Editor's Choice: The Rise of the Anti-Universe
By ANIL ANANTHASWAMY • Jun 20, 2009
How our youthful universe explored the string-theory multiverse in search of home, with help from its anti-universe counterpart. This early odyssey may explain why our cosmos is so well-suited for life.
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Readers' Choice: The Quantum Arrow of Time
By SOPHIE HEBDEN • Jun 6, 2009
Can Schrödinger's cat explain the origin of time and why we won't ever be able to turn back the clock and age backwards?
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The Holographic Universe
By ANIL ANANTHASWAMY • May 22, 2009
Take one universe. Turn it into a hologram. Find its quantum wavefunction. Understand the birth of our cosmos.
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Much Ado About Nothing
By BOB SWARUP • May 8, 2009
Does the vacuum regenerate itself to fill the gaps as spacetime is pulled apart? Could a growing vacuum explain dark energy?
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Measuring Up the Multiverse
By KATE BECKER • Apr 24, 2009
How (un)usual is our universe in the multiverse? Could it have been dreamt up by a disembodied, hallucinating quantum brain?
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The Many Lives of Hugh Everett III
By GRAEME STEMP-MORLOCK • Apr 10, 2009
Investigating the troubled genius behind parallel worlds.
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Out of the Darkness
By BOB SWARUP • Mar 27, 2009
Deciding the winner as dark matter, dark energy, and general relativity slug it out with rival theories.
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Editor's Choice: Quantum Upsizing
By GRAEME STEMP-MORLOCK • Mar 13, 2009
Pushing the quantum-classical limit by attempting to build the largest ever quantum object.
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Taming Infinity
By ANIL ANANTHASWAMY • Feb 27, 2009
The fight to save both general relativity and quantum mechanics—by defeating infinity.
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Readers' Choice: The Emperor's New Swindle
By JULIE REHMEYER • Feb 13, 2009
Quantum mechanics is the biggest con trick in physics—according to the collaboration striving to demystify it.
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The Curious Case of the Quantum Arrow of Time
By SOPHIE HEBDEN • Jan 30, 2009
Can Schrödinger's cat explain the origin of time?
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Through a Glass, Darkly
By ANIL ANANTHASWAMY • Jan 16, 2009
Illuminating the murky 10-D world of string theory requires some mind-bending 8-D math.
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Back to Mach
By KATE BECKER • Jan 2, 2009
Want a theory of quantum gravity? Then look to the man who inspired Einstein.
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The End of the Quantum Road?
By BOB SWARUP • Dec 19, 2008
Have we already found the ultimate theory of nature, without realizing it?
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The Universe's Odyssey?
By ANIL ANANTHASWAMY • Dec 5, 2008
How our youthful universe may have wandered the string landscape in search of home—with help from its anti-universe counterpart.
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Hunting for Theories of (Not) Everything
By MARC KAUFMAN • Nov 21, 2008
The architect of "doubly special relativity" wants to probe the quantum nature of spacetime—one step at a time.
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Quantum Darwinism
By ANIL ANANTHASWAMY • Nov 7, 2008
How does objective reality emerge from quantum fuzziness? It's a case of the survival of the fittest.
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Sequence Space: The Final Frontier
By GRAEME STEMP-MORLOCK • Oct 24, 2008
To find out why Earth's biochemistry is so well-suited for life, we need to boldly go where even nature has not gone before.
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The Black Hole and the Babel Fish
By KATE BECKER • Oct 10, 2008
To bring string theory into the lab, you need a “universal translator” to bridge the gap with materials science. Black holes could do the job.
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A Stitch in Quantum Time
By ANIL ANANTHASWAMY • Sep 26, 2008
How do you measure time near a black hole? Pulling apart the threads of spacetime’s fabric could provide an answer—and help unite general relativity and quantum mechanics, in the process.
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Logic Through a Lens
By SCOTT DODD • Sep 12, 2008
To find a theory of quantum gravity, we may have to view reality through a new filter—sacrificing conventional notions of truth and logic along the way.
