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JonathanWilson 10-25-2011 10:18 AM

CERN faster than light.
 
I wonder, if light as theorized is a constant and unchangeable by speed of movement of an object containing the emitted light did CERN take into account the rotation of the earth, the movement of the earth through the solar system, the movement of the solar system through the galaxy and finally the galaxy through the universe... perhaps the test gave the result as it was aligned exactly to a path of movement that meant the sender and receiver of the test were traveling at such velocity as to reduce the amount of space between the two parts of the equipment during the measurement?

corp769 10-25-2011 10:21 AM

Honestly, I think I will be able to understand this better once you add in some proper punctuation.... Just an FYI ;)

But I think that they need to do more testing and observations, among theory and everything else that is part of it. My honest opinion is that they need to keep trying to reproduce it to get better results.

salasi 10-25-2011 12:25 PM

Quote:

Originally Posted by JonathanWilson (Post 4507804)
I wonder, if light as theorized is a constant and unchangeable by speed of movement of an object containing the emitted light did CERN take into account the rotation of the earth, the movement of the earth through the solar system, the movement of the solar system through the galaxy and finally the galaxy through the universe... perhaps the test gave the result as it was aligned exactly to a path of movement that meant the sender and receiver of the test were traveling at such velocity as to reduce the amount of space between the two parts of the equipment during the measurement?

This is at least the third thread on this subject here, and that's at least two too many and it may even be three too many.

The results have already been looked at by respectable scientists (not the lot who first got the data) and the reason for publication is that they have not yet come to a conclusion that would not cause concerns. The idea of publication is that other scientists might have some explanation that doesn't cause a large-scale re-interpretation of the laws of physics. You have to bear in mind that these results come from measurements on something that is, by definition, difficult to measure (the main thing about neutrinos is that they hardly interact with anything, ever, and you need the interaction with the measuring equipment to give you the correct results) and which depend on statistics.

In comparison, you want to question (I think) whether the physicist have understood basic relativity; I think that at least one of the physicists will understand relativity well enough and think that there is a better chance that they have the stats wrong (which is sad, but no one understands stats, it seems). I'm still not dismissing the idea that it is genuinely the universe that we don't understand, but there are certainly other options.

David the H. 10-26-2011 01:02 PM

As mentioned, the FTL measurement was based on statistical analysis of the neutrino "hits" received. Anything that could skew the distribution, or any flaw in the analysis, could result in a false reading. Not to mention that this finding contradicts all previous measurements done over the last hundred years.

Even if no errors are found, it will certainly require additional positive tests before the current theories can truly be considered compromised. A single anomalous data point is not generally enough to topple a 100-year-old theory.


I posted this commentary by a real physicist in the last thread that came up, but I think it's appropriate to post it again here.

http://www.physorg.com/news/2011-10-...-theories.html

moxieman99 10-26-2011 03:02 PM

It appears that the observers did not take into account, and adjust for, the relative motion of the GPS satellites being used to provide the time signals. The failure to do so injected a 64 nanosecond error into the measurement, neatly covering the alleged faster-than-light time difference.

Rather than defying Einstein, the test seems to have confirmed him.

jlinkels 10-26-2011 07:02 PM

Quote:

Originally Posted by JonathanWilson (Post 4507804)
I wonder, if light as theorized is a constant and unchangeable by speed of movement of an object containing the emitted light did CERN take into account the rotation of the earth, the movement of the earth through the solar system, the movement of the solar system through the galaxy and finally the galaxy through the universe... perhaps the test gave the result as it was aligned exactly to a path of movement that meant the sender and receiver of the test were traveling at such velocity as to reduce the amount of space between the two parts of the equipment during the measurement?

Nope. Relativity theory says that the speed of light is always constant for the observer. That precludes that movement of something can influence that observation. Simply said, if you move towards a light source with a speed of 100.000 km/s, you still see the speed of light as 300.000 km/s. That is strange because your speed towards the source is 100.000 km/s, and you'd expect those speeds would add. They don't. Same thing, if you move away from a light source with 100.000 km/s and this light source sends a light pulse towards you, you observe the speed of this pulse with 300.000 km/s.

