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Posted
4 minutes ago, swansont said:

No, actually, you don’t have to. It’s an analogy, and if you change it, it’s not correct anymore.

Nature is under no obligation to behave the way that you want it to.

There is no proof of this concept of expansion and if it is true then the universe is wider than it is deep and we don't even know the size in any direction.

Posted
1 minute ago, John John said:

There is no proof of this concept of expansion

Ignorance of the evidence is mot the same as nonexistence

1 minute ago, John John said:

and if it is true then the universe is wider than it is deep and we don't even know the size in any direction.

Not sure how you arrive at this conclusion, but since it’s based on not understanding the model, I think that’s moot 

Posted
3 minutes ago, swansont said:

If that’s your takeaway, you have some reading comprehension issues to address 

That is correct, I can't comprehend this at all. That is why I made an effort to explain my confusion regarding the rocket.

I wish you could explain what it is that I need to explain to you.

3 minutes ago, swansont said:

Ignorance of the evidence is mot the same as nonexistence

Not sure how you arrive at this conclusion, but since it’s based on not understanding the model, I think that’s moot 

Very well. If it is moot then I have nothing to explain.

Posted (edited)
27 minutes ago, John John said:

There is no proof of this concept of expansion and if it is true then the universe is wider than it is deep and we don't even know the size in any direction.

There's plenty of proof of expansion that proof doesn't necessarily involve redshift either. Though that's the more commonly known.

Another proof is the universe itself cooling down over time due to expansion and the thermodynamic laws in regards to an adiabatic and isentropic expansion.

The calculator in my signature can perform all the major FLRW metric calculations in proper distance.

It will even show that the Hubble constant is decreasing even though expansion is accelerating.

After work I cam readily detail the mathematics but I have a couple of articles for you to read.

 

://www.phinds.com/balloonanalogy/ : A thorough write up on the balloon analogy used to describe expansion
https://www.physicsforums.com/insights/inflationary-misconceptions-basics-cosmological-horizons/:Inflation and the Cosmological Horizon by Brian Powell
http://arxiv.org/abs/1304.4446 :"What we have leaned from Observational Cosmology." -A handy write up on observational cosmology in accordance with the LambdaCDM model.
http://arxiv.org/abs/astro-ph/0310808 :"Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe" Lineweaver and Davies

The balloon analogy by Phinds is one of the better ones done in addressing common misconceptions with regards to balloon analogy.

The Brian Powell article is from a Cosmologist (I personally know online when he used to visit another forum).

The lineweaver and Davies paper is highly cited and part of their dissertation paper.

Edited by Mordred
Posted
2 minutes ago, Mordred said:

There's plenty of proof of expansion that proof doesn't necessarily involve redshift either. Though that's the more commonly known.

Another proof is the universe itself cooling down over time due to expansion and the thermodynamic laws in regards to an adiabatic and isentropic expansion.

I don't deny the expansion I know it is real and things are progressively moving away from each other, but it is the way it is happening as a system.

Most of the objects are moving away but some are getting closer in our general fascinate and it is this among many other things that makes the overall structure of the universe very difficult to predict.

We don't know the size of the universe, and we don't know the shape.

There is no big picture, not yet anyway, so it is open to interpretation as to the fundamental structure and dynamics of all things relating to the overall system we can see.

Posted

Were not talking random velocities of galaxies in terms of expansion. Every object has its own inertia. When dealing with expansion your looking at the mean average separation distance.

Any object gravitationally bound is not expanding for example you and I are not expanding nor is a local large scale structure such as our local group, galaxies themselves etc.

Expansion arises from the voids between gravitationally bound objects and due to the effective energy densities.

Posted
9 minutes ago, Mordred said:

Were not talking random velocities of galaxies in terms of expansion. Every object has its own inertia. When dealing with expansion your looking at the mean average separation distance.

Any object gravitationally bound is not expanding for example you and I are not expanding nor is a local large scale structure such as our local group, galaxies themselves etc.

Expansion arises from the voids between gravitationally bound objects and due to the effective energy densities.

I understand expation, each galaxy is moving away from each other not traveling together. The further out galaxies are expanding faster than the closer galaxies. but still only moving at the same speed relative to each other.

Let's say it is cars on the road the car in front of you is going 10 km/h faster than you and the second car in front of you is going 20 km/h faster than you the speed of separation is only 10 km/h difference between each car. This is like the road is stretching not the cars moving by themselves.

Posted

The word universe means 'all that there is'.
Talking about the 'outside' and 'shape' of the universe ( or depth, width and center ) means that there is something outside of 'all that there is'. Nonsense by definition.

I had hopes for this thread when you first started it, but then you started posting nonsense like the above.
You're quickly running out of chances.

Posted
3 hours ago, John John said:

to imply I am incredulous is to say I have no right to have my opinion or belief but you do.

Wrong again. At least you’re consistent in your trollish nonsense. 

