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Georgina Parry: "P.S. 3D "Blender" models can also be animated, or imported into other..." in Call for Research...

Georgina Parry: "Thanks for your advice Eckard. All, Certainly projective geometry has a..." in Call for Research...

dieu le: "Big Bang: “Unjustifiable From a Physical Point of View” The physics..." in Is the Past Infinite?

Chuck Stark: "As a Mathematics undergraduate with a Physics minor, this topic is near and..." in Trick or Truth? — Essay...

Anton Vrba: "Brendan, Wow what a fantastic essay topic, congratulations! After skipping..." in Trick or Truth? — Essay...

Peter Jackson: "John, It's clear that space can have 0 'condensed 'matter', but you've not..." in Alternative Models of...

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Quantum in Context
An untapped resource could provide the magic needed for quantum computation—and perhaps even open the door to time travel.

Spot the Difference to Reveal Exotic Particles
Questioning the symmetrization postulate of quantum mechanics and the notion that electrons are indistinguishable could reveal whether hypothetical new particles exist.

Life's Quantum Crystal Ball
Does the ability to predict the future—perhaps with quantum help—define the fundamental difference between living and inanimate matter?

The Quantum Truth Seeker
Watching particles fly through an interferometer might help to unveil higher-order weirdness behind quantum theory.

Quantifying Occam
Is the simplest answer always the best? Connecting Medieval monks to computational complexity, using the branch of mathematics known as category theory.

December 19, 2014

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Trick or Truth? — Essay Contest 2015
By BRENDAN FOSTER • Dec. 16, 2014 @ 02:02 GMT

Physics and mathematics -- It seems impossible to imagine the history of either one without the other. For gravity theory alone, we see so many examples of this -- from Newton creating calculus, to Einstein mining differential geometry.

But how close is this relationship? How deep does it go? Does physics simply wear mathematics like a costume, or is math in the blood of physical reality?

And so, Introducing our 2015 contest topic: Trick or Truth? - The Mysterious Link Between Physics and Mathematics.

Why does math seem so "unreasonably" effective in fundamental physics, especially compared to math's impact in other scientific disciplines? Or does it? How deeply does mathematics inform physics, and physics mathematics? What are the tensions between them -- the subtleties, ambiguities, hidden assumptions, or even contradictions and paradoxes at the intersection of formal mathematics and the physics of the real world?

In this essay contest, we ask all of you to probe the mysterious relationship between physics and mathematics. As always, we are giving away over $40,000 in prizes, including a top prize of $10,000. Please read the contest pages for instructions, full rules, and a lengthy list of sample questions to start your thinking.

For those of you familiar with our previous contests, let me mention a couple small but important changes to our rules.

First off, the make-up of our pool of finalists. Our finalist pool this year will consist of the familiar set of 30 top-rated entries (as rated by entrants and FQXi Members) plus auto-inducted Member entries. In addition, our Review Panel this year will have the power to add up to 10 more finalists of their choosing. This new rule means that ALL entries will be eligible for the top prizes. However, only the entries in the base set of 30 have the guarantee that the panel will read them.

Second, inspired by the smooth runnings of our first ever Video Contest (Show Me the Physics!), we are resetting the prizes. Our First Prize is still $10,000; Second Prizes are still $5,000, and Third Prizes are still $2,000. This year, only first and second prizes will receive Membership nominations. And, in place of the familiar Fourth Prizes, we will give our review panel a pool of money -- $12,000 -- to divide up as they see fit. Prizes could go to best "amateur" entry, most original presentation, deepest insight, or whatever the panel sees fit to do.

The contest is open to anyone, so please share this info with everyone. Good luck and good writing!
4 comments | view comments

Call for Research Proposals: The Physics of What Happens
By ZEEYA MERALI • Dec. 12, 2014 @ 13:46 GMT

It's good to take a philosophical attitude to life. Let's say you apply for an FQXi large grant. Maybe you get it, maybe you don't. Whatever happens, happens.

But what does *happen* from the point of view of physics? What constitutes an "event"? We're announcing our 2015 competition, with US$2 million to give out in grants, for projects that investigate "events". Full details can be found here.

