Comments on: Why Stuff is Hard

By: The uselessness of physics in fundamental research at Freedom of Science

The uselessness of physics in fundamental research at Freedom of Science — Fri, 31 Aug 2007 23:53:18 +0000

[...] Here a physicist ruminates about the hardness of matter:1 The Pauli exclusion principle is probably involved at some level for all of them, though it could be obfuscated by other effects. From my reading, I was able to derive the hardness of one simple, but undeniably hard, material: metal. … [...]

By: Michael D. Cassidy

Michael D. Cassidy — Mon, 13 Aug 2007 16:45:00 +0000

Thanks for this post, though there are parts that went by me, it was wonderful to read.

By: Kea

Kea — Sat, 11 Aug 2007 22:17:56 +0000

It’s neither stringy or loopy because these are failed attempts at QG.

By: jpivarski

jpivarski — Sat, 11 Aug 2007 22:14:17 +0000

Hi all, thanks for your comments! I had to choose a level for this article, and I chose to write it for interested mathematicians, and myself five years ago. I can’t write about the specifics of soft matter, glass, and water, because I don’t know much about them. However, I also want to understand this subject in general— it’s disturbing that most things in the world feel solid, but we need a separate explanation for each of them. I think I’ve found a truly general argument (see my next post), and that one necessarily glosses over details.

I, too, would like to learn if water is stringy (or loopy). Is it?

By: Kea

Kea — Sat, 11 Aug 2007 00:04:24 +0000

Agreed, Jonathon, but would you mind clarifying the mysterious comment:
The question of loops versus strings in water were debated in the past couple of years between Los Alamos people and other people. ??

By: Jonathan Vos Post

Jonathan Vos Post — Fri, 10 Aug 2007 21:39:15 +0000

I think this sweeps some hard problems under a soft rug.

We know that crystals of various substances and crystallographic point groups exist and are stable in 3+1 dimensional space (x,y,z,t). But only in the past decade or so can we mathematically suggest why that stability is so.

Most solid matter is not crystalline. Except for little bits of tooth and bone, we ourselves are squishy wet soft stuff.

Why is soft matter stable?

Why are DNA and RNA and proteins in protoplasm stable?

Even more to the point: what is the actual structure of liquid water, and why is it stable? The question of loops versus strings in water were debated in the past couple of years between Los Alamos people and other people.

Why is glass hard?

These are serious questions.

By: Rueben

Rueben — Fri, 10 Aug 2007 20:48:20 +0000

…way too long an explanation for us dummies.

“If you can’t explain it to your grandmother — you don’t understand it.”

{– A. Einstein}

By: Kea

Kea — Thu, 09 Aug 2007 21:55:33 +0000

Don’t worry - it’s a fantastic post. We’re just speechless at your blogging skills. I especially liked the point about quantized masses.