18/04/23 09:45:47
@daily
Is this gonna be one of those things I regret not learning earlier? What’s the point in this thinking, I can only learn it when I learn it. Sometimes I feel I would have been on a different path if I could have engaged with Science like I do now earlier in my life. I guess not everyone can be that lucky, it’s also not really helpful and relies on comparison of “where you’re supposed to be in your development” or something. Just be content with learning whatever it is now.
Dimensional Analysis
https://www.youtube.com/watch?v=3gxNrc_EEN8
- There is a difference between and unit and a dimension.
- Physical quantities are measured in units.
- The dimension of the physical quantity is independent of the unit.
- Grams and pounds are both units of the dimension mass.
- I would see dimension as a degree of freedom of the physical quantity.
- There are 5 main dimensions: mass, time, temperature, length and charge.
- No matter how you measure the physical quantity velocity is has dimensions length/time.
- Example has the goal of slowing the rover (landing on mars) to exactly 90 m/s.
- Goal is to define size of parachute that reaches 90 m/s terminal velocity.
- Determining variables:
- Dependent, the variables we wish to constrain by our parachute design. This is the terminal velocity.
- Independent, what variables affect this dependent? Diameter of chute, mass of rover, atmospheric density, gravity.
- Terminal velocity now becomes some function of these independent variables.
- The function must combine the variables in some way to have the same dimensions as velocity.
- Dimensional analysis tries to find the most general form of this function.
- Step 1. Distill variables into fundamental dimensions (M, L and T in example) so that theres no repetition of physical quantities measured.
- Step 2: Express M, L, T in terms of variables. So for each dimension determine the variables that are defining that dimension in our problem.
- Step 3: Create dimensionless versions of the variables.
- One thing I’m noticing today is that it feels good to get the stuff I really need to do done in the morning and then some of the more minor stuff (like my own reading in the afternoon).
- Then having to do literally nothing for the evening, even though sometimes the my own stuff doesn’t feel that hard (although it can be).
- In Succession, there’s a constant pining for glory of some sort. They’re not really happy, like, ever. I wonder how prevalent the notion of deriving a narrative for yourself influences theses things. It’s part of the reason I’d like to learn more about personality types, in Noise apparently Kahneman says we don’t really understand how different our beliefs (or priors) actually are. I would could personality encapsulate some of that.
- It’s fascinating how they are so warped by this game they’re in. Definition of a random incentive moloch just dictating random shit.