On June 10 2012 01:01 rei wrote: Which makes a vast distance for 0.5 nanoseconds traveling in speed of light.
Not really "vast"0.5 nanoseconds at speed of light would be roughly half a foot, or ~15cm
Forum Index > General Forum |
GaiaCaT
35 Posts
June 09 2012 17:04 GMT
#1041
On June 10 2012 01:01 rei wrote: Which makes a vast distance for 0.5 nanoseconds traveling in speed of light. Not really "vast"0.5 nanoseconds at speed of light would be roughly half a foot, or ~15cm | ||
Cascade
Australia5405 Posts
June 10 2012 08:55 GMT
#1042
On June 10 2012 01:01 rei wrote: "neutrinos' speed is within 0.5 nanoseconds of light speed, with an error of 8 nanoseconds" speed has unit of distance light travels a year per second. Which makes a vast distance for 0.5 nanoseconds traveling in speed of light. On top of that the uncertainty is 8 nanoseconds? which can be both over and under that 0.5 nanoseconds of the speed of light measured. How do you make senses of this? wouldn't the error too large for this to be conclusive? It is techically true that speed is distance per time, but in this measurement, where they measure when the neutrino arrive, it makes sense to present the result in time. So what is actually meant is that the neutrinos arrive within 0.5 ns of the time where they would arrive, had they traveled at exactly the speed of light. A bit sloppy formulation maybe, but pretty clear if you read a bit between the lines. 0.5 +- 8.0 means that it is equal to light speed, within errors. Let me give an example first: You want to measure how far you can throw a ball. You expect yourself to throw 35 meters, so you draw a line 35 meters from the point you throw from. You throw the ball and measure that it went 34.5 meters, but you have an uncertainty on the measurement of 2 meters. This means that the measurement is in agreement with the prediction, as you measured within 0.5 meters of the line, but with a 2 meter uncertainty, it was expected to not measure exactly 35. You can present this result rhough saying that the ball hit within 0.5 meters of the 35-meter line, with an uncertainty of 2 meters. If you would have measure 40 meters, with a 2 meter uncertainty, then the measurement is not consistent with the ball being thrown 35 meters. In the same way with the neutrinos, they expect the neutrinos to arrive at a certain point in time if they travel at light speed. The see them arrive on average 0.5 ns before or after that. But they have a 8 ns uncertainty, so the measurement is consistent with the neutrinos traveling at light speed. What we have measured is that the neutrinos travel at around light speed, with an uncertainty corresponding to the 8 ns. Hope that made it clearer for you. | ||
Kyrillion
Russian Federation748 Posts
June 10 2012 09:14 GMT
#1043
I don't get why really scientists or people in general apply light as the fastest thing in the universe. I do get why it is the most well-known fastest observed speed in the physical universe, but I always thought there can always be something faster. My level in physics is still low but as I've understood it, theory strongly suggests there is a maximal speed. This maximal speed appears in the Lorenz transformate formulas, and those formulas can be checked by doing experiments in, for instance, particle accelerators. If the measures we do in the experiments confirm accurately the formulas using the speed of light as "c", then it would appear that c, the maximal speed, is indeed the speed of light or at least something extremely close. | ||
EatThePath
United States3943 Posts
June 10 2012 09:20 GMT
#1044
On June 10 2012 18:14 Kyrillion wrote: Show nested quote + I don't get why really scientists or people in general apply light as the fastest thing in the universe. I do get why it is the most well-known fastest observed speed in the physical universe, but I always thought there can always be something faster. My level in physics is still low but as I've understood it, theory strongly suggests there is a maximal speed. This maximal speed appears in the Lorenz transformate formulas, and those formulas can be checked by doing experiments in, for instance, particle accelerators. If the measures we do in the experiments confirm accurately the formulas using the speed of light as "c", then it would appear that c, the maximal speed, is indeed the speed of light or at least something extremely close. You can read a decent synopsis here. | ||
SEA KarMa
Australia452 Posts
June 10 2012 09:22 GMT
#1045
| ||
hefty
Denmark555 Posts
June 10 2012 09:31 GMT
