If you measure the redshift and blueshift of every galaxy, you can trace it back to a point. Interestingly, this point is not centered on us but is a few million light-years away, a minuscule fraction (under 0.1%) of the size of the observable Universe. However, it's crucial to understand the Big Bang as an event in time rather than a specific location in space.
Understanding the Big Bang and the expanding Universe can be challenging, even for astrophysicists. At the edge of what our telescopes can detect, galaxies are retreating so swiftly that their emitted light has been stretched significantly, up to twelve times their original wavelength. This effect is due to the Universe’s expansion and appears nearly uniform in all directions.
Does the variance in redshift, where one direction has a slightly higher redshift compared to its opposite, reveal the Big Bang's actual location? We can analyze redshift as a sign of light moving away and blueshift as light moving toward us. If the leftover light from the Big Bang shows more redshift in one direction and more blueshift in the opposite, could this indicate our relative position to the "origin point" of the Big Bang?
In astrophysics, this isn't a common approach, but it’s possible. Let’s explore the implications of such an analysis and discuss why it’s typically not pursued.
Observationally, the Universe shows a consistent relationship between a galaxy's light and its distance from us: the further away a galaxy is, the more its light is redshifted. This pattern is seen uniformly across the sky. The speed inferred from the redshift is directly proportional to the galaxy's distance from us.
This observation, first made in the 1920s, led cosmologists to conclude that the Universe is expanding. The farther an object, the quicker it appears to be moving away, a rule standing strong for nearly a century. However, slight directional differences exist: one direction shows a minor increase in redshift, while the opposite shows a slight increase in blueshift.
These differences make sense considering the Universe's non-uniformity, with gravitational variations affecting it. Dense regions, like galaxies and clusters, and sparse regions, like cosmic voids, create gravitational influences that move everything, including galaxies and structures like our Milky Way.
Because of these gravitational forces, it's challenging to define our exact motion relative to the Universe. However, there is a natural method to gain this understanding.
0 Comments