Physics News of the Week: a Tabletop Gravitational Wave Detector

| December 1, 2014 | 0 Comments

The last week of autumn has passed and it’s time to take a look at some of top research done last week. Here are the top 3 news stories, plus some additional links. If you would like to receive these news straight to your email box, register for our email newsletter.

1. Researchers Tackle Inner Secrets of Neutron Stars (Nov 24)

Although what we call neutron stars are made mainly of neutrons, mystery surrounds the true nature of the matter contained deep within them. Now, thanks to the new research by  Mark Alford and Kai Schwenzer of Washington University, scientists can constrain what form of matter these dense objects, known as pulsars, might take.

All known matter is made of quarks and is held together – or “confined” – by strong interactions in the form of hadrons. The matter in neutron stars, however, could well be more exotic. Researchers have, in the past, looked at LMXB (low mass X-ray binary stars) data to rule in or out possible forms of matter that neutron stars might take, but LMXBs are messy systems and the rate at which they spin tells us little about their interior. What Alford and Schwenzer have done is to find a way to connect previously existing data from millisecond pulsars to the stars’ interior properties – without having to use temperature measurements. For a more detailed description use the link above.


Another significant step towards quantum computers

2. New Largest Number Factored on Quantum Device  (Nov 28)

So the largest number recently factored on a quantum device is 56,153. Doesn’t sound very impressive right? Well, believe it or not, it is quite impressive taking into account that this simple breakthrough is another big step towards functional quantum computers. The previous record of 143 that was set in 2012 was smashed by using the same room-temperature nuclear magnetic resonance (NMR) experiment with additional improvements.

“We’re still a far way from outperforming classical computers,” co-author Nike Dattani commented. “The highest RSA number factored on a classical computer was RSA-768, which has 768 bits, and took two years to compute (from 2007 to 2009).”

3. Tabletop Experiment Could Detect Gravitational Waves (Nov 28)

Wouldn’t it be ironic if a coin-sized detector observed gravitational waves before the giant Laser Interferometer Gravitational-Wave Observatory (LIGO)? Believe it or not, such a possibility is not as inconceivable as it might sound. Recently, a tiny detector has been designed by Dr Maxim Goryachev and Professor Michael Tobar at The University of Western Australia.

Traditionally the so-called resonant-mass detectors have employed metal bars about a metre long and around a tonne in weight, which makes them sensitive to gravitational waves with frequencies up to about a few kilohertz. The problem with such detectors is that gravitational waves are very hard to distinguish from thermal noise at the mentioned frequencies. Dr Goryachev and Professor Tobar overcame this problem by targeting gravitational radiation in the 1-1000 MHz range and operating at 0.01 K above zero. This enables a massive reduction in size of the detector: it now consists of a quartz disc about 2.5 cm in diameter hinged to another piece of quartz and placed in a vacuum chamber. A passing high-frequency gravitational wave would cause the disc to vibrate, setting up standing waves of sound across the 2 mm thickness of the disc.

Other news:



Tags: , , ,

Category: News

Leave a Reply

Your email address will not be published. Required fields are marked *