Approximately three hours before the visible light from SN 1987A reached the Earth, a burst of neutrinos was observed at three separate neutrino observatories. This is likely due to neutrino emission (which occurs simultaneously with core collapse) preceding the emission of visible light (which occurs only after the shock wave reaches the stellar surface). [9] At 7:35 a.m. Universal time, Kamiokande II detected 11 antineutrinos, IMB 8 antineutrinos and Baksan 5 antineutrinos, in a burst lasting less than 13 seconds.

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SN1987A, A Retrospective Analysis Regarding Neutrino Speed

In 1987 the physics community was surprised by a fortuitous supernova. The light from the supernova reached Earth on February 23, 1987, and as it was the year’s first supernova, it was designated SN1987A. The parent star was located approximately 168,000 light-years away, in the Large Magellanic Cloud, which is the Milky Way’s companion dwarf galaxy. It became visible to the naked eye in Earth’s southern hemisphere.

In this observation, a star core collapsed and released a lot of energy. Most of the excess energy is predicted in theory to be radiated away in a ‘cooling phase’ massive burst of neutrinos/anti-neutrinos formed from pair-production (80-90% of the energy release) and these neutrinos would be of all 3 flavors, both neutrinos and anti-neutrinos, while some 10-20% of the energy is released as accretion phase neutrinos via reactions of electrons plus protons forming neutrons plus neutrinos, or positrons plus neutrons forming protons plus neutrinos (1 flavor, neutrino and anti-neutrino). The observations are also consistent with the models' estimates of a total neutrino count of 10^58 with a total energy of 10^46 joules.

Approximately three hours before the visible light from SN 1987A reached the Earth, a burst of neutrinos was observed at those three separate neutrino observatories. This is due to neutrino emission (which occurs simultaneously with core collapse) preceding the emission of visible light (which occurs only after the shock wave reaches the stellar surface). At 7:35 a.m. Universal time, Kamiokande II detected 11 antineutrinos, IMB 8 antineutrinos and Baksan 5 antineutrinos, in a burst lasting less than 13 seconds.

In this respect, a point that deserves to be stressed is that all 3 detectors observed a relatively large number of events in the first one second of data-taking, about 40% of the total counts (6 events in Kamiokande-II, 3 events in IMB and 2 events in Baksan), while the remaining 60% were spread out over the course of the next 12 seconds.

In other words, these neutrinos travelled a total distance of 5.3 X 10^12 light seconds (168,000 light years), with almost half originating at roughly the same time (within about a 1 second burst of neutrino emission), and all arrived at earth (the light-transit time of earth's diameter is << 1 second and is not a factor due to the spacing of the detectors) within about 1 second of each other. In other words, they all travelled at close to the same speed to within nearly 13 orders of magnitude (5.3 X 10^12 seconds/1 second), far greater than any other measurement precision ever made for the speed of light. And, they all travelled at very close to the speed of light (travelling the same distance as the photons that reached Earth 3 hours later) at a speed consistent to c to within about 1 part per 500 million).

One would expect that since the neutrinos are emitted with potentially a range of energies, that their transit time would have exhibited a range of speeds (all in the 0.9999+ c speed range) if they were sub-luminal particles. While it has been believed that because the total ‘rest-energy’ of a neutrino is on the order of a few eV, while the rest-mass of an electron is about 511 KeV, neutrinos would all travel at close to c if they have mass and high-energy. But the energy they carry is sufficient to bring their speed to near c to only about .999999+ c if they are mass-particles, and the range in energies from pair-production should produce a spread in those speeds, albeit at many significant figures beyond the first few 9s. The calculated energy is indeed high, but not infinite. But that is not what was observed. They were observed to have all travelled at the same speed to 13 significant figures. In other words, had they had slight variations in their speed all slightly less than c, they would have had a large spread in the arrival time at Earth, on the order of days to years. The actual observation is far more consistent with neutrinos as having zero rest mass, and traveling at c, and appears wholly inconsistent with having a rest-mass and ejected with a spectrum of varying energies.

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http://en.wikipedia.org/wiki/Supernova_1987A

http://www.sciforums.com/showthread.php?t=110170

There are some fundamental questions being asked about "Does the Standard Model really work?" and "does eleventh dimensional space provide for the solution of the problem with neutrino mass?"

http://hitoshi.berkeley.edu/neutrino/PhysicsWorld.pdf

A short excerpt.

