Science terms and science questions

[Wolte]

I'm actually trying to find reasons why I was kicked out in an other forum a few years ago for asking a question. (the actual questions are numbered below)

Heres what I was trying to ask in short: "the universe is expanding accelerating (galaxies are travelling away from each other at an accelerating speed). It has been suggested (or proven?) that this is caused by dark energy in the/our universe. In pop science, I've heard many times that: 'there must be something pushing this accelerating expansion and that something is dark energy' ". Ok, I have nothing against this idea, but what bothers me the most, is that I see there are two possibilities for the accelerating expansion; either push or pull. So could there be something pulling the expansion (outside) our universe rather than pushing (from inside the universe, like dark energy)?

 

1. If there had already been something else before the big bang, with what word, would you describe everything (the known universe+something else)? I believe the universe is a bad word for "everything" , since it has "boundaries" and seems to be bound to just what we can observe.

2. Is it because we have no possibility to prove (or even observe) the asked question, that makes this unsuitable as a question for science? Follow-up: if we can't observe/prove something-> it doesn't exist?

3. If you were to ask this question, how should this be properly be asked in science?

[StringJunky]

27 minutes ago, Wolte said:

I'm actually trying to find reasons why I was kicked out in an other forum a few years ago for asking a question. (the actual questions are numbered below)

Heres what I was trying to ask in short: "the universe is expanding accelerating (galaxies are travelling away from each other at an accelerating speed). It has been suggested (or proven?) that this is caused by dark energy in the/our universe. In pop science, I've heard many times that: 'there must be something pushing this accelerating expansion and that something is dark energy' ". Ok, I have nothing against this idea, but what bothers me the most, is that I see there are two possibilities for the accelerating expansion; either push or pull. So could there be something pulling the expansion (outside) our universe rather than pushing (from inside the universe, like dark energy)?

 

1. If there had already been something else before the big bang, with what word, would you describe everything (the known universe+something else)? I believe the universe is a bad word for "everything" , since it has "boundaries" and seems to be bound to just what we can observe.

2. Is it because we have no possibility to prove (or even observe) the asked question, that makes this unsuitable as a question for science? Follow-up: if we can't observe/prove something-> it doesn't exist?

3. If you were to ask this question, how should this be properly be asked in science?

The universe is everything that exists. There are no boundaries unless you are talking about the observable vs the entire universe. The big bang is the beginning of a new epoch in the evolution of the universe and not the beginning of the universe itself; if it ever had one.

Edited May 1, 2019 by StringJunky

[Bufofrog]

17 minutes ago, Wolte said:

I'm actually trying to find reasons why I was kicked out in an other forum a few years ago for asking a question. (the actual questions are numbered below)

Kicked out of a forum for asking a question?  Are you sure there was not a bit more that resulted in you getting banned?

18 minutes ago, Wolte said:

Heres what I was trying to ask in short: "the universe is expanding accelerating (galaxies are travelling away from each other at an accelerating speed). It has been suggested (or proven?) that this is caused by dark energy in the/our universe. In pop science, I've heard many times that: 'there must be something pushing this accelerating expansion and that something is dark energy' ". Ok, I have nothing against this idea, but what bothers me the most, is that I see there are two possibilities for the accelerating expansion; either push or pull. So could there be something pulling the expansion (outside) our universe rather than pushing (from inside the universe, like dark energy)?

Since mainstream science is in agreement that there is no such thing as "outside the universe", I would have to go with the pushing possibility.  You would need some evidence to support your pulling idea.  The 'pushing' is not from the 'inside out', by the way, it is a 'pushing' in ALL directions.

22 minutes ago, Wolte said:

1. If there had already been something else before the big bang, with what word, would you describe everything (the known universe+something else)? I believe the universe is a bad word for "everything" , since it has "boundaries" and seems to be bound to just what we can observe.

2. Is it because we have no possibility to prove (or even observe) the asked question, that makes this unsuitable as a question for science? Follow-up: if we can't observe/prove something-> it doesn't exist?

3. If you were to ask this question, how should this be properly be asked in science?

1.  That is not a question, it is a belief.  That is fine, you can believe what you want, just don't expect people to agree with you.

2.  Science doesn't prove things.  If you cannot observe something that does not mean it does not exist - it just means there is no evidence for the 'thing'.

3.  I do not believe there is anyone here that is going to jump on you for asking a question, no matter how awkwardly, they will just ask for clarification.

 

 

[swansont]

40 minutes ago, Wolte said:

 1. If there had already been something else before the big bang, with what word, would you describe everything (the known universe+something else)? I believe the universe is a bad word for "everything" , since it has "boundaries" and seems to be bound to just what we can observe.

