How can we be sure of a singularity?

  • Thread starter neonpotato
  • Start date
  • Tags
    Singularity
In summary: Yes, I have read a bit about it. I think the most important paper I've read on the subject is "The Origin of the Universe: Why There Is a Bang and What Comes After" by Alan Guth. It's a great article and it provides a lot of good information.In summary, the evidence for an all-containing singularity being the initiation of the big bang is inconclusive.
  • #1
neonpotato
3
0
I have often been told that at the start of our "universe" (I prefer "self-contained energy system" - SCES, myself) all energy was contained in a singularity. What is the evidence for this all-containing singularity being the initiation of the big bang?

Is it not reasonable that the extremely dense core of a shrinking SCES (or universe) could have exploded with energy already in existence around it?

Any illumination would be appreciated.

Please be aware my understanding of physics is limited.
 
Space news on Phys.org
  • #2
What the state of the universe at t=0 or t<0 (big bang starts time) is an open question. There are many ideas floating around, but there is (at the moment) no way to test them.
 
  • #3
neonpotato said:
I have often been told that at the start of our "universe" (I prefer "self-contained energy system" - SCES, myself) all energy was contained in a singularity. What is the evidence for this all-containing singularity being the initiation of the big bang?

Is it not reasonable that the extremely dense core of a shrinking SCES (or universe) could have exploded with energy already in existence around it?

Any illumination would be appreciated.

Please be aware my understanding of physics is limited.

This has puzzled me as well. My take is this. When you split a rock, you might get a few sparks, perhaps a bit of radiation and some crumbs. When you split an atom you get quite a bit more energy released than from spliting a rock. By these two examples, in tandem, I would suggest that when a sub-atomic particle (wave) is either compressed by, or forced to dispense into a "void", a great deal more energy is released than what is released by splitting an atom... in fact probably 10 to the power of 9 more energy than is released than when an atom is split.

Then again, I've been wrong before.
 
  • #4
baywax said:
... My take is this. When you split a rock, you might get a few sparks, perhaps a bit of radiation and some crumbs. When you split an atom you get quite a bit more energy released than from spliting a rock. By these two examples, in tandem, I would suggest that when a sub-atomic particle (wave) is either compressed by, or forced to dispense into a "void", a great deal more energy is released than what is released by splitting an atom... in fact probably 10 to the power of 9 more energy than is released than when an atom is split.

Then again, I've been wrong before.

I don't follow. How is this related to my question?
 
  • #5
neonpotato said:
...
Is it not reasonable that the extremely dense core of a shrinking SCES (or universe) could have exploded with energy already in existence around it?
...

check out Einstein Online, an authoritative, mainstream, up-to-date website maintained as part of the Albert Einstein Institute's public outreach program.
http://www.einstein-online.info/en/spotlights/cosmology/index.html

it's great. Atyy (who posts here sometimes) told us about it.
It has a page that discusses what you are talking about
http://www.einstein-online.info/en/spotlights/avoiding_the_big_bang/index.html
and it also has useful page regarding singularitie and the different things people mean by "big bang" which can help us avoid confusion.
http://www.einstein-online.info/en/spotlights/big_bangs/index.html
 
Last edited by a moderator:
  • #6
Ashtekar + bojowald state

"The question of whether the universe had a beginning at a finite time in the past is now `transcended'. At first, the answer seems to be `no' in the sense that the quantum evolution does not stop at the big-bang. However, since space-time geometry `dissolves' near the big-bang, there is no longer a notion of time, or of `before' or `after' in the familiar sense. Therefore strictly, the question is no longer meaniful. The paradigm has changed and meaningful questions must noe be phrased differently, without using notions tied to classical space-times"
 
  • #7
GR is a relational theory in which you have to pick a dynamical observable to take on the role of a clock , but in the deep quantum mechaical region of the early universe there are no classical observables...
 
  • #8
The 'big bang' is the sound of one hand clapping [in zen speak]. Since no classical observables existed at t=0, as Julian noted, using yardsticks and clocks to describe this realm is like trying to announce a a hockey game by weight and color.
 
