders. Calhoun, an electrical engineer at the University of New Mexico, and colleagues at other institutions studied network activity during a memory task in 115 people with schizophrenia and 130 healthy people. Some subnetworks within the default mode network had trouble disengaging in people with schizophrenia, impairing their ability to focus on the task, the team reported online May 11 in Human Brain Mapping.
Alzheimer's overlaps default networkAlzheimer's disease appears to particularly affect brain areas involved in the default network. At left, two views of the brain show areas activated (orange) when a healthy person recalls personal memories. Amyloid plaques characteristic of Alzheimer's accumulate (red) and the brain atrophies (blue) in some of the same areas, as shown in scans of people with dementia (middle and right). R.L. Buckner et al./Annals NY Academy of Science 2008, reprinted with permission of Blackwell Publishing LTD; M. Raichle (both)People with schizophrenia also have faster cycles of activity in their default networks during a resting state than healthy people do, Calhoun and another group of colleagues reported in the March 2007 American Journal of Psychiatry.
Williamson and colleagues, meanwhile, have shown that the default network’s connections with other parts of the brain may be important in determining who develops PTSD after a traumatic event. People who have been traumatized can become numb and lose their sense of self, Williamson says. The researchers examined default networks in women who developed PTSD after trauma in childhood. The study found altered levels of connectivity among parts of the default network as well as between the network and other parts of the brain. The findings, published in May in the Journal of Psychiatry & Neuroscience, could indicate that trauma creates disturbances in the network’s ability to create a sense of self.
The default network may also be the launching point for Alzheimer’s disease’s assault on the brain. The characteristic plaques of the disease deposit preferentially in the brain regions most associated with the network, studies have shown. And Greicius and his colleagues reported online last year in the June 2008 PLoS Computational Biology that activity in the default network is affected by the disease.
At least one study suggests that the default network may be vulnerable to Alzheimer’s disease decades before symptoms or plaques show up. Young people who carry a genetic risk factor for the disease have more activity in the default network, particularly in the hippocampus, than young people who don’t have the genetic risk, researchers from Oxford University and Imperial College in England reported in the April 28 Proceedings of the National Academy of Sciences. The authors say the study provides evidence for the theory that the default network’s constantly high activity eventually burns it out, leaving it vulnerable to Alzheimer’s disease.
Greicius says he isn’t a fan of this “use it and lose it” theory. Other networks in the brain also burn a lot of energy, even at rest, but they don’t fall prey to Alzheimer’s disease. Instead, Alzheimer’s and four other neurodegenerative diseases each target a different brain network, Greicius and colleagues including William Seeley of the University of California, San Francisco discovered. The results, published April 16 in Neuron, could mean that neurons that fire together die together. The researchers don’t yet understand why. It could be that when a neuron dies, its silence triggers death in neighboring neurons, or neuron-killing substances might pass from one cell to another through synapses, Greicius says.
Blueprint for the brain
To understand what goes wrong with the default network to lead to psychiatric disorders, scientists need to understand how the network is built. Assembling disparate regions of the brain into a coordinated, coherent system surely is no simple task for the developing brain.
“One might imagine that the development of self might take a bit of time to sculpt,” Raichle says.
Only a few studies have been done with children, so the picture of the nascent default network is about as clear as an ultrasound image is to someone other than an expectant parent. But new ways of analyzing neural connections are bringing the picture into better focus.
Fransson and his colleagues used fMRI to scan the brains of sleeping premature infants who had reached the equivalent of 40 weeks of gestation to see whether the default network is already in place when babies are first born. The researchers could not find evidence that the default mode is operational in newborns, although five other brain networks are already online, the team reported in 2007. Fransson says he is not surprised that newborns lack a network that draws on personal experience and dreams of what is to come.
“Infants cannot plan for their futures,” he says. “They don’t think about their pasts.”
But a recent study by Weili Lin, a neuroscientist at the University of North Carolina at Chapel Hill, and colleagues shows that infants as young as 2 weeks have rudimentary, incomplete default mode networks. The study, published in the April 21 Proceedings of the National Academy of Sciences, tracks development of the network from shortly after birth into toddlerhood. Newborns’ default networks connect six brain regions, Lin’s group found.
