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Fraser
2007-Apr-17, 03:50 AM
Trillions of neutrinos are produced in our Sun through its nuclear reactions. These particles stream out at nearly the speed of light, and pass right through any matter they encounter. ...

Read the full blog entry (http://www.universetoday.com/2007/04/16/podcast-the-search-for-neutrinos/)

trinitree88
2007-Apr-17, 04:19 PM
Trillions of neutrinos are produced in our Sun through its nuclear reactions. These particles stream out at nearly the speed of light, and pass right through any matter they encounter. ...

Read the full blog entry (http://www.universetoday.com/2007/04/16/podcast-the-search-for-neutrinos/)
//

Fraser. There is as yet no definitive evidence of neutrino masses. Experimental results only set upper bounds on what possible masses might be.(you can check with Eta C and the Particle Data Group). All neutrino mixing or oscillation observations have involved matter path lengths, the atmosphere, the outer layers of the sun, the Earth itself, miles of crust..etc. This does not require mass in the neutrinos as it is supplied by the intervening mass wherein the mixing takes place (MSW matter oscillations).
So the original fermionic neutrino, massless and traveling exactly at c, like it's cousin the photon remains a valid physical paradigm until definitively disproven. Massive neutrinos will mean abandoning conservation of electron, muon, and tau family number laws because of SR, and that is something that no particle experimentalist has ever seen. Not one experiment, not one run, not one event, in trillions of events.So we can eliminate the "stream out at nearly the speed of light" expression, and replace it without the word nearly. :think: Pete.

kashi
2007-Apr-18, 05:53 AM
The device looks a lot like the Xindi weapon in season 3 of Star Trek Enterprise...

Jerry
2007-Apr-18, 06:13 PM
//
Not one experiment, not one run, not one event, in trillions of events.So we can eliminate the "stream out at nearly the speed of light" expression, and replace it without the word nearly. :think: Pete.

Thank you!

What I am still wondering (the podcast died on me midstream), is if three flavors of neutrinos have been observed 'streaming' from the sun - is the shortage of electron(?) neutrinos observed as an excess of other flavors?

There are other possible solutions to the neutrino shortage that don't necessarily require new physics - the internal magnetic fields in the sun could preferentially align the reactants before fussion, for example...

trinitree88
2007-Apr-18, 06:38 PM
Thank you!

What I am still wondering (the podcast died on me midstream), is if three flavors of neutrinos have been observed 'streaming' from the sun - is the shortage of electron(?) neutrinos observed as an excess of other flavors?

There are other possible solutions to the neutrino shortage that don't necessarily require new physics - the internal magnetic fields in the sun could preferentially align the reactants before fussion, for example...

Jerry. You're welcome. The latest from SNO is here:
http://www.sno.phy.queensu.ca/sno/neutrino.html

I was responding mostly to Fraser's wording. As yet the data do not rule out massless neutrinos, they only limit upper bounds on possible masses. Eta C has been good about this:http://pdg.lbl.gov/
I look forward to their continued work...and yes they see more of the other types.Pete.

rpdelgado
2007-Apr-19, 10:24 PM
How can you have 22 ly of lead ?

what do you mean ? How can you have 22 ly of lead in any direction. Traveling 22ly in a solid lead-only enviroment ?!

trinitree88
2007-Apr-19, 11:35 PM
How can you have 22 ly of lead ?

what do you mean ? How can you have 22 ly of lead in any direction. Traveling 22ly in a solid lead-only enviroment ?!


rpdelgado;971583. Technically you can't. It's a numerical order of magnitude for stopping all the neutrinos. They have a cross-section for interaction that is extremely low. The probability of interaction in particle physics is defined as a product of flux..phi...and cross-section...sigma. P(x) = sigma * phi,..where P(x) is the probability of interaction. The cross-sections for some interactions measured in surface area (like radar cross-sections) were tiny...~ 10-44 sq. cm....that's tiny. So, it's as if there's nothing there, and you need a long matter length to create an interaction.I believe that that specific number refers to absorption, not neutral current scattering. pete.

RussT
2007-Apr-22, 09:19 PM
Do you think it is 'possible' that the Neutrino Sea is responsible for the Shapiro Effect?

trinitree88
2007-Apr-23, 01:17 AM
Do you think it is 'possible' that the Neutrino Sea is responsible for the Shapiro Effect?

