The source of the background radiation is the radiation from the recombination period of the Big Bang, when the universe was about 380,000 years old. The cooling is due to the adiabatic expansion of the universe. This means that the heat was not transferred to a mass but instead the expansion of space results in an increase in photons wavelength as it moving through the universe.
Except now you aren't answering the question that was asked... Origin said "yes", which is correct. You brought in the whole "complex vs simple" bit - ultimately, the answer is simple - yes, it is cooling as it expands. While explaining the in depth mechanics behind which how it is cooling may be complex, the simple answer of "Conservation of Energy" is accurate. Now, if you are claiming the universe is not adiabatic, that would undoubtedly change things - but then you would have a whole new claim to make.
You are telling me I have to accept when the universe was 380,000 the emission was XXX the at the present the emission is XXX - A ?
Rather I will take you to photon gas...https://en.m.wikipedia.org/wiki/Photon_gas See the table, there is a formula for entropy (S) which connects V and T, for the adiabatic expansion of the universe this entropy is constant, that will give the inverse relationship between V and T. Kittamaru : There is a very big problem in your argument, you took it very casually, on top of that you kept on harping about energy Conservation etc, in GR which is the theory of universe expansion, energy Conservation is an issue?
Pl see my first post as early as #5...I brought in the adiabatic expansion, so please do not misquote and create problems.
First line is irrelevant as there is no mass away from the universe, it's a closed system. Second line is true but not the correct explanation for reduction in temperature.
If I'm not mistaken, Conservation of Energy is a rather fundamental law of physics, is it not? Are you suggesting you have a situation where you just... discard it? Post number five was posted by MathMan - I presume you mean post number six: You also said: Which would seem to suggest a thought that the expansion is not adiabatic as either it is A) Adiabatic, and thus expansion will result in a decrease in temperature or B) It is not adiabatic and the temperature could change in a different fashion based on whatever additional energy input is observed. Which is it? The God, you are the one being vexatious in your posting; you do not get to try and pin blame for this on others. Also, I cannot "misquote and create problems" when I directly quoted you. Now, if you are arguing that it is in fact more complex than expansion of a closed space without any additional energy input results in a net decrease in energy and temperature, then you need to pony up and explain how you come to such a conclusion. Case in point: Origin didn't say there was any "mass away from the universe" - seems you are the one attempting to misquote... Secondly, if that is "not the correct explanation", then prove it.
Kittamaru, Good following. I am out of this thread as I have stated exactly as per prevalent physics. I will interject only if any poster writes inaccurately. I am in no mood to argue with you, Kittamaru, because I cannot win you, you will never acknowledge or concede. And yes, on energy conservation in GR, please start a new thread, we will discuss.
No. You are free to accept what ever you desire. What I am telling you is that the evidence indicates that the universe was about 4000K (as would be measured as blackbody radiation) when it was 380,000 years old and the expansion of the universe since then has resulted in that blackbody radiation now being about 2.7K. Are perfectly free to ignore this information and go on your merry way.
So, you only intend to tell people "no you are wrong" and then not substantiate it? Also - all you need to do to "win me" is to provide some sort of evidence to back your claims.
Why? What is wrong with my explanation? Why introduce unnecessary concepts such as photon gases, when there is no need for them? Especially since the article you refer to requires walls, i.e. a containment of the photon gas by matter. This obviously is not the situation we have with the expanding universe. (For what it is worth, by the way, the expansion is self-evidently adiabatic, since there is by definition no place outside the universe with which energy can be exchanged.) But now I see you are "out of this thread". Perhaps that is just as well.
Perhaps another consideration is that the universe is expanding into a permittive state of absolute zero temperature. Seems that at the very outer edges of the universe expanding space any existing energy is further cooled and may be slowing down but being pushed outward by our Dark energy. Which would suggest the creation of a wave function of expansion and contraction, but these frequencies are way below our ability to observe or experience them. We can measure but not physically experience such long wave lengths. We could be riding a frequency with a 2 billion year cycle. Can I draw a similarity of a tsunami wave function. Part of the ocean rises, but the wave frequency is so long that to any ship in mid ocean this would be unnoticeable, until the tsunami enters shallower water, and the wave function becomes devastatingly noticeable, until it has expended its energy and begins to draw back towards the ocean.
You might want to read up a little on the law of conservation of energy and the law of conservation of mass. They are fundamental concepts in physics.
There's still the idea of virtual particles forming matter; just sayin' cause this thread could be a lot cooler.
There is nothing wrong as such in your statements that on expansion wavelength increased etc. But how does it prove reduction in temperature? Can you give a formula wherein temperature is a function of wavelength or frequency or energy density of radiation? On the other hand adiabatic expansion and entropy treatment proves that VT^3 must be constant where V is volume, thus expansion that is increase in V will lead to decrease in temperature.