It doesn’t take long for the brain to develop a default mode, Lin showed. By age 1, babies link 13 brain regions in their default network, including 10 parts found in the adult network. In 2-year-olds, the default network is even bigger, comprising 19 regions, 13 consistent with the network in adults. But bigger networks can also be inefficient, Lin says, noting that adult default networks have been pruned of extraneous connections.
Lin and his colleagues are continuing to scan many of the children in the study as they age to track how the normal brain develops. Preliminary data from 4-year-olds indicate that extra connections are severed as the brain ages, he says.
A group of researchers at Washington University including Raichle, Steven Petersen, Bradley Schlaggar and Damien Fair (now at the Oregon Health & Science University) are piecing together the network’s development from age 7 into early adulthood.
Brain connections in 7-year-olds are organized differently than in adults. Children have more short-range connections among neighboring brain regions and fewer long-range connections, particularly among the parts of the default network in the back and front, the team reported last year in the Proceedings of the National Academy of Sciences. As children age, the connections are rewired. Adolescents have a network structure somewhere between that of elementary-age children and adults.
“It’s like different cliques of friends in childhood break up and create different cliques in adulthood,” Petersen says.
Given the lack of long-range connections in children’s brains, researchers were surprised to discover that kids’ default networks aren’t clunky. The team mapped how the brain makes connections in the network, a neuroscience version of the game to link actor Kevin Bacon to other actors in Hollywood through people with film appearances in common. Fewer steps means more efficient connections. While children’s connections are structured differently, they have enough shortcuts to make information transfer in the network just as efficient as in adults, the scientists reported online May 1 in PLoS Computational Biology.
Once people reach adulthood, activity in the network is fairly consistent from person to person, with some slight differences between the sexes and in older versus younger people, Williamson and his colleagues wrote in a 2008 paper in NeuroReport.
This consistency in the network from person to person is remarkable, especially considering what its function is supposed to be. Everyone’s brain is thinking different thoughts while in the default mode, Fair says, and yet all healthy brains in default mode look essentially alike.
Such fundamental issues are among the puzzles of the default network remaining to be solved.
“Nobody has really figured out what it is and what it does,” Williamson says. “But somebody will.”
Wandering and wondering
The brain’s default mode network — a series of connected areas that work hardest when most of the brain is at rest —is active during daydreaming and mind-wandering. The network may also be involved in imagining how certain situations play out and in giving people their sense of self and where they fit in the world. Many scientists believe the default network has two major hubs, one in the posterior cingulate cortex with the precuneus and one in the medial prefrontal cortex. The two hubs are highlighted in the image above, which shows a human brain viewed from the top and overlaid with a computer-generated map showing the most robust of the network’s structural connections. Also visible in the map are the left and right inferior parietal lobes, which are among a number of other brain regions involved in the default network.
Network in sync
At top, fMRI images show areas of the brain that coordinate activity when people are thinking about nothing in particular. The left image shows the outside of a left-facing brain. The right image shows the inner surface of one hemisphere of a right-facing brain. Activity in the two major hubs of the default network (indicated by yellow and orange arrows) rises and falls in time with each other, as seen on a plot of those fluctuations below.
Alzheimer’s overlaps default network
Alzheimer’s disease appears to particularly affect brain areas involved in the default network. At left, two views of the brain show areas activated (orange) when a healthy person recalls personal memories. Amyloid plaques characteristic of Alzheimer’s accumulate (red) and the brain atrophies (blue) in some of the same areas, as shown in scans of people with dementia (middle and right).
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Sunday, July 05, 2009
Promoting Rational Decisions
Cool video from Channel N featuring Daniel Kahneman on irrationality and how to promote rational decisions when “coherence is unachievable.” This was originally posted at FORA.tv.
Nobelist Daniel Kahneman on Behavioral Economics
The Georgetown 2009 graduation ceremony included this short lecture by psychologist and Nobel laureate Daniel Kahneman on irrationality and how to promote rational decisions when “coherence is unachievable.” The FORA.tv enhanced player presentation includes an indexed transcript, more info and a bio. Here’s another, longer, 2003 lecture on decision analysis and another on “Deal or No Deal” decisions given at Princeton University in 2008.
