Universe from nothing, again....

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In summary: Mars?Intergalactic space is much colder than the interstellar medium or the Sun's atmosphere.The temperature of the interstellar medium varies depending on location, but it is generally colder than the Sun's atmosphere.It seems like we're going to need more information to answer this question.In summary, the universe seems to come from nothing, but there is still a lot that we don't know about it.
  • #1
Stephanus
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Dear PF Forum,
Sorry to ask this question again after so many threads here and in google that explain nothing!
And many controversies, too.

1. Does the universe really comes from nothing? Yes or No?

-------------------------------------------------------------------

2. if "YES" then...
What is this? This is 100% not 0%. Is this free lunch?
http://en.wikipedia.org/wiki/Universe
Ingredients:
Ordinary matter (4.9%),
dark matter (26.8%),
dark energy (68.3%)
Other question, while I was still reading.
http://press.web.cern.ch/backgrounders/matterantimatter-asymmetry

... – about one particle per billion – managed to survive...

http://en.wikipedia.org/wiki/Universe
Average temperature 2.72548 K
That CERN article, as many you already know, is about 1 second (more likely less) after big bang.
1 in a billion!. So..., 999,999,999 other particles * 2 for anti matter * c2 are roaming around the universe as energy, is that right?
3. Where are the energy?
Does it present as 2.7K warming the universe?
Or 2.7K comes ONLY from sum(volume of each star * each temperature)/volume of the universe?
Or 2.7K come from the energy from 999,999,999 particles and stars?
But intergalactic space has 1 million K temperature??
http://physics.stackexchange.com/questions/25378/how-vacuous-is-intergalactic-space
Hardly 2.7K?

Thanks for any answer.
 
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  • #2
Stephanus said:
1. Does the universe really comes from nothing? Yes or No?
Philosophy, or at least not decidable with current observations and theories.

Stephanus said:
1 in a billion!. So..., 999,999,999 other particles * 2 for anti matter * c2 are roaming around the universe as energy, is that right?
The universe evolved significantly since that time, but if you count the number of photons in the cosmic microwave background (which was emitted much later), you will still get a number larger than the number of other particles in the universe.
The amount of light from stars is very small compared to that, unless you happen to live very close to one (as we do).
 
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  • #3
mfb said:
The amount of light from stars is very small compared to that, unless you happen to live very close to one (as we do).

Thanks mfb for your answer, again. I remember you replied to my question, "Universe Frame of reference" such a good explanation.
Perhaps I should calculate 700 000 km3 (sun radius) * 4/3 * π * 6000K * number of stars / universe volume before I ask.
Those number,
Sun radius: perhaps not the medium radius of all stars in the universe
6000K: perhaps offs by some considerable degree, as I only take sun temperature as an example.Thanks

Steven.
 
  • #4
Just one comment regarding your point 3 : 2.7K is the temperarure of the CMB, which is completely distinct from the radiation emitted by stars (much hotter and very far from equilibrium with the CMB yet, thankfully for us). Also I am not sure about the "warming" part since that CMB radiation is cooling down gradually since its emission.
The high temperarure in outer space is also (obviously ! )not in equilibrium with the CMB, but as I understand it, it represents the temperature of a very dilute gas and doesn't contribute much to the total energy density.
 
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  • #5
Stephanus said:
1 in a billion!. So..., 999,999,999 other particles * 2 for anti matter * c2 are roaming around the universe as energy, is that right?
Yes and no. The other particles annihilated with one another, mostly becoming electromagnetic radiation. Essentially, when the temperature got low enough, the particles would annihilate faster than they were produced. This caused the energy of the annihilating particles to be dumped into other relativistic fields, which in turn caused the temperature to stabilize for a time before it started dropping again once all of the matter/anti-matter pairs had annihilated.

Stephanus said:
3. Where are the energy?
Redshifted away, mostly. The expansion of the universe causes radiation to lose energy over time.

If you have a box that is expanding with the universe, and that box is filled with radiation of a certain temperature, and that box expands by a factor of two, then each photon in the box has its wavelength doubled, which cuts the energy in the box in half and the temperature to also drop in half.

But if you have the same box with normal matter in it, the energy of the normal matter stays constant over time.

