The article, despite being controversial, was published in the latest issue of Astronomy magazine, published by the Israeli Astronomical Society
Yehuda Sabdarmish
Direct link to this page: https://www.hayadan.org.il/sverdermish010304.html
An expanding universe and the speed of light
By
Sabdarmish Yehuda
introduction
The speed of light, which is the basis of the theory of relativity, is seen as a constant and stable quantity, perhaps the only one in nature, by most scientists. In recent years, the author of the article, (and others), believe that the speed of light is not a constant size and is smaller as the universe expands.
With all the problematic that such a statement entails, it can solve a number of cosmological problems, such as:
The inflationary expansion of the universe in the first second of the Big Bang. A speed of light greater than 300,000 km per second would explain the contradiction.
About three years ago, the author of the article wrote an article called "Theory of the Simple Universe" ("Astronomy", Volume 26, Issue 3, December 2000). The article tried to show an alternative way of explaining the universe. The article provoked many reactions at the time, some sympathetic and some fatal. To remind you, the theory treated the universe as a great ideal gas and reached different conclusions, some acceptable and some not in the various fields of physics and astronomy.
One of the conclusions reached by the theory was that the speed of light is not constant, and is actually proportional to the root of the background temperature of the universe.
That is, for example, when the background temperature of the universe was one hundred times that of today, i.e. 273 degrees Kelvin, then the speed of light was ten times that of today, that is, three million kilometers per second, and when the background temperature of the universe will be 81 percent of what it is today, then the speed of light will be 90 percent From what it is today, i.e. about 270,000 km per second. (root of 0.81 is 0.9), etc.
Today, the background temperature of the universe - 2.73 degrees Kelvin, seems stable and almost unchanged over time.
The question arises: can the tiny changes over time in the magnitude of the background temperature of the universe cause a significant change in the speed of light as is supposed to result from the "simple universe theory", a change that we can measure? In this way, we can once and for all check the correctness of the aforementioned alternative theory.
The numerical calculations
The numerical calculations are not complicated. The way of proof will be in the following steps:
A. Testing the expansion rate of the universe
B. Checking the resulting background temperature drop.
third. Testing the expected change in the speed of light resulting from the "simple universe theory"
proof:
We are given Hubble's constant which says that the universe expands at a rate of 65 km per second per megafarsec, meaning that if we were in the center of a cosmic sphere with a radius of 1 megafarsec, then a second later the radius would increase by 65 km.
Let's check how much is one Mega Persec per km. From the knowledge that one persec is 3.2616 light years, and one light year has 63240 astronomical units, and each astronomical unit has 149.6 million km, we will accept that one mega persec has:
R=3.2616*10 /6*63240*149.6*10 /6=3.09*10 /19 km
That is, 3.09 times ten to the power of nineteen kilometers.
We will now check by how many km the aforementioned radius will "grow" as a result of the Hubble constant.
From the knowledge that Hubble's constant is 65 km per second per megafarsec and there are 31,557,600 seconds in a year, we will get that over the course of a year the same radius with a length of one megafarsec will increase by:
65*10 /6*31557600=2.05*10 /9 km /mpc
That is, the radius increases by 2.05 times ten to the power of nine kilometers per year per Mega Persec.
That is, the radius increased from 3.09 to 3.090205 (in both cases doubled by ten to the power of nineteen km per million years per megasec).
Hence, the same Mega Persec increases times: 3.090205/3.09=1.0000665
In a conversation with Eran Ofek, who has a master's degree in astrophysics, it was clarified to me that the wavelength of the background radiation undergoes the same expansion as the expanding universe, and hence, the background temperature of the universe is inversely proportional to the linear expansion of the universe.
That means after a million years the temperature will be 1/1.0000665=0.9999337
from the background temperature today.
And according to the theory of the simple universe, the speed of light will decrease proportionally to the root of this number, . That is, proportional to 0.9999668, that is, the speed of light will decrease in part:
1-0.9999668 0.0000332 =
And since the speed of light in cm is about 3*10/10, then the reduction of the speed of light in cm per second per million years will be:
3*10 /10*0.0000332= 996000 cm
Conclusion from the "simple universe theory": the speed of light will decrease by about XNUMX cm per second per year!
In addition, an accurate measurement of the change in the speed of light will allow the Hubble constant to be accurately determined. This is due to the fact that the magnitude of the change in speed is due to Hubble's constant.
Is the magnitude of such a change measurable? The author of the article thinks it is given. Already now it is possible to get the magnitude of the speed of light with an accuracy of one meter. In John Gribbin's book: "Guide to the Cosmos" the value for the speed of light appears: 299,792,458 meters per second.
In conclusion
In this article, the author of the article showed the possibility that the speed of light slows down by about 1 cm per second, per year, in the coming years (!).
Is it possible/should we organize an experiment over time to test this?
It is clear that if the expected change in the speed of light is not revealed, the smile will return to Einstein's face after three years the author of the article has doubted his words.
But of course the second option also exists and the change in the speed of light will be revealed. In this case, the theory of relativity will be dealt a severe blow, and the author of the article is the one who will smile!.
They knew astrophysics
The Israeli Astronomical Society
https://www.hayadan.org.il/BuildaGate4/general2/data_card.php?Cat=~~~784321061~~~129&SiteName=hayadan
