# Neutrinos and black holes **URL:** \ **Category:** Factual Questions\ **Created:** [January 24, 2000, 12:15am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519 "2000-01-24T00:15:00Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 2, 2012, 3:22am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/41 "2012-10-02T03:22:51Z")
I did some additional reading and came upon texts from John Moffat, John Barrow, Andreas Albrecht, and Joao Magueijo. Do you think that they are all off with their theories then? It seems that in string theory variable speed of light is a common concept. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 2, 2012, 3:43am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/42 "2012-10-02T03:43:02Z")
Also change in the fine-structure constant could be explained by varying the speed of light and/or the electron charge… ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [October 2, 2012, 4:24am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/43 "2012-10-02T04:24:18Z")
> [@Gin\_Bell](#): > > I did some additional reading and came upon texts from John Moffat, John Barrow, Andreas Albrecht, and Joao Magueijo. Do you think that they are all off with their theories then? > > It seems that in string theory variable speed of light is a common concept. > [@Gin\_Bell](#): > > Also change in the fine-structure constant could be explained by varying the speed of light and/or the electron charge… IANAPhysicist, so anything I add is coming from a thoroughly interested, yet alas, a layman. When talking about VSL theories, it brings up a lot of questions, such as: are the ratios between other fundamental constants like the Planck length and the gravitational constant kept the same/remain normalized, etc? It’s a whole 'nuther can of worms and starting a new thread specifically about VSL in GQ or GD might be warranted if you’d like to persue this issue as you’d probably attract the right posters suited better toward the questions you’re asking. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 2, 2012, 4:45am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/44 "2012-10-02T04:45:27Z")
Thanks I will. I have been reading a lot since I posted few days ago and am slowly advancing 🆒 ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 2, 2012, 6:22pm UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/45 "2012-10-02T18:22:19Z")
> [@cmyk](#): > > IANAPhysicist, so anything I add is coming from a thoroughly interested, yet alas, a layman.. That is so cool!! I always wanted to meet a physicist. People like yourself are awesome to listen to 🙂 Since you understand all of this much better, could you possible share your vision on “consciousness”? I haven’t yet found a satisfactory definition. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [October 2, 2012, 10:00pm UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/46 "2012-10-02T22:00:55Z")
> [@Gin\_Bell](#): > > That is so cool!! I always wanted to meet a physicist. People like yourself are awesome to listen to 🙂 IANA is an acronym for “I am NOT a…” So cymk is saying he is not a physicist. Which is also what “layman” means. > [@](#): > > Since you understand all of this much better, could you possible share your vision on “consciousness”? I haven’t yet found a satisfactory definition. You should search for the many previous threads for “consciousness.” Nobody has any answers at all, but we manage to argue it at length regardless. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 2, 2012, 10:25pm UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/47 "2012-10-02T22:25:08Z")
It’s not really even meaningful to ask whether c changes, since you’d have to specify units, which means that you’d need to specify standards by which to define those units, and then you could just as well argue that it’s really your standards that are changing, not c. All you can really meaningfully talk about changing are the dimensionless constants, such as the fine structure constant. If you wanted to talk about whether a speed is changing, what you’d do would be to take the ratio of that speed to c, and see whether that ratio is changing… But this is clearly useless when talking about c itself. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [October 2, 2012, 10:51pm UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/48 "2012-10-02T22:51:27Z")
> [@Exapno\_Mapcase](#): > > IANA is an acronym for “I am NOT a…” So cymk is saying he is not a physicist. Which is also what “layman” means. > You should search for the many previous threads for “consciousness.” Nobody has any answers at all, but we manage to argue it at length regardless. Not to mention, there are plenty of _real-live_ physicists/astronomers aboard; **Chronos,** for one—from whom (et al) I’ve learned much from on these topics in my 11+ years here. However, I do love a good discussion on the nature of consciousness (as I’m far more comfortable waxing philosophical than anything else), but this thread ain’t the place. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 12:12am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/49 "2012-10-03T00:12:30Z")
Do you think consciousness is present at quantum level? The reason I ask here is because I’d really appreciate to hear from someone with insight in physics and feel for formulas. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 12:47am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/50 "2012-10-03T00:47:34Z")
