Rob Seger

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356 followers

Rob's posts

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This could prove invaluable to our medical understanding and abilities but, even if not, it's pretty amazing.

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I love the oatmeal.

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This is amazing. And a really powerful step into a realm of the medicinally enhanced vs poor. Going to be very interesting to see what, as a culture, we decide to do with this kind of power.

A way to revert the adult brain to the "plastic", child-like state that enables fast learning by being able to form new connections quickly has been found. A protein expressed in brain cells called PirB in animals and LilrB2 in humans stabilizes neural connections to protect against loss of learned skills or information, and using a molecule called an ectodomain can interfere with its functioning enabling the more "plastic" fast-learning state to return. Ectodomains are membrane protein that normally extend extends through the membrane of a cell into the extracellular space outside the cell.

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As she mentions, people write this experience off because she was 'extreme' in her beliefs (literal is a far more accurate a word). What she doesn't realize is that there's an additional mind fuck going on for women who aren't living under these extremes: they're failing to live as righteous examples.

Her hell isn't unique to extremists. It's as common as church on Sunday.

http://www.alternet.org/belief/how-playing-good-christian-housewife-almost-killed-me?paging=off

Her hell isn't unique to extremists. It's as common as church on Sunday.

http://www.alternet.org/belief/how-playing-good-christian-housewife-almost-killed-me?paging=off

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I wish there were a way to gift the underlying lesson here to everyone in the world: correlation is not causation. Learn it, love it.

http://www.tylervigen.com/

http://www.tylervigen.com/

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Brightened my morning :)

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Another fantastic experience with Puget! If you're in the market for a new machine I strongly recommend checking them out. They are far and beyond the best company I've ever bought a computer (desktop or laptop) from.

http://www.pugetsystems.com/

http://www.pugetsystems.com/

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Always nice to know that people you respect get lost too sometimes.

Did you ever feel your brain is about to break? It happens not just to beginners in math, but to

So, in case you feel frustrated with math, let me share one of my own frustrations. You'll see you're not alone!

Right now I'd love to understand something a logician tried to explain to me at lunch a while back. His name is Boris Zilber. He's studying what he calls 'logically perfect' theories - that is, lists of axioms that

Now, Gödel's incompleteness theorem means our usual theory of natural numbers

0, 1, 2, 3, ...

together with addition and multiplication is far from 'logically perfect' in this sense. In fact, only

If we've got an infinite-sized structure, the most we can hope for is that

And this actually happens sometimes. It happens for the complex numbers! Zilber believes this has something to do with why the complex numbers show up so much in physics.

More precisely, say λ is some size - that is, some cardinal, which could be finite or infinite. A list of axioms in first-order logic is called

According to Zilber - and I'm sure he knows what he's talking about here - the axioms for the complex numbers together with addition and multiplication are uncountably categorical.

Zilbert likes lists of axioms that are uncountably categorical so much that he calls them

Somehow 'logical perfection' in Zilber's sense connects logic to some concepts from geometry! But I don't understand any of the details. And when I start studying them, I feel like Gollum here.

• Boris Zilber, Perfect infinities and finite approximation, in

https://people.maths.ox.ac.uk/zilber/inf-to-finite.pdf.

#spnetwork #logic

*everyone!*So, in case you feel frustrated with math, let me share one of my own frustrations. You'll see you're not alone!

Right now I'd love to understand something a logician tried to explain to me at lunch a while back. His name is Boris Zilber. He's studying what he calls 'logically perfect' theories - that is, lists of axioms that

*almost completely determine*the structure they're trying to describe. He thinks that we could understand physics better if we thought harder about these logically perfect theories.Now, Gödel's incompleteness theorem means our usual theory of natural numbers

0, 1, 2, 3, ...

together with addition and multiplication is far from 'logically perfect' in this sense. In fact, only

*finite-sized*mathematical structures can be completely determined by finite lists of axioms in ordinary logic (so-called 'first-order logic').If we've got an infinite-sized structure, the most we can hope for is that

*after we specify the size of the structure*, the axioms completely determine it.And this actually happens sometimes. It happens for the complex numbers! Zilber believes this has something to do with why the complex numbers show up so much in physics.

