Today I Learned

[Jonathan Scott]

Point us toward said paper ? I like "Newtonian concepts" and need "easily understandable".

Here's my thread on the subject: Reference for coordinate view of equations of motion

 

[OmCheeto]

Point us toward said paper ? I like "Newtonian concepts" and need "easily understandable".

It involves one of those "upside down mathematical triangle" thingys so I'm going to have to exclude myself from THAT conversation. It has been my personal experience that when they show up nothing is easily understandable. I learned that long ago so I do believe I'm off topic. Ergo as always ok to delete infract and ban. ps. One of my literate friends says I use way too many commas when I write things so you can blame him if this post seems a bit odd. pps. I've decided that I also use double spacing as an implied verbal pause so I've taken those out also.

 

[Jonathan Scott]

It involves one of those "upside down mathematical triangle" thingys so I'm going to have to exclude myself from THAT conversation.

Yup, $\nabla$ is the "nabla" symbol, usually read as "del" in this context, and it just means "gradient of" in this context. That's just how the Newtonian gravitational field $g$ is defined, in terms of the gradient of the potential.

 

[jim hardy]

One of my literate friends says I use way too many commas when I write things so you can blame him if this post seems a bit odd. pps. I've decided that I also use double spacing as an implied verbal pause so I've taken those out also.

I do too. I think in my case it stems from my scrambledness, my whole life is one disjointed run-on sentence.
I use the excuse i read Moby Dick in 2nd grade when just learning to read well, and i still remember Melville's whole page long sentences.
So i always go back over my writing, replace commas with carriage returns and chop it up into one thought per line.

The double spaces have crept in the last few years, they're like a pause when speaking. My;;;;;;;' s mean "Uhhhh."

But i consider it "A Fine Madness" .
http://www.imdb.com/title/tt0060414/

old jim

 

[BillTre]

One of my literate friends says I use way too many commas when I write things so you can blame him if this post seems a bit odd. pps. I've decided that I also use double spacing as an implied verbal pause so I've taken those out also.

My Dad did a lot of writing. The major piece of advice I picked up from him was "keep your sentences short and simple".
Take big sentences and make them into multiple little ones.
I also use parentheses instead of commas a lot (for parenthetical thoughts). They set things off well visually and avoid the confusing comma rules.

Rather than thinking of extra vertical space as a verbal pause, I think of them as a visual layout device.
The extra space sets the next thoughts apart visually, while single spaces group them visually.
Indenting works well for sub-grouping.

 

[Jonathan Scott]

Today my wife and I learned that our "usual" baking tray for the turkey can't really be our "usual" baking tray - because it doesn't fit in the oven. Perhaps it was for our previous cooker, but that must have been at least 10 years ago, probably a lot more! Fortunately, we had another one stashed away which fitted.

 

[BillTre]

Opps. The indenting on this line was not maintained after posting:

Indenting works well for sub-grouping.

 

[mfb]

Use [indent]bla[/indent]. Whitespace at the start of a line gets ignored by browsers.

 

[BillTre]

Use [indent]bla[/indent]. Whitespace at the start of a line gets ignored by browsers.

Good to know.
Thanks @mfb!

 

[1oldman2]

T.I.L. that my wife won't let me choose next years Christmas tree, this year I chose a Tamarack.

 

[fresh_42]

T.I.L. that my wife won't let me choose next years Christmas tree, this year I chose a Tamarack.

Yep, happens without definitions ... I suppose to offer the usage of PF's homework template wouldn't be a good idea either.
Yesterday I've read: "My wife is like the bible. Whether translation and interpretation is correct cannot always be said. But her word is law."

 

[jim hardy]

"My wife is like the bible. Whether translation and interpretation is correct cannot always be said. But her word is law."

Lots of wisdom in that. It's not important who decides little things, only that nobody feels trod upon. It's healthy to indulge a good partner.

I get a lot of mileage out of "That's a Big Ten-YesDear , Good Buddy" .

 

[1oldman2]

I get a lot of mileage out of "That's a Big Ten-YesDear , Good Buddy" .

It's the little things like that that have such a huge bearing on a relationship, the divorce rate would be cut by half if people only grasped that concept before planning on spending the rest of their lives together. My wife says marriage is like a job, you go to work each day and give it your best and there's no need to worry about getting canned. (this isn't something I "learned today" but it's worth mentioning in this thread if only one couple gets the gist of it)

 

[Jonathan Scott]

Today I learned that it's not a good idea to step onto a sloping footpath which is covered in black ice. I landed heavily on my chest and chin (which luckily was partly protected from scraping by my beard).

Fortunately, the footpath in question was in a hospital car park (as I was departing towards my wife's car after an appointment for physiotherapy on a sore shoulder), and when I staggered into reception they immediately rushed into action ... to lay grit on the paths.

They were actually quite helpful and sympathetic, and once I'd recovered from the immediate shock and being winded they had a doctor check me out. Just some superficial grazes on the outside, and no sign of broken bones, although my chest is very uncomfortable, especially when I laugh or hiccup, and I'm having to eat very slowly because of jaw ache.

 

[fresh_42]

... Fortunately, the footpath in question was in a hospital car park (as I was departing towards my wife's car after an appointment for physiotherapy on a sore shoulder), and when I staggered into reception they immediately rushed into action ... to lay grit on the paths. ...

Unfortunately for you this happened in the wrong country ...
My best wishes!