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Authors@Google: Marco Iacoboni
Marco Iacoboni is one of the better known neuroscientists - he helped popularize the discovery of mirror neurons a few years back (the neurons were originally discovered by Iaccomo Rizzolati). This is an old lecture (June, 2008) from the Google talks series, but it's still interesting.
Marco Iacoboni, a leading neuroscientist whose work has been covered in The New York Times, the Los Angeles Times, and The Wall Street Journal, explains the groundbreaking research into mirror neurons, the "smart cells" in our brain that allow us to understand others. From imitation to morality, from learning to addiction, from political affiliations to consumer choices, mirror neurons seem to have properties that are relevant to all these aspects of social cognition.
Marco Iacoboni is a neurologist and neuroscientist at the David Geffen School of Medicine at UCLA. He has appeared on Good Morning America, the Early Show, and Morning Edition, among other TV and radio programs.
This event took place on June 6, 2008, as a part of the Authors@Google series.
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Saturday, July 04, 2009
New Poem - Abstractions
Abstractions, July 4th
I can see through words,
through the clouds of thought
obscuring the circle's dripping edge
I can see beyond the limits
of logic to where the river
is everywhere, both source
and destination, both swollen monsoon
and thirsty drought,
all this and more . . .
I can see the stones as though
from tomorrow, as though
the rains have finally fallen
and the night is quenched
_____
in this place the hungry beetles caress
dark moments, frantic vibrations
signaling a life unseen
_____
a false god, the brain, more powerful
than any real god that might exist
we fail to glimpse the body of reason,
the flesh of mind, the sinew
and synapse creating thought
from frivolous sensation
so what? I ask myself,
what matter is that to those
who go to sleep hungry or alone
in the hot wet night
_____
philosophy is a luxury
of the comfortable . . .
and poets
_____
so the night collapses on itself
and we call it dawn, still hot,
the air wet with smoke
of fireworks and foolishness
this isn't why I am here,
to blow things up in celebration
of an idea, to look backward
the future stands sentinel
on tomorrow, where the stones
are wet with rain,
the dawn is cool and alive,
and the hungry are sated
with all the earth can offer
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July 4th Observation
Independence Day is passe. It was well and good to look back and celebrate the founding of the nation for a while. But there comes a time when that is no longer useful. That time has come and gone. The time of independent nations has come and gone, despite the efforts of some people to deny the global nature of human life in the 21st century.
We need an Interdependence Day, a day when race, religion, and nationality no longer divide people from each other, when we embrace the reality that we all need each other to thrive on this small planet spinning through space.
We need to recognize that isolationism is no longer a productive viewpoint. Ethnocentrism is no longer a healthy worldview. We need to take to heart the metaphor that suggests the sneeze of a butterfly in the Caribbean can impact global weather. Our reality as a species means we each are intertwined with all beings on this planet - when one person hurts another, we all suffer that pain.
But we can only hold this truth if we live with an open heart, the tender heart of the warrior that Chogyam Trungpa speaks of in Shambhala: The Sacred Path of the Warrior. We must cultivate compassion as a higher truth than separateness. We must hold the well-being and freedom from suffering of all beings as our goal.
This will never happen as long as we are bound by race, religion, or nationality. These things limit our identity. We are one people, on one planet, with a shared destiny.
We need an Interdependence Day in which we look forward to and work toward a time when compassion is the bond that unites all people as one species, comforted in our suffering, and together in our hope for a better planet.
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Lee Smolin Argues Against the Timeless Multiverse
Interesting rebuttal to the current mainstream view in physics. Smolen argues in favor of a cosmology that allows testable hypotheses based on natural selection of universes rather than the infinitely untestable hypotheses of random universes in string theory.
The unique universe
Many cosmological theories not only see our universe as one of many but also claim that time does not exist. Lee Smolin argues against the timeless multiverse
Three decades ago, talk of other universes was not seen by most physicists to be part of science. Most research in theoretical physics and cosmology concerned observable features in our universe and most papers and seminars referred to experimental results. However, since then there has been a gradual shift, during which it first became acceptable to work on theories that described not only our universe, but other possible universes, universes with less or more dimensions, or universes with different kinds of particles and forces. In the last few years, we have moved further away from theories of our one universe, as these other worlds went from being logically possible to hypothetically actual. It is now common to hear about the multiverse — a quantum cosmology that takes for granted that the visible universe that we see around us is just one of a vast or infinite number of universes.
