An Infinite Past?

[Tassman]

Yes, but we have actual physical evidence for Higgs Boson and Black Holes now. Theories are all very fine but without physical evidence they will forever remain merely concepts or ideas. So again until you have said evidence Craig is perfectly justified in assuming God. You certainly can assume nature, but it too remains an assumption.

And like I posted before the whole inflation/multiverse theory may be fundamentally flawed:

http://www.physics.princeton.edu/~steinh/0411036.pdf

Inflation/multiverse theory may be shown to be fundamentally flawed, just as the predicted Higgs Boson may have been shown to be flawed. But there were solid reasons for predicting its existence just as there are good reasons for predicting the whole inflation/multiverse scenario. These theories are not just pulled out of a hat. Merely digging up links which raise questions about it does not alter the fact that the overall direction of cosmology is inflationary/multiverse theory. And for good reason!

[seer]

Inflation/multiverse theory may be shown to be fundamentally flawed, just as the predicted Higgs Boson may have been shown to be flawed. But there were solid reasons for predicting its existence just as there are good reasons for predicting the whole inflation/multiverse scenario. These theories are not just pulled out of a hat. Merely digging up links which raise questions about it does not alter the fact that the overall direction of cosmology is inflationary/multiverse theory. And for good reason!

Sure Tass, but the proof is in the pudding. As Steinhardt shows in the link there are very good reasons to doubt inflation theory. That it doesn't or can't explain what we see in this universe. And Steinhardt is no novice in this game, he was one of the original fathers of inflation theory. And just because a theory is popular doesn't make it right, Steinhardt makes this point in the link, that most cosmologists really don't even understand inflation theory. And if you are a materialist you want there to be a physical explanation for this universe, you are bias towards that end.

[shunyadragon]

Inflation/multiverse theory may be shown to be fundamentally flawed, just as the predicted Higgs Boson may have been shown to be flawed. But there were solid reasons for predicting its existence just as there are good reasons for predicting the whole inflation/multiverse scenario. These theories are not just pulled out of a hat. Merely digging up links which raise questions about it does not alter the fact that the overall direction of cosmology is inflationary/multiverse theory. And for good reason!

Very good explanation! There remains the poor understanding by layman of the limits of models and theorems involving the nature of our physical existence beyond our universe, but yes the current overall direction of cosmology is inflationary?/multiverse. I consider the timeless/dimensionless multiverse a good candidate.

[Tassman]

Sure Tass, but the proof is in the pudding. As Steinhardt shows in the link there are very good reasons to doubt inflation theory. That it doesn't or can't explain what we see in this universe. And Steinhardt is no novice in this game, he was one of the original fathers of inflation theory. And just because a theory is popular doesn't make it right, Steinhardt makes this point in the link, that most cosmologists really don't even understand inflation theory. And if you are a materialist you want there to be a physical explanation for this universe, you are bias towards that end.

[seer]

Very good explanation! There remains the poor understanding by layman of the limits of models and theorems involving the nature of our physical existence beyond our universe, but yes the current overall direction of cosmology is inflationary?/multiverse. I consider the timeless/dimensionless multiverse a good candidate.

And you Shuny know more about this than Dr. Steinhardt one of the fathers of inflationary theory? To quote:

The idea is so compelling that cosmologists, including me, routinely describe it to students, journalists and the public as an established fact. Yet something peculiar has happened to inflationary theory in the 30 years since Guth introduced it. As the case for inflation has grown stronger, so has the case against. The two cases are not equally well known: the evidence favoring inflation is familiar to a broad range of physicists, astrophysicists and science aficionados. Surprisingly few seem to follow the case against inflation except for a small group of us who have been quietly striving to address the challenges. Most astrophysicists have gone about their business testing the predictions of textbook inflationary theory without worrying about these deeper issues, hoping they would eventually be resolved. Unfortunately, the problems have resisted our best efforts to date.

