Photon?

[Farsight]

Quantum_wave: be wary of stuff like this:

The big difference between the black hole and the early universe is that a black hole sits in a region where its gravity can overcome the expansion rate of the scale factor. In the early universe, the scale factor is expanding so rapidly that the immense energy density of the universe cannot slow it enough to create something like a black hole.

Because it's tosh. A gravitational field is a place where there's an energy-pressure gradient in space. It alters the motion of light and matter through that space. But it doesn't make that space fall inwards. The Earth's gravitational field isn't making the sky fall in. We do not live in a Chicken-Little world. The black hole "waterfall analogy" is popscience rubbish for kids, peddled by people who don't understand general relativity at all. It doesn't matter whether you have an energy-pressure gradient in space or not, you still have pressure in that space, and it's still going to expand. Even if it's superdense. It just isn't going to contract.

Sadly Einstein used dust instead of space itself in his cosmological modelling, then introduced his cosmological constant because he was convinced that the universe was static. It's as if his confidence in his own theory deserted him. He should have predicted the expanding universe long before Hubble found that galactic redshift increased with distance.

 

[PhysBang]

Thanks for all of that. It becomes AltTheory very quickly. My point was that your model has no explanation for the beginning or the preconditions. Any scenario of preconditions violates the model; so does that mean that there can be no explanation for the existence of the universe that doesn't falsify spacetime?

No, there are many scenarios that might lead to a universe like we have. Unfortunately, there is not yet enough evidence to support one.

 

[PhysBang]

Quantum_wave: be wary of stuff like this:
Because it's tosh.

Sure. Why don't you go through the mathematics of one of the many papers on the nature of the early universe and show us the problem? You are the "physics expert" , so unless you are lying, you should be able to show us the errors in detail.

gravitational field is a place where there's an energy-pressure gradient in space. It alters the motion of light and matter through that space. But it doesn't make that space fall inwards. The Earth's gravitational field isn't making the sky fall in. We do not live in a Chicken-Little world. The black hole "waterfall analogy" is popscience rubbish for kids, peddled by people who don't understand general relativity at all. It doesn't matter whether you have an energy-pressure gradient in space or not, you still have pressure in that space, and it's still going to expand. Even if it's superdense. It just isn't going to contract.

Even if this was the case, it doesn't matter to the facts. a) You don't have a model for a black hole so you can't compare it to the early universe. b) Tje scale factor increase in the early universe vastly out paces the effect of gravity, even if it worked like you imagine it.

Sadly Einstein used dust instead of space itself in his cosmological modelling, then introduced his cosmological constant because he was convinced that the universe was static.

OK, so show us how to model cosmology using "space itself". Either you can produce a model or you are lying about being a "physics expert".

It's as if his confidence in his own theory deserted him. He should have predicted the expanding universe long before Hubble found that galactic redshift increased with distance.

Please, show us how your ideas predict redshift. The standard "dust" models predict redshift.

 

[quantum_wave]

Quantum_wave: be wary of stuff like this:
Because it's tosh. A gravitational field is a place where there's an energy-pressure gradient in space. It alters the motion of light and matter through that space. But it doesn't make that space fall inwards. The Earth's gravitational field isn't making the sky fall in. We do not live in a Chicken-Little world. The black hole "waterfall analogy" is popscience rubbish for kids, peddled by people who don't understand general relativity at all. It doesn't matter whether you have an energy-pressure gradient in space or not, you still have pressure in that space, and it's still going to expand. Even if it's superdense. It just isn't going to contract.

Sadly Einstein used dust instead of space itself in his cosmological modelling, then introduced his cosmological constant because he was convinced that the universe was static. It's as if his confidence in his own theory deserted him. He should have predicted the expanding universe long before Hubble found that galactic redshift increased with distance.

I believe that PhysBang is referring to the Standard Cosmological Model that starts after what ever event causes it or prededes it, i.e. he picks up picoseconds after the event. In that epic, superluminal expansion or inflation is taking place, and so in his model, regardless of the ratio of matter to space, there isn't enough matter to halt the inflation.

