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Thomas Ray: "What makes the complex plane algebraically closed, is that it gives up an..." in Classical Spheres,...

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RECENT ARTICLES
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Reality's NeverEnding Story
A quantum version of Darwinian natural selection could enable the universe to write itself into being.

The Quantum Dictionary
Mark Van Raamsdonk is re-writing how we define the shape of our universe. Can such translations help to unite quantum theory and gravity?

Q&A with Paul Davies: What is Time?
Where does time come from? Why does it seem to flow?

Quantum Computers Get Real
Fighting decoherence to scale up quantum technologies.

Q&A with David Rideout: Testing Reality in Space
Satellite experiments could soon investigate the boundaries of quantum physics and relativity.


FQXi BLOGS
April 20, 2014

New Blog Entries
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How Should Humanity Steer the Future?
By BRENDAN FOSTER • Apr. 19, 2014 @ 04:51 GMT

Greetings all -- Just a quick announcement to say our current essay contest -- How Should Humanity Steer the Future? -- is closed for entries as of now. We are currently reviewing all the great entries that arrived in the past few days, so expect to see new essays continuously posted over the next week. Enjoy!
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FQXb (bio)
By WILLIAM OREM • Mar. 23, 2014 @ 21:39 GMT



Everyone is talking this week about the dramatic confirmation of inflationary theory: those first-instant gravitational waves whose details may even point--being, if you will, quantum phenomena that went suddenly ultra-macroscopic--toward the correct way to unify QM and GR.

I myself have been musing on rather astonishing work in another field. Will you pardon the intrusion if we talk a little bit about biology?

Recently the big news there was released: an unprepossessing experiment involving a weak acid bath showed it's possible to revert mature, differentiated cells to a stem cell state, allowing for the prospect of wholesale repurposing. The surprise wasn't that reversion (or conversion from one mature type into another) can be done--genetics work in that direction took home a Nobel in 2012--but that it can be done so simply. Since FQXers are a physics crowd, you might say it's a bit like someone offhandedly noticing you can trigger a controlled fusion reaction by rewiring a microwave oven.

This is the angle most science journalists gave the discovery last month: "Outsider runs outrageous experiment, stumbles upon success." Charles Vacanti's brilliance, we were told--"outsider" because he's an anesthesiologist, without even a Ph.D.--came in trying something that anyone could have done, but nobody though to, because it was just too unlikely. There can be a virtue to not being too educated in a certain field; to get all Zen about it, "In the beginner’s mind there are many possibilities; in the adult's mind, there are few."



Alas--you knew this part was coming--it is now looking like the champagne may have been premature. There are certain "improprieties in the data," as it has been politely phrased in the weeks since. (Or, as a friend of mine--himself a Harvard neuroscientist--more trenchantly put it: "A weak acid bath? Give me a break.") One of the photographs in the article has already been confirmed to be a goof. No one is averring foul play, but whether we have a home-run or a whiff is in serious question.

Either way, though, I'm left musing.

Were I to win the Lottery tomorrow, I would immediately do two things: fund FQXi indefinitely and expand it into other fields. Imagine an FQXpb (psychobiology) or an FQXg (genetics). After all, it is not only cosmology and high energy physics that carry foundational questions. Who was it that floated the idea--wacky, but rather wonderful to contemplate--that if "junk DNA" really has no purpose, at some point we might want to mine it for communication, perhaps put there by the species that fabricated us? (In his novel Contact, Carl Sagan came up with lovely notion that pi, when you advance to the point of being able to decipher its pattern, turns out to be an instruction manual on how to operate reality from the beings who engineered this region of spacetime.)

So, in the spirit of FQX bio, let's just assume for the moment that Vacanti et. al. paper is correct. What follows? Therapies for spinal cord injury and damaged heart tissue, by all means; bring them on. But what really would be interesting would be the fact of simple cellular reversibility. This phenomenon would be telling us something completely surprising about what cells are, at a deep level--and what, by extension, we ourselves are.

As a finding, it's counterintuitive. Why should cells, already long since differentiated, be capable at all of reverting to a stem state, as if awaiting reassignment? (As Rabi said of the muon, who ordered that?)

Is this a natural propensity of all cellular life? Is mutability far more common than has been understood? Does cell reversion happen all the time in the body, and we just never noticed it? (Don't scoff; we should remember it was the 16th century before medical science understood the circulation of the blood.) Could this be a key to understanding what cancers are, at a deep level?