The multiverse assumption often comes hand in hand with a metaphysical assumption regarding the nature of time. It has been argued by many experts in quantum cosmology that time is not a fundamental concept, but an approximate and emergent one. If this is correct, then we experience time in a timeless universe for reasons similar to why we, who live in a quantum universe, experience one that obeys classical physics: we are composed of very large numbers of fundamental particles and emergent statistical regularities determine much of what we experience.
Furthermore, the combination of the multiverse assumption and the timeless assumption effectively gives us a static meta-universe. Even if our own universe evolves in time, at a deeper level it is part of a timeless, eternal, ensemble of universes.
There are good reasons for these conclusions, and like many others in the field of quantum cosmology I have explored them. However, in the last few years I have come to believe that these conclusions are profoundly mistaken. In collaboration with the Brazilian philosopher Roberto Mangabeira Unger, we have been trying to understand the source of the problems and develop an alternative notion of time and law on the cosmological scale. Our reasons for doing so are based partly on concerns about whether these theories are testable by doable observations, partly on the current results of attempts to realize the timeless approach and partly on philosophical considerations.
The problem with the timeless multiverse
In a timeless world in which our universe is just one of many equally real universes, the laws of physics must be very different from those that most physicists can ever have conceived. This is because the laws of physics are no longer determinable by what we observe in our own universe, for they must apply to all of the vast ensemble of universes. A fundamental law then no longer proscribes what happens in our universe; instead it gives probability distributions for properties of the ensemble of universes.
To understand why, it is helpful to distinguish between the notion of a fundamental law and an effective law. A fundamental law is posited to hold “meta-universally” from first principles and must be unique. String theory, for instance, is an attempt at discovering such fundamental laws of nature. Effective laws, at the other extreme, govern experiments at scales that we observe directly within one universe, down to the small scales probed by the Large Hadron Collider and up to the scales probed by observations of the cosmic microwave background. We can only observe the effective laws, but we hope that it should be possible to derive them from fundamental laws — otherwise the latter has no connection with what we observe. The question is whether that indirect connection provides enough ground for experimentally testing the fundamental laws so that they are relevant for our scientific understanding of the world.
Unfortunately, it appears that if string theory, or a similar theory, is true, then the fundamental theory does not in fact predict what the effective laws of nature are. Instead, it gives rise to a vast landscape of possible effective laws — a concept I introduced in my book Life of the Cosmos (the word landscape was meant to be evocative of fitness landscapes in biology). We then must have hypotheses for how the single effective laws that describe our universe are chosen from the vast list of possibilities allowed by the fundamental theory. This is one of the major motivations for speculation about multiverses.
Several ideas have been suggested for how to select the effective laws that apply to our universe from the larger set of possibilities. One possibility, which has been much studied, is that the ensemble of universes is populated by laws by an effectively random process. An example is eternal inflation. In this scenario the process that produces the ensemble occurs at energy scales so high that they swamp any processes we have experimental access to. The result is that a universe like ours, populated by structures that depend on physics at much lower energy scales, is very atypical in the ensemble of universes. One then has to depend on the anthropic principle to pick out the very few universes hospitable to life, which are very rare in the actual ensemble. Not surprisingly, given that the characteristics of the ensemble can be postulated at will and are not subject to experimental tests, the result is that we cannot make precise and unambiguous predictions about anything observable in our own universe.
An alternative approach, which does lead to at least a few falsifiable predictions, is cosmological natural selection, which I introduced in 1992. This is based on a cosmological scenario that is constructed to be analogous to population biology. Universes are born from “bounces” deep inside black holes, which replace their singularities, where time had been hypothesized to end, with new expanding universes. This leads to a prediction that a typical universe is one where the parameters are tuned to maximize the production of black holes. There is in fact evidence that this is true of the laws that govern our universe. Most importantly, in this theory our universe is supposed to be typical of the ensemble, which leads to several genuinely testable predictions, all of which have held up since they were first published, such as the prediction that the upper mass limit of stable neutron stars is about 1.6 solar masses.