#1046
I don't get why really scientists or people in general apply light as the fastest thing in the universe. I do get why it is the most well-known fastest observed speed in the physical universe, but I always thought there can always be something faster. It isn't just an assumption. It is the foundation of our understanding of how time, space and matter interacts. So it is not like we can just assume that "there probably is something faster out there in the great universe", because it would have great consequences for our understanding of the world. | ||
nihlon
Sweden5581 Posts
June 10 2012 09:49 GMT
#1047
On June 09 2012 21:36 Dislexic wrote: Incase anyone was interested and hasn't seen, this has been debunked recently. http://www.newscientist.com/article/dn21899-neutrinos-dont-outpace-light-but-they-do-shapeshift.html I don't get why people keep using the word debunked here, they never claimed this as fact. They wanted an explanation and they got one, that's how science works. Debunking is when someone claims they have invented an infinity/cold fusion/whatever machine and then they get hit over the head by reason. | ||
radiatoren
Denmark1907 Posts
June 10 2012 10:54 GMT
#1048
1. Theory vs. experiment. The original results were interesting, but not so much because of theoretical conflicts as it was made out in the media. It is quite a setup to get this experiment running and even getting consistent results is an achievement. That the results did not match theory is pointing towards a systematic error. The setup is very complex and finding that needle in the haystack is very important for experimental physics for future experimental setups. Theoretical physics is a completely different discussion, where the theory can be fitted to reality. From a theoretical point of view, the OPERA-experiments were pretty interesting but - positive for the sanity of many scientists - wrong. 2. Scientific facts vs. scientific results vs scientific errors. Scientific facts are derived from several independent experiments with consistent and similar resuits. The experimental setups have to be different if there is any chance of a systematic error caused by the setup or alternatively you make blind samples, comparative samples etc. The OPERA-experiment was a scientific result.. Scientific results are what gets reported in journals or archives and they are very important for finding the future scientific facts. The problem with scientific results is that they are prone to errors in setup. Scientific errors are everywhere and in some fields they are an accepted part of life. When they are part of life you learn to take account of them by making enough repetitions to reduce fluctuations and you make mathematical corrections for known systematic biases. Every kind of experiment has their own signature of errors and uncertainty. Eliminating fluctuations and correcting for known systematic biases are an art-form and one with amazing progress made every day. The OPERA-experiment was a huge succes in terms of experimental setup. They eliminated a lot of fluctuation of the previous experiments and they succesfully ended up finding a less common systematic error. Most pop-science journalists focus on the theory vs experiment and they end up concluding that the fracking experimentalists are a bunch of Boso the Clown-imitators. In reality the OPERA-experiments have provided a lot of improvement towards physical experimental setup and some very good results for future reference. You have to be aware of those destinctions to understand why the pop-science journalists, to some extend, are the Clowns here. | ||
| ||
ESL Pro Tour
Spring 2024 - Europe Round 4
[ Submit Event ] |
StarCraft 2 StarCraft: Brood War Britney 45359 Dota 2Calm 4518 GuemChi 877 Shuttle 581 Stork 524 Hyuk 424 ggaemo 406 Snow 402 Mini 289 Light 260 [ Show more ] Counter-Strike Other Games singsing2326 hiko934 DeMusliM712 Hui .632 B2W.Neo554 crisheroes546 Pyrionflax312 QueenE94 NuckleDu74 Kaelaris44 Crank 37 Organizations
StarCraft 2 • LUISG 4 StarCraft: Brood War• Kozan • LaughNgamez Trovo • Poblha • Migwel • aXEnki • intothetv • Gussbus • Laughngamez YouTube • IndyKCrew Dota 2 League of Legends |
Big Brain Bouts
ESL Pro Tour
Online Event
ESL Pro Tour
OSC
OSC
ESL Pro Tour
BSL
TerrOr vs Sziky
Nyoken vs Zhanhum
Sparkling Tuna Cup
ESL Pro Tour
[ Show More ] ESL Pro Tour
BSL
Bonyth vs StRyKeR
DragOn vs MiStrZZZ
ESL Pro Tour
ESL Open Cup
ESL Open Cup
ESL Open Cup
ESL Pro Tour
ESL Pro Tour
PassionCraft
ESL Pro Tour
ESL Pro Tour
|
|