RussT. As the changes in the neutrino sea flux mirror the geodetics of GR, I'm going to say yes. (You know I like sticking my head in the science guillotine). My knowledge of GR is far too qualitative for me to make a numerical prediction here, but I will say qualitatively, if the suspected solar 22 year sunspot/ neutrino gradient cycle discussed with suntrack2 earlier today turns out to be true....then the observed Shapiro Effect on the radar return from Venus should show a change, unfortunately the clock timing the effect should,too,as it is in the same changed sea and may be entirely compensating. The geodetic curvature that lengthens the photon path for the radar wave also slows clocks.
To prove the point, one might analyze an independent neutrino flux gradient. However, a signal delay from a distant satellite observed during the prompt neutrino burst of SN1987a would be argued by a general relativist as having been due to the gravitational waves seen at Rome and Maryland in the bar detectors. But, to do that, they would then have to say that I was correct. :shifty: So, if you find such a piece of data in the JPL archives or some such...let me know. :D Thanks. pete.

RussT
2007-Apr-23, 08:35 AM
As the changes in the neutrino sea flux mirror the geodetics of GR, I'm going to say yes.

Well, that makes two of us, but for very different reasons I am sure. One of which, is that this would and does mean that they do have an infintesimal mass.

As for the predicted gravitational waves, I think it far more likely, since they do have an infintesimal mass, that they (the ones coming from all directions) 'smooth out' any 'event' that the waves could be coming from, long before they ever reach us.

btw, my head has been in the guillotine from the beginning, since what I have found goes directly against ALL the Laws of Thermodynamics, right from the get-go:D The Universe is working as an 'open system', BUT 'science' has ONLY investigated a 'closed system'.

RussT
2007-Apr-24, 09:04 AM
RussT. As the changes in the neutrino sea flux mirror the geodetics of GR, I'm going to say yes.

Okay, let me go one step farther then.:D

Do you think that it is 'possible' that the Neutrino Sea 'could' be the 'same thing' as the Cold Dark Matter?

In other words, Neutrinos are Hot DM and DM is actually Cold DM. So is it possible that these are really the same thing and they have only given them these designations because of 'where' they are 'seeing' them?

Jerry
2007-Apr-24, 04:12 PM
It is looks like the answer is no:

http://www.astro.princeton.edu/~dns/MAP/Bahcall/node6.html

There are several astronomical problems for neutrino dark matter models. Because cosmic background neutrinos have a Fermi-Dirac distribution, they have a maximum phase-space density, which implies a maximum space density [69]. Dwarf irregular galaxies [17] have very high dark matter densities and dwarf spheroidals [28] have even higher dark matter densities: neutrinos can not be the dark matter in these systems. So, if neutrinos are the dark matter in our Galaxy, then there is a need for a second type of dark matter for low mass galaxies [28]. Neutrino plus baryon models have a difficult time forming galaxies early enough and these models predict galaxy clustering properties significantly different from those observed in our universe.
It is my understanding that we should be able to statistically track neutrinos winging through local space in patterns consistent with a CDM halo.

RussT
2007-Apr-26, 09:59 PM
Okay, here's the deal.

This is the crux of the Unification of GR and QFT!!!

When mainstream introduced Non-baryonic DM/Exotic Matter as the possible answer to the 'extra gravity' needed to explain galaxy rotation curves and cluster dynamics, THIS is 'one' of the things that is RIGHT!

BUT, just the fact that it exists! There is this 'extra gravity' in our universe!

NOW, the fact that it exists in galaxies and clusters is true...that 'extra gravity MUST be there, and just its existence is NOT Big Bang Theory dependent, but if it is not there, everything falls apart IE; stars fly out of galaxies, galaxies fly out of clusters, BUT how they are 'seeing'/defining it is the problem.

GR/Big Bang 'see'/define it as 'slow'/massive particles, so they can form dark matter halos in the early promordial universe for the supposedly already made Hydrogen/Helium to 'fall into', while QM defines Neutrinos as the ? that goes right through baryonic matter, with anti Neutrinos for each of the electron/protron/neutron particles, with the Neutrinos being made in all the Stars!

When GR and QM 'see'/define the "Exotic Matter" the same way, THEN GR and QM will be unified. BUT, that means that there needs to be a change to BOTH GR and QM and the single reason this cannot be found is that the only "Legal" solutions are the ones that conform to the FLRW universe(s)!

SO, Jerry, all your (and some others) statements about GR needs to be thrown out, is simply IMHO, the very difficult exercise of understanding what is wrong with the Big Bang, and then what needs to be changed in GR to get to what is right.

AND, That one thing is simply, That the SMBH's are part of "Open Systems" so that the "Exotic Matter"/Non-baryonic DM can come into our universe at the Voids and leave our universe through OUR SMBH's.