There is a distinction, as StringJunky has mentioned, between the observable universe and the universe. But there is no outside, so there can be no pull from the outside.

 

[Wolte]

16 minutes ago, StringJunky said:

The universe is everything that exists. There are no boundaries unless you are talking about the observable vs the entire universe. The big bang is the beginning of a new epoch in the evolution of the universe and not the beginning of the universe itself; if it ever had one.

Thanks. I think these observable vs entire universe, were the words I was looking for. I shall use them in the future for clarification.

[StringJunky]

9 minutes ago, Wolte said:

Thanks. I think these observable vs entire universe, were the words I was looking for. I shall use them in the future for clarification.

This is related to the rate of expansion beyond a certain distance out-stripping the speed of photons, which means information outside our observable sphere becomes increasingly faint with increasing distance. It's not a hard line.

[Wolte]

18 minutes ago, Bufofrog said:

Kicked out of a forum for asking a question?  Are you sure there was not a bit more that resulted in you getting banned?

Since mainstream science is in agreement that there is no such thing as "outside the universe", I would have to go with the pushing possibility.  You would need some evidence to support your pulling idea.  The 'pushing' is not from the 'inside out', by the way, it is a 'pushing' in ALL directions.

1.  That is not a question, it is a belief.  That is fine, you can believe what you want, just don't expect people to agree with you.

2.  Science doesn't prove things.  If you cannot observe something that does not mean it does not exist - it just means there is no evidence for the 'thing'.

3.  I do not believe there is anyone here that is going to jump on you for asking a question, no matter how awkwardly, they will just ask for clarification.

 

 

Thanks for your reply.

-Well not totally kicked out, but a quick shutdown of the thread, before any good-enough answers. I just figured, I wasn't wanted there anymore. ref: https://www.physicsforums.com/threads/is-something-pulling-our-universe.887846/

-ok, so the "push" word that I've heard is like more like "driving" (force) that covers either possibility.

-1. Ok, (though I need to think more closely this question/belief). Anyway, I don't "believe" my suggested idea or other theories without evidence, I just like to keep options open.

-2. ok.

-3. So far going good! :)

[Strange]

20 minutes ago, Wolte said:

Heres what I was trying to ask in short: "the universe is expanding accelerating (galaxies are travelling away from each other at an accelerating speed).

Before going into any more detail, I just want to make sure you are clear about the difference between expansion and accelerating expansion.  (Just because I have seen others confused by this.)

If the universe were expanding uniformly (as we thought before 1998) then we would see more distant galaxies moving faster than closer ones, in direct proportion to their distance. This is known as Hubble's law and has been known about since a few years before Hubble published the paper that gave it his name.

Some people confuse this increasing recessional speed with distance with "acceleration".

What was actually found is that the rate at which the universe is expanding has increased in the last few billion years. There are many possible explanations for this. The simplest one is to give a positive value to the "cosmological constant" term in the equations of GR. This term represents a constant "background" energy throughout the universe, which provides a positive pressure and accelerates expansion. Because we don't know what this energy is (or even if it really is the reason for the observed acceleration) it was given the name "dark energy".

Quote

Ok, I have nothing against this idea, but what bothers me the most, is that I see there are two possibilities for the accelerating expansion; either push or pull. So could there be something pulling the expansion (outside) our universe rather than pushing (from inside the universe, like dark energy)?

The trouble with this is that, without much knowledge of physics, it sounds plausible. There are several problems with it.

Firstly, a uniform mass around the outside the universe would not have any net pull effect on the universe. This is because the pull of the mass on one side would be balanced by the pull from the other side. This was proved by Isaac Newton (it is known as the Shell Theorem).

Secondly, even if an external pull like that were possible, it is difficult to see how it would cause the uniform increase in expansion that we see.

Finally, our current cosmological models do not have an "outside" of the universe.

58 minutes ago, Wolte said:

1. If there had already been something else before the big bang, with what word, would you describe everything (the known universe+something else)? I believe the universe is a bad word for "everything" , since it has "boundaries" and seems to be bound to just what we can observe.

There are several variants of the Big Bang model where there was "something" before the current phase of expansion. The most well known is, perhaps, the "big bounce" where an earlier version of the universe collapsed to a very high density before bouncing back to create the universe we see.

The universe we can see (which is a sphere with a diameter of something like 95 billion light years) is called the "observable universe" to distinguish it from the "whole" universe beyond that.

1 hour ago, Wolte said:

2. Is it because we have no possibility to prove (or even observe) the asked question, that makes this unsuitable as a question for science? Follow-up: if we can't observe/prove something-> it doesn't exist?

If someone can produce a mathematical model based on the question, and then predict what we should observe based on that model, then t can be scientifically tested.