The current request for proposals targets research on the Physics of "Events" both in physics and also in related fields including cosmology, astrophysics, philosophy of physics, complex systems, biophysics, computer science, and mathematics.

Everyday reality is largely made up of events: things that happen and don't "un-happen." These events separate the past from the future via the present, in which events are "happening." The world of fundamental physics, however, is quite different.

In general relativity, for instance, "event" simply refers to a space-time location, which may or may not coincide with something happening. The theory has no fundamental entity that corresponds to an event that "happens" or does not. In quantum mechanics, the measurement of some observable can constitute an "event," but this process is subject to differing theoretical and philosophical interpretations. The evolving wavefunction -- like the evolving matter and gravitational fields in GR -- has no "event" built in; they must be identified by reference to a laboratory or other macroscopic observer. Furthermore, it is unclear to what extent events in the macroscopic world should really be considered quantum measurements of the archetypal variety studied in the quantum foundations literature.

Thus, both of our fundamental theories of physics are by themselves event-free (or at best "event-lite"), and we face the question of how to draw a firm connection between these theories and the events that make up what happens in experienced reality. Drawing those connections -- and through the process, analyzing the notion of "event" as it appears in its many forms throughout physics -- is the aim of this request for proposals. A longer list of example questions is available here.

Initial proposals are due on February 15, 2015. If you have any questions, please contact
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Please Join Us For the 2014 FQXi Video Contest Award Ceremony
By ZEEYA MERALI • Dec. 2, 2014 @ 23:42 GMT

It's time to get out your ballgowns and tuxedos. FQXi is rolling out the red carpet and inviting you to join us as we announce the winners of our first ever video contest: "Show Me The Physics!"

As Brendan hinted in an earlier post, the judges have now made their decisions. The three top prize winners will be walking away with $10,000. We are also awarding $3000 each to the best video by a young scientist and to the creator of the audience's top pick. We're also distributing a large number of discretionary prizes for videos that impressed us, educated us, or just amused us in some way.

So join FQXi's directors Max Tegmark and Anthony Aguirre (along with some special guests) as they open the envelopes. Will there be tearful acceptance speeches? We shall see.

The event: The FQXi Video Contest Award Ceremony 2014

The time: Friday 5 December, 1:30pm ET

The place: Here

In the meantime, thank you to all entrants and to everyone who viewed, rated and commented on the videos. You can still enjoy them all here.

*Edited on 4 December 2014 to add that there's more exciting news! Max and Anthony will also be revealing more about the next grant round *and* FQXi's essay contest, launching soon.

**Edited on 8 December 2014 to add that here is the full list of winners. Congratulations to them all, and thank you to everyone who took part.
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Planck Sheds Light on Dark Matter and Closes the Gap with WMAP
By ZEEYA MERALI • Dec. 2, 2014 @ 20:19 GMT

This image isn't a close-up of part of Van Gogh's "The Starry Night," but it is a patch of sky showing the swirling the magnetic field inferred from Planck data. (Image via ESA-Planck Collaboration, prepared by Marc-Antoine Miville-Deschenes.)

Yesterday, the Planck collaboration announced more CMB results and there's been plenty of news coverage. There aren't many dramatic findings. If anything, discrepancies between Planck's earlier data and WMAP's CMB data seem to be reducing, as more Planck data comes in. From Adrian Cho, quoting Nazzareno Mandolesi, a cosmologist with Italy's National Institute for Astrophysics in Bologna, in Science:

"WMAP and Planck had disagreed by about 1% to 1.5% on their absolute temperature measurements, Mandolesi explains. A recalibration reduces the mismatch to less than 0.3%, within the statistical uncertainties, he says. Regarding the parameters of the cosmological theory, Planck researchers derived a slightly longer age and a slightly smaller current expansion rate for the universe than WMAP showed, Mandolesi says. But with more data, the numbers have shifted slightly and now agree to within the experimental uncertainties, he says."

It does help us narrow in on what dark matter may be, or rather what it's not. From Dennis Overbye in the NYT:

"Recently space experiments like NASA's Fermi Gamma-ray Space Telescope and Alpha Magnetic Spectrometer have recorded excess cosmic ray emissions that, some say, could be evidence of a certain kind of dark matter particles colliding and annihilating one another.

