About a year ago, I was working on a machine learning problem. I had a lot of training data I wanted to manually classify, so I put together a Mathematica interface for the data that would let me browse the training set and assign classifications from a USB gamepad. It was pretty straightforward... only took an hour or two to implement, and it sure beat classifying with mouse clicks!
You've got to get some statistical mechanics on this list. One would have a very difficult understanding quantum field theory without at least some experience considering phase transitions in more familiar settings.
I used to be an experimental particle physicist, so I've certainly got some bias here, but I really think learning particle physics and the Standard Model is worth while. Halzen and Martin is a VERY good textbook and an excellent preparation for studying quantum field theory.
Yes, it is expensive. But it is very well written and thorough.
Also, I think it's always important to mention in these conversations that most physicists don't take string theory seriously. From the outside, it looks like the exciting frontier of modern physics. But that's more about Brian Greene's skill in marketing himself than string theory's explanatory value.
That being said, the Fabric of the Cosmos is a good layman's survey of the modern physics landscape:
More work to configure, but also works on Linux. There's a wonderful ncurses interface called ncmpc as well. mpd + ncmpc has been my iTunes in a terminal window for years.
Z bosons decay into a lepton (electron, muon, or tau particle) and its anti-particle. Those decay products pass through a magnetic field and eventually collide with a material that absorbs all of their energy. Measuring the path of the leptons (in particular, the deflection caused by the magnetic field) allows you to determine their momentum. The intensity of the collision with the stopping material is used to determine the energy.
Knowing the energy and momentum allows one to calculate the path. Gravitational forces are also acting on those particles, and any changes in their paths caused will change the final calculated mass.
With known equations, then yes, dimensional analysis is essentially just a form of bookkeeping that helps you verify your math as you go.
But once you get into using quantum field theory to study new systems, the standard approach is to concoct a conservation of energy equation by summing terms, where each term is a combination of the system's variables with units of energy.
From there, you can discretize the coordinates and predict the existence of various particles (or pseudo-particles, depending on what kind of system you're describing) and their dynamics.
I couldn't agree more. Grant money is precious. Instead of spending three or four grad student salaries to pay a programmer a competitive wage, it makes more far more sense to fund three or four students on research assistantships where they have time to learn Perl.
Well, if 18 year olds are good soldiers because they aren't fully mature, why not allow 14 year olds to be soldiers? Or 8 year olds for that matter... after all, as African warlords have shown, even a small child can be a great soldier with enough cocaine.
I'm so pissed that I upvoted you, now that I've seen your contributions to other threads. But hey, you managed to finally make a comment that didn't call someone gay or disparage gay people... maybe some positive reinforcement will help you grow up. Good job!
But yes, I can't for the life of me understand why someone would want to use TwinLisp.
Yes, the parents of Mitchell Henderson are indeed pussies. It's unbelievable that they could be so thin skinned about a few harmless prank calls... come on, it's only the suicide of their child we're talking about!
Being outraged by a problem is not synonymous with wanting the government to fix it. Bringing attention to a problem is
not synonymous with begging for new laws.
No. Even though particle physics gets all the media attention, theories like this (and string theory for that matter), are shallow in comparison to statistical mechanics and thermodynamics.
It's exciting to find out what the smallest building blocks look like, but all the real structure in the universe arise from the interactions... and statistical mechanics addresses the interactions at all scales.
Modifications to our understanding of the smallest scales will trickle up to stat mech and thermo, but statistical mechanics is the true heart of physics.
There are two ways you can look at an aphorism such as this "brick wall" business. Either:
1. These words of wisdom are a useful way to motivate myself when things are rough.
2. These words of wisdom should be used as a criteria for judging other people.
I think it's a damn nasty metaphor only when you apply it to someone other than yourself. Let me put it this way... we should celebrate those people who have pushed past whatever tremendous barriers they found in their way, but we should never look down on those who tried and failed.
Probability of success in many areas of life is at least partially dependent on attitude... and as cheesy and vapid as they may sometimes sound, I will take whatever comfort and confidence I can from these sorts of inspirational messages when I come across them.
http://daringfireball.net/linked/2011/09/30/the-talk-show-61