The contrast between these two kinds of multiverse theories leads to a question: why is the theory based on natural selection predictive — but not the one based on random production of universes? This helps us understand why the reality of time is necessary to explain how the laws of physics are chosen.
It is apparent that a scenario in which a population of universes evolves, rather than just being a random timeless distribution, requires a notion of time that is real at a level above individual universes. But to understand why the timeless picture fails, we have to go deeper to the foundations of quantum theory. For example, without time, and without the assumption that what exists is the single universe that we observe, it is hard to make sense of statements about probability relevant to what we observe in our universe. Since quantum mechanics is a probabilistic theory, we then run into trouble by trying to extend it to a realm where probability appears to make no sense. A number of authors have attempted to address this question, by proposing ad hoc measures for deducing predictions from ensembles of multiverses. At least up to the present time, none of these appears to be justified by anything other than the need to reproduce what we observe.
A related issue is the recovery of classical space and time, which general relativity describes, as part of an effective theory. These must be emergent aspects of a fundamental quantum theory, much like the classical notions of a particle being at a definite place and travelling on definite trajectories is emergent from quantum mechanics. This is non-trivial because the notions of quantum space—time, which arise in quantum theories of gravity, are very different.
So far, approaches to quantum gravity that assume that both space and time are emergent fail to reproduce the space—time that we know. On the other hand, two approaches that assume that time is fundamental and non-emergent succeed, at least to some extent, in describing how space—time may emerge. The most developed of these is causal dynamical triangulations, which has impressive results indicating the emergence of classical space—time. A more recent attempt, quantum graphity, also has preliminary indications for the emergence of space given the existence of time. Furthermore, fundamental time is also needed to make sense of probability and describe the evolution of effective laws, which ties to the earlier issue.
These results were the first evidence that led me to consider the idea that there might have to be a fundamental global notion of time in any fully consistent approach to quantum gravity that can recover general relativity in the approximation in which the universe is large. This hypothesis is strengthened by recent results in unimodular gravity, which several authors have argued solves the long-standing problem of the cosmological constant — something that is necessary for a large classical space—time to emerge. What is remarkable, as pointed out by the physicists Rafael Sorkin of the Perimeter Institute for Theoretical Physics, William Unruh of the University of British Columbia, Vancouver, and others, is that this approach describes evolution in a global time related to the space—time volume of the past.
What is a cosmological law?
To understand the difference between the two paradigms of emergent time versus fundamental time we need to appreciate how much of our usual notion of physical law has evolved historically from our experience of laboratory observations. In the laboratory we do not, by definition, study the whole universe. We study a small subsystem of the universe that, to some reasonable approximation, can be regarded as isolated (apart from the measuring instruments that we use to observe it). When we do this, we explore the possibility that we can prepare that closed system over and over again, at different times and in different places, with the same elements and different configurations. We abstract physical laws from what is common in a large set of experiments, and study what becomes different when the initial conditions are different. This allows us to make a clean distinction between laws and initial conditions. The laws are held to be invariant, at least over scales of time and space larger than the scales pertaining to our experiments.
This situation is almost the same for most astronomical observations. We cannot prepare stars and galaxies in any state that we want, but we can observe vast numbers of them and we can treat them as approximately isolated. Hence, in astronomy we also have a justification for distinguishing between laws and initial conditions.
The separation of scientific explanation into law and initial conditions leads to one of the most universal and powerful notions in physics — the notion of configuration space. This is the space of all possible configurations, or states, of the system. In classical and quantum physics we assume that this space exists a priori and outside of time, and that it can be studied independently of the laws of motion. These laws then specify the rules for how the point that describes the initial conditions in configuration space evolves in time. We call this the Newtonian schema for explanation.
The Newtonian schema is the basis for the claim that time is not fundamental in cosmology. From this point of view, time is seen merely as a parameter on a trajectory in configuration space, and not as an intrinsic part of the physical law. The present moment, the time we experience, has no place in this description. The philosopher who does not believe in the flow of time points to the trajectory in the configuration space and says that the only thing that is real is that the whole history of the universe exists timelessly — what in general relativity is called the “block universe” picture. Many physicists and philosophers have fallen for the temptation of believing in the “block universe” picture. To them, our experience of the flow of time is just an illusion.