From Carolyn Y. Johnson's Boston Globe article of Feb. 17:

"Even normal cells appear to contain a capacity for regeneration far more powerful than anyone knew. This new idea is opening up profound, almost philosophical questions about why cells would have this capacity. [ . . . ]

'It's slowly changed how we think about life, and I know that sounds grandiose, but it's not grandiose at all,' said Dr. Richard T. Lee, a stem cell scientist at Brigham and Women's Hospital."

Life coming to know itself; not too grandiose at all, I should think.


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BICEP2: Primordial Gravitational Waves & Evidence for Inflation
By ZEEYA MERALI • Mar. 17, 2014 @ 13:08 GMT

Updated: Congratulations to FQXi's Alan Guth and Andrei Linde following the announcement of the first direct detection of B modes -- evidence of their inflation theory. Well done to those working on BICEP2, and all others who have contributed to the development of inflation theory over the years. Here's a lovely video, from Stanford University, showing Linde's reaction to the news:



Rumours have been flying since last week about a major discovery that will have implications for our understanding of the early universe. Later today—as I'm certain you will already have heard—there will be an official announcement from the BICEP2 experiment. The experiment involves a ground-based telescope at the South Pole, specifically designed to look for the "B-mode" signature of inflation (a predicted period of rapid acceleration of the universe in its infancy) in the CMB.

This is a thread to discuss what looks most likely to be the announcement of some level of discovery of such B modes, a twisted signature in the polarisation of CMB light that could only have been made by primordial gravitational waves—ripples in the fabric of space-time, set off by the rapid acceleration of space-time during inflation. Gravitational waves have been predicted to exist by general relativity, but primordial gravitational waves are considered to be evidence for inflation theory, in particular, because only period of massive expansion in the early universe could leave us with a detectable imprint of them today.

Details on where to watch the announcement and read the papers (once available) are here:

Dear friends and colleagues,

We invite you to join us tomorrow (Monday, 17 March) for a special webcast presenting the first results from the BICEP2 CMB telescope. The webcast will begin with a presentation for scientists 10:45-11:30 EDT, followed by a news conference 12:00-1:00 EDT.

You can join the webcast from the link at www.cfa.harvard.edu/news/news_conferences.html

Papers and data products will be available at 10:45 EDT from http://bicepkeck.org.



thank you, John Kovac, Clem Pryke, Jamie Bock, Chao-Lin Kuo on behalf of The BICEP2 Collaboration


Stuart Clark has written an overview of the impact of such an announcement, for The Guardian, including comments from FQXi's Hiranya Peiris.

Sean Carroll has rounded up some slightly more detailed blog posts on the subject, in addition to giving his own excellent primer on the topic.

For a slightly more technical description of the different types of polarisation in the CMB, what B Modes are, and how they would be left behind by the passage of gravitational waves, you can see a great slideshow by Daniel Baumann.

Update: And here's the paper.
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Time and the Nature of Reality
By ZEEYA MERALI • Mar. 8, 2014 @ 18:28 GMT

Anthony Aguirre
We recently ran an article (courtesy of Nautilus Magazine) in which physicist Paul Davies ran through some open questions about the nature of time.

I want to alert you to another discussion currently taking place on the Big Questions Online site based on a terrific essay by none other than FQXi's own supremo Anthony Aguirre asking, "What Does Our Understanding of Time Suggest About the Nature of Reality?"

Anthony close his essay with a terrific set of questions, which I am just cutting and pasting here:

1. If the speed of light were much slower, so we could really experience the subjectivity of simultaneity implied by Relativity, how to you think it would change our experience of time, space, and the world?

2. If you truly believed that the past, future, and present all exist in just the same way, as in the Unitary Block view, would it change your attitude toward life -- or death, or decisions?

3. If there are aspects of the world that are unpredictable in principle, is there still a sense in which we can say that they are determined?  Or do those two ideas go hand-in-hand?

4. I've suggested that part of the controversy over how to think about quantum mechanics is a controversy over whether the classical, macroscopic world emerges from the quantum world, or whether the quantum world is a particular, stripped-down limit of an essentially classical world.  How do you see it? What theoretical or experimental findings might lead you to accept one view as more viable than the other?

Please do visit BQO to take part in this discussion and more.
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Video: Seth Lloyd, "What Happens When You Fall Into a Black Hole?"
By ZEEYA MERALI • Mar. 4, 2014 @ 21:19 GMT

Some of you may have noticed that I enjoy writing about the question of what happens when you fall into a black hole. At the recent FQXi meeting in Vieques, Puerto Rico, "quantum mechanic" Seth Lloyd talked through this problem and discussed a way to potentially escape a black hole, first proposed by Horowitz and Maldacena, which uses quantum teleportation to smuggle information out--but also violates some quantum laws, in return.