We are at an amazing moment in the
history of particle physics. The Higgs
boson, the mysterious object that fills
our universe and disturbs particles, will
be found sometime this decade, and
evidence for neutrino mass appears
very strong. The Standard Model,
which was established in late 1970s and
has withstood all experimental tests,
has finally been found to be incomplete.
To incorporate neutrino mass
into the theory – and to explain why it
is so small – requires major changes
to the Standard Model.We may need
to invoke extra dimensions or we may
need to abandon the sacred distinction
between matter and antimatter. If the
latter is the case, neutrino mass may
reveal the very origins of our existence.
One thing is certain, we are sure to learn a lot more about
neutrinos in the coming years

There are some fundamental questions being asked about "Does the Standard Model really work?" and "does eleventh dimensional space provide for the solution of the problem with neutrino mass?"

I wonder if the person who wrote this thinks the kind of changes to the standard model will be anything like all the changes string theory has gone through over the last 30 years to try to account for the actual properties of our universe?

11- Dimensions have no empirical support, it is a fabrication out of a wild attempt to understand a bottom up approach, instead of top down (from observation comes discoveries in physics, not the other way around). They started with an idea . . . hmmm lets play with the topological aspects of strings and try to solve the problem with Quantum gravity via a bottom up approach . . . then when that did not pan out (becuase it required vacuum energies WAAAY to high to reflect this reality) they then change it up and say that each string theory represents a different reality, not our own, then they come up with 10 dimensions, oh wait that doesn't work either becuase then it fails to represent our reality in a different way, lets add a 11th dimension, oh wait that doesn't work either dam that vacuum energy. Where is the empirical data that wants each string vibration to be a different particle: answer, that is arbitrary as well, it sounded nice and allows for lots of fun with math.

It reminds me of lawyers trying to find a way to get a bit of legislation approved, they shift the goal posts, they replace small pieces of the "theory" and hope that it sticks.

THAT is not how science has been done over the last 300 years that has built the standard model. If it does not work, its discarded. Its time to discard strings as means to explore physics.

If 11 dimensions explains neutrino mass, but then that model requires a vacuum energy 10X (or whatever other property our universe clearly does not have) times that which we find, it does not represent our reality. Its like a rubix cube where one side is perfect, but the rest is wrong. Well then its all wrong and you should reevaluate the premises used to arrive at that conclusion.

Personally I think a bottom up approach that takes a single property (strings) sets it arbitrarily and then tries to make the rest of the universe fit in is a broken approach.

http://www.math.columbia.edu/~woit/wordpress/

Saying our current understanding of the standard model doesn't answer all the questions we want, is different then saying that 11 dimensional math works to solve one problem, but requires a reality which we clearly do not live in. ie I have a problem with the leading line to that article.



There may end up being an infinite number of mathematical constructs that solve the neutrino problem but if the model they fit in does not describe our universe then its wrong.

Some scientist with CERN claim to have blown Einsteins E=mc2 theory out of the water. Apparently they have found Neutrinos that can travel faster than 3.00X10^8 m/s. This will be interesting to see what they have discovered if anything.

Even if this were the case it doesn't make his theory wrong. It just finds something that doesn't follow it.

Look at Ohm's Law. It is actually a Law but it applies to Ohmic devices. It doesn't apply to everything.

Well I think not. The basis for G.Reletivity is that light is a constant, and from that we get space-time warping. Without light as a constant the rest of the theory unravels very quickly.

What is rather spectacular IMHO, is that we physics geeks, and physicists all agree that when you have a mountain of evidence to back up a theory, including observational data reproduced over and over you do not take lightly the overturning of that.

Conversely taking the other side of that, you do not throw in with a theory that is not really a theory at all becuase it fails to make falsifiable predictions, ala string theory. Theories explain observations, they make sense of the reality we have in front of us, and provide insight into finding solutions. All of the various string theories fail to meet these basic criteria, and on its head should be seen in that light, however the marketing of this pseudo theory has been such to blind the pragmatic side of many a physics professional over the last 30 years.

The reality is that the standard model DOES meet these criteria, and MANY times various individuals have claimed to prove it cannot be an accurate model, only to fall short of really proving anything.

Your intransigence is showing.

Hardly. I have no dog in the race. String theory has made no predictions, and as of yet this finding has not been explained, ie it has not proved anything wrong. It has indicated, that there is a problem with the standard model. Lets give it time, as far as M-theory, it still fails to meet the minimum requirements of a theory. The standard model does make predictions, and they have been verified. This places it leagues above strings.

Even if the standard model is wrong, this does not make string theory right.

To me metal its quite interesting that you fail to see the failings of strings. Where as the standard model to me is just another set of ideas that explain observations, it appears M-theory is a pet ideology to you, one where you hold up its geniuses and use there names as an appeal to some kind of genius authority, when asked for predictive power we get excuses, and hand waving.

Its almost a religious zeal string proponents measure against. Its even so bad that you feel the need to belittle, and use pejoratives where I have NEVER done that with you.