This argument is faulty for two reasons. First, it does not prove that time is not fundamental. When we observe motion, we record a series of measurements of a system’s position. These can be graphed on the configuration space, resulting in a curve that represents the record of the motion. This graph is timeless, because it is a representation of a record of a past motion, which is, of course, no longer changing. The correspondence is between a mathematical object, which is static, and a series of records of observations, which is also static. The fact that we can make this correspondence between a mathematical object and a record of past motion does not imply that the actual motion that the observations sampled is timeless. Nor does it imply that behind the real evolution in time of the real world there exists a complete correspondence to a timeless mathematical object. To posit this further relation is a pure metaphysical fantasy, which is not implied by anything in the science (see "The fourth principle: mathematics and Platonism" below).
New principles
The second failure of the argument for time not being fundamental is that it is far from clear that the Newtonian schema applies on the scale of the universe as a whole. Almost all work in classical and quantum cosmology assumes that it does. But given the difficulties that these subjects encounter, I think it more likely that the answer is no.
One reason for suspecting that the Newtonian schema does not apply to cosmology is that the experimental context that gives meaning to the separation of causes into laws and initial conditions is completely missing. There is no possibility of preparing the universe in different initial configurations, and there is no way to determine by observation the full initial conditions. Any observer, within the universe, can only see a fraction of any initial-value surface. Thus, the notion of initial conditions is simply not realizable in cosmology. If there is just one universe, there is no reason for a separation into laws and initial conditions, as we want a law to explain just the one history of the one universe.
The same is true for the configuration space of the cosmos. The universe happens once, so what is the meaning of all the states that exist in state space but are never realized in the history of the universe? The notion of the “quantum state of the universe” is a fiction, divorced from anything that could be prepared or measured in practice. These considerations suggest that the notions of configuration space and state space correspond to measurements and preparations that can be operationally realized only in the case of a small subsystem of the universe. These concepts — or at least their operational basis — fail us when we try to extend them to the whole universe.
The issue of time also looks different from this perspective. Time in the Newtonian schema is a parameter used to label points on a trajectory describing the system evolving in configuration space. When the system is small and isolated, this time parameter refers to the reading of a clock on the wall of the observer’s laboratory, which is not a property of the system. When we try to apply this notion to the universe as a whole, the time parameter must disappear. Some have attempted to argue that this means that time itself does not exist at a cosmological scale, but that is the wrong conclusion. What disappears is not time, but the clock outside of the system — which would be an absurd object since the system is the whole universe.
Indeed, it may be that sticking to the Newtonian schema, when it has no operational significance, leads us to take the multiverse scenario seriously. If our scientific methodology only makes sense when applied to subsystems of a vaster universe, then it is tempting to react to the problems that arise when we try to extend it uncritically to that whole universe by positing that our universe is in fact a subsystem of an even vaster multiverse. We get to do physics as we have been trained to, but this is a trap because to do this we must employ structures that have no operational significance. Better, in our view, to regard the Newtonian schema as inapplicable to cosmology, and to look for another notion of law that can make sense when applied to our entire, but single, universe.
But once we state that the distinction between laws and initial conditions has no counterpart in the cosmological context, this renders moot several puzzles that the extension of the Newtonian paradigm to cosmology has brought about. What is the initial quantum state of the universe? How do we interpret it? How do we define probabilities in quantum cosmology? How do we do physics when time has disappeared?
The physical law in a single, time-bound universe
By discarding the Newtonian schema for cosmology and dispensing with the notion of the multiverse, we also no longer have any reason to suspect that time is an illusion. This led Unger and me to consider the implications of a natural philosophy based on a different set of principles.
1. There is only one universe. There are no others, nor is there anything isomorphic to it.
This logically implies that there are no other universes, nor copies of our universe, whether within or without. The first is impossible as no subsystem can model precisely the larger system it is a part of, while the second is impossible because the one universe is by definition all there is. This principle also rules out the notion of a mathematical object isomorphic in every respect to the history of the entire universe, a notion that is more metaphysical than scientific.2. All that is real is real in a moment, which is a succession of moments. Anything that is true is true of the present moment.