As for the energy-pressure gradient in space, I see it being real with some important specifications, but the circumstances in which it exists are not Big Bang related, at least not solely connected to the big bang. Preconditions, if we were to be able to discuss them here, might include a greater universe with an every changeing gravitational gradient imposed on the medium of space by the presence of matter.

 

[quantum_wave]

No, there are many scenarios that might lead to a universe like we have. Unfortunately, there is not yet enough evidence to support one.

And that is the truth. But many of the scenarios, and maybe the ones a layman might envision, might not be entirely consistent with a spacetime scenario where space emerged from a point.

 

[PhysBang]

Well, the current cosmological theory on the history of the known universe is consistent with there never being a first event. The universe could have grown from a very small region. We just can't look back that far, yet.

 

[quantum_wave]

Well, the current cosmological theory on the history of the known universe is consistent with there never being a first event. The universe could have grown from a very small region. We just can't look back that far, yet.

I'll give you that. It isn't satisfactory to me but I'm just a layman science enthusiast who wants there to be cause and effect. It may be just me, but something from nothing leaves us with a universe that we can't understand, that will end in the death of life, and where entropy is always increasing. There are scenarios that defeat entropy, that to a simple layman are more probable than something from nothing, if only because we are still here. We don't know the correct scenario, probably can't know for sure, so we are all in the same boat. If we want a more or less complete scenario, with explanations for things we cannot know, we have to take personal liberties with scenarios and hypotheses. Too bad we can't talk about them here.

 

[Farsight]

I believe that PhysBang is referring to the Standard Cosmological Model that starts after what ever event causes it or prededes it, i.e. he picks up picoseconds after the event. In that epic, superluminal expansion or inflation is taking place, and so in his model, regardless of the ratio of matter to space, there isn't enough matter to halt the inflation.

I reiterate, PhysBang is talking popscience nonsense. A gravitational field is a place where space is inhomogeneous. This alters the motion of light and matter through that space, it doesn't make space collapse inwards. Yes you can find plenty of references to "the big crunch", but it's all baloney. The whole problem with physics and cosmology is that you've got quacks and hacks peddling nonsense and trying to convince you that it's mainstream.

As for the energy-pressure gradient in space, I see it being real with some important specifications, but the circumstances in which it exists are not Big Bang related, at least not solely connected to the big bang.

Sure thing. Gravity is a piece of cake. The big bang isn't nearly so cut and dried.

Preconditions, if we were to be able to discuss them here, might include a greater universe with an every changeing gravitational gradient imposed on the medium of space by the presence of matter.

Discuss away. I won't be told what I can and can't discuss. By the way, see where PhysBang said this?

"The universe could have grown from a very small region".

If it did grow from a very small region in a finite time, it can't be infinite. And if it isn't infinite, and if it's flat like WMAP suggests, then it has to have some kind of edge. Like this.

 

[paddoboy]

I reiterate, PhysBang is talking popscience nonsense.

No, it's you talking pop science nonsense.
It's you making nonsensical claims, based on misinterpretations of what Einstein said and didn't say.

This alters the motion of light and matter through that space, it doesn't make space collapse inwards.

Light/Photons always travel at "c" FACT:
Light does not in itself "bend"....Light is following geodesics in curved spacetime. FACT:

The whole problem with physics and cosmology is that you've got quacks and hacks peddling nonsense and trying to convince you that it's mainstream.

Yet you have claimed to have a TOE? Was that true or false? Were you just trying to impress after being rejected by so many?

Discuss away. I won't be told what I can and can't discuss.

Yes you most certainly will, in the appropriate section, which is why you have had threads shifted to the fringe.

"The universe could have grown from a very small region".

The Universe evolved from a hot dense state we call the BB.

If it did grow from a very small region in a finite time, it can't be infinite. And if it isn't infinite, and if it's flat like WMAP suggests, then it has to have some kind of edge. Like this.

That is total crap. All Flat entails is geometry. It says the Universe over large scales is flat..that is two beams of light emitted from a source parallel, will remain parallel...If the Universe was closed, those beams would converge...if it was open, they would diverge.