So while we started with normal matter only being that one part in a billion of leftover imbalance, the matter has stuck around while the radiation has lost its energy with the expansion.

Stephanus said:
Does it present as 2.7K warming the universe?
Yes. That is the remainder of the redshifted radiation energy.
 
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  • #6
Dear PF Forum,

Reading further, I find this.
http://physics.stackexchange.com/questions/25378/how-vacuous-is-intergalactic-space
...this intergalactic medium is millions of degrees!...

1. Is that true? Or it is limited to some region?
2. Isn't it 2.7K?

And some links suggest million of Kelvin tempererature. It's a rather overwhelming for me.
Are they trying to say, that between, let's say, the outer star of Wilky Way to Andromeda (and other intergalactic space), for 2 million ly, in that vastness of space, the temperature is million of Kelvin?

3. If that's true. Is that condition only applied to intergalactic space? What about interstellar medium, is it that hot? Or interplanetary, say within our solar system. But I 'know' that inside solar system, it can't get that hot, or we wouldn't have comets, or ISS for that matter.
So, if it's true. What's the difference between intergalactic and interstellar medium?

Thanks for anyone reading this.

Steven
 
  • #7
Stephanus said:
1. Is that true? Or it is limited to some region?
It is true for many regions.
Stephanus said:
2. Isn't it 2.7K?
Some gas is that cold, dust is at this temperature, but gas can be much hotter.

Stephanus said:
Are they trying to say, that between, let's say, the outer star of Wilky Way to Andromeda (and other intergalactic space), for 2 million ly, in that vastness of space, the temperature is million of Kelvin?
Which just means there are few isolated particles flying around at high speed. It's not like you would burn there - the gas is way too thin to have a notable effect on larger objects. Same for the interstellar and interplanetary medium.
 
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  • #8
Stephanus said:
Dear PF Forum,

Reading further, I find this.1. Is that true? Or it is limited to some region?
2. Isn't it 2.7K?

And some links suggest million of Kelvin tempererature. It's a rather overwhelming for me.
Are they trying to say, that between, let's say, the outer star of Wilky Way to Andromeda (and other intergalactic space), for 2 million ly, in that vastness of space, the temperature is million of Kelvin?

3. If that's true. Is that condition only applied to intergalactic space? What about interstellar medium, is it that hot? Or interplanetary, say within our solar system. But I 'know' that inside solar system, it can't get that hot, or we wouldn't have comets, or ISS for that matter.
So, if it's true. What's the difference between intergalactic and interstellar medium?

Thanks for anyone reading this.

Steven
It might help to read up on Reionization, which is the time when the intergalactic medium became hot:
http://en.wikipedia.org/wiki/Reionization
 
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1. What is the theory of "Universe from nothing"?

The theory of "Universe from nothing" proposes that the universe, including all matter and energy, originated from a state of nothingness. This concept is based on the idea that the laws of quantum mechanics and relativity allow for the spontaneous creation of matter and energy from empty space.

2. How does the theory of "Universe from nothing" explain the origin of the universe?

The theory suggests that the universe came into existence through a process called quantum fluctuations, where particles and antiparticles spontaneously appear and annihilate each other, leaving behind a small amount of matter. As the universe expanded, this matter eventually became the galaxies, stars, and planets that we see today.

3. What evidence supports the theory of "Universe from nothing"?

One of the key pieces of evidence for this theory is the observed expansion of the universe. This expansion indicates that the universe was once much smaller and denser, supporting the idea that it originated from a single point. Additionally, experiments in particle accelerators have shown that particles can indeed spontaneously arise from empty space.

4. How does the theory of "Universe from nothing" relate to the Big Bang theory?

The Big Bang theory and the theory of "Universe from nothing" are closely related, with the latter providing a potential explanation for the initial singularity that caused the Big Bang. The Big Bang theory describes the expansion of the universe from a hot, dense state, while the "Universe from nothing" theory offers a possible explanation for the source of this initial state.

5. What are some criticisms of the theory of "Universe from nothing"?

Some criticisms of this theory include the lack of a complete and testable mathematical framework to support the idea of particles spontaneously appearing from nothing. Additionally, the concept of "nothingness" itself is difficult to define and understand in the context of the universe. Some also argue that the existence of laws and constants in the universe suggests a more complex origin than simply arising from nothing.

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