This says that not only is time real, but also that everything else that is real is situated in time. Nothing exists timelessly.3. Everything that is real in a moment is a process of change leading to the next or future moments. Anything that is true is then a feature of a process in this process causing or implying future moments.
The third principle incorporates the notion that time is an aspect of causal relations. A reason for asserting it is that anything that just existed in a moment, without causing or implying an aspect of the state at a future moment, would be gone in the next moment. Things that persist must be thought of as processes leading to newly changed processes. An atom in a moment is a process leading to a different or a changed atom in the next moment.This alternative metaphysical framework has implications for the nature of physical law. Since nothing is true or real outside of time, there is no possibility of speaking of eternal laws. Laws are regularities that we discover hold for very long stretches of time, but there is no reason for laws to be true timelessly — indeed, there is no way to make sense of that notion. This opens the door to the possibility that laws evolve in time, which is an idea that has been on the table ever since the great American logician Charles Sanders Peirce wrote in 1891 that “To suppose universal laws of nature capable of being apprehended by the mind and yet having no reason for their special forms, but standing inexplicable and irrational, is hardly a justifiable position. Uniformities are precisely the sort of facts that need to be accounted for. Law is par excellence the thing that wants a reason. Now the only possible way of accounting for the laws of nature, and for uniformity in general, is to suppose them results of evolution.”
From this point of view, the notion of transcending our time-bound experiences in order to discover truths that hold timelessly is an unrealizable fantasy. When science succeeds, we do nothing of the sort; what we physicists really do is discover laws that hold in the universe we experience within time. This, I would claim, should be enough; anything beyond that is more a religious urge for transcendence than science.
So, what is physics without a clean separation into laws and initial conditions, and hence, without the notion that there is a space of configurations that exists timelessly? We do not know the full answer to this, but we have a few observations.
First, by discarding the Newtonian schema for cosmology we have much less reason to consider our universe one of many other actual universes. Indeed, we may also be able to dispense with the notion of a vast number of other possible universes, that somehow are never realized. We can imagine instead a notion of law that applies only to the single universe that really exists. We also no longer have any reason to suspect that time is an illusion because, as outlined above, the main arguments from physics for time being emergent and not fundamental come from the misapplication of the Newtonian schema to the universe as a whole.
As we attempt to realize those principles, we seek a notion of law that cannot be applied to an imagined universe within a multiverse, and which cannot be imagined to hang around timelessly waiting for a universe to begin that it can then govern. Given that the universe only happens once, we must try to imagine a new kind of law that applies only that one time. Such a law need not — and should not — have any sense in which it exists outside of time. Nor could it be conceived of as apart from the universe it describes. It might indeed be a law that evolves in time; that is, a law where the distinction between a one-time narration of the history of the one universe and the statement of principles governing that history weakens.
If the timeless multiverse paradigm now ascendant is correct, then we are approaching the end of a process that will eliminate the reality of time and replace it with a shadowy kind of “existence” within an eternal frozen world consisting of vast numbers of possibilities. If, on the other hand, the principles that Unger and I propose are closer to the truth, then we are at the beginning of a new adventure in science where we have to reconceive the notion of law to apply to a single universe that happens just once. In either case we will end up conceiving our universe in very different and less familiar terms than before.
But did we really imagine that completing the revolution started by Einstein would be possible without having to discard some of our comfortable beliefs in favour of disturbing and almost inconceivable new ideas? At this level we do science not for ourselves, but for the future generations that will live comfortably in conceptual worlds that we can at best only point roughly towards. Press)
At a Glance: Against the timeless multiverse
• Many cosmologists today believe that we live in a timeless multiverse — a universe where ours is just one of an ensemble of universes, and where time does not exist • The timeless multiverse, however, presents a lot of problems. Our laws of physics are no longer determinable from experiment and it is unclear what the connection is between fundamental and effective laws • Furthermore, theories that do not posit time to be a fundamental property fail to reproduce the space—time that we are familiar with • Many of these puzzles can be avoided if we adopt a different set of principles that postulates that there is only one universe and that time is a fundamental property of nature. This scenario also opens the way to the possibility that the laws of physics evolve in time.