Posted
31 minutes ago, MigL said:

The word universe means 'all that there is'.
Talking about the 'outside' and 'shape' of the universe ( or depth, width and center ) means that there is something outside of 'all that there is'. Nonsense by definition.

I had hopes for this thread when you first started it, but then you started posting nonsense like the above.
You're quickly running out of chances.

You don't ask questions you just look for a fight, It is not my problem the James Web telescope has failed to fill your hopes.

26 minutes ago, iNow said:

Wrong again. At least you’re consistent in your trollish nonsense. 

You really do love the word troll.

Posted
3 hours ago, John John said:

don't see why you would say that, to imply I am incredulous is to say I have no right to have my opinion or belief but you do.

Stating what the science is, is not opinion or belief. This isn’t bullshitting while your English prof gets you stoned 

 

Posted (edited)
1 hour ago, John John said:

I understand expation, each galaxy is moving away from each other not traveling together. The further out galaxies are expanding faster than the closer galaxies. but still only moving at the same speed relative to each other.

Let's say it is cars on the road the car in front of you is going 10 km/h faster than you and the second car in front of you is going 20 km/h faster than you the speed of separation is only 10 km/h difference between each car. This is like the road is stretching not the cars moving by themselves.

That's a consequence of separation distance and Hubble law "the greater the distance the greater the recessive velocity" However that isn't a kinetic based velocity hence doesn't violate GR with greater than c recessive velocity.

The rate of expansion per Mpc is roughly 70 km/sec/Mpc 

PS this is described in the Brian Powell article I posted earlier.

 

Edited by Mordred
Posted
10 minutes ago, Mordred said:

That's a consequence of separation distance and Hubble law "the greater the distance the greater the recessive velocity" However that isn't a kinetic based velocity hence doesn't violate GR with greater than c recessive velocity.

The rate of expansion per Mpc is roughly 70 km/sec/Mpc 

PS this is described in the Brian Powell article I posted earlier.

 

Thats all good but it doesn't get us to the edge of the fiscal universe.

Posted
40 minutes ago, John John said:

Thats all good but it doesn't get us to the edge of the fiscal universe.

There is no edge. Picture yourself as a 2D dot on the 2D surface (no up or down) of a sphere, there is no edge.

Posted
1 minute ago, StringJunky said:

There is no edge. Picture yourself as a 2D dot on the 2D surface (no up or down) of a sphere, there is no edge.

I guess that is true if we live on or in a 2D balloon.

Posted (edited)
5 minutes ago, John John said:

I guess that is true if we live on or in a 2D balloon.

It's a way of describing how you can travel continually without ever reaching an edge. Everything that is in freefall moves in geodesics, so any path an object takes will always be curvilinear in the big picture. It will only appear flat at local distances.

Edited by StringJunky
Posted
3 minutes ago, StringJunky said:

It's a way of describing how you can travel continually without ever reaching an edge. Everything that is in freefall moves in geodesics, so any path an object takes will always be curvilinear in the big picture.

I see, thank you for taking the time to explain this to me.

Posted (edited)
5 minutes ago, John John said:

I see, thank you for taking the time to explain this to me.

Every discrete object in space is in freefall into some object, or gravitationally bound collection of objects, of higher mass/energy.

Edited by StringJunky
Posted
1 minute ago, StringJunky said:

Every discrete object in space is in freefall into some object or objects of larger mass/energy.

That is what Newton said about the apple but it pulls the Earth up just a little bit.

Posted (edited)
7 minutes ago, John John said:

That is what Newton said about the apple but it pulls the Earth up just a little bit.

It's better to stick to the General Relativity version. Although not wrong within its domain of applicability, it will get you to the Moon, GR explains it more completely. Even GR has a domain of applicability, and we know now it is not complete. It's more than adequate for us amateurs.

Edited by StringJunky
Posted
3 minutes ago, StringJunky said:

It's better to stick to the General Relativity version. Although not wrong within its domain of applicability, it will get you to the Moon, GR explains it more completely.

It is amazing how much energy is required to defeat the pull of the Earth and leave it behind.

Posted
1 hour ago, John John said:

it doesn't get us to the edge of the fiscal universe.

Perhaps we should ask an accountant. Do economies have edges? 

Fun fact: James Webb is an exceedingly common name for CPAs, but none of them has anything to do with the telescope under discussion here. 

Posted
1 minute ago, iNow said:

Perhaps we should ask an accountant. Do economies have edges? 

Sounds like inflation if we need an accountant. What I owe the tax man goes deeper than the universe.

Posted

As the universe is everything that suggests you owe nothing in taxes since nothing is deeper 

Posted
1 minute ago, iNow said:

As the universe is everything that suggests you owe nothing in taxes since nothing is deeper 

I never thought of that, thanks it a big load off my shoulders. I will let the tax man know the universe has taken care of my tax.

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