Faster than a speeding bullet...

[Greg Anos]

I follow the C.P.Snow metastructure for science.

You can't prove thing to be true, just false. Once you find something to be false,,you take all the old facts the new disproving fact, and create a new theory, and repeat the process. Truth keep getting constrained into a smaller and smaller locus, but never actual "proven".

As to whether C is the absolute speed limit, you have to explain to me why a vacuum has permittivity and permeability first. (See Maxwell's equations.)

Personally, I believe that every "constant" is merely the "answer" for another layer of complexity.

[beppe]

Originally Posted by Salgueiros

If you are a scientist, then why do you say silly things about things you do not know? Science is not "guessing" or "hinting" or "feeling" or personal opinions. What kind of science do you do?

What did I say that you judge silly? The fact that i am a scientist, or not, what I know or what I do not know, of which you are in the complete absence of information, except that I am not a specialist, what has that to do with the silliness that you attribute to me? Please, be kind enough to explain.

[Dulin's Books]

lets remember that the focus of the study was not the possibility of superluminal neutrinos. they were studying neutrino oscillation and this is a data point they discovered along the way they can not explain.

thats pretty amazing

Originally Posted by beppe

It is not enormously faster. Just a bit. A tiny bit in terms of everyday life.

its 18 meters at these speeds and distance.

at this much faster than C it would mean that neutrinos from SN1987A would have arrived some time in 1983.

Originally Posted by bhartman36

I'm not a scientist of any kind, but I've always thought that no science w What we know about physics beaks down inside black holes (e.g., yielding a lot of infinity values), so it's clear we have something wrong with how we see the universe.

or the inside of a blackhole is a different universe/dimension with its own physical laws.

lets say that C hasnt been violated. then that means the neutrinos somehow covered 18 meters in an instant. that outcome would be just as astonishing.

[beppe]

Originally Posted by Dulin's Books

at this much faster than C it would mean that neutrinos from SN1987A would have arrived some time in 1983.

SN 1987A was a supernova in the outskirts of the Tarantula Nebula in the Large Magellanic Cloud, a nearby dwarf galaxy. It occurred approximately 51.4 kiloparsecs from Earth, approximately 168,000 light-years.... The light from the supernova reached Earth on February 23, 1987.

I am so sorry, but I fail to see the reasons of being astonished by 1987-1983 = 4 over approximately 168,000. That is of 18 over 750,000.

[Dulin's Books]

because the known neutrinos detected that are associated with SN1987A arrived just 3 hours before the light. the fact that they arrived at all earlier is reasoned to be because they are actually emitted earlier in the process.

you seem to be of the opinion that the difference is miniscule. the difference between 3 hours and 4 years is hardly miniscule

[beppe]

Originally Posted by Dulin's Books

because the known neutrinos detected that are associated with SN1987A arrived just 3 hours before the light. the fact that they arrived at all earlier is reasoned to be because they are actually emitted earlier in the process.

you seem to be of the opinion that the difference is miniscule. the difference between 3 hours and 4 years is hardly miniscule

in terms of everyday life it is indeed. That what I said.

10 to the minus 5 is 50 db: you would not perceive a whisper 50 db lower than whatever you are listening to.

yes, they arrived earlier. But maybe they arrived 3 years earlier and nobody was looking for them. Long distance experiments are quite tricky. Also the light getting here had quite a history of its own. Unfathomable. Passing through every sort of unknown effects. Everything about nature is tricky.

[Manichean]

Speaking as a physicist, I'm pretty sure they really measured what they say they measured. Where the difference in times really comes from is another guess, though. I'd say the most probable explanation is that they overlooked some source of error. Looking at the paper, it can pretty much be summarized as "Huh. That's weird, anyone else seeing this?". It's being blown totally out of proportion in the media, if you ask me, which is a source of mild amusement, ("OMG EINSTEIN WAS WRONG!!! WARP SPEED HERE WE COME!" ), but still... I'm not seeing a flaw in relativity yet, the supernovae, for example, have already been quoted, I'm seeing an unexplained measurement.

Originally Posted by beppe

yes, they arrived earlier. But maybe they arrived 3 years earlier and nobody was looking for them.

Essentially, you can tell by the intensity of the neutrino emission from a supernova when they were emitted. So I'm pretty certain that they only moved as fast as they should have.
As far as the light emission from a supernova goes: If one can observe the supernova, then one can also observe what's in the path of the light. Thus, you can know how light is going to disperse.

