What is the newest installment of 'Random Thoughts' on Physics Forums?

[nuuskur]

Took my topology qualifier. I know for sure it wasn't a disaster, but not for sure whether I got a master's pass. I keep going over it in my head... But I literally can't' remember a thing about it other than I answered a bunch of questions. Sometimes I felt more as if I was giving my opinion than showing a mathematical proof, but at least it was an *informed* opinion. :D

uh oh.. I have been working on trying NOT to give opinion, but concise proof, instead :D
I think as long as you aren't discussing horse keeping principles on a topology test, you're fine haha

reminds me of my first algebra test in uni, I was so lost, I drew pictures of a giant equation eating the professor [don't ask what it means, I don't know].

 

[fresh_42]

Took my topology qualifier. I know for sure it wasn't a disaster, but not for sure whether I got a master's pass. I keep going over it in my head... But I literally can't' remember a thing about it other than I answered a bunch of questions. Sometimes I felt more as if I was giving my opinion than showing a mathematical proof, but at least it was an *informed* opinion. :D

I think that's normal and likely a sign for good answers. I remember a student in an undergraduate exam who has been asked what a linear mapping is. She answered by all defining properties, and the follow-up questions was about "the nature" of linear mappings and to give an example. I guess she doesn't know until today, why she only got a "C". Bad students don't ask themselves the kind of questions that bother you.

 

[nuuskur]

I think that's normal and likely a sign for good answers. I remember a student in an undergraduate exam who has been asked what a linear mapping is. She answered by all defining properties, and the follow-up questions was about "the nature" of linear mappings and to give an example. I guess she doesn't know until today, why she only got a "C". Bad students don't ask themselves the kind of questions that bother you.

I wouldn't like such a question. So much ambiguity. What do you mean by "its nature"? I can name plenty of different properties of linear maps do they constitute as descriptions for the nature of linear maps?

 

[fresh_42]

I wouldn't like such a question. So much ambiguity. What do you mean by "its nature"? I can name plenty of different properties of linear maps do they constitute as descriptions for the nature of linear maps?

Well, it's one thing to quote properties like $L(x+y)=L(x)+L(y)$, but a completely different one to understand why this is required, i.e. what a linear mapping means. And if you are asked for an example and don't know any, then I'd say the knowledge of the definition is worth nothing.

 

[dkotschessaa]

I think that's normal and likely a sign for good answers. I remember a student in an undergraduate exam who has been asked what a linear mapping is. She answered by all defining properties, and the follow-up questions was about "the nature" of linear mappings and to give an example. I guess she doesn't know until today, why she only got a "C". Bad students don't ask themselves the kind of questions that bother you.

One thing at least I have gotten over as a graduate student, and perhaps just as an adult, is not caring whether I look stupid or not. I used to avoid answering questions just because I thought it probably wasn't right and I was embarrassed about it. Now I at least write something down if I have an idea about it. "Here is my understanding."

-Dave K

 

[dkotschessaa]

Well, it's one thing to quote properties like $L(x+y)=L(x)+L(y)$, but a completely different one to understand why this is required, i.e. what a linear mapping means. And if you are asked for an example and don't know any, then I'd say the knowledge of the definition is worth nothing.

I would have to see the question in question :D. But Munkres actually says something about what he calls "open ended" questions in his book. Sometimes they are the most enlightening and most frustrating types of questions. They also are the type that mathematicians are likely to be faced with initially in research. They only get boiled down to rigorous definitions after much effort.

Probably a whole thread topic could be had on this.

-Dave K

 

[fresh_42]

I would have to see the question in question

It was a verbal exam, i.e. the entire exam was a dialog. The crucial point here is, and I think it is one of the most important things to learn, not to say the most important thing, that you could know an entire textbook and still don't have an idea what it is about. It's the difference between a machine and a human being. It has been the kind of professors who tested understanding first, knowledge second.

 

[dkotschessaa]

It was a verbal exam, i.e. the entire exam was a dialog. The crucial point here is, and I think it is one of the most important things to learn, not to say the most important thing, that you could know an entire textbook and still don't have an idea what it is about. It's the difference between a machine and a human being. It has been the kind of professors who tested understanding first, knowledge second.

Oh wow, I've never witnessed a verbal exam in mathematics! (Other than watching a dissertation defense.)