"After Planck, we need another answer for those experiments, the French agency concluded in a statement."


"Planck dealt a blow to another possible dark matter candidate, namely a brand of the ghostly particles known as neutrinos. Physicists have known of three types of neutrinos for some time and have wondered if there were any more, whose accumulated mass would affect the evolution of the universe. Planck's results leave little room for a fourth kind, so-called sterile neutrinos."

While we're waiting for the joint analysis by Planck and the BICEP2 team to say something about the latter's claimed evidence of B-modes supporting inflation--and while I'm subtly plugging the podcast by opening a few threads today--I'll invite you to listen to our podcast interview with astrophysicist Andrew Liddle from October to help put things into perspective.

Planck's polarization map of the CMB.
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Janus Universes and a Gravitational Arrow of Time
By ZEEYA MERALI • Dec. 2, 2014 @ 19:54 GMT

Janus, Vatican museum, photo by Loudon Dodd
We can always count on FQXi member Julian Barbour to raise the tone of the conversation, this time by referencing the Roman two-faced god Janus with his new theory that explains the origin of time's arrow, using gravity (Phys. Rev. Letts, 113, 181101).

I've just opened a thread on for discussing our latest podcast (29 November 2014), but I neglected to open one for the previous podcast, which featured an interview with Barbour and his colleague Flavio Mercati, who spoke about their new model. According to them, the big bang gave rise to two back-to-back "Janus universes," with arrows of time that run in opposite directions. Their model also runs counter to the usual conception in which the arrow of time tracks *increasing* entropy in the universe; they argue instead that as time progresses, the universe's entropy *decreases*.

Since that podcast interview was posted in October, Barbour's model has been gaining interest. The APS highlighted the work with a Viewpoint piece, in which Steven Carlip provides commentary on the paper, describing mysteries about the arrow of time that must still be addressed (such as why the arrows that arise from different physical phenomena, not just gravity, all point in the same direction).

Bob Yirka at has also written an accessible account of the team's research.

So, if you haven't already, please do go back and listen to Barbour's interview with us, from October.

What do you think? Is this enough to solve the problem of the origin of time's arrow?

In the same edition you can hear another expert on the physics of time, Paul Davies, talking about something quite different: his atavistic model for cancer, which he likens to a cell's "safe mode" that's triggered when the cell faces an environmental threat and reboots itself. For more on this topic, you can also see a news item that I wrote for Scientific American: "Did Cancer Evolve to Protect Us?"

Physical Review Letters

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Recent Blog Entries

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Dust Settling on the BICEP2 results
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The Quantum Pet Store: New Podcast Edition is Up!
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Your Invitation to FQXi's Online Essay Contest...
The judges have made their decisions…and we can now (almost) reveal the winners of this year's essay contest, which asked: "How Should Humanity Steer the Future?" We had 155 entries this year and we're awarding 16 prizes. Thank you to everyone who...
August 20th, 2014 | 215 comments | view blog entry & comments

Quantum theory escapes locality by accepting...
[picture]When a ballerina does a pirouette she must escape the friction of the ground in order to get the freedom to move. (Figure 1: Photo by Michael Garner, courtesy of English National Ballet.) She does this by restricting her contact with the...
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Looking for a low-level break from your usual high-level philosophizing about science? Check out Luc Besson's latest: a sci-fi shoot-em-up titled *Lucy* that will keep you crunching popcorn without straining too many...
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“Utopia or Dystopia”
Rick Searle of the Institute for Ethics and Emerging Technologies has a post up about this year’s essay contest. Check it out here.

The essay contest is now closed for votes, but as you know, it is still open for debate.

July 8th, 2014 | 129 comments | view blog entry & comments

Consciousness = Maths, Simulating Time Travel,...
Just a quick round-up of some more video and audio on offer.

If you've been following Max Tegmark's latest ideas on consciousness as a state of matter (which I blogged about in January), then you'll enjoy his TEDx Cambridge talk:...
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