[beppe]

Originally Posted by Manichean

Speaking as a physicist, I'm pretty sure they really measured what they say they measured. Where the difference in times really comes from is another guess, though. I'd say the most probable explanation is that they overlooked some source of error. Looking at the paper, it can pretty much be summarized as "Huh. That's weird, anyone else seeing this?". It's being blown totally out of proportion in the media, if you ask me, which is a source of mild amusement, ("OMG EINSTEIN WAS WRONG!!! WARP SPEED HERE WE COME!" ), but still... I'm not seeing a flaw in relativity yet, the supernovae, for example, have already been quoted, I'm seeing an unexplained measurement.


Essentially, you can tell by the intensity of the neutrino emission from a supernova when they were emitted. So I'm pretty certain that they only moved as fast as they should have.
As far as the light emission from a supernova goes: If one can observe the supernova, then one can also observe what's in the path of the light. Thus, you can know how light is going to disperse.

if it were so easy there would be no need for the complications of tomography. The most accurate thing one can do is radiative transfer and that's pretty rough and inaccurate. (speaking as a specialist).

The neutrino people go to conferences (there was one in Athens this year) and they know each other personally so there is no real need for what you say. i tend to lean on my b) interpretation.

[Manichean]

Originally Posted by beppe

if it were so easy there would be no need for the complications of tomography.

I didn't say it was easy. But one can tell relatively well how light is going to arrive from a given point in space, if you can observe what lies between there and here.

[beppe]

Originally Posted by Manichean

I didn't say it was easy. But one can tell relatively well how light is going to arrive from a given point in space, if you can observe what lies between there and here.

I am so sorry, I edited my previous post in a rather improper way.

What happens between here and there cannot be corrected if you do not know where it happened. Only a tomographic approach gives you that, including radar in it, in a generalized sense. For doing that the intensity alone is not sufficient.

[HarryT]

Originally Posted by Manichean

I didn't say it was easy. But one can tell relatively well how light is going to arrive from a given point in space, if you can observe what lies between there and here.

It's normally of course done the other way around: one can investigate the physics of the interstellar medium by observing what happens to light passing through it.

[Manichean]

Originally Posted by beppe

The neutrino people go to conferences (there was one in Athens this year) and they know each other personally so there is no real need for what you say. i tend to lean on my b) interpretation.

By that logic, all scientific papers are useless. Every field has conferences.
Also, did you actually look at the paper? That's really what it says.

Originally Posted by HarryT

It's normally of course done the other way around: one can investigate the physics of the interstellar medium by observing what happens to light passing through it.

Yes, I know. You can get the light-transmitting properties for a certain region of space by observing stars in that region. You'll get depth resolution by observing stars at different distances. Thus, you know how light propagates there. If a supernova then occurs there, you can predict how light is going to transmit through that region.

[beppe]

To know how light is dispersed you must know what it was when was emitted. That you do not know except by assuming that it has a spectrum similar to something else. You can estimate radial velocity of the source by the shift of lines, but not much more than that. Do you think that an effect of -50 dB could be resolvable with all those approximations and assumptions?

[Manichean]

Originally Posted by beppe

To know how light is dispersed you must know what it was when was emitted.

But you do know that. The extinction lines in a star spectrum have pretty narrow and well-defined wavelengths, so you'll know how the spectrum was shifted in transfer. Knowing the theory of stellar evolution, you'll know which kind of spectrum to expect. So, you do know what's been emitted.

Do you think that an effect of -50 dB could be resolvable with all those approximations and assumptions?

The effect we're talking about here was measured under wholly different circumstances. Keep in mind that we're not seeing faster neutrinos from supernovae, but only in the measurements done at CERN and Gran Sasso.

[Soldim]

Finally I had time the read the Cosmic Variance entry.

Evidently, I had read about the Supernova 1987A evidence, where neutrino's did not travel faster than c, however they had something to add to that:

More relevant is the fact that we have completely independent indications that neutrinos do travel at the speed of light, from Supernova 1987A. If the OPERA results are naively taken at face value, the SN 87A should have arrived a couple of years before we saw the explosion using good old-fashioned photons. But perhaps we should resist being naive; the SN 87A events were electron neutrinos, not muon neutrinos, and they were at substantially lower energies. If neutrinos do violate the light barrier, it’s completely consistent to imagine that they do so in an energy-dependent way, so the comparison is subtle.

Which, I guess doesn't help settling the debate for now