Physicists Must Accept That Some Things Are Unknowable (Synopsis) [Starts With A Bang]

“To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge.” –Nicolaus Copernicus

As we peel back the layers of information deeper and deeper into the Universe’s history, we uncover progressively more knowledge about how everything we know today came to be. The discovery of distant galaxies and their redshifts led to expanding Universe, which led to the Big Bang and the discovery of very early phases like the cosmic microwave background and big bang nucleosynthesis.

After the Universe’s atoms become neutral, not only did the photons cease scattering, all they do is redshift subject to the expanding spacetime they exist in, diluting as the Universe expands while losing energy as their wavelength continues to redshift. Image credit: E. Siegel, from his book, Beyond the Galaxy.

But before that, there was a period of cosmic inflation that left its mark on the Universe. What came before inflation, then? Did it always exist? Did it have a beginning? Or did it mark the rebirth of a cosmic cycle? Maddeningly, this information may forever be inaccessible to us, as the nature of inflation wipes all this information clean from our visible Universe.

Image credit: E. Siegel, with images derived from ESA/Planck and the DoE/NASA/ NSF interagency task force on CMB research. From his book, Beyond The Galaxy.

Go find out why some things are inherently unknowable on this special Sunday edition of Starts With A Bang!

from ScienceBlogs http://ift.tt/238mu2p

“To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge.” –Nicolaus Copernicus

As we peel back the layers of information deeper and deeper into the Universe’s history, we uncover progressively more knowledge about how everything we know today came to be. The discovery of distant galaxies and their redshifts led to expanding Universe, which led to the Big Bang and the discovery of very early phases like the cosmic microwave background and big bang nucleosynthesis.

After the Universe’s atoms become neutral, not only did the photons cease scattering, all they do is redshift subject to the expanding spacetime they exist in, diluting as the Universe expands while losing energy as their wavelength continues to redshift. Image credit: E. Siegel, from his book, Beyond the Galaxy.

But before that, there was a period of cosmic inflation that left its mark on the Universe. What came before inflation, then? Did it always exist? Did it have a beginning? Or did it mark the rebirth of a cosmic cycle? Maddeningly, this information may forever be inaccessible to us, as the nature of inflation wipes all this information clean from our visible Universe.

Image credit: E. Siegel, with images derived from ESA/Planck and the DoE/NASA/ NSF interagency task force on CMB research. From his book, Beyond The Galaxy.

Go find out why some things are inherently unknowable on this special Sunday edition of Starts With A Bang!

from ScienceBlogs http://ift.tt/238mu2p