Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 12/03/2012 08:57:01

Title: Are there limits to what we can comprehend about the Universe?
Post by: thedoc on 12/03/2012 08:57:01
Manogrie Golden  asked the Naked Scientists:
   
Hi there,

We have evolved to deal with the environments in which we found ourselves.
Are there limits to what we can understand about the universe?
Are our brains and minds too limited to understand the real nature of the universe?

I hope not.

Many thanks for a great website,

Manoo Golden
Johannesburg, South Africa

What do you think?
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Æthelwulf on 12/03/2012 15:35:42
What do you mean by limits?

And as far as the mind-brain goes, I am in agreement with Susskind, that it was part of evolution that our brains could understand physics.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: MikeS on 12/03/2012 21:09:06
I think our only limit is with knowledge and that increases daily.  Through language and writing etc. that knowledge is built upon by subsequent generations, hopefully without end.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Soul Surfer on 13/03/2012 10:54:20
An interesting question.  We can clearly only understand things that we can obsere and infer from observations and models based on observations.  If there are aspects of the universe that are outside of both of these possibilities we can never comprehend them but on the other hand they can never affect us because if they did we could observe the effect.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: graham.d on 13/03/2012 17:21:52
I think it depends on what you mean by "understand". I don't think any physicist would say he really understands aspects of modern physics. He/she may be able to do the maths, and use this to make predictions in some areas, but is this the same as understanding the subject? All of deep physics is based on theoretical models which, as Prof Lisa Randall says, we can grasp only through the maths or, sometimes, by analogy and explain verbally. Maybe are brains are not wired to understand the concepts - they cannot be visualised except by limited analogies. But this does not stop some people from being able to be so good at this they do develop some intuition about how the universe may behave, but it is an interesting philosophical point about whether this constitutes true understanding. I suppose string theory is a good example - the models work to a large extent but nobody really knows whether the idea of a "string" has any meaning in reality except as a visualisation that we can assign familiar qualities to. It is possible, in reality, that this concept is just the nearest we can get to a model that we can grasp.

But then do we really "understand" anything?


Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Æthelwulf on 13/03/2012 19:01:17
I still think the larger part of our understanding of the universe is mostly biological itself - that intellect is a product of natural selection. I think Susskind is right - but perhaps what he did not realize was that if this was to be true, then nature emerges itself with the intent of creating life; it does afterall bring us back to not only an age-old question, but one Susskind has dedicated most of his life to, the question of the strong anthropic theory, the idea there is an intelligence behind the universe at large - one maybe us mere intellects may call ''God'' - but those who did might consider such as the trailor trash of intelligence.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: yor_on on 14/03/2012 04:22:30
Nah, we're here to see ourselves :)
And to do it we had to invent a arrow.

We're pretty smart me thinks.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Don_1 on 14/03/2012 09:46:18
I have to subscribe to Graham's last sentence, "But then do we really "understand" anything?"

Here we are theorising all over the place. 'Quarks', 'black holes', 'dark matter', 'event horizons', 'singularities', the 'Higgs Boson', the 'Big Bang' etc etc etc. But do we understand them? Do they even exist?

At the moment, I think our knowledge is limited; good grief, let's face it, we have only been looking at the universe with something slightly better than the naked eye for a few hundred years and only in the past 50 or so with anything substantially better than a mere nautical telescope.

The theories we have now could be way off the mark. So I think it far too early to start wondering whether or not we can ever understand all there is to know and much of what we may 'learn' over the coming millennia may only be taken as 'fitting in' with other theories.

But if there is one thing I think we can never understand, it is 'infinity'.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: imatfaal on 14/03/2012 09:59:19
I have to subscribe to Graham's last sentence, "But then do we really "understand" anything?"

Here we are theorising all over the place. 'Quarks', 'black holes', 'dark matter', 'event horizons', 'singularities', the 'Higgs Boson', the 'Big Bang' etc etc etc. But do we understand them? Do they even exist?

At the moment, I think our knowledge is limited; good grief, let's face it, we have only been looking at the universe with something slightly better than the naked eye for a few hundred years and only in the past 50 or so with anything substantially better than a mere nautical telescope.

The theories we have now could be way off the mark. So I think it far too early to start wondering whether or not we can ever understand all there is to know and much of what we may 'learn' over the coming millennia may only be taken as 'fitting in' with other theories.

