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sidek

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I miss IRC deeply. We had an internet with an amazing, people-run, free, chat network.

And we replaced it with corporate things like facebook messenger/discord where you're the product.

Your argument is not supported by data. The NHS and Canada's universal healthcare systems have been around for decades.

Yet there is no evidence to suggest the factors you describe have ever been part of the public discussion in those countries. And the US is the country with the most draconian drug laws in the Anglosphere.

As a result, lots of recent work is being done in the algebraic setting (rather than analytic), where the foundations are on much firmer footing.

Being algebraic symplectic is a much stronger condition than analytic symplectic, but is still interesting enough (and, for geometry related to linear algebra problems, as is often relevant in CS, is not a very strong restriction at all.)

Lost in Math 8 years ago

To me, the criticism of the Science review that this book offers no alternative paths forward is very strong. This is because when blundering around in the darkness to find truth, there are no good algorithms. If you could tell a high energy theorist a better algorithm to find good problems to work on, they would listen. But if all you can do is point out that their algorithm is suboptimal: well, sure. Of course it's suboptimal: we know, we just have no better search algorithms in physics-theory-space.

Woit and company seem really invested in smearing high energy theory in front of popular audiences. A book-long `look at the fact that this algorithm is really slow!!!' is a sigh-worthy addition.

It's well acknowledged in the field that SUSY, string theory, etc. are very incomplete ideas. No one is saying they have the full story, and I don't think anyone expects to have the full story anytime soon.

So what have people been doing?

1) People have been expositing our `best guess' theory, which /is/ string theory. We have really good tests of quantum field theory, and really good reasons to think that `the most natural' generalisation is string theory. We're not cocky enough to claim that string theory /is/ the generalisation, just that it's a really good candidate and isn't it worth spending a vanishing fraction of GDP to explore it and see how good of a candidate it really is? Like, an incredibly larger amount of money is spent on innovating ways to get people to look at advertisements. It doesn't seem like there is a high bar to pass to justify the existence of studying this stuff.

Of course, a lot of effort goes into finding better guesses. Supersymmetry has been under the gun since the LHC turned on, and tons of effort has been and is spent thinking about the alternatives. Supersymmetry just remains a strong enough idea in comparison to the alternatives people have proposed that people think it's the best idea to explore. And as time goes on and supersymmetry looks weaker and weaker, more people do spend time looking for good alternatives.

2) People have been using tools from string theory to tell us about ordinary quantum field theories. Dualities like ADS/CFT are huge right now. Lots of really good ideas have come from high energy theory in recent years. ADS/CFT is a string-theoretic duality which teaches us a lot about statistical mechanical systems, things that definitely are testable. So string theory has been testably productive, as applied to the study of quantum field theories and statistical mechanics.

3) Also, the idea of topological quantum field theory is a recent innovation of high energy theory, hardly fully explored, and has been hugely important for modern mathematics.

I think these activities are pretty reasonable.

In fact, current elite US college admissions seem to select for people who vote Democrat well enough. It would be hard to increase that percentage very much. Just look at the political affiliation reported by e.g. Harvard students. If anything, I would think that an institution which tested for wisdom might shift conservative a percentage point or two.[ Not because I think conservatives are necessarily more moral in the US; but because I think more conservatives are religious and churches teach the language of virtue, which probably at least better tells you what the 'right' answer on wisdom tests is, whether you live that answer or not.]

Imperative Haskell 9 years ago

The answer, as you point out, is that CP violation implies T violation. Experimentally testing T violation is much, much harder, and I don't think has really been done in many systems (look at Fitch and Cronin's work for an example), but we know CP violation implies it. So it's there. Or at least, to our best knowledge, it's there -- T violation is not very well understood.

Imperative Haskell 9 years ago

Entropy is not due to the equations of our universe, but rather the initial conditions. So the asymmetry might be apparent but the equations might still be symmetric. Related is the idea of spontaneous symmetry breaking.

Of course, we don't have time symmetry in the equations anyway because of the weak force. But because the weak force is weak//doesn't matter much for the physics of many systems, we can often write the equations of physics as a time-symmetric term which essentially decides the motion plus a very small time-asymmetric term. So we can deal with the small term using techniques like perturbation theory, and use time symmetry for the rest.

I think the main difference (speaking from the biased perspective of a Canadian) is that US border guards seem to want to get angry. Whilst Canadian guards have a "what we're doing is necessary, but we want to be nice" attitude.

Unfortunately Canada's awful security policy comes because we need to be "up to US standards", or else we risk huge barriers being put in the middle of our trade relationship due to US paranoia. And economically, Canada is totally dependent on trade with the US.

Diversity is no excuse for America's failures. Your nation is not as much an outlier in diversity as you would like to believe, and in the domain of health care you need only look north to Canada to see that this argument is nonsense.

You're absolutely right. Good emotional state is probably the key factor in combating addiction. Yet it's important to remember that there exist other factors at play in addiction, and that we should target them too. For instance, addiction to alcohol seems to have some genetic factors. In some genetic lines, almost every person with a low emotional state might be at huge risk for addiction. And in others, almost no one might be at risk. We need to also understand why that is, and combat that, too.