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The Emperor's New Swindle
By JULIE REHMEYER • Aug 29, 2008
Quantum mechanics is the biggest con trick in physics—according to the collaboration striving to demystify it.
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Quantum Upsizing
By GRAEME STEMP-MORLOCK • Aug 15, 2008
Pushing the quantum-classical limit, an intercontinental collaboration attempts to build the largest ever quantum object.
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When Worlds Collide
By KATE BECKER • Aug 1, 2008
Will we be destroyed in a collision with a neighboring universe? While investigating, one collaboration made a startling discovery.
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A Perfect Match
By WILLIAM OREM • Jul 18, 2008
How do you tie down the physics of the multiverse? With string. One collaboration investigates the partnership of string theory and cosmology.
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Two for the Road
By MARC KAUFMAN • Jul 4, 2008
Two hardy souls work their way through the mathematical thicket of a new model of quantum gravity.
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Predicting The End
By GOVERT SCHILLING • Jun 13, 2008
How does the universe end? One collaboration works to find out. The answer may be in the stars.
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A Blackboard at Brunch
By KATE BECKER • May 30, 2008
In the quest for quantum gravity, one collaboration uses findings from condensed matter physics to take a fresh look at the geometry of space. Is there any?
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Editor's Choice: The Cosmic Puzzle
By KATE BECKER • May 22, 2008
What is Dark Energy? Are we in a true vacuum or a false vacuum? Are early inflation and late inflation related?
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Readers' Choice: High Fidelity
By THE FQXI EDITORS • May 16, 2008
Is nature fundamentally analog or digital (continuous or discrete)?
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Editor's Choice: Wigner’s Gift Horse
By JULIE REHMEYER • May 9, 2008
Is nature completely mathematical?
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Reader's Choice: Philosophy of the Multiverse
By GOVERT SCHILLING • May 2, 2008
On what side of the borderline between science and philosophy are multiverses?
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Editor's Choice: Down the Rabbit Hole
By KATE BECKER • Apr 24, 2008
Do any of our capabilities and experiences inform us that we are not in a computer simulation?
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Reader's Choice: Shining A Light on a Dream
By MARC KAUFMAN • Apr 18, 2008
What is quantum physics fundamentally about?
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Baby Steps
By MIKE PERRICONE • Apr 11, 2008
Why did our universe begin in a low entropy state?
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High Fidelity
By THE FQXI EDITORS • Apr 4, 2008
Is nature fundamentally analog or digital (continuous or discrete)?
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Cosmic Doomsdays: How Will It All End?
An Guide to Freaky – but Improbable – Cosmic Doomsdays
By KATE BECKER • Mar 28, 2008
AN FQXI APRIL FOOL’S DAY SPECIAL REPORT
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Squishy Bedrock
By JULIE REHMEYER • Mar 21, 2008
Can we apply quantum mechanics to the whole universe?
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The Next Ultimate Theory
By MARC KAUFMAN • Mar 14, 2008
What will the ultimate theory (or at least the next one) be like?
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Despairing Still?
By MIKE PERRICONE • Mar 7, 2008
Are there reasons to believe that standard quantum mechanics is insufficient?
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DoubleThink
By KATE BECKER • Feb 29, 2008
How much information is really there in a quantum state?
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Phantasms of Infinity
By JULIE REHMEYER • Feb 22, 2008
Can one define probabilities in an eternally inflating spacetime?
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Down the Rabbit Hole
By KATE BECKER • Feb 15, 2008
Do any of our capabilities and experiences inform us that we are not in a computer simulation?
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Shining A Light on a Dream
By MARC KAUFMAN • Feb 8, 2008
What is quantum physics fundamentally about?
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Wigner’s Gift Horse
By JULIE REHMEYER • Feb 1, 2008
Is nature completely mathematical?
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Philosophy of the Multiverse
By GOVERT SCHILLING • Jan 25, 2008
On what side of the borderline between science and philosophy are multiverses?
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Searching For The Golden Spike
By KATE BECKER • Jan 18, 2008
Is there any hope of experimentally testing quantum gravity?
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As Constant As Polaris
By GOVERT SCHILLING • Jan 11, 2008
Should we expect the “constants of nature” to be constant?