[seer]

There is no doubt of a physical explanation for the universe, including Steinhardt’s. The only question is which one.

No doubt Tass? Where is the evidence for your belief?

Still no evidence...

[shunyadragon]

And you Shuny know more about this than Dr. Steinhardt one of the fathers of inflationary theory? To quote:

Where does mu view differ from that od Dr. Steinhardt. What you cited is ok, but not complete. I agreed that the inflationary/multiverse is the current most widely accepted view of our physical existence. Are you intimating the Dr. Steinhardt does not support the multiverse concept?

The idea is so compelling that cosmologists, including me, routinely describe it to students, journalists and the public as an established fact. Yet something peculiar has happened to inflationary theory in the 30 years since Guth introduced it. As the case for inflation has grown stronger, so has the case against. The two cases are not equally well known: the evidence favoring inflation is familiar to a broad range of physicists, astrophysicists and science aficionados. Surprisingly few seem to follow the case against inflation except for a small group of us who have been quietly striving to address the challenges. Most astrophysicists have gone about their business testing the predictions of textbook inflationary theory without worrying about these deeper issues, hoping they would eventually be resolved. Unfortunately, the problems have resisted our best efforts to date.

[seer]

Where does mu view differ from that od Dr. Steinhardt. What you cited is ok, but not complete. I agreed that the inflationary/multiverse is the current most widely accepted view of our physical existence. Are you intimating the Dr. Steinhardt does not support the multiverse concept?

The idea is so compelling that cosmologists, including me, routinely describe it to students, journalists and the public as an established fact. Yet something peculiar has happened to inflationary theory in the 30 years since Guth introduced it. As the case for inflation has grown stronger, so has the case against. The two cases are not equally well known: the evidence favoring inflation is familiar to a broad range of physicists, astrophysicists and science aficionados. Surprisingly few seem to follow the case against inflation except for a small group of us who have been quietly striving to address the challenges. Most astrophysicists have gone about their business testing the predictions of textbook inflationary theory without worrying about these deeper issues, hoping they would eventually be resolved. Unfortunately, the problems have resisted our best efforts to date.

Yes Steinhardt does not support the multiverse, read the link:

The Abyss of Infinity

Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space.Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing.

He explains this more in the link, see The perils of eternal inflation.

[shunyadragon]

Yes Steinhardt does not support the multiverse, read the link:



He explains this more in the link, see The perils of eternal inflation.

Nothing here rejects the possibility of a 'multiverse.' I have no problem with various models and theorems involving 'inflation,' but to support your argument you need to cite Dr. Steinhardt specifically where her rejects the possibility of a multiverse. The following does describe the potential of a multiverse, but yet, of course, Dr. Steinhardt questions over reaching conclusions concerning models and theorems concerning the nature of our physical existence based on our present knowledge.

Source: Dr. Steinhardt, The Perils of Inflation

The Abyss of Infinity

Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space. Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing.

© Copyright Original Source

In fact I am very much in agreement with Dr. Steinhardt.

[seer]

Nothing here rejects the possibility of a 'multiverse.' I have no problem with various models and theorems involving 'inflation,' but to support your argument you need to cite Dr. Steinhardt specifically where her rejects the possibility of a multiverse. The following does describe the potential of a multiverse, but yet, of course, Dr. Steinhardt questions over reaching conclusions concerning models and theorems concerning the nature of our physical existence based on our present knowledge.

Source: Dr. Steinhardt, The Perils of Inflation

The Abyss of Infinity

Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space. Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing.

© Copyright Original Source

In fact I am very much in agreement with Dr. Steinhardt.

You agree with what? He is saying that it is nonsense, i.e. concept of the multiverse. Did you even bother to read the perils of eternal inflation section?

[shunyadragon]

You agree with what? He is saying that it is nonsense, i.e. concept of the multiverse. Did you even bother to read the perils of eternal inflation section?

