* Posts by Mallorn

18 publicly visible posts • joined 16 Feb 2011

Socket to the energy bill: 5-bed home with stupid number of power outlets leaves us asking... why?

Mallorn

Re: priorities

It's even worse if the usage of 'amount' is correct. Although from the pictures it looks like they would need a few more sockets before they became uncountable.

Boffins: Large Hadron Collider NOW movin', we're getting down and crush groovin'

Mallorn
Boffin

ATLAS Pictures

This is the first experiment I have ever worked on where I find myself learning updates in the press before colleagues...mind you I'm in Western Canada and have only just got up and checked the web before email. If you are interested there are picture of it hitting the ATLAS detector here:

https://twiki.cern.ch/twiki/bin/view/AtlasPublic/EventDisplayRun2Start

but the beam is only at the injection energy of 450 GeV from the SPS. The real test will be when they accelerate the beams to 6.5TeV each which requires the full 11kA current in the magnets. That's when we will learn if the 2 years of repairs worked and the magnets can handle the current...so fingers crossed with a little luck this time our understanding of the universe will break before the machine!

Kip Thorne explains how he created the black hole for Interstellar

Mallorn

Re: Just Down The Road.

That's not necessarily a good thing. There is nothing worse for destroying the immersive feeling of something than, just after arriving at an alien planet they wander into a city and your first reaction is "Hey that's Edmonton!". Simon Fraser University next door in BC is a particularly common location and has been in Stargate SG1 and Battlestar Galactica: apparently 1960's concrete looks 'alien'.

Production-ready ZFS offers cosmic-scale storage for Linux

Mallorn

Re: A more important ZFS feature

Silent? As in one of your disks has failed but you won't notice a thing until a second one dies and the whole FS gets irretrievably corrupted? How about we go for automatic with lots of warnings instead?

Lightspeed variable say intellectuels français

Mallorn
Boffin

Definitely not infinite

It cannot be infinite. The best way to think of this paper is that there is a fundamental maximum speed in the universe defined by the properties of space-time. Then there is the speed of light. Generally these two values are so incredibly close to each other that we can think of them as one and the same. However light interacts with the virtual particles in vacuum and so sometimes has a speed which almost imperceptibly less than the fundamental maximum. Essentially this is the same effect as the slower speed of light in water where photons interact with the water molecules and so are slowed down.

LHC spots mesons flipping between matter and antimatter

Mallorn
Stop

Re: Prists versus scholars

"What productivity that has helped humanity has come from knowing that there are particles smaller than we can use in life have there been?"

Says the person posting a message on a website using a computer. The fact that you have a computer is because 100 years ago Rutherford was bouncing alpha particles of a gold foil and Schrodinger, Heisenberg et al were developing quantum mechanics. Oh and the web itself was invented by CERN to help large, international groups of particle physicists to communicate with each other. So how about we start with those two.

Mallorn
Boffin

Re: I'm confused

"If a meson is composed of both a quark and an anti-quark, how can it have an anti-partner?"

D0 meson = charm quark + up anti-quark

anti-D0 meson = charm anti-quark + up quark

Since a charm quark is distinct from a charm anti-quark these are two different particles. However you can get mesons consisting of the quark and anti-quark of the same flavour (e.g. phi meson = strange+anti-strange). These are their own anti-particles just like a photon!

Tesla drops veil on top secret solar Superchargers

Mallorn
Stop

Re: Drive anywhere for free...

Anywhere? Try getting up to Yorkshire and see how far your Oyster card gets you! Mind you a solar powered charger wouldn't help you much for that journey either.

NASA working on faster-than-light drive capable of WARP TEN

Mallorn
Boffin

Re: Oh noes!

"when simultaneity and causality aren't well-defined concepts anyway."

Depends which universe you are living in. In mine they are very well defined: simultaneous events are ones which occur at the same time according to an observer and causality requires that if event A causes event B event A had better have occurred before event B for all observers.

US sets up underground dark matter detector

Mallorn
Boffin

Correction

"That detector helped 2002 Nobel Laureate the late Dr Ray Davis detect “flavor (sic) changes” in solar neutrinos"

Ray Davis did not detector flavour changes in solar neutrinos! He detected a shortfall in the number of electron neutrinos predicted by solar models but did not make any measurement which showed why there was such a shortfall. This lead to what was called the "solar neutrino problem" where multiple experiments confirmed that the electron neutrino flux was only ~33-50% of what was expected.