I totally agree with you though. I've noticed that some undergraduates in particular are very good at "gaming" the system. They know how to answer, what to answer, when to answer on tests. They have lawyer-like skills for negotiating what should be on a test and what shouldn't be, or why a question wasn't fair. They know how to get good grades. But their knowledge of the material? Meh.

-Dave K

 

[fresh_42]

Oh wow, I've never witnessed a verbal exam in mathematics!

I had to write the protocol. I first thought I could beat the record on the most exams, but the guy who was the record holder had more than 500. So I decided to set a record on "number of professors". I ended up with about a dozen different profs, which was a great experience that taught me many insights on interviews. The chances are high, that I'm still the record holder. I even manged to protocol all exams of a single student. He told me afterwards that he's tired to see me, although he was an all "A" student.

 

[OmCheeto]

You should see what Hollywood makes out of non-American history ...

Researching stuff for mother's day yesterday, I ran across the following:

October 26, 1948
Landed in Bermenhaven yesterday and rode the train to Marburg last night.
This is a beautiful country here. The barracks we’re living in here used o be the headquarters for Adolfs’ S.S. troops.
There are still bullet holes in the walls from when the Krauts got run out.
I’ll write again. Till then, So Long.

My mom was born somewhere near 50° 53′ 20″ N, 15° 59′ 59″ E.
About 16 years later, she would be in the Luftwaffe.
My dad eventually ended up in the American Luftwaffe, but not until after my oldest brother was born in Aschaffenburg.
My other older brother was born in Frankfurt.

Und das is vhy itch kanst very goot doych sprecken.

[edit: Dad would have been 19 years old when he wrote that letter]

 

[WWGD]

It was a verbal exam, i.e. the entire exam was a dialog. The crucial point here is, and I think it is one of the most important things to learn, not to say the most important thing, that you could know an entire textbook and still don't have an idea what it is about. It's the difference between a machine and a human being. It has been the kind of professors who tested understanding first, knowledge second.

Yes, this is much easier in an Oral exam, pretty hard in a written one.

 

[fresh_42]

My dad eventually ended up in the American Luftwaffe, but not until after my oldest brother was born in Aschaffenburg.
My other older brother was born in Frankfurt.

This is creepy! Guess where my two nephews have been born! Should my sister hide a giant family secret? I know they first lived in OR or WA (can't remember) as they moved to the US ...

 

[OmCheeto]

This is creepy! Guess where my two nephews have been born! Should my sister hide a giant family secret? I know they first lived in OR or WA (can't remember) as they moved to the US ...

Secrets! That would make a good thread.

Actual conversation I had on May 5, 2017:

Preface: Om's sister posts picture of oldish looking submarine, asking me if I recognized it.

Om; "Где вы нашли эту лодку?" [=Where did you find this boat?]

Om; "Slava bogu[thank god] dads sister claimed we were Germans from Russia. Otherwise I'd have learned Ukrainian. ps. My Russian friends claim that everyone in the Ukraine speaks Russian, even if they pretend they don't. Which has been my experience."

Om's sister, born in Florida; "No, we were German that went to Russia to teach farming~"

Om; "Keep telling yourself that. I have a Russian friend who spent lots of time in the Odessa oblast. She claims the first time she saw me that she told her husband I looked Ukrainian. I had to laugh when she told me that. It would appear that great great grandma got more than milk from the milk man. :D"​

ps. It is a Russian submarine in Hamburg.

 

[dkotschessaa]

I had to write the protocol. I first thought I could beat the record on the most exams, but the guy who was the record holder had more than 500.

Sorry, 500 what?

 

[fresh_42]

Sorry, 500 what?

Exams in which he was the one to write the protocol; I think I made it to the second half of the two hundreds.

 

[dkotschessaa]

exams in which he was the one to write the protocol

Oh dear! Speaking of human vs. machine...

 

[zoobyshoe]

I wonder who the first person was who had the idea to try and eat a crab. They must have been really hungry.

 

[dkotschessaa]

I wonder who the first person was who had the idea to try and eat a crab. They must have been really hungry.

They probably drank from a coconut too. I think the effort to get at the nutrition cancels out any caloric intake.

 

[fresh_42]

From one omnivore to the other ...

They probably drank from a coconut too. I think the effort to get at the nutrition cancels out any caloric intake.