  • #9
julian said:
GR is a relational theory in which you have to pick a dynamical observable to take on the role of a clock...

that's right! Agrees with what I've read about the computer modeling of bounce at Penn State for instance. A dynamical observable, e.g. connected to a matter field, is included and serves as clock. The model is quantum rather than classical in this case. they don't have time as such, and choose one of the physical elements in the picture to use as a clock.

Have you read much about it? You sound as if you may have. Do you have any papers you want to give links to?
 
  • #10
neonpotato said:
I don't follow. How is this related to my question?

I'm trying to explain my thoughts concerning what caused the big bang. So, the wave or particle I mentioned that is compressed or dispersed and out of balance with the "void" (lack of time, space) is all of what's left of the old universe or "p-brane".

Today is is evident that the universe is expanding and that objects are getting further apart. I have extrapolated this motion to a point where even sub-atomic particles have separated by great distance until space and time collapse, leaving only isolated sub-atomic particles surrounded by a void. At this point I am proposing that some sort of interaction between the sub-atomic particle and the void causes a rather large explosion and expansion. Then there is another universe developing.

Make me wrong!
 
  • #11
The note I made was cautionary - my understanding isn't detailed. Tied with the notion of time is energy - so I was unsure of the relavence of SC(Energy)S. I wish to understand these things better myself.

Something that confuses me: The results about singularity avoidance so far pertain to the kinematic level (I think) - but things can change dramatically at the physical (dynamical level). Thiemann has written a paper in which he describes the reduced pahse space quantization of GR (which explicitly operates at the physical level) and proclaims it may resolve the singularity problem dynamically. The thing is, it is an essential feature of the RPSQ that the dynamical time variable is described classically, which is at odds with what I said before!

ian
 
  • #12
I will try to bring together the list of references that contribute to my "understanding" of the issue
ian
 

Related to How can we be sure of a singularity?

1. What is a singularity?

A singularity refers to a point in space and time where the laws of physics break down and traditional theories cannot explain what is happening. In the context of cosmology, a singularity is often associated with the Big Bang theory, where the entire universe was condensed into an infinitely small and dense state before expanding.

2. How can we prove the existence of a singularity?

Currently, there is no direct way to prove the existence of a singularity. We can infer its existence through mathematical models and observations of the universe, such as the expansion of the universe and the cosmic microwave background radiation.

3. What evidence supports the idea of a singularity?

Aside from mathematical models and observations, scientists have also found evidence of a singularity in the behavior of black holes. Black holes are believed to have a singularity at their center, where the gravitational pull is so strong that even light cannot escape.

4. Can we ever be certain of a singularity?

Due to the limitations of our current understanding and technology, it is unlikely that we will ever be 100% certain of a singularity. However, as our knowledge and technology continue to advance, we may be able to gather more evidence and gain a better understanding of these phenomena.

5. What implications does the existence of a singularity have on our understanding of the universe?

The existence of a singularity challenges our current understanding of space and time and raises questions about the origins and fate of the universe. It also highlights the limitations of our current scientific theories and the need for further research and exploration to fully grasp the complexities of the universe.

Similar threads

I Question about the big bang singularity
    • Cosmology
Replies
13
Views
2K
B Big Bang Question -- How was the first matter formed?
    • Cosmology
2
Replies
69
Views
4K
I Big Bang Singularity: Was It As "Infinitely Dense" As We Think?
    • Cosmology
2
Replies
35
Views
4K
I How does the Singularity produce all the diverse matter in the universe?
    • Cosmology
Replies
9
Views
1K
B Which Hawking paper? (no singularity at the beginning of the universe)
    • Cosmology
Replies
2
Views
2K
I Shouldn't the Big bang be physically impossible?
    • Cosmology
Replies
25
Views
2K
B Do we still live in a Big Bang Singularity?
    • Cosmology
Replies
14
Views
3K
B The big bang singularity and black hole singularity
    • Cosmology
Replies
5
Views
2K
I Kerr disputes singularities in Kerr Black Holes
    • Special and General Relativity
Replies
7
Views
1K
I Some questions about Cosmic Inflation
    • Cosmology
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top