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The Cosmic Puzzle
By KATE BECKER • Jan 4, 2008
What is Dark Energy? Are we in a true vacuum or a false vacuum? Are early inflation and late inflation related?
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Reader's Choice: Surfing the Folds of Spacetime
By SCOTT DODD • Dec 28, 2007
Freelance physicist A. Garrett Lisi may have figured out the most important shape in the universe – other than a surfboard.
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Editor's Choice: Topos Or Not Topos
By GOVERT SCHILLING • Dec 21, 2007
According to Christopher Isham, rephrasing quantum physics in terms of topos theory may lead to quantum gravity. What was the question again?
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Readers' Choice: What Makes Time Tick?
By SCOTT DODD • Dec 14, 2007
Who put the one-way sign on time? Superstring theorist Brian Greene tries to figure out how the universe’s rush from order to chaos gives direction to the fourth dimension.
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Editor's Choice: Through the Looking Glass
By KATE BECKER • Dec 7, 2007
Markus Aspelmeyer hopes his microscopic mirrors and entangled photons will reveal secrets at the interface of classical and quantum mechanics.
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Emergent Theorist
By MIKE PERRICONE • Nov 30, 2007
When it comes to uniting General Relativity with quantum mechanics, Fotini Markopoulou is looking for space in new quantum places.
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Punting in Plato’s Cave
By MIKE PERRICONE • Nov 19, 2007
When it comes to really understanding what’s going on at the microscopic level, Robert Spekkens looks at the quantum world from a realistic view.
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It’s All Relative
By KATE BECKER • Nov 9, 2007
In the search for quantum gravity, Olaf Dreyer is doing something completely different. Measurement problem, meet internal relativity and space-stuff-time.
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In the Key of Symmetry
By MIKE PERRICONE • Nov 2, 2007
When it comes to the smallest scales, perhaps things aren’t as smooth as they seem. John Donoghue seeks a new tune in the key of symmetry.
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Surfing the Folds of Spacetime
By SCOTT DODD • Oct 26, 2007
Freelance physicist A. Garrett Lisi may have figured out the most important shape in the universe – other than a surfboard.
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A Deeper Understanding
By MARC KAUFMAN • Oct 19, 2007
For Roderich Tumulka, the old physicists’ nostrum to ‘shut up and calculate!’ is not good enough. Instead, he wants to understand the reality behind quantum mechanics.
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Building a Better Black Hole
By SCOTT DODD • Oct 12, 2007
Listening to Louis Crane might convince you that little black holes could someday power starships, or that the laws of our universe were fine-tuned by intelligent beings long ago. Just leave the math to him.
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Talking Heads
By KATE BECKER • Oct 5, 2007
What do baseball, penny-flipping tricksters and talking mythological serpents have in common? According to Matthew Leifer, quantum gravity. Or not.
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Topos or Not Topos
By GOVERT SCHILLING • Sep 28, 2007
According to Christopher Isham, rephrasing quantum physics in terms of topos theory may lead to quantum gravity. What was the question again?
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Magic Numbers
By KATE BECKER • Sep 21, 2007
What if the physical constants weren’t? Ekkehard Peik’s ytterbium atomic clock ticks toward a revolution.
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Straightening Out Mind-Bending Measurements
By MIKE PERRICONE • Sep 14, 2007
Measuring time and space on the atomic scale requires quantum rulers and clocks. Gambini and Pullin are up to the challenge.
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Teaching an Old Wave New Tricks
By MIKE MARTIN • Sep 7, 2007
Almost a century ago, Louis de Broglie invented pilot waves – which were soon forgotten. Forty years ago, physicist John Bell resurrected the concept. Today, Antony Valentini’s version may revolutionize quantum mechanics.
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Serious Science. Serious Fun.
By SCOTT DODD • Aug 31, 2007
Hot baths, cold excursions, and stimulating discussions at the Inaugural Conference of FQXi in Iceland.
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Possible Pasts in a Universe of Universes
By JEFF KANIPE • Aug 24, 2007
Is our universe one in an infinite number of pocket universes? Richard Easther plans to apply a new approach to find out.
