August 23, 2016 | 8:08 Pm | 10/100

01.14.16 4/100 days of productivity

Making study notes for my Abnormal Psychology midterm on Monday~ My hand is cramping 😭

GENERAL SCHOLARSHIP SEARCHES

scholarships.com

Fastweb

SALT

School Soup

CollegeNET

free scholarship search

Scholarship Hunter

collegescholarships.org

Peterson’s

BigFuture

Common Knowledge Scholarship Foundation

INTERNATIONAL STUDENT RESOURCES

EastChance (specifically for eastern european students)

EducationUSA (US government state department website)

International Education Financial Aid (IEFA) 

International Student

eduPASS

STATE-SPECIFIC (by residency, not place of education)

Alaska

Arkansas

California

Iowa

Louisiana

Maine

Missouri

Montana

North Carolina

Oregon

Washington

TIPS AND GUIDES

CollegeBoard: the basics of financial aid

Watching out for scholarship scams

Department of Education student guide

A User’s Guide To The Brain

More about the human brain and behaviour on @tobeagenius

My bullet journal spread this week! ✒️📓

20.3.16// I made a poster on all the organic chemistry reactions we’ve covered so far in the year. It’s a great summary sheet which should be useful come exam time!

5 Things to Probably Never Do on the SAT Essay

Qualifier: Rules are made to be broken, and those below are no exception. Having said that, here are some habits I’d recommend steering clear from on your SAT essay.

1. Probably never use the generic “you.”

Example: “You never know what kind of problems you might get into if you aren’t careful.”

Why this sentence isn’t great: It’s informal, and pretty general.

What to do instead: use “one” in place of “you.” As in, “One never knows what kind of problems one might get into if not careful.” Or, better yet, rewrite the sentence so you to avoid referring to an ambiguous, hypothetical person.

2. Probably never begin an essay with the words “Throughout history…”

Example: “Throughout history, many people have had many different beliefs.”

Why this sentence isn’t great: Again, it’s too general. There isn’t time enough to discuss all recorded history in 25 minutes. So don’t try.

What to do instead: Limit the scope of your argument. Start small, specific. (I’m not going to rewrite the sentence above, as it’d be better to delete it and re-think how to set up the thesis.)

3. Probably avoid generalizations and extreme language.

Example: “Horrible things happen to high school students all the time and they remember those things forever.”

Why this sentence isn’t great: Generalizations like this tend to be either impossible to prove or just plain wrong.

What you can do instead: Qualify your statement, which means to “limit,” “modify” or, as I like to say, “dial it back.”

Rewritten Example: “Certain negative high school experiences are likely to leave a lasting impression.” (Notice how “all” becomes “certain,” I’ve added “likely” and “forever” becomes “lasting impression.”)

A few more words on “qualifying” (because it’s really super important):

We tend to think of “qualifying” as “being eligible” for something. It sometimes mean that, but not here. In this case, I mean taking extreme words and limiting or restricting them. Examples:

Extreme word → Qualified version

“all” → “some” or “certain”

“everyone” → “many people” or better yet, “some people”

“always” → “often,” “in some cases,” “sometimes”

“never” → “rarely” or “seldom”

A few more examples: “My brother is always throwing things at people.” (or) “All men are evil.”

Why these sentences aren’t great: Because these statements aren’t true. And they’re impossible to prove. Read them again and imagine them literally.

Then imagine the evidence you’d need to prove them.

What you can do instead: Qualify ‘em! Dial ‘em back! “My little brother sometimes likes to throw things at people.” (or) “Some argue that all humans have the capacity to do evil.”

*Fun fact: Notice anything about the title of this blog post? #takingmyownadvice

4. Probably never use a hypothetical example.

Example: “When someone says something bad about you it’s like they’re judging you without knowing you.”

What’s not great about this sentence: A few things:

The generic “you.”

It’s general.

It’s a hypothetical example. In other words, it’s not citing something specific that actually happened, so it doesn’t really count as evidence.

What you can do instead: Write about something specific that actually happened. “Last week, when my friend Jac told me that the way I was dressed was “way too preppy,” I felt as if I were being judged.” See how specific?

5. Probably never cite facts without proving them.

Example: “The world is getting more peaceful every day.”

What’s not great about this sentence: Is that true? Can you prove it? How?

What you can do instead: Again, get more specific.

Rewritten example: “Using statistical analysis, psychologist Steven Pinker has argued that the gradual decrease of military conflict, genocide, homicide, torture, and other acts of violence over the last few centuries has led to the present era being the most peaceful time in human history.”