 

[dkotschessaa]

Today I learned that it's not a good idea to step onto a sloping footpath which is covered in black ice. I landed heavily on my chest and chin (which luckily was partly protected from scraping by my beard).

Today I learned that beards make decent face armor.

 

[1oldman2]

when I staggered into reception they immediately rushed into action ... to lay grit on the paths.

In the US this action would have been accomplished by simultaneously contacting the hospitals legal dept. and going into "damage control" mode. Here it's customary to sue first, details later. I assume that like myself, these adventures aren't as much "fun" for you as they were when you were twenty, hope your feeling better soon.

 

[1oldman2]

Today I learned that beards make decent face armor.

This is true as most people wearing a beard will attest, (although most armor isn't nearly so flammable )

 

[zoobyshoe]

This is true as most people wearing a beard will arrest...

Hmmm, no. Law enforcement officers are actually mostly clean shaven.

 

[1oldman2]

Hmmm, no. Law enforcement officers are actually mostly clean shaven.

Thank you for that correction, spellcheck won't save my butt in a case like this.

 

[dkotschessaa]

Thank you for that correction, spellcheck won't save my butt in a case like this.

Can't slip anything past the Zoob.

 

[levadny]

:)

Today I learn Java and Algoritmic toolbox in Coursera.

Anybody learn Russian language?

 

[1oldman2]

Anybody learn Russian language?

Not me, but my cousin is quite fluent. (Compliments of the USAF)

 

[Aufbauwerk 2045]

:)

Today I learn Java and Algoritmic toolbox in Coursera.

Anybody learn Russian language?

I study Russian when I have time, which is not often. I want to learn to read scientific Russian so I can understand Priroda and other journals.

 

[zoobyshoe]

Today I learned that the world's largest recorded iceberg, Iceberg B-15, was as large as the state of Connecticut.

 

[levadny]

I can help to learn Russian in Skype for example. One time in week. Twenty or more minutes. Russian instead of English or other language if you want.
Please write if this property interests you.

 

[dkotschessaa]

So as part of Project Supernerd (i.e. raising my son) I have been compiling some playlists for my 11 month old, including this one of classical music written for children. (Some of them are actually songs that his bedside crib machine thingy was playing, so I put those on the list).

Anyway, included in this is Mozart's 12 variations of Twinkle, Twinkle, Little Star.

It is a running joke that my wife refuses to acknowledge the fact that this is the same melody used as the alphabet song (in English anyway), a fact which took me over 30 years to even realize.

But now I realize that my ignorance is even greater! The song is actually "Ah! vous dirai-je, maman," (translating apparently to "Oh! Shall I tell you, Mommy") a French children's song.

Thus when we sing the alphabet song we are not simply using "Twinkle" as a mnemonic device but a much older melody which is also used in "Baa, baa, Black Sheep" and "https://en.wikipedia.org/w/index.php?title=Morgen_kommt_der_Weihnachtsmann&action=edit&redlink=1 " (German for "Santa Claus is coming tomorrow")

Mind blown?!

I know this is why you come to physics forums.

-Dave K

 

[fresh_42]

So as part of Project Supernerd (i.e. raising my son) I have been compiling some playlists for my 11 month old, including this one of classical music written for children...

Wow, Prokofiev, Tchaikovsky, Chopin ... you give it to him the hard way, don't you? At least you stayed away from Wagner ... And Frère Jacques could be nice to add.

 

[dkotschessaa]

Wow, Prokofiev, Tchaikovsky, Chopin ... you give it to him the hard way, don't you?

ha. When you put it that way it sounds bad, but they are pieces written (supposedly) for children.

He gets the easy kids stuff to, also plenty of rock music and Spanish music (Salsa especially) and I occasionally subject him to jazz.

At least you stayed away from Wagner ...

I actually really like Parsifal but I won't subject him to it against his will. At least not yet...

And Frère Jacques could be nice to add.

I've generally regarded this as a nursery rhyme, but according to Wikipedia "Frère Jacques bears resemblance to the piece Toccate d'intavolatura, No.14, Capriccio Fra Jacopino sopra L'Aria Di Ruggiero composed by Girolamo Frescobaldi,[15] " So I might look that up.

We sing it to him in a couple of variations. I sometimes sing it in English as "brother john" and sometimes I try it in (probably very bad) French.

My wife does a little finger game "Where is pointer? Where is Pointer? Here I am! Here I am!" to the melody.

Needless to say I am learning a lot from my son, though it's not the kind of stuff I realized I'd be learning at this age.

-Dave K

 

[Jonathan Scott]

Thus when we sing the alphabet song we are not simply using "Twinkle" as a mnemonic device but a much older melody which is also used in "Baa, baa, Black Sheep" and "https://en.wikipedia.org/w/index.php?title=Morgen_kommt_der_Weihnachtsmann&action=edit&redlink=1 " (German for "Santa Claus is coming tomorrow")
-Dave K

There were at least two previous melodies used for Twinkle Twinkle Little Star before it mostly migrated to the current one.
One of them is shown in the Wikipedia article: https://en.wikipedia.org/wiki/Twinkle,_Twinkle,_Little_Star
I have another one (which I particularly like) in an old song book "What the Children Sing" from 1915, which I used to sing to my own children. I've just found the relevant page online:
http://www.traditionalmusic.co.uk/what-children-sing/what-children-sing - 0142.htm
I also use a different alphabet song which my mother taught me, which avoids the garbled "LMNOP" for the "Twinkle" version, but I can't find it online.