What is beyond the boundaries of our visible universe?

[dmill1220]

I did mean dark Energy, and not dark matter, I also meant to say that we need to phsyically detect it, Science requires proof and they will not stop until they find it, if its possible. So far our math seems to be on the right track but its extremely important to actually confirm dark energy instead of mathematically theorizing it right? I was watching a show on the science channel about the expanding universe where both of these theories were debated, I wish I could remember the name of the Cosmolgist that is the underdog with his varying gravitaional theory. I read about this some time ago in Astronomy Magazine, they even got into bubble Universe theories along with string theories, believe me Im no cosmologist, but we dont have all the answers yet, and those of us that think we do Are keeping a closed mind, which really stops the advancement of science.

as far as the Hindus, when I was in the army I met one while on Duty over seas, He explained to me that they believe that the universe goes thru Cycles that last a long period of time i cant remember what he called it but its where the universe expands seemingly for a long long time then it slows and contracts and then starts a whole new big bang then every instance of a new big bang has its own different laws of Physics sounds really wierd dosent it?
here is some food for thought that he gave me, we can only expierience with our senses right? but we know that there is alot more to the universe that what we can see, things that only our instruments or computer simulations alow us to concieve, every time we look with better instruments or with new mathematics we find more questions. I guess what im trying to say is we are a long way from knowing it all. Maybe Ockhams Razor isnt the right approach?
I dont pretend to know or even guess at this since we are only limted by our senses, I just choose to keep an open mind and sit back take everything in that I can and learn and wonder at how truly an amazing time we live in.
Dennis

[Blue Fire]

Originally Posted by dmill1220

I did mean dark Energy, and not dark matter, I also meant to say that we need to phsyically detect it, Science requires proof and they will not stop until they find it, if its possible. So far our math seems to be on the right track but its extremely important to actually confirm dark energy instead of mathematically theorizing it right?

Agreed.

believe me Im no cosmologist, but we dont have all the answers yet, and those of us that think we do Are keeping a closed mind, which really stops the advancement of science.

No argument here either, really. But I might add that there are those too that will stand at the fork in the road and forever debate which way is the right way without stepping forth. Often, in science, to get anywhere at all we have to just pick one road, see where it leads, and turn around and go back to the fork in the road and try the other one if the first road turns out to be a dead end.

as far as the Hindus, when I was in the army I met one while on Duty over seas, He explained to me that they believe that the universe goes thru Cycles that last a long period of time i cant remember what he called it but its where the universe expands seemingly for a long long time then it slows and contracts and then starts a whole new big bang then every instance of a new big bang has its own different laws of Physics sounds really wierd dosent it?

The big bang/big crunch scenario, perhaps with a twist of new laws of physics. Also reminds me of some some incarnations of Eternal Return as developed by Nietzsche.

here is some food for thought that he gave me, we can only expierience with our senses right? but we know that there is alot more to the universe that what we can see, things that only our instruments or computer simulations alow us to concieve, every time we look with better instruments or with new mathematics we find more questions. I guess what im trying to say is we are a long way from knowing it all. Maybe Ockhams Razor isnt the right approach?
I dont pretend to know or even guess at this since we are only limted by our senses, I just choose to keep an open mind and sit back take everything in that I can and learn and wonder at how truly an amazing time we live in.

As I understand it, I generally put stock in Ockham's Razor in so far as it advocates simplicity and simplification. My own pet theory is that any ultimate truths or TOE or GUT will turn out to be much simpler than we have so far been able to determine. I think technological progress only really happens when we learn to simplify. Like finally learning to fly under our own power alone (I think it was the pedal powered Gossamer Butterfly or something) across the English Channel only after inventing the increasing complexity of airplanes and jets and rockets and spacecraft to carry us to the Moon. Also like going through steam engines, electric engines, combustion engines and nuclear powered engines only to finally make a jump to something simpler like solar power. Especially when you consider that even nuclear generators just use a different fuel to heat water to make steam to turn a turbine to generate electricity.

