Yesterday was hard.
I'm in some courses all this week, and I don't understand anything that 3 of the 4 speakers say. And I've just met the new PhD student of the department, and he's really smart and he's understanding most of the things. And on top of that my advisor is asking me to finish a big amount of writing. I feel really stupid and discouraged.
So, list of positive things to take into account this week:
- All of the courses are about PDEs and not Dynamical systems (which is my research topic). It's normal to not understand most of them.
- It is a great opportunity to see how people of other topics work, and what are they interests. You don't need to understand everything perfectly. Let go and enjoy.
- I learned a lot from yesterday's poster session, and from other students.
- Next year I would have a very smart PhD partner from who I could learn a lot.
- I am a slow-learner when understanding new topics, and that is okay. I could have other qualities that make me a good mathematician.
A 392 year-old shark found in the Arctic. This guy was wandering the oceans back in 1627.
“You ruin your life by desensitizing yourself. We are all afraid to say too much, to feel too deeply, to let people know what they mean to us. Caring is not synonymous with crazy. Expressing to someone how special they are to you will make you vulnerable. There is no denying that. However, that is nothing to be ashamed of. There is something breathtakingly beautiful in the moments of smaller magic that occur when you strip down and are honest with those who are important to you. Let that girl know that she inspires you. Tell your mother you love her in front of your friends. Express, express, express. Open yourself up, do not harden yourself to the world, and be bold in who, and how, you love. There is courage in that.”
— Biance Sparacino (How To Ruin Your Life Without Even Noticing That You Are)
The topologist’s sine curve.
Limts: f(x)=sin(1/x) is a rare example of a function with a non-existent one-sided limit. More technically, f(x)=sin(1/x) is defined for all numbers greater than zero, yet the limit as x approaches zero from the right of f(x)=sin(1/x) does not exist. This can be reasoned by considering the value of f at x-values near zero. Informally, f(near zero) could be 1 f(just a bit closer to zero) could be -1 so f(numbers near zero) does not seem to settle on a single y-value.
Continuity: Note that f is continuous for all numbers greater than zero but not continuous at x=0 since f is undefined there. Even if we were to “fill in the bad point” and let f(0)=0, the function would still not be continuous at zero! (note this is the natural choice as sin(0)=0). We can see that the adjusted f is still not continuous at zero since the sequence x_n=1/(pi/2+npi) converges but f(1/x_n) is the sequence (-1)^n which does not converge. This is similar to the argument above. In other words, closing in on x=0, we can keep finding x values such that f(x)=-1 and f(x)=1.
Topology: In topology, the topologist’s sine curve is a classic example of a space that is connected but not path connected. This space is formed in R^2 by taking the graph of f(x)=sin(1/x) together with its limit points (the line segment on the y-axis [-1,1], the red line on the second image). The graph of f is connected to this line segment as f and the segment cannot be sepearted by an open disc (no matter how small). This can be informally reasoned by the zooming illustration in the second image. But the space is not path connected by the sequence argument above (there is no path to the point (0,0)).
Image credits: http://mathworld.wolfram.com/TopologistsSineCurve.html and https://simomaths.wordpress.com/2013/03/10/topology-locally-connected-and-locally-path-connected-spaces/
Unexpected great discoveries. Calculating the cosmos: How mathematics unveils the universe. By Ian Stewart.
being a woman isn’t about the body you were born with or your feelings or your brain it’s about being haunted by this quote from margaret atwood for your entire life
Echoes
I made this painting for the Spellbinders gallery show at @gallerynucleus 💕✨ The opening is on 23rd, if you are in LA then come check it out. I’ll be there signing my new books and also holding a workshop ✨
Small and angry.PhD student. Mathematics. Slow person. Side blog, follow with @talrg.
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