At least, we now know that God is particulate, with a half-life in the low billionths of a second. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 3, 2012, 12:52am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/51 "2012-10-03T00:52:24Z")
> [@douglips](#): > > …[li]Since neutron stars are 1.1 x 10[sup]14[/sup] more dense, a neutrino will encounter the same amount of material in 1 light-year of lead in approximately 85 meters of neutron star…[/li] > [@Chronos](#): > > And to definitively answer the OP: Neutrinos do pass through neutron stars mostly unscathed (perhaps a tenth of a percent of them would interact, but not much more than that)… Are these two statements mutually supportive? ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 3, 2012, 12:55am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/52 "2012-10-03T00:55:38Z")
> [@Ludovic](#): > > Braaanes. Mmmm-s. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [October 3, 2012, 12:58am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/53 "2012-10-03T00:58:35Z")
> [@Leo\_Bloom](#): > > Are these two statements mutually supportive? If it’s true what Wikipedia says, > [@](#): > > Neutrinos are omnipresent in nature such that in just one second, tens of billions of them “pass through every square centimetre of our bodies without us ever noticing.”[3] , then light-years of lead might not be thick enough to stop the average neutrino, considering that we have to watch much more than a centimeter of neutrino detection fluid for longer than a second to see even one neutrino collision out of trillions that pass through it. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 1:54am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/54 "2012-10-03T01:54:15Z")
Its hard to imagine that something with mass can pass through a star… ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [October 3, 2012, 2:28am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/55 "2012-10-03T02:28:46Z")
Holy crap! I think I just felt a neutrino. Kinda tingles… ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 2:32am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/56 "2012-10-03T02:32:56Z")
Neutrinos?? It;s all witchcraft I say! Time for another mushroom and then of to bed… ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 3, 2012, 2:45am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/57 "2012-10-03T02:45:27Z")
> [@](#): > > I think I just felt a neutrino. Kinda tingles… You joke, but the estimates are that one or two people on the planet “saw” neutrinos from Supernova 1987a. That is to say, that for those people, a neutrino would have interacted with the matter in their eyes in such a way as to produce a visible flash of light. Of course, there would be no way to find such people, or to be sure that that was the cause of any flash they might have seen. **Gin Bell** , I’m not sure why you’d be eager to ask a physicist in particular about consciousness, since consciousness doesn’t really have anything to do with physics. You’d be much better off asking a psychologist or a philosopher. ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 2:49am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/58 "2012-10-03T02:49:58Z")
> [@Chronos](#): > > **Gin Bell** , I’m not sure why you’d be eager to ask a physicist in particular about consciousness, since consciousness doesn’t really have anything to do with physics. What a wonderful way to get an unbiased opinion 🙂 ---
**Author:** ![Gin\_Bell](https://avatars.discourse-cdn.com/v4/letter/g/4af34b/32.png) [@Gin\_Bell](https://boards.straightdope.com/u/Gin_Bell)\ **Post date:** [October 3, 2012, 2:52am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/59 "2012-10-03T02:52:51Z")
> [@Chronos](#): > > That is to say, that for those people, a neutrino would have interacted with the matter in their eyes in such a way as to produce a visible flash of light. It takes at least the size of 5 photons to see something and that much would be so small it is just considered noise. I highly a neutrino was ever seen with the naked eye. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [October 3, 2012, 2:57am UTC](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519/60 "2012-10-03T02:57:30Z")
> [@Chronos](#): > > You joke, but the estimates are that one or two people on the planet “saw” neutrinos from Supernova 1987a. That is to say, that for those people, a neutrino would have interacted with the matter in their eyes in such a way as to produce a visible flash of light. Of course, there would be no way to find such people, or to be sure that that was the cause of any flash they might have seen. Okay, now I’m just really preoccupied about seeing any neutrino flashes. One day, my opthamologist is going to reprimand me for not seeing him earlier because of retinal detachment, and my only lame excuse will be, “I thought I was detecting neutrinos!” If my opthamologist is cool, he’ll nod in full understanding. Then I’ll have to find a guide dog. And sob in utter darkness. Unless a neutrino hits a neuron in my occipital lobe. [Previous page](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519.md?page=2) [Next page](https://boards.straightdope.com/t/neutrinos-and-black-holes/6519.md?page=4)