Here’s one more:

Unfounded claim:  “You have to see and hear something to learn about it.”

Rewritten:  “Last year in my AP Psych class we read an article that discussed a study in which some participants received information both visually and aurally while others received the same information only visually or aurally. It turned out that those who received both kinds of information were 20% more likely to retain that information a year later.”

Written by Ethan Sawyer

as i get farther along this academic road, i can see that people are becoming increasingly secretive about their grant proposals, statements for faculty applications, fellowships, etc. what is your policy on sharing these things? i ask because i think you are a Normal Human Being who is a Decent Person, and sometimes this secrecy or tendency to distrust makes me sad!

i understand and i really dislike it as well, but i think it’s important to remember that much of that distrust comes from real and historical patterns of intellectual theft (which hit disproportionately across academia). it’s shitty! the world is a better place when we can share openly and help each other get through the absolute absurdity of the academy! but i can’t think badly of anyone who chooses not to spread their materials around. even though they’re not the same kind of work as, say, a book chapter or an article, we put a lot of labor into documents like proposals and applications, and i think it’s okay to be protective of that labor. 

that said, i’m really open with mine, particularly with people that i actually know. my roommate’s getting a big folder of fellowship and job application materials from me, for example, which is partially bc i love him & the other younger premodernists in my program and want them to succeed, and partially bc i want to save our shared advisor some work. my fellowship group have swapped and given feedback all our job materials, and juliana @caffeinebooks & i exchange proposals all the time. i’m happy to share things like cover letters and research statements with people that i know, because i want to save them some of the angst i went through (which was already ameliorated by the folks who did this for me). it’s harder to muster that kind of generosity towards people i don’t know, because, as selfish as it sounds, i spent 9 hours getting the wording on that cover letter right and i’m enough of an asshole to want to reserve the fruits of that labor for people i know and love, at least until i’ve moved on to other forms of labor. i was not planning on sharing my job materials until i got a job. now i’m cool with it.   

i feel an obligation to pay forward a lot of the help that i’ve gotten on my materials from people who shared theirs with me. but i also understand not being comfortable doing that, or only being comfortable doing that in certain ways. the giving and the getting should be balanced, IMO, but i think it’s up to the individual to decide what that balance looks like for them.

I kind of wish that the idea that you can just be was a little more mainstream.

Like, having drive and ambition is great. But it gets drilled in kids’ heads that there is some pressure to constantly be looking for the next move up, to be bigger than life. It wears you down to never be satisfied.

Not everyone is destined for greatness. It just doesn’t suit some people.

There’s nothing wrong with having a quiet life, making enough to get by, having a small apartment where you’re comfortable, and just living. You don’t have to constantly be looking to go onward and upwards. Sometimes the best thing you can do for yourself is to just be.

This makes me sound stupid but what does a feynman diagram mean?

You don’t sound stupid! They can be pretty confusing at first, and I’m sure you’re not they only one that doesn’t fully understand them (myself included) so let’s learn how to draw Feynman diagrams!

You do not need to know any fancy-schmancy math or physics to do this!

I know a lot of people are intimidated by physics: don’t be! Today there will be no equations, just non-threatening squiggly lines. Even school children can learn how to draw Feynman diagrams. Particle physics: fun for the whole family.

For now, think of this as a game. You’ll need a piece of paper and a pen/pencil. The rules are as follows (read these carefully):

1. You can draw two kinds of lines, a straight line with an arrow or a wiggly line:

You can draw these pointing in any direction.

2. You may only connect these lines if you have two lines with arrows meeting a single wiggly line.

Note that the orientation of the arrows is important! You must have exactly one arrow going into the vertex and exactly one arrow coming out.

3. Your diagram should only contain connected pieces. That is every line must connect to at least one vertex. There shouldn’t be any disconnected part of the diagram.

In the image above, the diagram on the left is allowed while the one on the right is not since the top and bottom parts don’t connect.

4. What’s really important are the endpoints of each line, so we can get rid of excess curves. You should treat each line as a shoelace and pull each line taut to make them nice and neat. They should be as straight as possible. (But the wiggly line stays wiggly!)

That’s it! Those are the rules of the game. Any diagram you can draw that passes these rules is a valid Feynman diagram. We will call this game QED. Take some time now to draw a few diagrams. Beware of a few common pitfalls of diagrams that do not work (can you see why?):

After a while, you might notice a few patterns emerging. For example, you could count the number of external lines (one free end) versus the number of internal lines (both ends attached to a vertex).