For someone claiming to have a TOE, [nudge, nudge, wink, wink ] you certainly are ignorant of cosmology.

Another misconception you have been spraying about...just because the Universe is expanding, does not in anyway contain whether it is finite or infinite.
http://www.astro.ucla.edu/~wright/infpoint.html

 

[PhysBang]

I reiterate, PhysBang is talking popscience nonsense.

Sure. Everything about modern science is nonsense to you because you won't learn math.

A gravitational field is a place where space is inhomogeneous.

If this is the case, then please show us a way to do a physics problem with your inhomogeneous space.

Any cosmology textbook shows how to work out the gravitational effects of a homogeneous distribution in space time (a distribution which is, of course, only homogeneous using certain systems of coordinates and not others, but Farsight can't understand that since he doesn't know SR or GR).

The whole problem with physics and cosmology is that you've got quacks and hacks peddling nonsense and trying to convince you that it's mainstream.

If this is the case, you should be able to point out an actual problem with the science rather than simply parroting your one line over and over again. Yet you can never show anyone how to do any physics with your one line.

Sure thing. Gravity is a piece of cake.

Ok, so show us how to do a simple gravity problem with inhomogeneous space.

Discuss away. I won't be told what I can and can't discuss.

But we all know that you can't discuss the details of physics because you don't know them.

By the way, see where PhysBang said this?

"The universe could have grown from a very small region".

If it did grow from a very small region in a finite time, it can't be infinite. And if it isn't infinite, and if it's flat like WMAP suggests, then it has to have some kind of edge. Like this.

Well, it's good to see idiocy supported with a reference to idiocy.

Yes, if the universe began as a finite volume, then it must be finite now. No, it doesn't have to have an edge. This is something that people realized over a century ago that Farsight hasn't caught up with yet.

Here's a nice video explaining finite spaces without edges.

(Fun fact: The maker of the video recommends a website for further reading and the forums for that website banned Farsight because he wouldn't answer questions about the details of his physics proposals. Years ago.)

 

[paddoboy]

Quantum_wave: be wary of stuff like this:
Because it's tosh. A gravitational field is a place where there's an energy-pressure gradient in space. It alters the motion of light and matter through that space. But it doesn't make that space fall inwards. The Earth's gravitational field isn't making the sky fall in. We do not live in a Chicken-Little world. The black hole "waterfall analogy" is popscience rubbish for kids, peddled by people who don't understand general relativity at all. It doesn't matter whether you have an energy-pressure gradient in space or not, you still have pressure in that space, and it's still going to expand. Even if it's superdense. It just isn't going to contract.

More nonsensical child like views of cosmology, by the forum's own Hans Christian Anderson.....
Let me explain more correctly, and prove that Farsight is again spouting nonsense.
We know for certain that over large scales the Universe is expanding.
Yet we also know that M31 which is 2.5 million L/years away, is moving along with the MW and the rest of the local group, towards one another.
How can this be?
Simply put, without any Farsight bullshit, the mass/energy density of local regions, such as our local group of galaxies and even beyond to our local cluster and wall of galaxies, create a spacetime curvature or gravity, that overcomes the overall expansion rate.

It's like in many ways to a fish swimming upstream at 10kms/hour, against the streams current of 15kms/hour.
Obviously the fish is not going to make much progress.

Extending on that picture somewhat, the future of our cosmology, in a few billion years, will be rather bare. All we will be able to view with our instruments, is our own galaxy, a merger of the MW, LMC, SMC, M31 Triagulum and a few others.
All other distant galaxies will be shifted beyond our viewable horizon.

 

[quantum_wave]

I reiterate, PhysBang is talking popscience nonsense. A gravitational field is a place where space is inhomogeneous. This alters the motion of light and matter through that space, it doesn't make space collapse inwards.

Where are you getting that scenario about collapsing space. Did I miss where PhysBang said that?

Yes you can find plenty of references to "the big crunch", but it's all baloney. The whole problem with physics and cosmology is that you've got quacks and hacks peddling nonsense and trying to convince you that it's mainstream.