The fourth principle: mathematics and Platonism
Believers in eternal truth often point to mathematics as a model of a realm with timeless truths. What is called the Platonic view of mathematics holds that mathematical objects (the things that the theorems of mathematics are about, such as numbers, spheres, planes, curves and so on) exist in a separate timeless realm of reality. Mathematicians explore this realm with their minds and discover truths that exist outside of time, in the same way that we discover the laws of physics by experiment. But mathematics is not only self-consistent, it also plays a central role in formulating laws of fundamental physics, which the physics Nobel laureate Eugene Wigner once referred to as the “unreasonable success of mathematics in physics”.
One way to explain this success within the dominant metaphysical paradigm of the timeless multiverse is to suppose that physical reality is mathematical, i.e. we are creatures within the timeless Platonic realm. The cosmologist Max Tegmark calls this the mathematical universe hypothesis. A slightly less provocative approach is to posit that since the laws of physics can be represented mathematically, not only is their essential truth outside of time, but there is in the Platonic realm a mathematical object, a solution to the equations of the final theory, that is “isomorphic” in every respect to the history of the universe. That is, any truth about the universe can be mapped into a theorem about the corresponding mathematical object.
If nothing exists or is true outside of time, then this is all wrong. However, if mathematics is not the description of a different timeless realm of reality, what is it? What are the theorems of mathematics about if numbers, formulas and curves do not exist outside of our world? This leads Unger and me to a new view on mathematics that can be summarized in a fourth principle.
4. Mathematics is derived from experience as a generalization of observed regularities when time and particularity are removed.
Consider a game, for example chess. It was invented at a particular time, before which there is no reason to speak of any truths of chess. But once the game was invented, a long list of facts became demonstrable. These are provable from the rules, and can rightly be called the theorems of chess. These facts are objective, in that any two minds that reason logically from the same rules will reach the same conclusions about whether a conjectured theorem is true or not.Now a Platonist would say that chess always existed timelessly in an infinite space of mathematically describable games. We do not achieve anything by believing that, except an emotion of doing something elevated. Moreover, it is clear that a lot is lost; for example, we have to explain how it is that we finite beings embedded in time can gain knowledge about this timeless realm. We find it much simpler to think that at the moment the game was invented a large set of facts become objectively demonstrable, as a consequence of the invention of the game. We have no need to think of them as eternally existing truths, which are suddenly discoverable, instead we can say they are objective facts that are evoked into existence by the invention of the game of chess. Our view is that the bulk of mathematics can be treated the same way, even if the subjects of mathematics such as numbers and geometry are inspired by our most fundamental observations of nature. Mathematics is no less objective, useful or true for being evoked by and dependent on discoveries of living minds in the process of exploring the single, time-bound universe.
More about: Against the timeless multiverse
R Bousso, B Freivogel and I-S Yang 2008 Boltzmann babies in the proper time measure Phys. Rev. D 77 103514
R Loll 2008 The emergence of spacetime or quantum gravity on your desktop Class. Quantum Grav. 25 114006
F Markopoulou 2008 Space does not exist, so time can
www.fqxi.org/community/essay/winners/2008.1
L Smolin 2000 The present moment in quantum cosmology: challenges to the arguments for the elimination of time
Time and the Instant (ed) R Durie (Manchester, Clinamen Press)
L Smolin 2006 The status of cosmological natural selection arXiv:hep-th/0612185
R M Unger 2007 The Self Awakened: Pragmatism Unbound (Harvard University
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Dalai Lama on Community
A nice brief quote from the Dalai Lama on world community.
Our world is becoming one community. We are being drawn together by the grave problems of overpopulation, dwindling natural resources, and an environmental crisis that threatens the very foundation of our existence on this planet. Human rights, environmental protection and greater social and economic equality are all interrelated. I believe that to meet the challenges of our times, human beings will have to develop a greater sense of universal responsibility. Each of us must learn to work not just for oneself, one's own family or nation, but for the benefit of all humankind. Universal responsibility is the key to human survival. It is the best foundation for world peace.
--from The Pocket Dalai Lama by the Dalai Lama, compiled and edited by Mary Craig
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