Hardly. I have no dog in the race. String theory has made no predictions, and as of yet this finding has not been explained, ie it has not proved anything wrong. It has indicated, that there is a problem with the standard model. Lets give it time, as far as M-theory, it still fails to meet the minimum requirements of a theory. The standard model does make predictions, and they have been verified. This places it leagues above strings. If we made as many allowances for the standard model as strings have then we could be here to the end of time making excuses why the indication is not valid, or how to amend the standard model to make it work, or wave our hands and ask what the definition of a prediction really is . . . .

Even if the standard model is wrong, this does not make string theory right.

To me metal its quite interesting that you fail to see the failings of strings. Where as the standard model to me is just another set of ideas that explain observations, it appears M-theory is a pet ideology to you, one where you hold up its geniuses and use there names as an appeal to some kind of genius authority, when asked for predictive power we get excuses, and hand waving.

Its almost a religious zeal string proponents measure against. Its even so bad that you feel the need to belittle, and use pejoratives where I have NEVER done that with you. Science does not require such, in fact it tends to illuminate a lack of understanding.

Neutrino Findings Indicate Flaw In Standard Model
Physicists appear to have uncovered a flaw in the model that for the last 30 years has successfully explained the workings of the universe.

Their measurements indicate a surprising one percent discrepancy between predictions for the behavior of neutrinos and the way the elusive subatomic particles actually behave.

The findings, announced last week at Fermilab, the world's highest energy accelerator, could mean that an unknown force or undiscovered particle is influencing the neutrinos.

"One percent may not seem a big difference," says Kevin McFarland, assistant professor of physics and astronomy at the University of Rochester and team leader of the project, "but the measurement is so precise that the probability that the predictions are right, given our result, is only about one in 400."

McFarland and the members of his team slammed a 100 million watt beam of protons into a target to produce tens of billions of neutrinos. Working at Fermilab over the course of eight years, they observed millions of interactions of the highest energy, highest intensity neutrinos ever produced. Extremely precise experiments on other particles have spelled out exactly how neutrinos should behave, but to the experimenters' surprise, when they looked at neutrinos with comparable precision, neutrinos did not appear to fall into line with expectations.

"It might not sound like much, but the room full of physicists fell silent when we first revealed the result," said physicist Sam Zeller, a graduate student from Northwestern University and collaborator on the experiment.

The neutrino is one of the fundamental particles that make up our universe. Neutrinos carry no charge, unlike positively charged protons or negatively charged electrons, so the only thing that affects them is the "weak force" -- a force whose effects are usually only seen inside the nucleus of an atom. As a result, neutrinos rarely interact with anything, making them extremely difficult to detect.

The sun emits incomprehensibly vast numbers of neutrinos -- about 1,000 trillion pass through your body every second.

Physicists designed the NuTeV (Neutrinos at the Tevatron) experiment in order to observe the interactions of millions of the highest-energy, highest-intensity neutrinos ever produced.

Starting with a proton beam from Fermilab's Tevatron, the world's highest-energy particle accelerator, experimenters created a beam of neutrinos directed at a giant particle detector. The detector itself was a 700-ton sandwich of alternating slices of steel and detector. As the beam passed from the first to the last slice, one in a billion neutrinos collided with a target nucleus, breaking it apart.

After the collision with a nucleus, the neutrino could either remain a neutrino or turn into a muon, a particle that is a heavier cousin of the electron. When experimenters saw a nucleus break up, they knew a neutrino had interacted. If they saw a particle leaving the scene of the collision, they knew it was a muon. If they saw nothing leaving, they knew a neutrino (invisible to the detector's "eye") had come and gone.

The scientists measured the ratio of muons to neutrinos and compared it with the predicted values, which other experiments have verified to a part per thousand accuracy for other particles. A painstaking years-long analysis of the data revealed the unexpected discrepancy.

Neutrinos have surprised particle physicists before, but the new data have left the experimenters wondering if their neutrinos have felt a new force previously unobserved in nature, or if there is some hitherto undiscovered particle influencing neutrino interactions.

Physicists in the United States, Japan, and Europe are planning a next generation of neutrino experiments which may solve this newly uncovered puzzle -- or which may find even more puzzles. Other physicists, working at Fermilab or at CERN accelerators, could be observing previously unknown particles that may influence the neutrino.

McFarland has given a presentation on the measurement at Fermilab, and a paper describing the result has been submitted to Physical Review Letters.

In addition to the University of Rochester, the 45-member collaboration included physicists from the University of Cincinnati, Columbia University, Fermilab, Kansas State University, Northwestern University, the University of Oregon and the University of Pittsburgh.

The research was supported by the National Science Foundation, the U.S. Department of Energy and the Alfred P. Sloan Foundation.

Fermilab is operated by Universities Research Association, Inc. under a contract with the U.S. Department of Energy. - By Jonathan Sherwood

Conrad_73 most of the people who frequent this thread know what a scientific theory is.

i don't think that's the case at all from what i read here.