Archive for the ‘Highlights’ Category

Flashback: First test of exotic space thruster ends in explosion

Thursday, January 1st, 2009

Over the holiday period the arXivblog is re-running the most popular posts from 2008

23 May 2008: First test of exotic space thruster ends in explosion

In 2006, Mason Peck at Cornell University in Ithaca dreamt up with an entirely new way to control satellites orbiting planets that have a magnetic field. The idea is based on the Lorentz force: that a charged particle moving through a magnetic field experiences a force perpendicular to both its velocity and the field.

Read on…

Flashback: Forget black holes, could the LHC trigger a “Bose supernova”?

Wednesday, December 31st, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

29 September 2008 : Forget black holes, could the LHC trigger a “Bose supernova”?

The fellas at CERN have gone to great lengths to reassure us all that they won’t destroy the planet (who says physicists are cold hearted?).

Read on…

Flashback: Cloaking objects at a distance

Tuesday, December 30th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

5 November 2008: Cloaking objects at a distance

One of the disadvantages of invisibility cloaks is that anything placed inside one is automatically blinded, since no light can get in.

Now Yun Lai and colleagues from The Hong Kong University of Science and Technology have come up with a way round this using the remarkable idea of cloaking at a distance. This involves using a “complementary material” to hide an object outside it.

Read on…

Flashback: Quantum communication: when 0 + 0 is not equal to 0

Monday, December 29th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

5 August 2008: Quantum communication: when 0 + 0 is not equal to 0

One of the lesser known cornerstones of modern physics is Claude Shannon’s mathematical theory of communication which he published in 1948 while juggling and unicycling his way around Bell Labs.

Shannon’s theory concerns how a message created at one point in space can be reproduced at another point in space. He calls the conduit for such a process a channel and the limits imposed by the universe on this process the channel capacity.

Read on…

Flashback: Do nuclear decay rates depend on our distance from the sun?

Sunday, December 28th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

29 August 2008: Do nuclear decay rates depend on our distance from the sun?

Here’s an interesting conundrum involving nuclear decay rates.

We think that the decay rates of elements are constant regardless of the ambient conditions (except in a few special cases where beta decay can be influenced by powerful electric fields).

So that makes it hard to explain the curious periodic variations in the decay rates of silicon-32 and radium-226 observed by groups at the Brookhaven National Labs in the US and at the Physikalisch-Technische Bundesandstalt in Germany in the 1980s.

Read on…

Flashback: Feline ballistics

Saturday, December 27th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

1 February 2008: Feline ballistics

Here’s a straightforward question in ballistics:

What velocity do you need to launch a 350 pound object over a 12.5 foot barrier that is 33 feet away?

Read on…

Flashback: First superheavy element found in nature

Friday, December 26th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

28 April 2008: First superheavy element found in nature

The hunt for superheavy elements has focused banging various heavy nuclei together and hoping they’ll stick. In this way, physicists have extended the periodic table by manufacturing elements 111, 112, 114, 116 and 118, albeit for vanishingly small instants. Although none of these elements is particularly long lived, they don’t have progressively shorter lives and this is taken as evidence that islands of nuclear stability exist out there and that someday we’ll find stable superheavy elements.

Read on…

Flashback: Rubik’s cube proof cut to 25 moves

Thursday, December 25th, 2008

Over the holiday period, the arXivblog is running a selection of the most popular posts from 2008

26 March 2008: Rubik’s cube proof cut to 25 moves

Last year, a couple of fellas at Northeastern University with a bit of spare time on their hands proved that any configuration of a Rubik’s cube could be solved in a maximum of 26 moves.

Now Tomas Rokicki, a Stanford-trained mathematician, has gone one better. He’s shown that there are no configurations that can be solved in 26 moves, thereby lowering the limit to 25.

Read on…

In case ya missed ‘em…

Sunday, August 3rd, 2008

The iced buns from the physics arxiv blog this week:

The Casimir conundrum

The painful search for gravitational waves

The day the solar wind disappeared

Why small black holes cannot grow

In case ya missed ‘em…

Sunday, July 27th, 2008

The baubles from the physics arXivblog this week:

Musical relativity

The puzzling wrinkles in graphene

Terminator 0.0.1 (alpha)

How likely is an avian flu pandemic?