The results from the BICEP2 experiment was such a major a deal for Physics and Cosmology this week that the news spread pretty far into the mainstream, although expectedly in a rather confused way. So you may wonder "what's the big fuss?"
As usual, Hank does a better job breaking it down quickly.
I'll throw in my $0.02 since this is ever so slightly in my wheelhouse considering that this is a precision rifle forum. The results basically rocked the foundation of the Physics and Cosmology (not makeup and hairdos, but the study of the origin, evolution and fate of the Universe) communities because it's kind of a triple-whammy of breakthroughs.
First, it's more evidence for the existence of Gravitational Waves. Why is that important? Of all the many predictions of Einstein's extremely successful theory of General Relativity, the existence of gravitational waves is the last one yet to be confirmed. They've been seen indirectly before, but this observation better fits predictions based on the CMB (Cosmic Microwave Background) and how it would be affected by an initial rapid expansion of the very early Universe.
Second, it's the first direct evidence of Inflation, a theory that explains how the early Universe went through a rapid expansionary period between the very beginning and where the Big Bang model picks up. The Big Bang model has been supported by more and more evidence over the last fifty years, but there have always been peculiarities that bothered Cosmologists. In particular, observation of the CMB shows that the distribution of matter/energy is incredibly smooth and homogeneous, which doesn't make sense when you extrapolate our understanding of Physics from the start to where the Universe has expanded to over 13.8 billion years. To figure out a way to explain why that might be, Alan Guth came up with the theory of Inflation, which is a mathematical model allowing for the Universe in the first 1 x 10[SUP]-34[/SUP] seconds (0.00000000000000000000000000000000001) of its existence to go through a short, rapid expansion. This process creates very smooth initial conditions for the Universe consistent with the observational data. The BICEP2 experiment looked at the polarization of the microwaves in the CMB and how they were distorted by gravitational waves consistent with Guth (and Linde's) mathematical models for Inflation.
Third, this new evidence for Gravitational Waves and Inflation suggests that there is very likely a quantum component to Gravity! This is a big deal because the two physics models that we reliably use are General Relativity (explains the motion of the very large) and Quantum Mechanics (explains the motion of the very small), however there is no crossover between the two and no way to join them into a Grand Unified Theory. The key is Gravity, which General Relativity explains to high precision as a natural curvature to space/time in the presence of mass/energy. But there is still no working component for gravity in Quantum Mechanics and this is a huge problem. There have been many proposals, but none of them yet have been confirmed by experimental data. Part of the problem is that compared to the three other forces in Physics (electromagnetism, strong nuclear & weak nuclear), gravity is insanely weak so building a particle accelerator powerful enough to detect its force carrier particles will never be practical. Thankfully, Inflation by its very definition relies on Quantum Mechanics and because there is now evidence for it and the gravitational waves it predicts, that indirectly means that there is in fact a quantum mechanical component to gravity. So in other words, we don't know exactly where the land nav point is on the map, but at least we know what grid square it's in.
On a side note - This is a science topic, not a religious topic - please keep it that way.
As usual, Hank does a better job breaking it down quickly.
I'll throw in my $0.02 since this is ever so slightly in my wheelhouse considering that this is a precision rifle forum. The results basically rocked the foundation of the Physics and Cosmology (not makeup and hairdos, but the study of the origin, evolution and fate of the Universe) communities because it's kind of a triple-whammy of breakthroughs.
First, it's more evidence for the existence of Gravitational Waves. Why is that important? Of all the many predictions of Einstein's extremely successful theory of General Relativity, the existence of gravitational waves is the last one yet to be confirmed. They've been seen indirectly before, but this observation better fits predictions based on the CMB (Cosmic Microwave Background) and how it would be affected by an initial rapid expansion of the very early Universe.
Second, it's the first direct evidence of Inflation, a theory that explains how the early Universe went through a rapid expansionary period between the very beginning and where the Big Bang model picks up. The Big Bang model has been supported by more and more evidence over the last fifty years, but there have always been peculiarities that bothered Cosmologists. In particular, observation of the CMB shows that the distribution of matter/energy is incredibly smooth and homogeneous, which doesn't make sense when you extrapolate our understanding of Physics from the start to where the Universe has expanded to over 13.8 billion years. To figure out a way to explain why that might be, Alan Guth came up with the theory of Inflation, which is a mathematical model allowing for the Universe in the first 1 x 10[SUP]-34[/SUP] seconds (0.00000000000000000000000000000000001) of its existence to go through a short, rapid expansion. This process creates very smooth initial conditions for the Universe consistent with the observational data. The BICEP2 experiment looked at the polarization of the microwaves in the CMB and how they were distorted by gravitational waves consistent with Guth (and Linde's) mathematical models for Inflation.
Third, this new evidence for Gravitational Waves and Inflation suggests that there is very likely a quantum component to Gravity! This is a big deal because the two physics models that we reliably use are General Relativity (explains the motion of the very large) and Quantum Mechanics (explains the motion of the very small), however there is no crossover between the two and no way to join them into a Grand Unified Theory. The key is Gravity, which General Relativity explains to high precision as a natural curvature to space/time in the presence of mass/energy. But there is still no working component for gravity in Quantum Mechanics and this is a huge problem. There have been many proposals, but none of them yet have been confirmed by experimental data. Part of the problem is that compared to the three other forces in Physics (electromagnetism, strong nuclear & weak nuclear), gravity is insanely weak so building a particle accelerator powerful enough to detect its force carrier particles will never be practical. Thankfully, Inflation by its very definition relies on Quantum Mechanics and because there is now evidence for it and the gravitational waves it predicts, that indirectly means that there is in fact a quantum mechanical component to gravity. So in other words, we don't know exactly where the land nav point is on the map, but at least we know what grid square it's in.
On a side note - This is a science topic, not a religious topic - please keep it that way.
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