This was before he came up with his famous theory of general relativity, which we will discuss later on.

At that time, most scientists believed that the universe consisted of an infinite number of stars and galaxies spread out in all directions. But Einstein’s static model proposed a different idea: that the universe was actually finite and had a definite shape. This was a radical departure from conventional wisdom at the time, but it turned out to be wrong for several reasons.

First, Einstein’s theory did not take into account the fact that light travels at a constant speed in all directions. As a result, his model predicted that there should be no such thing as redshift the phenomenon where light from distant galaxies appears shifted towards longer wavelengths due to their motion away from us. But this was not observed in practice, and it became clear that Einstein’s theory needed some adjustments.

Secondly, Einstein’s model did not account for the fact that gravity is a force that acts over long distances. This meant that there should be no such thing as dark matter the mysterious substance that makes up most of the universe but cannot be detected directly. But this was also not observed in practice, and it became clear that Einstein’s theory needed some adjustments.

Finally, Einstein’s model did not take into account the fact that space-time is curved by massive objects like stars and galaxies. This meant that there should be no such thing as black holes the regions of space where gravity is so strong that nothing can escape. But this was also not observed in practice, and it became clear that Einstein’s theory needed some adjustments.

So what did Einstein do to fix these problems? Well, he came up with a new theory called general relativity, which took into account all of the above factors and more. This theory predicted that space-time is not just a flat surface like a piece of paper or a tabletop it’s actually curved by massive objects like stars and galaxies. And this curvature can have some pretty interesting effects on light and other forms of radiation, as we will see in the next section.

But before we get into that, let’s take a closer look at Einstein’s static model and why it was wrong. As you may recall from our previous article, this theory proposed that the universe had a definite shape either spherical or flat depending on whether there was enough matter to create a “critical density” of about 10-26 kg/m3.

However, as we mentioned earlier, Einstein’s model did not take into account the fact that light travels at a constant speed in all directions. This meant that his theory predicted that there should be no such thing as redshift the phenomenon where light from distant galaxies appears shifted towards longer wavelengths due to their motion away from us. But this was not observed in practice, and it became clear that Einstein’s theory needed some adjustments.

In order to account for redshift, Einstein added a new term to his equations called “cosmological constant”. This term represented the idea that space itself is expanding over time, which would cause light from distant galaxies to appear shifted towards longer wavelengths due to their motion away from us. However, this theory was not well-received at the time and Einstein eventually abandoned it in favor of a simpler model called “general relativity”.

In general relativity, space is no longer considered as an absolute entity but rather as a dynamic fabric that can be warped by massive objects like stars and galaxies. This means that light from distant galaxies will appear shifted towards longer wavelengths due to the curvature of space-time caused by their motion away from us.

So what does this mean for our understanding of the universe? Well, it suggests that the universe is not static but rather in a constant state of expansion and contraction over time. This idea has been confirmed by numerous observations, including the discovery of cosmic microwave background radiation which provides evidence for the “big bang” theory of the universe’s origin.