general science

Predicting a supernova precursor (on SN2010mc)

A very interesting paper recently appeared in nature. It describes the detection of a precursor eruption of a supernova progenitor more than a month before the supernova explosion itself. It is particularly interesting because this detection was not serendipitous—it was based on my prediction.

Dust Dendrites

My wife and I had our kitchen renovated. Since this involved breaking a few walls (and cutting out a new window), we knew it would raise a lot of dust. Mind you, here in the middle east houses are built from concrete and concrete blocks, not wood. To minimize the dust annoyance (and damage), we decided to quarter off the living room from the kitchen by using large nylon sheets hung from the ceiling to the floor. 

After the dust settled down (literally…), we found something quite bizarre. The nylon walls developed very beautiful dust dendrites, akin to the more familiar frost dendrites (like these frost dendrites I have seen while living in Toronto). 

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Causes of Climate Change - Poll Results

Out of curiosity, I opened a few weeks ago a poll asking the visitors of this site, what do they think is the primary cause of global warming. 429 people answered the poll (thanks to all of you!).

The results can be summarized as follows.

First, the visitors of this site have the following background:
Background Fraction (Votes)
Layman 54.9% (232)
General Scientist 41.1% (174)
Climate Scientist 4.0% (17)

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On IPCCs exaggerated climate sensitivity and the emperor’s new clothes

A few days ago I had a very pleasant meeting with Andrew Bolt. He was visiting Israel and we met for an hour in my office. During the discussion, I mentioned that the writers of the recent IPCC reports are not very scientific in their conduct and realized that I should write about it here.

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What is your expertise, and what is the cause of 20th century climate change?

Laymen, mostly anthropogenic
2% (8 votes)
Laymen, mostly natural
45% (193 votes)
Laymen, nobody knows
7% (31 votes)
General scientist, mostly anthropogenic
1% (6 votes)
General scientist, mostly natural
33% (142 votes)
General scientist, nobody knows
6% (26 votes)
Climate scientist, mostly anthropogenic
0% (0 votes)
Climate scientist, mostly natural
3% (11 votes)
Climate scientist, nobody knows
1% (6 votes)
Have absolutely no idea what to answer
1% (6 votes)
Total votes: 429

Why don't I believe the that neutrinos travel faster than the speed of light?

Three weeks ago I visited the underground laboratory of Gran Sasso near l'Aquila. Little did I know that it would make headline news so soon, for "discovering" particles moving faster than the speed of light. Since a few people asked me what did I think of it, I decided to write something about it here.

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From Masada to the Messinian Salinity Crisis

Masada, the Dead Sea, the Messinian Salinity Crisis and Augustus Ceasar, all in one post.

A visit to Stromboli

Last May I had a conference in the island of Vulcano. During the conference I had a half day excursion to the Island of Stromboli, where I climbed the mountain and got to see one of the most impressive geological phenomena one can see... Here are my impressions, photos and even a movie of it.

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The oceans as a calorimeter


I few months ago, I had a paper accepted in the Journal of Geophysical Research. Since its repercussions are particularly interesting for the general public, I decided to write about it. It's called, using the "Oceans as a Calorimeter to quantify the solar radiative forcing".

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Touch and go - my worst landing ever


I recently returned from Lijiang (in Yunnan, China). One of my legs was a flight from Chengdu to Beijing, and it is certainly a flight I will never forget.

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Open convection cells over the Negev?

OpenCellRadar Jerusalem was under siege, again. Last time it was Bush. This time, it was snow because of which we had two snow days. So, I didn't have to teach and instead could build a snowman with my kids. I could also look at the rain radar, which appeared to exhibit a few interesting phenomena.

One of the phenomena appears to be that of open-cell convection, i.e., air rising (and precipitating) on the cell boundaries.

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A Nice Black Hole Merger Simulation

I recently stumbled upon a nice black hole merger simulation.
Since it is not in my habit of just regurgitating stuff I see on the internet, here is my added value. How can one estimate the quadrupole gravitational radiation of a binary? How close does the binary have to be for it to coalesce within the age of the universe?

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