Maybe so, but I've had worse said about me. My model does include the convergence of two or more parent Big Bang arenas, and the galactic material from each swirls into a "Big Crunch". The crunch is composed of galactic material captured by gravity in the overlap space as the parent arenas converge. But the convergence does not halt the generally spherically expansion of the parent arenas. They continue to expand, and that causes more and more of their galactic material into the overlap space where the crunch forms at the center of gravity.

I actually have an equation that quantifies the relative radii of the converging parent arenas at the point in time where the crunch supposedly reaches critical capacity and collapses/bangs into a new Big Bang arena. I think it is in this old thread. The convergence applies to individual "quanta" within a particle, and to Big Bang arena waves that hypothetically make up the landscape of the greater universe: http://www.sciforums.com/threads/quantifying-gravitys-mechanism.134207/

The scenario is not a multiverse though, it is more than one big bang arena, i.e. multiple Big Bang arenas within one greater universe.

...
Discuss away. I won't be told what I can and can't discuss.

Sure, except you won't come out to the fringe where some of the discussions of alternative ideas take place. When my threads start there few come to chat, and when threads are moved, the members don't often follow them out there. Not enough active members interested in alternative cosmology anymore.

By the way, see where PhysBang said this? "The universe could have grown from a very small region".

If it did grow from a very small region in a finite time, it can't be infinite. And if it isn't infinite, and if it's flat like WMAP suggests, then it has to have some kind of edge. Like this.

I did see where he said that. I know what you mean, you can't have both spatially infinite and growing/expanding curved spacetime, unless you can explain the contradiction.

 

[paddoboy]

, you can't have both spatially infinite and growing/expanding curved spacetime, unless you can explain the contradiction.

http://www.astro.ucla.edu/~wright/infpoint.html


At this stage of the game, the evidence says the Universe is accelerating in its expansion rate, is flat, and most likely infinite.
From what little I do know, the finite/Infinite debate still appears to be wide open.

 

[quantum_wave]

http://www.astro.ucla.edu/~wright/infpoint.html


At this stage of the game, the evidence says the Universe is accelerating in its expansion rate, is flat, and most likely infinite.
From what little I do know, the finite/Infinite debate still appears to be wide open.

Thanks for the link. I have some questions and comments about it, but will let them go, given the aversion to alternative discussions.

 

[krash661]

Well, it's good to see idiocy supported with a reference to idiocy.

http://www.imdb.com/title/tt0387808/

 

[James R]

Farsight,

Einstein gave most of the "how" of it, but people dismiss Einstein and come out with cargo-cult popscience nonsense like light follows geodesics in curved space time. This is wrong on so many counts. For example, curved spacetime relates to the second derivative of potential, and tidal force. The force of gravity depends on the spacetime "tilt" which is the first derivative of potential.

In the GR picture, gravity is not a force.

It is correct to say that light follows geodesics in spacetime. Nothing you have written above shows that this is an incorrect statement. You can quibble with the word "follows" if you like, based on the notion that spacetime is a static entity. But the fact remains that if you plot the path of a photon through spacetime, you get a geodesic. Not that geodesics are limited to photons, of course.

Permeability. Permittivity is like "how easy is it to bend space". Permeability is like "how strong it bounces back".

Show me how you reached that conclusion, including appropriate equations.

A light wave is a "pulse" of energy propagating through space at c, whatever c is. Again it's like you inject space into space. The photon has a gravitational field. IMHO the best way to think of this is to say the photon's gravitational field is the reaction to action h in E=hf.

Please explain in more detail - especially the point about Planck's constant.

Einstein said the speed of light varied where a gravitational field is, and we know all about the "coordinate" speed of light being zero at the event horizon. So that's a place where time stops.

We've already been through this. The speed of light is c at the event horizon, not zero. It's only different from c if you try to measure it non-locally. And that goes for any measurement of the speed of light anywhere (not just near a black hole).

You claim that the speed of light varies between the floor and ceiling of your room. Recently, you even provided a link to a John Baez article that explains this. But it looks like you didn't read it, or else you didn't understand it. If you measure the speed of light at the ceiling, it will be c. If you measure it on the floor, it will be c. It's only when you try to calculate the speed of light at the ceiling from your position on the floor that you will get something other than c.