That is because at low speeds which we normally observe, speeds can be added and subtracted, and speed = distance / time. At speeds close to the speed of light that ain't true anymore. Since speed is a given (you are moving, right) either distance or time distorts.

I don't know what they found at CERN, but although the speed of light is fixed and well-known and the relativity theory is constructed around it, there have been doubts for a longer period of time that transfer of information could be faster than the speed of light.

jlinkels

David the H. 10-27-2011 10:42 AM

Quote:

Originally Posted by moxieman99 (Post 4509135)
It appears that the observers did not take into account, and adjust for, the relative motion of the GPS satellites being used to provide the time signals. The failure to do so injected a 64 nanosecond error into the measurement, neatly covering the alleged faster-than-light time difference.

Rather than defying Einstein, the test seems to have confirmed him.

I haven't heard this, but I wouldn't be surprised. Any links to the story? I'd like to read up on it.

OTOH, I was under the impression that the GPS satellites already handled this internally. Each one contains a hyper-accurate atomic clock for the purposes of compensating for their relativistic motion. Not that I have any idea how it works, exactly. :scratch:

mjolnir 11-29-2011 11:00 AM

"Faster-Than-Light Neutrinos Re-Tested: Same Result
CERN's OPERA experiment continues to clock the subatomic particles traveling faster than the speed of light.


Fri Nov 18, 2011 01:17 PM ET"

http://news.discovery.com/space/fast...mkcpgn=rssnws1

@David the H.
Here is a d/l link to one of the papers.
http://arxiv.org/pdf/1111.4994v2

Good luck, my eyes glazed over slightly after I got past the intro. :-)

mjolnir 12-05-2011 09:46 AM

More on the subject: "A chorus of critiques from physicists soon followed. Among other possible errors, some suggested that the neutrinos generated at CERN were smeared into bunches too wide to measure precisely.

So in recent weeks, the OPERA team tightened the packets of neutrinos that CERN sent sailing toward Italy. Such tightening removed some uncertainty in the neutrinos’ speed.

The detector still saw neutrinos moving faster than light.

“One of the eventual systematic errors is now out of the way,” said Jacques Martino, director of the National Institute of Nuclear and Particle Physics in France, in a statement.

But the faster-than-light drama is far from over, Martino added. The OPERA team is discussing more cross-checks, he added, including possibly running a fiber the 454 miles between the sites."

http://www.washingtonpost.com/nation...TWN_story.html

H_TeXMeX_H 12-06-2011 10:49 AM

It is no error, but they will try their hardest to make it one. It may well bring their house of cards crashing down. They better think of something fast. Maybe they should write something up and claim they discovered that Einstein actually knew this and explained it away somehow.

JonathanWilson 12-06-2011 12:22 PM

I was dream thinking (Lucid dreaming) last night about FTL and was therefore quite surprised to see this post today :-O

However.. one thing that came to mind was that traveling faster than light doesn't cause any possibility of time travel as the mainstream press (BBC/ITV/SKY, et. al.) seemed to say it did, and the odd talking head who was interviewed seemed to think it did.

The explanation in simple terms was thus... if it traveled faster than light it would mean the possibility of recieving a text message reply to a text message not already sent.

However this is obviously not true as the experiment proved, after all if true, the particles traveled faster than light yet were received with a record-able time delay from when they were sent, had they broken some form of time travel then it would be expected that they would have arrived before they were sent.

Surely it does not matter how much quicker than light something is traveling, it still would take a determinable amount of time to travel.. only if it exceeded infinity would it truely be able to travel through time.

I can see that something traveling faster than light might affect the observation of time when light is used as a measure of a time constant (was this what Einstein meant?) but even if I traveled the distance from the earth to the farthest discovered galaxy and back in one second then surely only one second of time has elapsed both on earth and by the traveler not as postulated that the time passed on earth would be greater than for the traveler.