But if there is one thing I think we can never understand, it is 'infinity'.
Funny - I think it is the other way around.  Mathematical concepts are the one thing we can actually understand - all we can do with physical concepts is to model them.  I think it is physics dirty secret that there is a huge amount of "who cares if it's true, or if we can comprehend it - as long as the model works" - the different interpretations of qm are a prime example. fields and gauge bosons are a second.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: yor_on on 14/03/2012 14:38:35
Yeah, it's the old quandary. Does mathematics mirror nature just by being built the way it is? Or is it primarily a tool that you need to adapt to what we see and measure? And as we now a days seem to love weak measurements, are the conclusions we can draw from statistical behavior fitting, for example a 'photon path'?

It would be nice if mathematics, when done properly, is a 'universal language', but it seems to assume an awful lot. It's also about the old linear way we're used to look at things, from the arrow to causality chains. The linearity is baffling to me, as it seems interwoven with non linear behavior as if Nature created reality layers on layers?
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Manoo on 15/03/2012 17:41:50
Hey, thanks for posting my question!

Notwithstanding the philosophical aspects to the question (i.e., are our theories getting closer to describing the 'reality'/'truth' and would ever be able to develop a model that accurately describes the universe?); my issues were around concepts.

For example, if we say that space/time is a property of this universe, can we conceive of a universe in which is not a property?

Or, indeed, develop a model of a universe with a different set of laws of physics/nature (M-theory posits that we are just one universe in a whole infinite number of possible universes that could have very different properties).

Or try to comprehend 11 spatial dimensions when we only can "know" three (and only through mathematics conceive of others).

What about concepts such as infinity, where, if there are infinite numbers of universes, it is possible to repeat a configuration of matter and have exactly another universe/solar system where we exist, making the same or different decisions?

We have evolved to survive here, in this corner of the solar system, and we have done remarkably well in understanding our corner. Thus, my question, is it possible that we just might be limited to that (and maybe a bit beyond it)?
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: MikeS on 15/03/2012 19:57:48
Manoo

I don't think it is possible to have a universe without either space or time therefore they would seem to me to be basic qualities of any universe.

Personally I am inclined to believe that the laws of physics/nature are probably the same in any universe.  My reason being, we believe the Universe developed from a very simple and organised set of initial conditions  (There was lots of energy and it was hot).  If this is correct then the factors that caused our Universe to develop the way it did would seem to apply to any other developing universe.  I can say this without any shadow of a doubt as we will never know. :)
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: yor_on on 16/03/2012 19:20:16
Well, we're already 'there' Manoo :)
A quantum computer is something without 'time', as for the concept of 'space'?
I don't know what 'space' is myself?

Locally you can define it. Universally you need 'transformations' of those local definitions to find your 'conceptual' truth.
Where do I define reality?

I do it locally.
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Manoo on 16/03/2012 19:44:38
Yup, I also don't know what exactly 'space' is...
Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Airthumbs on 16/03/2012 21:34:49
I think this is a fascinating question which is also something of an evolving question.  As science moves forward we are able to create better sensory devices.  We, as humans, cannot see Infra Red or Ultra Violet, and as for the Cosmic Microwave Background, we would never have a reason to evolve where it would be beneficial to sense it.

With further developments in digital technology and the speed at which data can be processed we are already far beyond what we could ever imagine or achieve without these devices we have created. 

Our brains are very open to new discoveries, in fact we even seem to seek out new discoveries as a driving force of our nature.  By using our extra sensory devices we have uncovered many deep mysteries that have been questions since the dawn of language. 

As long as we have a language to communicate anything in our imagination I do not see why we could not comprehend anything in the Universe. 

I feel the only limit to our further comprehension of the Universe is technology.

Title: Re: Are there limits to what we can comprehend about the Universe?
Post by: Soul Surfer on 17/03/2012 10:08:42
The Quantum mechanical vacuum is described in terms of every possible state in every possible dimension existing for all time and any outcome is based on probabilities all the way down to times spaces and times as small and short as the planck limit.  There are clearly vast numbers of very brief and (physically) small probabilities.  For something like a "universe"  to exist there must be some sort of coherent behaviour that evolves and changes in some way rather than just random noise.

When you add this requirement you start to limit the dimensionality that is available and require via Noethers theorem some simple conservation laws.  Considerable research in this area show that for a persistent structure three dimensions of "space" and one of "time"  OR!  three dimensions of "time" and one of "space"  together with the conservation of energy momentum and angular momentum are the only ones that produce long lived recycling structures.