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= = =**Welcome to my Maths and Physics wiki.**=

It is certainly a work in progress and will be updated as and when I can. In the early stage I make no apologies that some of the material is in here solely because it is of interest to me even though it may be out of the student's sphere of understanding at the moment.

I did my first pacticum at South Otago High School and a lot of information can be put onto this wiki as is probably the easiest way to transfer files if I am out of town for the next practicum. That is not quite applicable as here I am in my second practicum at Kings High School here in Dunedin

Pupils generally enjoy carrying out experiments - but do teachers overuse them when they should in fact be teaching more theory, asks **Alom Shaha** Are physics experiments worth doing in the classroom[|?]

and if you are interested in some films of various physics phenomena then check this out [|http://www.iopblog.org/physics-planet-scicast-film-awards]

[|Physics video of the week: what is quantum tunnelling?]
A great video giving a perspective on quantum mechanical tunnelling

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Faster-than-Light Neutrino Puzzle Claimed Solved by Special Relativity
The relativistic motion of clocks on board GPS satellites exactly accounts for the superluminal effect, says physicist.

 KFC 10/14/2011 It's now been three weeks since the extraordinary news that neutrinos travelling between France and Italy had been clocked moving faster than light. The experiment, known as OPERA, found that the particles produced at CERN near Geneva arrived at the Gran Sasso Laboratory in Italy some 60 nanoseconds earlier than the speed of light allows. The result has sent a ripple of excitement through the physics community. Since then, more than 80 papers have appeared on the arXiv attempting to debunk or explain the effect. It's fair to say, however, that the general feeling is that the OPERA team must have overlooked something. Today, Ronald van Elburg at the University of Groningen in the Netherlands makes a convincing argument that he has found the error. First, let's review the experiment, which is simple in concept: a measurement of distance and time. The distance is straightforward. The location of neutrino production at CERN is fairly easy to measure using GPS. The position of the Gran Sasso Laboratory is harder to pin down because it sits under a kilometre-high mountain. Nevertheless, the OPERA team says it has nailed the distance of 730 km to within 20 cm or so. (call this my own gut feeling but I suspect that this is where the error or source of error arises)
 * 13 COMMENTS

The time of neutrino flight is harder to measure. The OPERA team says it can accurately gauge the instant when the neutrinos are created and the instant they are detected using clocks at each end. But the tricky part is keeping the clocks at either end exactly synchronised. The team does this using GPS satellites, which each broadcast a highly accurate time signal from orbit some 20,000km overhead. That introduces a number of extra complications which the team has to take into account, such as the time of travel of the GPS signals to the ground. But van Elburg says there is one effect that the OPERA team seems to have overlooked: the relativistic motion of the GPS clocks. It's easy to think that the motion of the satellites is irrelevant. After all, the radio waves carrying the time signal must travel at the speed of light, regardless of the satellites' speed. But there is an additional subtlety. Although the speed of light is does not depend on the the frame of reference, the time of flight does. In this case, there are two frames of reference: the experiment on the ground and the clocks in orbit. If these are moving relative to each other, then this needs to be factored in. So what is the satellites' motion with respect to the OPERA experiment? These probes orbit from West to East in a plane inclined at 55 degrees to the equator. Significantly, that's roughly in line with the neutrino flight path. Their relative motion is then easy to calculate. So from the point of view of a clock on board a GPS satellite, the positions of the neutrino source and detector are changing. "From the perspective of the clock, the detector is moving towards the source and consequently the distance travelled by the particles as observed from the clock is shorter," says van Elburg. By this he means shorter than the distance measured in the reference frame on the ground. The OPERA team overlooks this because it thinks of the clocks as on the ground not in orbit. How big is this effect? Van Elburg calculates that it should cause the neutrinos to arrive 32 nanoseconds early. But this must be doubled because the same error occurs at each end of the experiment. So the total correction is 64 nanoseconds, almost exactly what the OPERA team observes. That's impressive but it's not to say the problem is done and dusted. Peer review is an essential part of the scientific process and this argument must hold its own under scrutiny from the community at large and the OPERA team in particular. If it stands up, this episode will be laden with irony. Far from breaking Einstein's theory of relatively, the faster-than-light measurement will turn out to be another confirmation of it. Ref: arxiv.org/abs/1110.2685 : Times Of Flight Between A Source And A Detector Observed From A GPS Satellite.