... Oh mind you... if i did do such a trip and say blew up a sun while I was there it would take the light from the distant galaxy millions of years to return to earth before the sun was observed to have blinked out of existance... mind you again that still wouldn't be time travel, mearly that light was slower than my travel.

Don't you just love theoretical science ;-)

Cedrik 12-06-2011 03:17 PM

Quote:

Originally Posted by JonathanWilson (Post 4543609)
but even if I traveled the distance from the earth to the farthest discovered galaxy and back in one second then surely only one second of time has elapsed both on earth and by the traveler not as postulated that the time passed on earth would be greater than for the traveler.

What about if you went to this farthest galaxy, observe the Earth from there with a telescope and see images of ancient history

sundialsvcs 12-10-2011 06:09 AM

I have always suspected that we suppose that "nothing can travel faster than light" for two, probably erroneous reasons:
  • Light, and electricity, is what we are doing the measuring with.
  • We are supposing that "the shortest distance between two points is a straight line," but that means that we never read the book, A Wrinkle in Time. What if space/time can be "folded?" And if it is, or can be, how would we possibly know?

There are, like it or not, real limits both to what we "know" and perhaps to what we can "know." This apparent discovery doesn't surprise me. The notion that it comes as some kind of a surprise, does.

Most of the things that we "know" are actually either conjecture, or religious belief. The entire topic of "scientific philosophy" (or "the philosophy of science," a.k.a. "thinking about thinking") is very fascinating to me. Given that there are just so many things that we want to "know about" but (apparently) cannot directly observe, the topic of how we can usefully obtain knowledge about such things (and of the process that we use to go about it) is a fascinating human study. (How does the blind man get along, and also avoid getting stepped-on by that elephant?)

mjolnir 02-23-2012 08:59 AM

Update: No time travel yet. :-) http://blogs.nature.com/news/2012/02...le-errors.html

“The OPERA Collaboration, by continuing its campaign of verifications on the neutrino velocity measurement, has identified two issues that could significantly affect the reported result. The first one is linked to the oscillator used to produce the events time-stamps in between the GPS synchronizations. The second point is related to the connection of the optical fiber bringing the external GPS signal to the OPERA master clock.

These two issues can modify the neutrino time of flight in opposite directions. While continuing our investigations, in order to unambiguously quantify the effect on the observed result, the Collaboration is looking forward to performing a new measurement of the neutrino velocity as soon as a new bunched beam will be available in 2012. An extensive report on the above mentioned verifications and results will be shortly made available to the scientific committees and agencies.”

Caren Hagner, a member of OPERA at the University of Hamburg in Germany, says “For the moment the collaboration decided not to make a quantitative statement, because we have to recheck and discuss the findings more thoroughly.”

sundialsvcs 02-23-2012 05:24 PM

We also need to be aware of the potential bias caused by two important considerations:
  1. Light/Electricity is the fastest thing we know about.
  2. Electricity is what drives all of our measuring devices, all of our accelerators, and so on!

Every theory starts as a hypothesis. Then, if enough seemingly-objective evidence seems to support it, it becomes a theory. The accepted rules of discourse always require you to presume that the theory is true and that any measures to the contrary surely are wrong ... but ... there is always that part of you who would love to be the one to win that next Nobel Prize in Physics! :D

It has always intuitive sense of "rightness" that Einstein's theory was, perhaps unavoidably, based on the edge-case of "the fastest thing that we know about." It is also based on the assumption (challenged by every science-fiction writer since then) that the only way to get from Point-A to Point-B is in a straight line.

Thus, I think that we should "delightfully expect" to one day be presented with the irrefutable fact that there is an entire universe of possibilities out there that Einstein (quite necessarily...) excluded in his time. But, y'know, isn't that what scientific discovery is all about? Isn't that what makes it so much fun??


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