Physics Question for mrkelley

[Here's Fanny!]

Anybody else please don't read until you answer the QOD. This doesn't really have to do with any QOD question, but I do make reference to things that are parts of answers.

Everything I know about quarks I learned from Stephen Hawking. So, I go grab my Brief History and get to work. I could have sworn The Universe in a Nutshell was on the same shelf, but I can't find it!

Oddly enough, Hawking doesn't say all that much about quarks themselves in the book. Plus, I'm thinking that a lot of stuff has changed since then, so I'm not going to answer the QOD until I find Nutshell, which is much newer.

One of the reasons I want to go from books is:

Spoiler

I googled a couple words from the book and ended up on a Wikipedia page that says the top quark was discovered in 1996, but Hawking mentions top quarks in Brief History and it was written in 1987! I think he did at least one updated version a few years ago, but my copyright is 1988, so it's the original softcover.

So how does this work? When they found the bottom in the 70s, they knew there must be a top so they just assumed for 20 years until they found it? Or is Hawking just that incredible and omniscent that he already knew it? Or is stuff on the internet just wrong, which is why I'm using my Hawking books as my source, if I can.

[mrkelley23]

The Clintonesque answer: it depends on what your definition of "discovered" is.

Originally, there were only three quarks postulated, as all of "normal" matter could be explained pretty easily by them. But when exotic matter began showing up in high-energy collisions, it became clear that there were other types of quarks, too. The trouble is, no one's ever "seen" a quark -- it's not possible to do. Instead, physicists conduct high-energy collisions, then examine a computer track of the resultant debris to find the "footprints" of individual particles.

The top quark was one of those particles that "had" to exist, but no direct evidence was found, not even those footprints, until a collider was built big enough to provide the energies needed. It actually produced some interesting political ramifications, as one of the explanations for why the US needed the never-built Superconducting Supercollider was to win the "Race for the Top."

The top quark was eventually "found," i.e., direct evidence discovered, in 1996; but everybody who was anybody in high energy physics knew it existed long before that. That's the kind of knowing that religionists confuse with faith -- and in doing so, diminish their own faith.

BTW, I didn't read Universe in a Nutshell, but since Hawking is usually about trying to make science accessible, he may not go into enough detail for this particular QoD.

[Here's Fanny!]

Your explanation was pretty much what I surmised. Thanks!

BTW, I didn't read Universe in a Nutshell, but since Hawking is usually about trying to make science accessible, he may not go into enough detail for this particular QoD.

The Universe in a Nutshell is a little more in depth but less sweeping than Brief History. It's also a lot fancier, with coloured glossy pictures and whatnot rather than the b&w illustrations of the the latter.

He definitely doesn't go into enough detail for a google QOD, but that's the beauty of him, in my opinion. I think that most smarty pants (in whatever field) find it difficult to get something across to the masses and, in the process, sound conscending and/or elitist (sometimes on purpose, sometimes because they can't help it).

The brilliance of Hawking is that he has a mind that can grasp and create such amazing things, but he can explain it so that the dumbys of the world like me can learn something from him and enjoy doing so.

He just gives enough of the basics of things like quarks so that you'll understand the more complicated stuff that he's leading up to. Plus he has a wonderful sense of humour. The result is that you're reading along and pretty soon you're reading about particles and string theory and Heisenberg Principles and you just stop and think, "whoa! I'm reading about particles and string theory and Heisenberg Principles! And I'm not only reading about them, I'm understanding what I'm reading!"

With the exception of A Tree Grows in Brooklyn, I think I've read A Brief History of Time more than any other book and I always find something new or get a different understanding (you should see my copy, it's so beat up it's silly) than I had before. He even made me want to give Newton's Principia a go. So to me, Brief History is the gold standard. The only one that comes close is The Elegant Universe.

I might just look up some stuff to get the answers to the QOD, but I like to understand why things are the answer rather than just looking for keywords and finding the answer (for subjects in which I'm interested, anyway). So thanks for the QOD subject, because it's been too long since I've given Hawking a read and now I'm of a mood to do so.