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The Cat With Two Tails
By WILLIAM OREM • Aug 16, 2007
In the strange world of quantum mechanics, the same tiny object can be in two places at once. Keith Schwab is building a not-so-tiny machine that can do that, too
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Eva Silverstein: The quest to simplify
By MIKE PERRICONE • Aug 10, 2007
String theory predicts there are more than the familiar four dimensions of space-time. But where do those extra dimensions come from? Eva Silverstein is looking.
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Making Waves with Gravity
By JEFF KANIPE • Aug 2, 2007
Xiao-Gang Wen thinks it’s time physicists look outside of Schrödinger’s Box for ways to unify gravity and quantum mechanics.
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Kwiat’s Kwest: Settling – Once and For All – Einstein’s Final Frontier
By MIKE MARTIN • Jul 27, 2007
Paul Kwiat thinks it’s time to close the loopholes and test Einstein’s greatest speculation – the EPR paradox – a difficult task that has never been done successfully before.
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A Dark and Lonely Future
By SCOTT DODD • Jul 20, 2007
Fred Adams can't tell you the score of tomorrow's ballgame, but he can predict where the universe is headed. And it's not an appealing future. Luckily, we've got some time.
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Physicists Reaching Out
By TRUDY BELL • Jul 13, 2007
Today’s physical theories are difficult to understand, even to specialists. Farzad Nekoogar’s Multiversal Journeys takes a stab at explaining them to laypeople.
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Islands in the Sea
By WILLIAM OREM • Jul 6, 2007
The universe around us may be only one of very, very many. If so, how can we test the existence of other universes?
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Deconstructing Everett's Crazy Idea
By STEVE NADIS • Jun 29, 2007
Fifty years ago, Hugh Everett had an idea so crazy it doomed his physics career. Today, Simon Saunders wonders if maybe Everett's idea is crazy enough to be true.
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Not So Local
By TOM SIEGFRIED • Jun 22, 2007
A principle of physics is that what happens here, stays here: “local” events do not influence events far away. Steven Giddings is not so sure.
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To Solve a Cosmic Mystery, FQXi Awardees Think Outside the Box
By MIKE MARTIN • Jun 15, 2007
Justin Khoury and Maulik Parikh dust off an old idea from Ernest Mach – the speed-of-sound guy – to update Einstein’s relativistic view of space and time.
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In Search of Uncertainty
By SCOTT DODD • Jun 8, 2007
Is finding a Theory of Everything an impossible task? For cosmologist Janna Levin, the idea that we might never have all the answers isn't all that depressing.
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Chasing Constant Change
By GOVERT SCHILLING • Jun 1, 2007
Scientists used to think the fine-structure constant, called alpha, was, well, constant. Dmitry Budker races to prove alpha in fact varies � a discovery that would change physics as we know it.
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Eavesdropping On ET
By STEVE NADIS • May 25, 2007
Is intelligent life out there? Avi Loeb looks for leaked transmissions from inhabited planets - not intentional beacons - which broadcast the cosmic announcement: "We are here."
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Mini-Grants, Major Benefits
By JEFF KANIPE • May 18, 2007
Sometimes scientists need just a little bit of money for a small project. But cumbersome conventional grant-review processes can�t always help. Enter the mini-grant lottery.
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Through the Looking Glass
By KATE BECKER • May 11, 2007
Markus Aspelmeyer hopes his microscopic mirrors and entangled photons will reveal secrets at the interface of classical and quantum mechanics.
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Charting the River of Time
By WILLIAM OREM • May 7, 2007
General relativity suggests backward time travel is possible, given the right conditions. Now Ken Olum wants to know whether those conditions are possible.
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In Search Of Other Earths
By JEFF KANIPE • May 7, 2007
Is there life beyond earth? To find out, Sara Seager uses computer models to map possible biosignatures in the atmospheres of planets lurking close to stars.
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What Makes Time Tick?
By SCOTT DODD • May 7, 2007
Who put the one-way sign on time? Superstring theorist Brian Greene tries to figure out how the universe's rush from order to chaos gives direction to the fourth dimension.
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