For by him were all things created, that are in heaven, and that are in earth, visible and invisible,.... Colossians 1:16
"A recent news item reported the discovery of neutrinos from just one second after the big bang. Such a thing would be big news indeed, but could such a thing be true? Alas, examination shows that the news headline isn’t exactly accurate.
Neutrinos of this energy would be very difficult, if not impossible, to detect.
Therefore, the recent news stories, such as this one with the bold title “Earliest Signal Ever: Scientists Find Relic Neutrinos From 1 Second After the Big Bang,” were quite a surprise. Even more bold was this statement in this news account:
Rather, what was reported was indirect evidence of those neutrinos. Even after their decoupling, the gravitational effect of primordial neutrinos would have affected the density distribution of matter in the early big bang universe.
This hypothetically would show up as a phase shift in acoustic oscillations in the CMB. Indeed, this supposedly was discovered a few years ago. Hence, this earlier study amounted to the first indirect detection of a possible effect of the CNB.
So, what was discovered this time?
The temperature fluctuations in the CMB supposedly were caused by density fluctuations in the early universe that eventually gave rise to the structure that we see in the universe today (the distribution of galaxies).
Therefore, any effects of primordial neutrinos are expected to show up in the structure of the universe observable today. For nearly two decades the Sloan Digital Sky Survey (SDSS) has been collecting data on the distribution of galaxies, revealing the structure of the universe.
--The current study modeled the power spectrum of the most recent SDSS data release in terms of two parameters - α, and β -, that would describe the effect of primordial neutrinos.
The study yielded constraints on the values of α and β that are consistent with the CNB. Hence, all the excitement over this result. But this amounts to a second, indirect detection, not direct detection, of the CNB, as the headlines implied (or in some cases claimed).
First, keep in mind that this is indirect evidence of the CNB, not direct detection. Given the extremely low energy of these neutrinos today, it’s not likely that they ever will be detected.
Second, this is a statistical study. The researchers claim a 95% confidence that they have found this indirect signal. However, such highly confident signals have been heralded in the past, only to be walked back later.
One example was the announcement of the first evidence for cosmic inflation five years ago. That one lasted only a few months. Third, this result is highly model-dependent. If one changes the model, the result changes. And if the model is wrong, the result isn’t likely to be true anyway."
AIG
"A recent news item reported the discovery of neutrinos from just one second after the big bang. Such a thing would be big news indeed, but could such a thing be true? Alas, examination shows that the news headline isn’t exactly accurate.
Neutrinos of this energy would be very difficult, if not impossible, to detect.
Therefore, the recent news stories, such as this one with the bold title “Earliest Signal Ever: Scientists Find Relic Neutrinos From 1 Second After the Big Bang,” were quite a surprise. Even more bold was this statement in this news account:
The data is in, and the results are incontrovertible: the cosmic neutrino background is real, and agrees with the Big Bang.
It all sounds very convincing, that physicists had actually detected neutrinos in the CNB, coming from one second after the big bang. Except that they didn’t.
This hypothetically would show up as a phase shift in acoustic oscillations in the CMB. Indeed, this supposedly was discovered a few years ago. Hence, this earlier study amounted to the first indirect detection of a possible effect of the CNB.
So, what was discovered this time?
The temperature fluctuations in the CMB supposedly were caused by density fluctuations in the early universe that eventually gave rise to the structure that we see in the universe today (the distribution of galaxies).
Therefore, any effects of primordial neutrinos are expected to show up in the structure of the universe observable today. For nearly two decades the Sloan Digital Sky Survey (SDSS) has been collecting data on the distribution of galaxies, revealing the structure of the universe.
--The current study modeled the power spectrum of the most recent SDSS data release in terms of two parameters - α, and β -, that would describe the effect of primordial neutrinos.
The study yielded constraints on the values of α and β that are consistent with the CNB. Hence, all the excitement over this result. But this amounts to a second, indirect detection, not direct detection, of the CNB, as the headlines implied (or in some cases claimed).
First, keep in mind that this is indirect evidence of the CNB, not direct detection. Given the extremely low energy of these neutrinos today, it’s not likely that they ever will be detected.
Second, this is a statistical study. The researchers claim a 95% confidence that they have found this indirect signal. However, such highly confident signals have been heralded in the past, only to be walked back later.
One example was the announcement of the first evidence for cosmic inflation five years ago. That one lasted only a few months. Third, this result is highly model-dependent. If one changes the model, the result changes. And if the model is wrong, the result isn’t likely to be true anyway."
AIG