I think your main point of confusion on the whole varying speed of light thing is that you don't carefully distinguish local measurements from non-local calculations.

 

[paddoboy]

I think your main point of confusion on the whole varying speed of light thing is that you don't carefully distinguish local measurements from non-local calculations.

From the many times I have crossed swords with him in the past, he appears not to accept the validity of the reality of all FoR's.
And yet he continues to quote/misquote Einstein.

 

[Farsight]

Where are you getting that scenario about collapsing space. Did I miss where PhysBang said that?

It's the waterfall analogy. You can find plenty of references to it on what look like reliable websites. Here's an example.

Maybe so, but I've had worse said about me. My model

Try not to be a "my theory" guy. You might think I am, but note that I'm forever referring to Einstein or Minkowski or Maxwell et cetera.

does include the convergence of two or more parent Big Bang arenas, and the galactic material from each swirls into a "Big Crunch". The crunch is composed of galactic material captured by gravity in the overlap space as the parent arenas converge. But the convergence does not halt the generally spherically expansion of the parent arenas. They continue to expand, and that causes more and more of their galactic material into the overlap space where the crunch forms at the center of gravity.

But there's no evidence to support this speculation.

I actually have an equation that quantifies the relative radii of the converging parent arenas at the point in time where the crunch supposedly reaches critical capacity and collapses/bangs into a new Big Bang arena. I think it is in this old thread. The convergence applies to individual "quanta" within a particle, and to Big Bang arena waves that hypothetically make up the landscape of the greater universe: http://www.sciforums.com/threads/quantifying-gravitys-mechanism.134207/

The trouble with physics is that people get attached to an idea which rumbles on for decades even though there's no supporting evidence.

The scenario is not a multiverse though, it is more than one big bang arena, i.e. multiple Big Bang arenas within one greater universe.
Sure, except you won't come out to the fringe where some of the discussions of alternative ideas take place. When my threads start there few come to chat, and when threads are moved, the members don't often follow them out there. Not enough active members interested in alternative cosmology anymore.

For myself I'd rather talk about the things that are out there and try to understand them before getting into "alternative cosmology".

I did see where he said that. I know what you mean, you can't have both spatially infinite and growing/expanding curved spacetime, unless you can explain the contradiction.

And people can't. Which says to me that the universe just can't be infinite. Only when you talk to a cosmologist about that, he seems to have some kind of mental block.

 

[paddoboy]

It's the waterfall analogy. You can find plenty of references to it on what look like reliable websites. Here's an example.

Quite a handy analogy actually, remembering that all analogies have limitations. Certainly far better then any frozen chook or time passing through a clock analogies.

Try not to be a "my theory" guy. You might think I am, but note that I'm forever referring to Einstein or Minkowski or Maxwell et cetera.

And you are forever cherry picking and misquoting....Here's an example. You say you quote Minkowsky, yet you ignore his extract from a popular address.
"The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality. – Hermann Minkowski, 1908"

The trouble with physics is that people get attached to an idea which rumbles on for decades even though there's no supporting evidence.

And yet you are forever quoting/misquoting 100 year old extracts about what Einstein said, and ignoring the science that has advanced SR/GR since those times

And people can't. Which says to me that the universe just can't be infinite. Only when you talk to a cosmologist about that, he seems to have some kind of mental block.

That's an opinion, and that's all it is.
best evidence shows us an accelerating expanding, flat Universe that is infinite in extent.
http://www.astro.ucla.edu/~wright/infpoint.html

 

[paddoboy]

Thanks for the link. I have some questions and comments about it, but will let them go, given the aversion to alternative discussions.

Just to add.....The BB is about the Universe/spacetime, evolving from a hot dense state. This hot dense state, this Singularity and all aspects which apply to it is unknown, Which leaves open logically the question of infinity, and which is why I was coached by a well respected knowledgable GR theorist, to describe the BB as an evolution of space and time [spacetime] as we know them.