More precisely, say λ is some size - that is, some cardinal, which could be finite or infinite. A list of axioms in first-order logic is called

**λ-categorical**if it's obeyed by a unique structure of size λ. And a guy named Morley showed that if a list of axioms is λ-categorical for some uncountable λ, it's also λ-categorical for*all*uncountable λ. I have no idea why this is true. Bu such lists of axioms are called**uncountably categorical**.According to Zilber - and I'm sure he knows what he's talking about here - the axioms for the complex numbers together with addition and multiplication are uncountably categorical.

Zilbert likes lists of axioms that are uncountably categorical so much that he calls them

**logically perfect theories**. And he writes:**There are purely mathematical arguments towards accepting the above for a definition of perfection. First, we note that the theory of the field of complex numbers (in fact any algebraically closed field) is uncountably categorical. So, the field of complex numbers is a perfect structure, and so are all objects of complex algebraic geometry by virtue of being definable in the field.****It is also remarkable that Morley's theory of categoricity (and its extensions) exhibits strong regularities in models of categorical theories generally. First, the models have to be highly homogeneous [....] Moreover, a notion of dimension (the Morley rank) is applicable to definable subsets in uncountably categorical structures, which gives one a strong sense of working with curves, surfaces and so on in this very abstract setting. A theorem of the present author states more precisely that an uncountably categorical structure M is either reducible to a 2-dimensional "pseudo-plane" with at least a 2-dimensional family of curves on it (so is non-linear), or is reducible to a linear structure like an (infinite dimensional) vector space, or to a simpler structure like a G-set for a discrete group G.**Somehow 'logical perfection' in Zilber's sense connects logic to some concepts from geometry! But I don't understand any of the details. And when I start studying them, I feel like Gollum here.

• Boris Zilber, Perfect infinities and finite approximation, in

*Infinity and Truth*, World Scientific, Singapore, 2014,https://people.maths.ox.ac.uk/zilber/inf-to-finite.pdf.

#spnetwork #logic

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I sincerely hope this works as well as it sounds on paper. Beauty and utility all in one place? I'm always up for that!

**It’s not a fairytale: Seattle to build nation’s first food forest**

Seattle's food forest will be filled with edible plants, and everything from pears to herbs will be free for the taking.

(take part) Seattle’s vision of an urban food oasis is going forward. A seven-acre plot of land in the city’s Beacon Hill neighborhood will be planted with hundreds of different kinds of edibles: walnut and chestnut trees; blueberry and raspberry bushes; fruit trees, including apples and pears; exotics like pineapple, yuzu citrus, guava, persimmons, honeyberries, and lingonberries; herbs; and more. All will be available for public plucking to anyone who wanders into the city’s first food forest.

“This is totally innovative, and has never been done before in a public park,” Margarett Harrison, lead landscape architect for the Beacon Food Forest project, tells TakePart. Harrison is working on construction and permit drawings now and expects to break ground this summer.

The concept of a food forest certainly pushes the envelope on urban agriculture and is grounded in the concept of permaculture, which means it will be perennial and self-sustaining, like a forest is in the wild. Not only is this forest Seattle’s first large-scale permaculture project, but it’s also believed to be the first of its kind in the nation.

“The concept means we consider the soils, companion plants, insects, bugs—everything will be mutually beneficial to each other,” says Harrison.

That the plan came together at all is remarkable on its own. What started as a group project for a permaculture design course ended up as a textbook example of community outreach gone right.

http://www.thrive-living.net/2014/07/its-not-fairytale-seattle-to-build-nations-first-food-forest.html

#foodforest #seattle #permaculture #foodforeveryone

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If you're interested in security/malware, you might be interested in a blog post I just finished up. You can skip to the end for the amusing anecdotes if you want - you won't hurt my feelings ;)

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