How are the number of external lines related to the number of internal lines and vertices?

If I tell you the number of external lines with arrows point inward, can you tell me the number of external lines with arrows pointing outward? Does a similar relation hole for the number of external wiggly lines?

If you keep following the arrowed lines, is it possible to end on some internal vertex?

Did you consider diagrams that contain closed loops? If not, do your answers to the above two questions change?

I won’t answer these questions for you, at least not in this post. Take some time to really play with these diagrams. There’s a lot of intuition you can develop with this “QED” game. After a while, you’ll have a pleasantly silly-looking piece of paper and you’ll be ready to move on to the next discussion:

What does it all mean?

Now we get to some physics. Each line in rule (1) is called a particle. (Aha!) The vertex in rule (2) is called an interaction. The rules above are an outline for a theory of particles and their interactions. We called it QED, which is short for quantum electrodynamics. The lines with arrows are matter particles (“fermions”). The wiggly line is a force particle (“boson”) which, in this case, mediates electromagnetic interactions: it is the photon.

The diagrams tell a story about how a set of particles interact. We read the diagrams from left to right, so if you have up-and-down lines you should shift them a little so they slant in either direction. This left-to-right reading is important since it determines our interpretation of the diagrams. Matter particles with arrows pointing from left to right are electrons. Matter particles with arrows pointing in the other direction are positrons (antimatter!). In fact, you can think about the arrow as pointing in the direction of the flow of electric charge. As a summary, we our particle content is:

(e+ is a positron, e- is an electron, and the gamma is a photon… think of a gamma ray.)

From this we can make a few important remarks:

The interaction with a photon shown above secretly includes information about the conservation of electric charge: for every arrow coming in, there must be an arrow coming out.

But wait: we can also rotate the interaction so that it tells a different story. Here are a few examples of the different ways one can interpret the single interaction (reading from left to right):

These are to be interpreted as: (1) an electron emits a photon and keeps going, (2) a positron absorbs a photon and keeps going, (3) an electron and positron annihilate into a photon, (4) a photon spontaneously “pair produces” an electron and positron.

On the left side of a diagram we have “incoming particles,” these are the particles that are about to crash into each other to do something interesting. For example, at the LHC these ‘incoming particles’ are the quarks and gluons that live inside the accelerated protons. On the right side of a diagram we have “outgoing particles,” these are the things which are detected after an interesting interaction.

For the theory above, we can imagine an electron/positron collider like the the old LEP and SLAC facilities. In these experiments an electron and positron collide and the resulting outgoing particles are detected. In our simple QED theory, what kinds of “experimental signatures” (outgoing particle configurations) could they measure? (e.g. is it possible to have a signature of a single electron with two positrons? Are there constraints on how many photons come out?)

So we see that the external lines correspond to incoming or outgoing particles. What about the internal lines? These represent virtual particles that are never directly observed. They are created quantum mechanically and disappear quantum mechanically, serving only the purpose of allowing a given set of interactions to occur to allow the incoming particles to turn into the outgoing particles. We’ll have a lot to say about these guys in future posts. Here’s an example where we have a virtual photon mediating the interaction between an electron and a positron.

In the first diagram the electron and positron annihilate into a photon which then produces another electron-positron pair. In the second diagram an electron tosses a photon to a nearby positron (without ever touching the positron). This all meshes with the idea that force particles are just weird quantum objects which mediate forces. However, our theory treats force and matter particles on equal footing. We could draw diagrams where there are photons in the external state and electrons are virtual:

This is a process where light (the photon) and an electron bounce off each other and is called Compton scattering. Note, by the way, that I didn’t bother to slant the vertical virtual particle in the second diagram. This is because it doesn’t matter whether we interpret it as a virtual electron or a virtual positron: we can either say (1) that the electron emits a photon and then scatters off of the incoming photon, or (2) we can say that the incoming photon pair produced with the resulting positron annihilating with the electron to form an outgoing photon:

Anyway, this is the basic idea of Feynman diagrams. They allow us to write down what interactions are possible. However, you will eventually discover that there is a much more mathematical interpretation of these diagrams that produces the mathematical expressions that predict the probability of these interactions to occur, and so there is actually some rather complicated mathematics “under the hood.” But just like a work of art, it’s perfectly acceptable to appreciate these diagrams at face value as diagrams of particle interactions.  Let me close with a quick “frequently asked questions”:

What is the significance of the x and y axes?These are really spacetime diagrams that outline the “trajectory” of particles. By reading these diagrams from left to right, we interpret the x axis as time. You can think of each vertical slice as a moment in time. The y axis is roughly the space direction.

