Our universe is getting bigger and bigger, we have known this for sure for exactly 90 years. It was the astronomer Edwin Hubble who discovered this in 1929 while observing other galaxies. If you take a look back at it today, you can only take your hat off with the greatest respect for this work!
Now more in detail.
Among other things, he found that the galaxies not only move further away, but the further away they are from us, the faster they move.
The fact that all galaxies are moving away from us must be interpreted simply as an expansion of the universe itself. There is a linear relationship between the so-called radial velocity and the distance of a galaxy…it is described by the very well known Hubble law.
And the constant that mediates between the two quantities, that determines how fast the speed of the galaxies increases with their distance, is the Hubble conatant.
Be careful, it should be called the variable constant!
Be honest! …. sounds strange or rather a bit confused! This name, given by science, is very misleading. According to research, this Hubble constant has constantly changed its value since the Big Bang….and by the way, its current value is described with the symbol H0.
If this value is not only vaguely determined, but specified down to the last detail, then a lot of interesting information about our universe is revealed. To be more precise, the word „specify“ can be formulated differently, or rather, „derive information“.
Let me list a few examples. The value of the Hubble constant contains the age of the universe: Look here, calculate how long it took for the known universe to develop since the Big Bang at a known rate of expansion to its current known size. The value to be obtained then, however, provides additional clues for the cosmological model, namely how our universe can be described. I would point to the nature of dark energy or the physics of neutrinos.
The question that arose very quickly was how precise the value of the Hubble constant was; it was disputed for a long time. The very great difficulty of the measurement results from the complicated determination of cosmic distances, because this is due to the fact that we can only see our visible universe as a projection on a two-dimensional celestial sphere. It is much easier to measure the radial velocities of cosmic objects using the Doppler effect, because this leads to a movement-dependent shift of spectral lines. Looking back, in addition to the method of determining the current value of the Hubble constant on the basis of precise distance and velocity measurements, an alternative method of measurement based on the cosmic background radiation was used.
Please, dear readers, take a look at the diagram now.
So in Hubble’s diagram there are just over thirty measurement points and they were very irregularly distributed.
Of course, there is a short description, so…the Hubble diagram as follows:
The distance of the objects is plotted horizontally and the so-called escape velocity is plotted vertically (of course, carefully corrected for the proper motion of our solar system, like all its legacies ….).
– Black dots represent objects that were measured individually.
-Crosses, are mean velocities of 22 nebulae whose distances could not be determined by him individually.
-Circles are to show nebulae whose objects he could not resolve individually.
………………..-…A dashed line then results considering the circles, but the solid line approximates the black points. It must be noted, the slopes of both straight lines are wrong from today’s point of view. But the basic idea of a straight line is very remarkable, because it is truly groundbreaking.
As we always say today when someone has had the courage to take a gap…e.g. …A strong piece…!!!
Hubble was the kind of scientist who had the courage to draw a line through a bunch of dots and say: „That’s it“ !
However, without such self-confidence he would not have been called Hubble, and that’s what you need when you portray such a scientist.
I can’t help but say that Edwin Hubble simply wrote „physics history“. His insane diagram – the Hubble diagram, which was also later named after him – clarified the connection between the distance and escape velocity of suns.
In even simpler terms, the data he cited clearly prove that objects viewed from Earth in any direction move away from us faster the further away they are !!!!
The static universe died, or more precisely, it was dead. This meant that the hope of many scientists that the previous theory would be preserved was no longer tenable. It was simply displaced by an expanding universe.
Now it did many scientists a world of good to say that the everlasting evolution had finally met and challenged several wrong thinkers in natural science as well.
What I have noticed more and more often in the course of my life, from one year to the next, is that in the biological „progression“ of all organisms, i.e. in their habitat, nothing has ever behaved statically. There has always been a diligent evolution there. The weak or late dynamic ones were always displaced and were then no longer there.
So it is quite simple to state : …… that scientific theories are also subject to an evolutionary principle. To put it even more clearly: „the natural enemy of the theory here, however, is not another theory again, but the experiment confirmed as correct“.
I like to come to another „insanely remarkable“ „scientist“, or better probably unique thinking human being of the early 1900s. ￼
It is Albert Einstein ( 1879-1955).
I have something specific to admire about this cosmo-physical genius….namely his work, which to this day cannot be refuted.
Looking at the chronological sequence, one can see that he had already developed the ………. general theory of relativity years before Hubble’s discovery. And it can be clearly stated that its equations necessarily involve an expanding universe !!!!!!!!!
I simply refer to him as one of the most important and world-renowned scientists in the history of science in the modern era, which I mentioned earlier.
In particular, his research results on the structure of matter, space and time, as well as on gravitation, which appears again and again, are worthy of mention. Concepts that, some people think, are easy to deal with. But be careful not to judge too quickly, in my opinion these terms must always be considered in the context of the Newtonian view of the world. Because it was precisely gravitation that brought it down.
A few words on the nature of gravitation
Gravity (from the Latin gravitation for „gravity“), also called gravitational force or mass attraction, is one of the four basic forces of physics.
It manifests itself in the mutual attraction of masses and it decreases with increasing distance of the masses, but has an unlimited range. What is also worth mentioning is that, in contrast to the -electrical or -magnetic- forces, it cannot be isolated, or even better, shielded.