[dmill1220]

As I understand it, I generally put stock in Ockham's Razor in so far as it advocates simplicity and simplification. My own pet theory is that any ultimate truths or TOE or GUT will turn out to be much simpler than we have so far been able to determine. I think technological progress only really happens when we learn to simplify. Like finally learning to fly under our own power alone (I think it was the pedal powered Gossamer Butterfly or something) across the English Channel only after inventing the increasing complexity of airplanes and jets and rockets and spacecraft to carry us to the Moon. Also like going through steam engines, electric engines, combustion engines and nuclear powered engines only to finally make a jump to something simpler like solar power. Especially when you consider that even nuclear generators just use a different fuel to heat water to make steam to turn a turbine to generate electricity.

I defintely Agree with you !
But I have seen situatons, especially in my past engineering experience, were the simplest answer was the incorrect one.
but Im still with you!

I believe I remember what the Hindu cycles were called, I think they were called Bramas. although an interesting idea, I dont really follow this line of thinking.
Dennis

[Dragon Star]

Holy cow...well, too much has been said for me to pick apart everything and elaborate, so I am just going to state a few things for reference.

First of all, Dark Energy is only a hypothetical form of energy which permeates all of space and has strong negative pressure.

We have 2 problems, the fact that the universe appears to be expanding at an accelerating rate, and that we have HUGE missing amounts of mass in the universe...Dark Energy, hypothetically, accounts for this. So in fact, we do observe directly the effects of Dark Energy.

There are 2 proposed forms of Dark Energy, the cosmological constant, a constant energy density filling space homogeneously, and quintessence, a dynamic field whose energy density can vary in time and space. Quintessence has yet to be proven, but can't be thrown away yet because it explains the start of expansion after inflation. Both of them account for almost all observations and measurements. The total amount of matter in the Universe (including baryons and dark matter), as measured by the CMB, accounts for only 30% of the critical density, which implies the existence of an additional form of energy to account for the remaining 70%.

I believe I remember what the Hindu cycles were called, I think they were called Bramas. although an interesting idea, I don't really follow this line of thinking.

Good call, just a little off.

http://en.wikipedia.org/wiki/Hindu_C...f_The_Universe

What you are describing is the Multiverse, I won't expand on that much because you can go on for days about that, if you are interested you can ask in Q&A or make a dedicated thread for the topic.

It is actually a good theory, I personally like it.

[dmill1220]

From what I understand and please correct me if Im wrong, but havent we only observed Dark Energies effects and not actually detected what its made up of?
As I understand our present knowledge of dark Energy, there are three competing explanations or theories
1} the Cosmological Constant,
2}Quintessence
3} Illusion
with the third, illusion, bieng a breakdown of Einsteins theory of gravity in large scales, the gravity theory that I was referring to.
And Quintessence, bieng some kind of unidentified energy field in space.
Please enlighten me as I love to learn about this stuff!
Im so far behind in this that its sad.
another question, have scientist absolutely solved the redshift competing theories I think that I read somewhere that there was some kind of debate as to the accuracy of the doppler effect especially if dark energy has'nt been completley identified, could this exotic effect have an adverse reaction to the Photon energies over a large distance scale?
Im really not up much on Cosmology or Particle Physics.
Dennis

[Dragon Star]

The two leading models are quintessence and the cosmological constant. Other ideas for dark energy have come from string theory, brane cosmology and the holographic principle, but have not yet proved as compelling as quintessence and the cosmological constant.

Dark Energy is not very dense—roughly 10^−29 grams per cubic centimeter, which is VERY hard to detect with experiments in a laboratory...and this is why there is no direct observation. But regardless, it's real in physics, because without it there is no universe, and there is no us in any current mainstream models of the universe.

have scientist absolutely solved the redshift competing theories I think that I read somewhere that there was some kind of debate as to the accuracy of the doppler effect especially if dark energy has'nt been completley identified, could this exotic effect have an adverse reaction to the Photon energies over a large distance scale?
Im really not up much on Cosmology or Particle Physics.

Not real strong in this area, but as far as I know Dark Energy has nothing to do with Doppler effect, as far as it is only the observation of a source of the light is moving away from an observer, which is in return caused by Dark Energy and cosmological expansion. Except for the exceptions given to special motions (e.g. Andromeda / Milky Way).

By that I mean that Dark Energy can only make Doppler Effect greater or weaker, as it is expressed in a formula. So I don't really see what you are getting at here...if you could expand a bit about what you mean precisely it would help.

[Dragon Star]

Sorry, just noticed something...

