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## #1 2014-12-02 04:32:19

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### What had you learned today that you found interesting?

Tell us what you had learnt today.

Last edited by David (2014-12-02 05:14:14)

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #2 2014-12-02 05:30:15

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### Re: What had you learned today that you found interesting?

3rd December 2014
#1 I learned that owning a cat will reduce the likeliness of getting a stroke of a heart attack by a third. But I'm allergic to cats!

#2 There is no pain receptors in the brain.

Last edited by David (2014-12-02 05:34:36)

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #3 2014-12-02 06:41:24

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,045

### Re: What had you learned today that you found interesting?

Today I learned that you can very effectively use linear algebra to solve some combinatorics problems.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #4 2014-12-02 09:26:13

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

### Re: What had you learned today that you found interesting?

I learned about the collisionless Boltzmann equation and baryon asymmetry today (well, not for the first time, but more in detail).

Last edited by ShivamS (2014-12-02 09:27:01)

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## #5 2014-12-03 00:33:07

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### Re: What had you learned today that you found interesting?

Carrots are orange in colour because of beta-carotene. Beta-carotene is a precursor of vitamin A.

Last edited by David (2014-12-03 00:33:57)

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #6 2014-12-03 01:02:42

danaj
Member
Registered: 2014-03-03
Posts: 29

### Re: What had you learned today that you found interesting?

http://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=26247

and

http://arxiv.org/abs/1409.1780

Improvements to the Dusart (2010) bounds on prime count and nth prime.  I also started playing around with nth prime limits via binary search on prime count bounds, which tentatively looks like a nice improvement (indicating that the prime count bound formulas are tighter than the nth prime bound formulas).

Also, someone finished computation of Pi(10^26) via combinatorial methods.

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## #7 2014-12-03 02:21:33

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,912
Website

### Re: What had you learned today that you found interesting?

Today I learnt about the Landaur's Principle

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #8 2014-12-03 03:24:55

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: What had you learned today that you found interesting?

Learned another easier way to deal with an ergodic process.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #9 2014-12-04 03:31:07

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### Re: What had you learned today that you found interesting?

I learned how to deal with Pertussis patients.

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #10 2014-12-04 07:45:00

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

### Re: What had you learned today that you found interesting?

I learned a significant amount of things about Wilson loops today.

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## #11 2014-12-05 01:32:05

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### Re: What had you learned today that you found interesting?

Interesting, ShivamS. I will try a find time to read about it.

I found a way to remember pi.

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #12 2014-12-05 01:34:34

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: What had you learned today that you found interesting?

I just learned something new about polynomials.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #13 2014-12-05 13:23:51

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,045

### Re: What had you learned today that you found interesting?

I've learned that there is a very interesting and somewhat natural measure of graph connectedness which also has some nice algebraic properties.

Also, I'm looking to better myself in the study of non-standard analysis, so I've been learning about that a bit too.

Last edited by anonimnystefy (2014-12-05 13:24:04)

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #14 2014-12-06 01:38:28

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,146

### Re: What had you learned today that you found interesting?

Listen! The Lord’s arm is not too weak to save you, nor is his ear too deaf to hear you call. (Isaiah 59:1).
For whosoever shall call upon the name of the Lord shall be saved. (Romans 10:13).

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## #15 2014-12-12 07:25:45

Olinguito
Member
Registered: 2014-08-12
Posts: 649

### Re: What had you learned today that you found interesting?

I learn that it is possible to make a tetradecahedron with just regular hexagons and squares.

Bassaricyon neblina

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## #16 2015-07-26 09:56:42

Nehushtan
Member
Registered: 2013-03-09
Posts: 957

### Re: What had you learned today that you found interesting?

Today I learn that the golden ratio has the following interesting property:

[list=*]
[*]

[/*]
[/list]

http://mathhelpforum.com/algebra/246829-expression.html#post864349

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## #17 2015-07-26 19:56:24

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: What had you learned today that you found interesting?

I have learned that if a = b and b = c then it follows that a = c.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #18 2015-07-27 00:47:34

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,912
Website

### Re: What had you learned today that you found interesting?

Oh?

I learned that I am 14

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #19 2015-07-27 07:00:31

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: What had you learned today that you found interesting?

I learned about a route to the haunted lake. It is almost unknown to the residents around here. All that remains is the gear and the courage to go.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #20 2016-01-02 06:05:39

Nehushtan
Member
Registered: 2013-03-09
Posts: 957

### Re: What had you learned today that you found interesting?

Yesterday I learned that lysosomes can digest mitochondria, ribosomes, peroxisomes, glycogen granules and other intracellular structures. I was reading about degradation of internally produced material in the section on lysosome function in the chapter on lysosomes of a book about biochemistry and structure of cell organelles. Autophagy is when this happens to an apparently healthy organelle.

Last edited by Nehushtan (2016-01-02 06:06:13)

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## #21 2016-01-17 02:50:34

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,912
Website

### Re: What had you learned today that you found interesting?

I learnt the Revelation Principle

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #22 2016-01-17 04:05:11

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: What had you learned today that you found interesting?

I learned how to solve a new type combinatorics problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #23 2016-02-17 16:49:50

Newman
Member
Registered: 2015-09-21
Posts: 42

### Re: What had you learned today that you found interesting?

I learned that they've gone out 10^14 and haven't found integers where a^3 + b^3 + c^3 = 33

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## #24 2016-02-17 16:55:44

Newman
Member
Registered: 2015-09-21
Posts: 42

### Re: What had you learned today that you found interesting?

...and magic hexagon and unit circle. And started learning about I matrix vs 0 matrix. I actually learned (relearned) a heckload of math today. Haha! Now, I just have to practice it for 1000 hours so as not to forget.

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## #25 2016-02-17 19:12:21

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 2,000

### Re: What had you learned today that you found interesting?

I learnt that the Arabic word for "rain" is "maTr", which sounds like "motor".

Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.

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