1 hour ago, Wolte said:

3. If you were to ask this question, how should this be properly be asked in science?

1. Mathematical model.
2. Testable predictions.
3. Experiments/observations to test those predictions.

3 minutes ago, Wolte said:

Well not totally kicked out, but a quick shutdown of the thread, before any good-enough answers.

Some forums are very, very strict about only discussion established science. Others are a complete free-for-all. I think this one gets the balance about right (on average).

[Wolte]

5 minutes ago, Strange said:

If someone can produce a mathematical model based on the question, and then predict what we should observe based on that model, then t can be scientifically tested.

1. Mathematical model.
2. Testable predictions.
3. Experiments/observations to test those predictions.

 

40 minutes ago, Bufofrog said:

1.  That is not a question, it is a belief.  That is fine, you can believe what you want, just don't expect people to agree with you.

 

Ok. I think these two combined, explains the reason I was a bit refused at the other forum a few years ago. And I see, I was kind of "inventing a god", by skipping steps to beliefs.

But for the original question that is based on this discussion, would you state that: "It's possible, but there is no way of proving it. It's just a belief and not in anyway useful at the moment."

[John Cuthber]

1 hour ago, Wolte said:

I was kicked out in an other forum a few years ago for asking a question. (the actual questions are numbered below)

Interestingly, Google can't find where you asked them.

[Strange]

7 minutes ago, Wolte said:

But for the original question that is based on this discussion, would you state that: "It's possible, but there is no way of proving it. It's just a belief and not in anyway useful at the moment."

Given what we currently know it would not be possible (for the reasons given above).

[Wolte]

2 minutes ago, John Cuthber said:

Interestingly, Google can't find where you asked them.

Hi. Heres the link ones more: https://www.physicsforums.com/threads/is-something-pulling-our-universe.887846/

It wasn't a direct quote, rather a combination what I was trying to ask back then.

But I think I already got a good answer for all my questions (which on the same time answered the original question!) 

[StringJunky]

3 hours ago, Wolte said:

Hi. Heres the link ones more: https://www.physicsforums.com/threads/is-something-pulling-our-universe.887846/

It wasn't a direct quote, rather a combination what I was trying to ask back then.

But I think I already got a good answer for all my questions (which on the same time answered the original question!) 

Physics Forums is quite strict and has relatively little patience for dissenters but, having said that, you weren't treated unkindly and he did close it until you'd learnt more on the subject, not necessarily permanently

Edited May 1, 2019 by StringJunky

[Wolte]

Thank you again for all the answers. And especially Strange, for trying to answer the original question. I would have counter statements, but shall think it through later ones more.

 

To get back to the topic and the question on how to scientifically ask the original question.

With the given information on this thread, let me try to take a shot at it… Would the following way be a more scientific way of asking the same thing (by giving an example)?:

 

“(If it turns out there is an increasing amount of dark stuff in the observable universe)

Let us consider the observable universe as a filled water balloon and dark stuff (-matter, -energy or something) as air. And also, that someone has sticked a straw in the balloon, with the other end of the straw in the middle of the balloon and the other end outside the balloon.

Now, if there is an increasing air bubble inside the water balloon. Couldn't we, by studying the border of the air bubble and the water, determine if someone is blowing in to the straw to make the increasing air bubble or if someone is stretching the water balloon to get the air sucked in? Maybe by, for example, if there was a bigger or a smaller vacuum cap at the border than in elsewhere in the bubble/balloon”

This question/hypothesis might still be bad (and as untrue as the original), but was this any better for a question/hyphothesis for discussion? This should, at least in my theory, have a little bit better base for the mentioned requirements; 1. mathematical model 2. testable predictions 3. experiments/observations to the those predictions.

[Strange]

45 minutes ago, Wolte said:

Now, if there is an increasing air bubble inside the water balloon. Couldn't we, by studying the border of the air bubble and the water, determine if someone is blowing in to the straw to make the increasing air bubble or if someone is stretching the water balloon to get the air sucked in? Maybe by, for example, if there was a bigger or a smaller vacuum cap at the border than in elsewhere in the bubble/balloon”

One important characteristic of cosmological models is that the universe is homogeneous and isotropic. (In other words it is, on large enough scales, uniformly full of matter.) 

This is confirmed by observation. If there were some sort of bubble, we would see signs of it. We do, after all, see a number of voids of relatively low density of matter. But these are fairly evenly distributed and don't contradict the homogeneous nature of the universe. There is no sign of any bubble and border, such as you describe.

(And no, an analogy involving a straw blowing bubbles is not "more scientific". An analogy like this could be used to describe a model, but it is not a substitute for, or a starting point for, a model.)

51 minutes ago, Wolte said:

This should, at least in my theory, have a little bit better base for the mentioned requirements; 1. mathematical model

You don't have a mathematical model.