If was the Sudbury Neutrino Observatory (SNO) [http://www.sno.phy.queensu.ca/] which showed that solar neutrinos changed flavour by measuring the total flux of all flavours vs. the flux of just the electron flavour.

Not convinced? Check the Nobel prize citation for Davis: "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos" [http://www.nobelprize.org/nobel_prizes/physics/laureates/2002/] - no mention of flavour oscillations!

Mallorn
Boffin

Re: self contradictory

" A neutrino smacking into something can cause Cherenkov radiation"

Not quite. A neutrino with sufficient energy which hits something and interacts (the latter is very unlikely) can either convert into the same flavour of charged lepton (electron, muon or tau) or can kick an electron out of matter.

It is this high energy charged particle which causes the Cherenkov radiation, not the neutrino itself because you have to have a charge to generate Cherenkov light. Also Cherenkov radiation is not one photon but a whole series emitted in a cone similar to the sonic boom of a supersonic plane but with light, not sound. The frequency of the radiation is determined by the refractive index of the material.

You're crap and paid too much for the little work you actually do

Mallorn
Thumb Up

Re: I do know the difference between sysadmin and programming

"It may be my fault, but it is your problem"

I think that might be the best bit of advice you've given and one that seems to have escaped the notice of most of the commenters here. It's also good advice for academia too - not that we get to negotiate pay rises! However in general you have to work around the problems with the system until you get to the point where you can fix them...and replace them with different problems of your own making which others will then have to live with! ;-)

Fusion boffins crack shreddy eddy plasma puzzle

Mallorn
Boffin

General Fusion

If you are interested in fusion research you should have a look at General Fusion - a company based in Vancouver. They are developing a different type of reactor which uses a spinning ball of lead which is symmetrically compressed by steam pistons to compress injected plasma toroids to the point of fusion. A lot of the neutrons generated are trapped by the molten lead which is laced with lithium to breed tritium fuel.

No idea whether the technology will work well enough to let them succeed but the basic physics principles look sensible (to a physicist, but not a plasma physicist).

Bill Gates strangled Microsoft's 'tablet for creatives'

Mallorn
Coat

Old saying

MS should really have remembered the old saying "don't shoot the messenger" before they killed the courier.

Reg hacks confront really wide Oz load terror

Mallorn
Boffin

I'll see your prefab house...

...and raise you a particle physics experiment to measure the neutrino mass: http://www.aspera-eu.org/index.php?option=com_content&task=view&id=140&Itemid=98.

CERN 'gags' physicists in cosmic ray climate experiment

Mallorn
Stop

Request, not order

Speaking as a particle physicist who works at CERN, but with nothing whatsoever to do with CLOUD, I think the article grossly misrepresents the facts. First Rolf has requested that they refrain from interpretation of their results NOT that they do not publish them i.e. the data will still be out there in the public domain for all to interpret. Secondly the DG of CERN has no ability to prevent experiments at CERN from publishing whatever they like. Technically he may be able to make CERN employed personel remove their names from the paper (although that's not for certain) but most of us working at CERN have positions in external institutes and have the protection of tenure (at least those of us not in the UK) for precisely this reason: we can publish what we like without fear for our jobs.

Of course you would not lightly ignore the request of the CERN DG, especially when it is a sensible, well reasoned request such as this (sticking to the data is good science and avoids unnecessary politics). However it is a request.

Dim Brits think TARDIS IS REAL

Mallorn
Boffin

Not necessarily...

"By definition, if time travel was to be possible ever, it would be possible now."

Not true. General relativistic time travel using a pair of connected worm holes would only allow time travel back to the point when the wormholes were created and not before. So it is at least conceivable that time travel might be possible in the future without us knowing about it today (although I doubt it!).

Boffins demand: Cull bogus A-Levels, hire brainier teachers

Mallorn

Not just filling in paperwork

It's not just filling in paperwork. My sister is one of the rare primary school science teachers and her problem is that she is heavily restricted in what she can do. For example she got together with secondary school science teachers to arrange a program where pupils in the final year of primary got to go to the secondary school and use some of the more advanced lab apparatus. However this was nixed because it wasn't safe for them to be in a secondary school lab (with teacher present)...although magically the following year it all suddenly became ok.

Frankly I think the Royal Society has got it completely wrong. You attract good teachers by allowing them to take the initiative and make a difference. Good teachers will make subjects more attractive to students and give good advice. Diluting subjects in the hope that if you take enough "A" levels students can't avoid hitting at least one science subject is daft because then when they get to university they will know even less making the job of us university profs even harder.