The problem, like the author points out, is that you can build all the rail you want -- but you need to make sure that it goes to places dense enough to support it. When cities fail to do this, you get that ridiculousness.

Yeah, I often say "in Massachusetts" when people ask where I go to school, when I'm back home. Everyone seems to think this is a mark of how snooty Harvardians are.

But often when I did just say "Harvard", it became a big deal. Not always, but often.

It can make social situations weird. I socialise with a lot of people who are in the trades. I've had more than a few conversations killed when the person I'm talking with finds out I go to Harvard. Suddenly (again sometimes, not always) the person feels embarrassed because they aren't an intellectual, or unrefined, or something, and the conversation gets awkward fast.

It can also make some people just overestimate or overcare for you. I used to volunteer for a political party. The local organiser was nice and treated me well, like he treated everybody, but once he found out I went to Harvard he decided to give me double the attention, plus the cushy assignments, I guess in hopes of retaining me-- when really I just wanted to do the door knocking and phone calling like everyone else.

I wish that the name of the place I go to school didn't have cultural cachet far beyond its worth and that I could always just say it. But it does, especially where I'm from, where not many people have been anywhere near an Ivy. So sometimes I decide to not risk triggering this weird overblown cultural image, because I just want to be myself and not "that guy who goes to HARVARD". Many of my friends feel similarly. I don't know how this desire counts as noblesse oblige.

Yup. I go to an ivy and many of my best friends are construction workers or service workers who will likely never attend college. It's because I wasn't sheltered (nor particularly wealthy as a kid).

And when you're there, talk to people. Not just ones who will help you climb the social ladder in whatever elite clubs and orgs you want to join. People of all stripes. It's a much more diverse group in every way than the author describes.

Honestly it sounds like the author was elitist and sheltered as a kid. And now they've realised this, but have decided to blame it on their university rather than deal with the fact that it was their own personal fault.

My most distinct memory of early education is my grade seven teacher yelling at me, saying that he never wanted to see me read a book in his classroom ever again. I used to read books in class after I finished whatever trivial in-class work we had... apparently, this was more annoying to him than the kids who didn't do their work and loudly talked about their drug consumption.

But the motivation behind dark matter is deeper than its gravitational observations. For instance, almost all particles physicists believe the standard model of particles is incomplete. No one is really sure exactly what we need to add to the standard model, but it turns out that if you add things to it in any sensible way, you almost always get things that look like they could explain dark matter.

So, it's more: particle physicists all believe the real theory has this aspect; when we look at gravity it looks like it had this aspect; therefore we should probably find a way to modify our theory so it has this aspect.

The major reason we haven't been able to go further than this is because we haven't been able to pin down exactly what these new particles are. Particle experiments are /hard/ (see:LHC), and it might take a long time.

More realistic might be a long-term preparation scenario in which we send a first wave of robots to set up some solar panels and run them to store H2 and O2 for a couple of decades. We won't have gained energy necessarily, but we will have stored it in large enough amounts that early colonisation will have extra energy if it needs it.

The problem (not having a condensed matter background, so my answer might not be entirely right) is that we can't solve the Schrödinger equation exactly for many-atom systems.

So we need to approximate our solutions to be able to get a good idea of what properties a material will have. Our approximations are pretty good and we have a decent idea of when some things superconductor. But our theories of superconduction aren't yet perfect, and sometimes the approximations can fail//generate behavior unexpected by our theories.

You speak of the Ivies as a group which has wronged you, but I don't necessarily think your experience is representative of the group as a whole.

Certainly my experience at another Ivy has been that this one goes out of their way to make sure students are funded, and will usually accept even egregiously late paperwork with no reduction in financial aid.

But if Americans take the perspective that their premier universities should contribute tax dollars, whilst other countries fund their universities, American universities will have marginally less resources. This will compound, because international moguls who can donate to a good school in country A (and have 20℅ taxed off the top) or in country B (and have none taxed) might well prefer country B.

The end result is a plummet in the Ivy League's international standing. Academics are remarkably focused on their research; prestige and nation matter little to many of thr top ones. What attracts academics are resources and colleagues. Without resources, the colleagues become worse, so both wither. Suddenly you'll have American politicians wondering why their schools aren't the best anymore.

Honestly, as a Canadian, this is what I find so dumb about our urban planning. People demand adequate house spacing, backyard space, etc... Only for it to be usable for 4 months of the year. Meanwhile, all that dead space makes our cities unwalkable in the other 8 months. I guess people are just so used to having to drive everywhere that they don't see how else it could be.

Honestly, as a Canadian, this is what I find so dumb about our urban planning. People demand adequate house spacing, backyard space, etc... Only for it to be usable for 4 months of the year. Meanwhile, all that dead space makes our cities unwalkable in the other 8 months. I guess people are just so used to having to drive everywhere that they don't see how else it could be.