Search FQXi

If you are aware of an interesting new academic paper (that has been published in a peer-reviewed journal or has appeared on the arXiv), a conference talk (at an official professional scientific meeting), an external blog post (by a professional scientist) or a news item (in the mainstream news media), which you think might make an interesting topic for an FQXi blog post, then please contact us at with a link to the original source and a sentence about why you think that the work is worthy of discussion. Please note that we receive many such suggestions and while we endeavour to respond to them, we may not be able to reply to all suggestions.

Please also note that we do not accept unsolicited posts and we cannot review, or open new threads for, unsolicited articles or papers. Requests to review or post such materials will not be answered. If you have your own novel physics theory or model, which you would like to post for further discussion among then FQXi community, then please add them directly to the "Alternative Models of Reality" thread, or to the "Alternative Models of Cosmology" thread. Thank you.

Forum Home
Terms of Use

Order posts by:
 chronological order
 most recent first

Posts by the blogger are highlighted in orange; posts by FQXi Members are highlighted in blue.

By using the FQXi Forum, you acknowledge reading and agree to abide by the Terms of Use

 RSS feed | RSS help

Antony Lisi: on 5/2/07 at 22:02pm UTC, wrote Hi Anthony, I was getting a lot of deep thinking done in Maui, but the...

Anthony Aguirre: on 5/2/07 at 0:04am UTC, wrote Garrett, Thanks for this inspiring post! However, as part of the FQXi...

Antony Lisi: on 4/19/07 at 18:55pm UTC, wrote We've had a series of late season storms sweep through Tahoe this past...


Robert McEachern: ""At least that's the premise." That's the problem. "the theorems that..." in Alternative Models of...

Malcolm Riddoch: "@Robert: ""This latter, Ψ(U), can't describe a 'drug test' can it?" For..." in Alternative Models of...

John Cox: "Lorraine, I briefly described the relationship of mass to inertia..." in Emergent Reality: Markus...

Lorraine Ford: "John, I would say that you need to think what you mean by “physical..." in Emergent Reality: Markus...

Lorraine Ford: "Re "I tend to speed-read then review before scoring after reading a good..." in Undecidability,...

John Cox: "George, We shouldn't conflate contradiction with inconsistency. QM has a..." in Watching the Watchmen:...

John Cox: "Georgi, by and large I agree. Near the end of the discussion panel,..." in Watching the Watchmen:...

click titles to read articles

First Things First: The Physics of Causality
Why do we remember the past and not the future? Untangling the connections between cause and effect, choice, and entropy.

Can Time Be Saved From Physics?
Philosophers, physicists and neuroscientists discuss how our sense of time’s flow might arise through our interactions with external stimuli—despite suggestions from Einstein's relativity that our perception of the passage of time is an illusion.

A devilish new framework of thermodynamics that focuses on how we observe information could help illuminate our understanding of probability and rewrite quantum theory.

Gravity's Residue
An unusual approach to unifying the laws of physics could solve Hawking's black-hole information paradox—and its predicted gravitational "memory effect" could be picked up by LIGO.

Could Mind Forge the Universe?
Objective reality, and the laws of physics themselves, emerge from our observations, according to a new framework that turns what we think of as fundamental on its head.

January 24, 2020

CATEGORY: Blog [back]
TOPIC: Deferential Geometry [refresh]
Bookmark and Share
Login or create account to post reply or comment.

Blogger Antony Garrett Lisi wrote on Apr. 19, 2007 @ 18:55 GMT
We've had a series of late season storms sweep through Tahoe this past week. Flurries of snow swirl around briefly, then settle and melt in the spring sun. During a break in the clouds today C and I hiked up the fire road behind our house to watch the storm clouds chase each other around the lake.

This world of ours is a remarkably beautiful place. Perhaps it only seems beautiful to us because we've evolved to live here, but the rich complexity of it all is inarguable, whatever the perspective. On the largest scale possible for us to see, the universe looks like nothing but geometry -- the curving spacetime of general relativity, punctuated by matter. Closer in, the matter has formed into galaxies, composed of mysterious dark matter and stars, with planets and other chunks of burnt-up star stuff circling about and between them. On our personal scale, the physical world is dominated by the chaos of our environment and biology, with complex interactions between an infinite variety of living things. But a closer look shows this biology to follow many of the same patterns, with intricate dances of biochemistry repeated within each cellular building block. And this chemistry is made up of molecules composed from only a hundred or so different kinds of atom. And each of these atoms is built from a handful of particles, which, as far as we can tell, are each exactly the same. But what are they?

As we look deeper, the world appears to be built from fewer and simpler building blocks, with its every motion orchestrated by mathematics. We clearly live in a mathematical universe. But our home is not composed of random mathematics -- if it was, things wouldn't look any more elementary at smaller scales. The mathematics has to defer to what is real, to what we see with our experiments, and not just be stuff someone thought would be fun to make up. The universe should be described by a fairly uncomplicated bit of math that we just haven't figured out yet.

By this measure the most successful bit of mathematics staring us in the face is Einstein's geometric description of the universe on the largest scale. If the whole universe, down to the smallest scale, is going to be described by a unified, simple bit of mathematics, it's going to have to be geometry all the way down. The smallest subatomic particles are themselves going to have to have a geometric description, as a bit of deferential geometry.

So when I look out at the clouds over the lake, under a patch of beautiful blue sky, the snow falling in the distance, with wind rustling the pine needles nearby, and Blue Jays hopping between branches, that's what I see at play underneath it all -- whirls of geometry. And when I return home, to play with equations, that's what I look for.

Bookmark and Share
this post has been edited by the author since its original submission

report post as inappropriate

FQXi Administrator Anthony Aguirre wrote on May. 2, 2007 @ 00:04 GMT

Thanks for this inspiring post! However, as part of the FQXi administration, I am a bit concerned about your FQXi grant . My reading of the report from the review committee was that the money was specifically for thinking deep thoughts about physics while sitting on beach in Hawaii, whereas here you seem to be thinking physics while sitting and viewing Lake Tahoe. I will have to ask the ad-hoc committee to look into this...

Bookmark and Share
report post as inappropriate

Blogger Antony Garrett Lisi wrote on May. 2, 2007 @ 22:02 GMT

Hi Anthony,

I was getting a lot of deep thinking done in Maui, but the mountains here in Tahoe -- where I'm spending a lot of time in the lab -- provide an ideal environment for working on gravity. I hope the committee will consider this when deciding whether I'm spending the funds properly.

Bookmark and Share
this post has been edited by the author since its original submission

report post as inappropriate

Login or create account to post reply or comment.

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.