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Iulian Dumitraşcu
4,563 followers -
communication & collaboration services
communication & collaboration services

4,563 followers
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To start a Hangout with any of most Google Plus users:
1. Go to the their profile page and copy their numerical profile ID (the last part of the profile's Web address) from the URL field of that browser page.
If you see an alphabetical ID in this field, go to the user's first post, open the context menu of their name, and press "Copy link address".
2. Press the following incomplete address:
https://hangouts.google.com/?action=chat&pi=
3. Paste the user's numerical ID at the end of this address.
4. Go to the address you have just created.
You can write a person if you are in a (sometimes very large) group to whom they allow it. Much less than half of the people you address seem to reply.
Up to 150 people can write in a Hangout, up to 25 people can talk in a Hangout (On Air).
You can name Hangouts. You must name Hangouts On Air.
You can ask Google to assign a Web address to a group Hangout. Google assigns a Web address to each call placed as a Hangout or a Hangout On Air.
You can start a Hangout with me here:
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In the film "Toto a colori", Antonio de Curtis says: "Per la colpa tua, prima abbiamo perduto la guerra, adesso abbiamo perduto la pace."
In short: We lost the war, then the peace, i.e. our peace.
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I'm looking for people with whom I'd live such sunrises. This one was more beautiful than we can see in this picture.
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Care aţi achitat o factură Google ca persoană juridică română neînregistrată pentru TVA?
Dacă factura nu era de la Google, era de la o persoană juridică înregistrată în UE pentru TVA şi era pentru servicii cărora mi se pare că le spun "electronice"? Întreb pentru că pentru acestea ţara prestaţiei este ţara beneficiarului.
Vreau să îmi abonez societatea la G Suite şi Google spune că nu facturează TVA. Am încercat să aflu de exemplu din directiva 112/CE din 2006 şi din codul nostru fiscal dacă trebuie să plătim TVA şi n-am reuşit. Care mă ajutaţi şi cum să vă răsplătesc?
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We have inherited many such ways to let beings interact in relation to our farming. Do you see any reason reason to poison anybody?
At a South African vineyard, every day is Take Your Duck to Work Day!
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Iulian Dumitraşcu commented on a post on Blogger.
I don't seem able to go live from my Nexus 6P on Android in Romania.
No country list is included in this article; does this mean than this service should be available in all countries?
What conditions does one have to meet to use this service? I hope none, because I keep advertising your services including to facebook users. (A condition I accept is to pay for your services, which I already do.)
For instance, what is the minimum number of subscribers which you require?
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To +Lee Grupsmith-Pedersen and others who are interested

Why do we need to connect the Internet to phone numbers?
We've already installed many Android apps without needing a phone number.
In this case, why not use Hangouts?
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+John Baez and any other interested person,
I hurt when such a person dies because of sickness. This message does not describe this feeling, but I am open to sharing it. In order to replace this pain with other feelings, I help people stay healthy. I qualified as a therapist in 2002, then I moved to a small place with an environment appropriate for a spa. When I started looking for supporting staff, I asked myself whether a small team is enough. It took me some time to answer: No. So I started building a network of therapists: https://sites.google.com/idls.ro/sol/ask-for/healthcare
I am ready to talk with those whom this death hurts and to steer others towards a healthier life.
Maryam Mirzakhani, 1977 - 2017

She died yesterday, a mathematician who had not yet reached the height of her powers: the first Fields medalist from Iran, and also the first woman to win that honor. Here's what I wrote when she won:

As a child in Tehran, she didn't intend to become a mathematician - she just wanted to read every book she could find! She also watched television biographies of famous women like Marie Curie and Helen Keller. She started wanting to do something great... maybe become a writer.

She finished elementary school while the Iran-Iraq war was ending, and took a test that got her into a special middle school for girls. She did poorly in math her first year, and it undermined her confidence. “I lost my interest in math," she said.

But the next year she had a better teacher, and she fell in love with the subject. She and a friend became the first women on Iranian math Olympiad team. She won a gold medal the first year, and got a perfect score the next year.