[|Teaching vs. Learning]
This was going to be a Physics Motivational poster, but it isn’t. At the recommendation of the twitterverse, I took the physics part off. So, here is the poster. Click to Biggie Size Oh? So I am saying teachers are worthless? Or maybe that teachers are like the Emperor? Not at all. Well I am sure we have all had a teacher that was like the Emperor, right? I am saying that the word teacher maybe isn’t the best thing to associate with teaching. One of those words needs to change. Ok, I don’t want to over analyze my own poster. Instead let me make two points. First, I posted an early version of this poster on [|twitter]. Greg Memes ( [|@gregnemes] ) offer the very useful insight regarding the emperor. > …when I teach, I learn. And I see my students teach each other. Quite true. I considered changing the title underneath the Emperor and Luke to read: > The Emperor teaches Luke a lesson and learns that Luke has no defense against force lightning. That line ended up on the editing floor since it was too long – but still funny. There is one other thing that fell on the floor of editing. Originally, I wanted this to say something about physics. If you look at my previous [|Motivational Physics posters], they have a theme. The theme is: physics is difficult, and that is a good thing. There was a final line in this earlier version. It read: > Luke doesn’t work to become a Jedi because it is the easy path. Physics is difficult. But it was just too much. One more thing. This is why I call myself a “learning facilitator” and not a “teacher”. I want to be like Yoda, not the Emperor.
 * By [|Rhett Allain] [[image:http://www.wired.com/wiredscience/wp-content/themes/wired/images/envelope.gif width="14" height="11" caption="Email Author"]]
 * July 2, 2011 |
 * 9:36 am |
 * Categories: [|Dot Physics], [|Science Blogs]

Hubble Space Telescope: one in a million
July 6th, 2011 The **Hubble Space Telescope** has captured its [|**one-millionth scientific observation**]. To commemorate, here is more than 200 of the most spectacular **Hubble images**, set to music from the// [|**Planets**] // album by the **New York City** band [|**One Ring Zero**]. Many thanks to One Ring Zero co-leader [|**Michael Hearst**] for extending permission to use the song //Pluto// in this video. And thanks to NASA fan**Alex Grzybowski** of [|**Glenelg Country School**] for right-clicking more than 200 Hubble images off [|**Hubblesite**] for this project. [|Download] the video (.wmv, 4 Mb)

[|Download] the video (.m4v, 28 Mb)

Spend a Month at the Chicago Museum of Science and Industry The Museum of Science and Industry in Chicago is again looking for one lucky person to spend a month living among exhibits as part of its //Month at the Museum//. We’re hoping to get a Wired Science reader accepted. Then you can give us the inside scoop on what it’s like to wake up in the only World War II-era German U-boat recovered entirely intact, or next to an indoor 40-foot tornado. The winner will get full museum reign between Oct. 19 and Nov. 17, a $10,000 stipend and lots of audience envy. Last year’s winner, Kate McGroarty, told us what it was like to explore the corners of the museum, dine with astronauts and accidentally frighten maintenance workers on nighttime jogs. We can’t wait to hear what this year’s winner will be up to. Applications are due July 22. Details about how to apply are at the museum’s website.

//Image: The Month at the Museum 2 winner’s “cube.”// //(J.B. Spector/Museum of Science and Industry)//

===__Particle Physics and Faster-Than-Light Neutrinos… __ ===

 On September 22, an international team of researchers working on the OPERA project at the Gran Sasso research facility released a paper on some potentially physics-shattering findings: beams of neutrinos that had traveled from the CERN facility near Geneva to their detector array outside of Rome at a speed faster than light. (Read more about this __<span style="color: #000000; font-family: 'Trebuchet MS',Arial,Helvetica,sans-serif;">here __ and __<span style="color: #000000; font-family: 'Trebuchet MS',Arial,Helvetica,sans-serif;">here __.) Not a great deal faster, to be sure – only 60 //nanoseconds// faster than expected – but still faster. There’s been a lot of recoil from the scientific community about this announcement, and rightly so, since if it does end up being a legitimate finding then it would force us to rework much of what we have come to know about physics ever since Einstein’s theory of relativity. <span style="color: #3f4a50; font-family: Arial,Helvetica,sans-serif; font-size: 12px;">Of course, to those of us not so well-versed in particle physics *raises hand* a lot of this information can quickly become overwhelming, to say the least. Thankfully the folks at __<span style="color: #000000; font-family: 'Trebuchet MS',Arial,Helvetica,sans-serif;">Sixty Symbols __ have recorded this interview with two astrophysicists at the UK’s University of Nottingham. It helps explain some of the finer points of the discovery, what it means and what the science community in general thinks about it. Check it out!