Unlikely. The settlement of the Americas took place along the coast lines and it's very likely, that it had to do with the presence of food from the pacific. O.k. the American ice shield has probably also played a role. Even a group in the population of Japanese macaques has learned to eat "sea food" in order to survive in winter. And consider the efforts sea otters undertake to crack sea shells! My bet would be, that we first threw them into a fire. And imagine the trouble early humans had to get to nutritious marrow. As long as we can crack it ...

 

[zoobyshoe]

What I meant was crabs are scary-looking, like large spiders. A person would have to be really hungry to start wondering if crabs might be edible.

 

[dkotschessaa]

What I meant was crabs are scary-looking, like large spiders. A person would have to be really hungry to start wondering if crabs might be edible.

Perhaps you and @fresh_42 are onto something then. Someone was sleeping by the fire, felt something crawling on their face. When they woke up, it was a crab. They grabbed it and threw it into the fire. It smelled delicious.

-Dave K

 

[zoobyshoe]

Perhaps you and @fresh_42 are onto something then. Someone was sleeping by the fire, felt something crawling on their face. When they woke up, it was a crab. They grabbed it and threw it into the fire. It smelled delicious.

This is certainly exactly how it happened. I'm pretty sure we can just write that scenario into the history books as gospel truth.

 

[dkotschessaa]

This is certainly exactly how it happened. I'm pretty sure we can just write that scenario into the history books as gospel truth.

The name "crab" of course derives from the utterance made by this person (his name was Og) when the incident occurred. 'CRAAAAAABB!'.

Interesting trivia: Og's grandfather, Ahh!, was the one who actually invented fire, sometimes considered the world's first scientist. (Of course that is why we say "Ahh!" when we burn ourselves.)

-Dave K

 

[zoobyshoe]

The name "crab" of course derives from the utterance made by this person (his name was Og) when the incident occurred. 'CRAAAAAABB!'.

Interesting trivia: Og's grandfather, Ahh!, was the one who actually invented fire, sometimes considered the world's first scientist. (Of course that is why we say "Ahh!" when we burn ourselves.)

Yes, this has to be the way it happened! My God, it's like you were there!

 

[WWGD]

My Android spell-checked Starbucks. Will it spell-check any commercial name? Does it keep tyrack of them, I guess learns as I text?

 

[collinsmark]

My Android spell-checked Starbucks. Will it spell-check any commercial name?

I think it depends on the lexicon being used.

Android has a built in spelling checker framework that your app might be using, or it might use its own, custom spell checker. Which commercial names are within its lexicon by default depends on which spelling checker your app is using, and which language -- ultimately which lexicon you are using.

Does it keep tyrack of them, I guess learns as I text?

If I'm not mistaken, if the app is using the built-in android framework, it will ask you if you want to add suspect words to the "dictionary" (what it calls the lexicon).

Of course, the problem is that if you accidentally add a misspelled word to your lexicon, it will fail to flag that word as misspelled in the future.

 

[jim hardy]

What I meant was crabs are scary-looking, like large spiders. A person would have to be really hungry to start wondering if crabs might be edible.

My guess is kids watched otters enjoying them.

and observed if you grab them from behind their pincers can't reach you.

 

[dkotschessaa]

I think it depends on the lexicon being used.

Android has a built in spelling checker framework that your app might be using, or it might use its own, custom spell checker. Which commercial names are within its lexicon by default depends on which spelling checker your app is using, and which language -- ultimately which lexicon you are using.
If I'm not mistaken, if the app is using the built-in android framework, it will ask you if you want to add suspect words to the "dictionary" (what it calls the lexicon).

Of course, the problem is that if you accidentally add a misspelled word to your lexicon, it will fail to flag that word as misspelled in the future.

And is it just me or does it look like other people's misspellings are starting to work their way in? I get some very strange auto-correct suggestions sometimes that I know did not come from me. It seems eventually it will negate the entire process.

-Dave K

 

[zoobyshoe]

My guess is kids watched otters enjoying them.

That makes sense. Even I would assume that if an otter can eat something there's a high likelihood a human could too.

 

[fresh_42]

That makes sense. Even I would assume that if an otter can eat something there's a high likelihood a human could too.

Or even simpler than that: it moves → it moves slowly enough to easily be caught → no plant → no poisonous plant → hmmm, delicious. I assume people hadn't much of a choice at the time we first ate it.