After getting finishing her undergraduate work at Sharif University in Tehran in 1999, she went on to grad school at Harvard. There she met Curtis McMullen, a Fields medalist who works on hyperbolic geometry and related topics.

Hyperbolic geometry is about curved surfaces where the angles of a triangle add up to less than 180 degrees, like the surface of a saddle. It's more interesting than Euclidean geometry, or the geometry of a sphere. One reason is that if you have a doughnut-shaped thing with 2 or more holes, there are many ways to give it a hyperbolic geometry where its curvature is the same at each point. These shapes stand at the meeting-point of many roads in math. They are simple enough that we can understand them in amazing detail - yet complicated enough to provoke endless study.

Maryam Mirzakhani took a course from McMullen and started asking him lots of questions. “She had a sort of daring imagination,” he later said. “She would formulate in her mind an imaginary picture of what must be going on, then come to my office and describe it. At the end, she would turn to me and say, ‘Is it right?’ I was always very flattered that she thought I would know.”

Here's a question nobody knew the answer to. If an ant walks on a flat Euclidean plane never turning right or left, it'll move along a straight line and never get back where it started. If it does this on a sphere, it will get back where it started: it will go around a circle. If it does this on a hyperbolic surface, it may or may not get back where it started. If it gets back to where it started, facing the same direction, the curve it moves along is called a closed geodesic.

The ant can go around a closed geodesic over and over. But say we let it go around just once: then we call its path a simple closed geodesic. We can measure the length of this curve. And we can ask: how many simple closed geodesics are there with length less than some number L?

There are always only finitely many - unlike on the sphere, where the ant can march off in any direction and get back where it started after a certain distance. But how many?

In her Ph.D. thesis, Mirzakhani figured out a formula for how many. It's not an exact formula, just an 'asymptotic' one, an approximation that becomes good when L becomes large. She showed the number of simple closed geodesics of length less than L is asymptotic to some number times L to the power 6g-6, where g is the number of holes in your doughnut.

She boiled her proof down to a 29-page argument, which was published in one of the most prestigious math journals:

• Maryam Mirzakhani, Growth of the number of simple closed geodesics on hyperbolic surfaces, Annals of Mathematics 168 (2008), 97–125, http://annals.math.princeton.edu/wp-content/uploads/annals-v168-n1-p03.pdf.

This is a classic piece of math: simple yet deep. The statement is simple, but the proof uses many branches of math that meet at this crossroads.

What matters is not just knowing that the statement is true: it's the new view of reality you gain by understanding why it's true. I don't understand why this particular result is true, but I know that's how it works. For example, her ideas also gave here a new proof of a conjecture by the physicist Edward Witten, which came up in his work on string theory!

This is just one of the first things Mirzakhani did. She's now a professor at Stanford.

"I don't have any particular recipe," she said. "It is the reason why doing research is challenging as well as attractive. It is like being lost in a jungle and trying to use all the knowledge that you can gather to come up with some new tricks, and with some luck you might find a way out."

She has a lot left to think about. There are problems she has been thinking about for more than a decade. "And still there’s not much I can do about them," she said.

"I can see that without being excited mathematics can look pointless and cold. The beauty of mathematics only shows itself to more patient followers."

I got some of my quotes from here:

http://www.simonsfoundation.org/quanta/20140812-a-tenacious-explorer-of-abstract-surfaces/

and some from here:

http://www.theguardian.com/science/2014/aug/13/interview-maryam-mirzakhani-fields-medal-winner-mathematician

They're both good to read. For a mathematically informed obituary, see this by Terry Tao:

https://terrytao.wordpress.com/2017/07/15/maryam-mirzakhani/

The animated gif is a clip from this video:

https://www.youtube.com/watch?v=swLWqlKMl5M

#geometry
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If a summer is a maker of sums, what is a bummer?
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Which one is correct?
a. late summer
b. late Summer
Late Summer is not.
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