Einstein’s main work is clearly the theory of relativity, which made him world famous. His first work, entitled „On the Electrodynamics of Moving Bodies“, appeared as early as 1905; the content of this work is today referred to as special relativity. In 1915, the general theory of relativity was published.
The topic of „quantum physics“ was not spared either, of course, if I consider that so lightly thrown around. Or rather, they were of course essential contributions to the „early“ period. ……..and, where is the Nobel Prize? ????
He received it, by the way, for his merits and outstanding work in theoretical physics.
I’m sure the term „photoelectric effect“ means a lot to some curious readers. He discovered its law. For this he was awarded the Nobel Prize in 1921, which was presented to him in 1922.
Albert Einstein is considered the epitome of a researcher and genius.
He also used his extraordinary fame outside the world of science in his work, for example, for international understanding and peace.
I say it again: Einstein was before Hubble and, by the way, he died two years after Hubble’s death. (1955) Let’s go back to the general theory of relativity, it was published in 1915. But it was only 14 years later that Hubble’s important observations came to light. This means nothing other than that Einstein’s theory was floating in a vacuum for a long time.
Not quite, because some of its predictions had already been confirmed by observations: They were the gravitational diffraction of light and the strength of Mercury’s perihelion rotation …more on that in a moment!
I suggest we now approach these previously mentioned topics a little more slowly. First, Albert Einstein’s General Theory of Relativity predicted that when light moves past heavy masses, there the path of the light will be bent. You just heard right…….then its paths will be bent, this in turn is called „Gravitational Diffraction“ …..and this remarkable effect has made General Relativity very famous unchallenged.
…and that’s not all as far as gravitational diffraction of light is concerned:
General relativity predicts something else, it is not only mass, but according to the well-known formula E = m c² …..auch energy that acts, namely gravitationally. Newton was not of this opinion ! …even light is thus – in contrast to Newton’s theory – deflected by massive objects.
The following picture is to illustrate the curvature of space by a massive object geometrically (two-dimensional). The photons choose the fastest path. In a curved space-time, this is no longer a straight line, but a curved line.
But now, as announced, to the perihelion rotation of Mercury. It is the interaction of the planet with the gravitational field of the sun. This „egg“ around the focal point, triggered by disturbances of the planets Venus and Earth, was already known before Einstein, but there was a deviation of 43 arc seconds per hundred years between the measured data and the theoretical calculation. General relativity was able to attribute this change in orbit to the curvature of space caused by the presence of the sun.
Years before Hubble’s discovery, Albert Einstein had already developed the general theory of relativity. Its equations necessarily involve an expanding universe. Only with great difficulty – with the help of a mathematical trick in the form of a cosmological constant – was the theory compatible with a static universe.
He had simply added a constant with the dimension inverse surface, and so cleverly that everything fitted again.
…..and so that it stays in the brain memory :again !
The gravitational diffraction of light: The general theory of relativity predicts that not only mass, but according to E = m c² also energy has a gravitational effect. Thus – in contrast to Newton’s theory – light is also deflected by massive objects. The previous picture is intended to illustrate the curvature of space by a massive object geometrically (two-dimensionally). The photons choose the fastest path. In a curved space-time, this is no longer a straight line, but a curved line.
….The perihelion rotation of Mercury is the interaction of the planet with the gravitational field of the Sun. This „egg“ around the focal point, triggered by disturbances of the planets Venus and Earth, was already known before Einstein, but there was a deviation of 43 arc seconds per hundred years between the measured data and the theoretical calculation. The general theory of relativity……… was able to attribute this change in orbit to the curvature of space caused by the presence of the sun.
….but now really to the perihelion rotation of Mercury.
On this subject, here is another anecdote that has come down to us. The scientist Arthur Eddington went on an expedition to Africa. What did he have in mind ?
He wanted to research special data of a „solar eclipse“ and present them at home in England to an illustrious circle, namely the Royal Society.
It must be added that with the result of this expedition, the survival of Einstein’s general theory of relativity was at stake.
For this had made a clear prediction that light is bent at heavy masses to such an extent that the apparent positions deviate from the actual positions of the light sources, i.e. the stars behind them. For an observation of this subtle effect, however, the all-dominant luminosity of the sun must be covered – hence the solar eclipse.
And the natural phenomenon fortunately cooperated. Sir Arthur Eddington had brought exactly the data that confirmed the theory.
Arthur Stanley Eddington (1882 – 1944)
If we take a look at the subject of the interaction of electromagnetic waves in gravitational fields nowadays, we can simply conclude that they can really be measured accurately. This is because we are not dependent on a corresponding overall situation, such as that resulting from the coincidence of special circumstances or conditions from a solar eclipse and background radiation. – We send suitable measuring instruments behind the Sun. For example, the Cassini probe. In this way, it was possible to prove that electromagnetic signals experience a delay when passing through gravitational fields according to the general theory of relativity. This effect, which we call Shapiro’s effect, was confirmed with an accuracy of 0.001 percent.
Clearly, it had to be stated again that the general theory of relativity had already explained many things a hundred years ago. The moment Edwin Hubble made his very valuable observation data public, one could speak of the definitive presence of general relativity in science.
Part 4 will follow shortly