So are you telling me that the particles travel in straight lines?No, but it’s easy to mistakenly believe this if you take the diagrams too seriously. The path that particles take through actual space is determined not only by the interactions (which are captured by Feynman diagrams), but the kinematics (which is not). For example, one would still have to impose things like momentum and energy conservation. The point of the Feynman diagram is to understand the interactions along a particle’s path, not the actual trajectory of the particle in space.

Does this mean that positrons are just electrons moving backwards in time?In the early days of quantum electrodynamics this seemed to be an idea that people liked to say once in a while because it sounds neat. Diagrammatically (and in some sense mathematically) one can take this interpretation, but it doesn’t really buy you anything. Among other more technical reasons, this viewpoint is rather counterproductive because the mathematical framework of quantum field theory is built upon the idea of causality.

What does it mean that a set of incoming particles and outgoing particles can have multiple diagrams?In the examples above of two-to-two scattering I showed two different diagrams that take the in-state and produce the required out-state. In fact, there are an infinite set of such diagrams. (Can you draw a few more?) Quantum mechanically, one has to sum over all the different ways to get from the in state to the out state. This should sound familiar: it’s just the usual sum over paths in the double slit experiment that we discussed before. We’ll have plenty more to say about this, but the idea is that one has to add the mathematical expressions associated with each diagram just like we had to sum numbers associated with each path in the double slit experiment.

What is the significance of rules 3 and 4?Rule 3 says that we’re only going to care about one particular chain of interactions. We don’t care about additional particles which don’t interact or additional independent chains of interactions. Rule 4 just makes the diagrams easier to read. Occasionally we’ll have to draw curvy lines or even lines that “slide under” other lines.

Where do the rules come from?The rules that we gave above (called Feynman rules) are essentially the definition of a theory of particle physics. More completely, the rules should also include a few numbers associated with the parameters of the theory (e.g. the masses of the particles, how strongly they couple), but we won’t worry about these. Graduate students in particle physics spent much of their first year learning how to carefully extract the diagrammatic rules from mathematical expressions (and then how to use the diagrams to do more math), but the physical content of the theory is most intuitively understood by looking at the diagrams directly and ignoring the math. If you’re really curious, the expression from which one obtains the rules looks something like this (from TD Gutierrez), though that’s a deliberately “scary-looking” formulation.

You’ll develop more intuition about these diagrams and eventually get to some LHC physics, but hopefully this will get the ball rolling for you.

heLLO!! this post includes really cool stuff just like u (;

*beauty guru voice* “lets just dive right in” 

time management

Hex Clock: This is literally the COOLEST THING EVER. im not good at describing things either but giving this one a shot. so basically its 21.56PM right now. its shows #215602 (hour, minute, second) and the background is that hex codes coLOR. cool am i right ladies ;)

Timer-Tab: This is extremely useful! It has a countdown thingy and when it ends it pops up a video from YouTube, guess what it is. Guess it. ITS A ANTIQUE CLOCK ALARM!! You can change it too! And the background! Aaand it has a stopwatch too! Quick hack: put fullcreen after the hashtag on the url. ;)

note taking

ZenPen: It gives you two background options and unlimited options to edit your text.

Escriba: Super simple and super easy to use.

educational

UReddit: UReddit hosts courses and lessons created by the public and can help users to learn languages, scientific principles or even PHP programming.

edX: “Best Courses. Top Institutions. Learn anytime, anywhere.” You have to check this site out.

money saving

Mint: Free to use, Mint can help you organize your finances and track your spending

Wise Bread: WiseBread is dedicated to living well on a tight budget – whether you’re a student or just trying to get more for your money. It offers advice on everything from debt management to growing your own fruit and vegetables.

RetailMeNot(us only): I feel your pain if you’re not in the USA.But I don’t if you’re in the UK because there’s a UK version of it;

MyVouchers(uk only): They both offer discounts for retail stores & restaurants.

random

Sleepyti.me: This site tells you the best times to go to bed if you have to be up at a certain hour

KeepMeOut!: Gives you warnings when you’re on a website(social media) when you’re meant to be studying.

MentalFloss: Hits you with that random fact. Did you know?  Michael Jackson wanted to do a Harry Potter musical. J.K. Rowling said no. BOOM!

ToDoist: Your classic to do list. But more clean and on a screen.

other masterposts:

youtube channels about science

online stationery shops

resources: x,x