Originally Posted by dmill1220

From what I understand and please correct me if Im wrong, but havent we only observed Dark Energies effects and not actually detected what its made up of?

Um, energy?

[dmill1220]

Hi Dragon!
please check out the Sept issue of Astronomy, according to the article they are giving alot of weight to the 3rd, ILLUSION.
on page 32, the article says that the modified theory of gravity the 3rd theory, deserves serious consideration, according to at least Princetons University, David Spergel and others.

As far as the red shift problem, they seem to be using the redshifts of Supernovas, the standard candles, as a measurement of expansion.
here is were my lack of knowledge on this subject and particle physics, confuses me, if we do not know what dark energy is made up of, how can we be so sure that it has'nt thrown off these measurements, or interacted somehow to distort the redshifts? since its obviously a unknown force, it has to be made up of something? or am I way off here? did we also identify what gravity is made up of also? have we proved the existence of gravitons or something similiar?
Now im really confused! I thought we were still trying to detect gravity waves or particles, and if so, and we do not know what kind of particles or waves, makes the effects of dark energy, how can they come to any concrete conclusions with the redshift principle if they have not answered these two questions? wow! ! think I just made myself dizzy, and believe me it does'nt take much!
Please enlighten my feeble mind Master!
Dennis

[Dragon Star]

Originally Posted by dmill1220

Hi Dragon!
please check out the Sept issue of Astronomy, according to the article they are giving alot of weight to the 3rd, ILLUSION.
on page 32, the article says that the modified theory of gravity the 3rd theory, derserves serious consideration, according to at least Princetons University, David Spergel and others.

OK, I am going to put this simply, without Dark Energy, we have no hubble constant, and no expansion after inflation. AKA, big crunch/bounce. Dark Energy is the driving power of the universe, so to say it is an illusion is to say that cosmological expansion is an illusion, in which case I will call you a woo-woo.

As far as the red shift problem, they seem to be using the redshifts of Supernovas, the standard candles, as a measurement of expansion.

Yep.

here is were my lack of knowledge on this subject and particle physics, confuses me, if we do not know what dark energy is made up of, how can we be so sure that it has'nt thrown off these measurements, or interacted somehow to distort the redshifts?

Okay, that is the kind of question I was looking for. Redshift occurs as an object moves away relative to us. Now comes Blue-shift, which occurs when objects are moving closer relative to us. Now, if the universe were contracting, everything would be blueshifted instead of red-shifted.(I know you knew that, but for the readers out there that don't...) And as far as anyone knows this is full-proof, and can't be changed by space one way or the other in any significant way. Dark energy is a very weak energy, but it has so much effect because there is so much of it, without it being as much as it is we would have very different outcomes of the universe. So my conclusion is that Dark Energy can't have any significant effect on the length of a photon wave, even on large scales. Something that we can't even detect likely isn't going to affect matter much in any way.

since its obviously a unknown force, it has to be made up of something?

Again, its not a force, it's energy, and energy is just that, energy. Energy can have properties (e.g. for Dark Energy is strong negative pressure) but they don't have physical characteristics as you appear to think.

did we also identify what gravity is made up of also?

Lord no, we don't even know if we have gravity right, there are lots of holes in that theory, but it just has to do for now...but it's probably wrong.

have we proved the existence of gravitons or something similiar? Now im really confused! I thought we were still trying to detect gravity waves or particles,

No. Detecting a graviton, if it exists, would prove rather problematic. Because the gravitational force is so incredibly weak, physicists are not even able to directly verify the existence of gravitational waves, as predicted by general relativity.

and if so, and we do not know what kind of particles or waves, makes the effects of dark energy, how can they come to any concrete conclusions with the redshift principle if they have not answered these two questions?

They have their ways, I just don't know all of them...I will do some research tomorrow and see if I can dig up anything on the methods used in detail and the flaws they contain so we have a better understanding.

wow! ! think I just made myself dizzy, and believe me it does'nt take much!
Please enlighten my feeble mind Master!
Dennis

MASTER? Oh no, not me...I don't know much. I deal mostly with theoretical physics, outside of that is just basic understanding. Go bark up KenG's tree at BAUT to find a master.

[Blue Fire]

Good exchange between dmill1220 and dragon star! Good questions and aswers - I always appreciate these since I learn a lot from just lurking around and watching the action. Thanks to both of you!