Here is Seth, describing it in his inimitable style. He also explaining why, if you are unlucky enough to cross an event horizon, you shouldn't try and fire up the engines of your rocket and accelerate away from the singularity…because you'll only die faster.



For more about the debate over the fate of an unfortunate astronaut heading into a black hole, here's Anil Ananthaswamy's story about Steve Giddings' research, "Black Holes: Paradox Regained." There's also a story I wrote for Nature last year on the firewall debate, based on the work of Joe Polchinski, Don Marolf, Giddings and others, which pits general relativity against quantum physics--and tries to answer whether the space traveller would be spaghettified, as traditionally thought, or burnt to a crisp at the event horizon. And a follow-up discussing Stephen Hawking's take on the whole issue.
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Recent Blog Entries

Is the universe infinite or just really really...
By IAN DURHAM
As promised, this is a follow-up to one of the summary posts from the FQXi conference in Vieques. If you have read those, you may recall that Anthony Aguirre asked the intriguing question: is there any way for us to tell if the universe is infinite...
February 3rd, 2014 | 45 comments | view blog entry & comments

Might the Infinity of the Universe Have a Tangible...
By GEORGE MUSSER
“There is a difference between whether the universe is infinite or just really really really really really really big,” Anthony Aguirre said at the recent FQXi conference in Puerto Rico. I’m pretty sure I counted six reallys. With that remark,...
January 25th, 2014 | 54 comments | view blog entry & comments

Consciousness as a State of Matter--Max Tegmark's...
By ZEEYA MERALI
[picture]More audio from the FQXi meeting in Vieques, this time from cosmologist Max Tegmark. As Ian has already blogged, Max has been pondering what qualities conscious matter would have that differentiates it from non-conscious matter.

In...
January 21st, 2014 | 47 comments | view blog entry & comments

Time From a Timeless World
By GEORGE MUSSER
Theoretical physicists commonly say their biggest challenge is to unite general relativity with quantum theory. But at this month’s FQXi conference in Puerto Rico, Carlo Rovelli said they have an even bigger challenge: to unite general relativity...
January 21st, 2014 | 55 comments | view blog entry & comments

Interesting Ways to Die (and More)
By IAN DURHAM
[picture]The final full day of the conference in Vieques began with a session on quantum gravity. (Some slides and videos from the meeting are now up: here.) Seth Lloyd led off the longer talks by essentially summarizing what we know about in-falling...
January 20th, 2014 | 7 comments | view blog entry & comments

The History of Astronomy with Julian Barbour and...
By ZEEYA MERALI
This is a quick post to alert you to a new video project by FQXi members Julian Barbour and Flavio Mercati. Backed by FQXi, they are creating a series of films, in English and Italian, on the history of astronomy. Here is part one, in Italian, but...
January 17th, 2014 | 1 comment | view blog entry & comments

String theory vs Loop Quantum Gravity: Bousso and...
By ZEEYA MERALI
Depending on how familiar you are with FQXi, you may know that we like to cause a little mischief at our conferences. Knowing that we had famed string theorist Raphael Bousso and Carlo Rovelli, one of the originators of loop quantum gravity, in the...
January 14th, 2014 | -1 comments | view blog entry & comments

Fluctuations, Schmucuations
By GEORGE MUSSER
PUERTO RICO—One of my favorite talks at the recently concluded FQXi conference was Sean Carroll's takedown of the concept of quantum fluctuations in inflationary cosmology. Regardless of the fate of his overall argument—which my fellow FQXI...
January 14th, 2014 | 29 comments | view blog entry & comments

Consciousness, Free Will--and Asking Siri Out on a...
By IAN DURHAM
As I mentioned in my previous post, they keep us rather busy at this conference so I did not have the opportunity to put additional thoughts down on "paper" until just now as I sit in the Philly airport for the next few hours (it’s January and...
January 14th, 2014 | 24 comments | view blog entry & comments

FQXi'ers Debate the Deep Questions of Free Will
By GEORGE MUSSER
VIEQUES, PUERTO RICO—Some years ago, while visiting South Africa, I was astounded by the number of languages my friends spoke. It’s not just they knew Xhosa, Zulu, SeSotho, English, and Afrikaans, but that they moved freely among languages to...
January 10th, 2014 | 28 comments | view blog entry & comments

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