Seer, he is not saying that. He is describing possibilities of origins, and warning not to overstate the conclusions of the theorems and models of these origins. Again, please cite where Dr. Steinhardt rejects the possibility that multiverses exist.

Source: Dr. Steinhardt, The Perils of Inflation

The Abyss of Infinity

Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space. Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing.

© Copyright Original Source

In the history of modern science their is the quest for the theory that explains everything, particularly Einstein. In the above he warns and questions over stating these objectives and claims.

What you have to do is cite Dr. Steinhardt where he proposes that the multiverse concept is not a possibility. Still waiting . . .

You fail to realize that the models and theorems currently proposed and being developed consider 'multiverse' concepts as possibilities. It has never been claimed that there is proof that 'multiverses' exist.

I do not know of any physicists and cosmologists who reject the 'possibility' that multiverses exist, including Dr. Steinhardt.

[seer]

Seer, he is not saying that. He is describing possibilities of origins, and warning not to overstate the conclusions of the theorems and models of these origins. Again, please cite where Dr. Steinhardt rejects the possibility that multiverses exist.

Source: Dr. Steinhardt, The Perils of Inflation

The Abyss of Infinity

Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space. Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing.

© Copyright Original Source

In the history of modern science their is the quest for the theory that explains everything, particularly Einstein. In the above he warns and questions over stating these objectives and claims.

What you have to do is cite Dr. Steinhardt where he proposes that the multiverse concept is not a possibility. Still waiting . . .

You fail to realize that the models and theorems currently proposed and being developed consider 'multiverse' concepts as possibilities. It has never been claimed that there is proof that 'multiverses' exist.

I do not know of any physicists and cosmologists who reject the 'possibility' that multiverses exist, including Dr. Steinhardt.

What are you taking about Shuny, he is not saying that a multiverse can't exist but that the concept is nonsensical. Did you even read the Perils of Inflation section?

[shunyadragon]

What are you taking about Shuny, he is not saying that a multiverse can't exist but that the concept is nonsensical. Did you even read the Perils of Inflation section?

Please, read again, like your selective reading into selective quotes of Vilenkin, your again unethically misusing science. Nothing in Dr. Steinhardt's writings does ne indicate the multiverse is nonsensical. Your really diving into the void of the hyperbole. Please cite Dr. Steinhardt where he states that the multiverse is not a possible outcome of models and theorems of cosmology.

In this article Dr. Steinhardt is discussing the problems with different inflation models, and in no way rejecting the multiverse models. He does conclude there remains unanswered problems with all inflation models including what is proposed by Vilenkin in the BVG theorem. Please not the conclusions at the end of his article.

Source: http://www.physics.princeton.edu/~steinh/0411036.pdf

To be sure, I have presented the cases for and against inflation as two extremes without the opportunity for cross-examination or nuance. In a meeting held in January at the Princeton Center for Theoretical Science to discuss these issues, many leading theorists argued that the problems with inflation are mere teething pains and should not shake our confidence in the basic idea. Others (including me) contended that the problems cut to the core of the theory, and it needs a major fix or must be replaced.

In the end, the case will be decided by data. The forthcoming observations of the microwave background radiation will be telling. Experiments to search for a gravitational-wave imprint are already being conducted on mountaintops, in high-altitude balloons and onboard satellites, and results should emerge within the next two to three years. Detecting a gravitational-wave imprint would support inflation; failure to detect it would be a major setback. For inflation to make sense despite a null result, cosmologists would need to suppose that the inflaton field had a very peculiar potential with just the right shape to suppress gravitational waves, which seems contrived. Many researchers would gravitate to alternatives, like the cyclic universe theory, that naturally predict an unobservably small gravitational-wave signal. The outcome will be a critical moment in our quest to determine how the universe came to be the way it is and what will happen to it in the future.

© Copyright Original Source

[shunyadragon]

seer

You need to read mor of Dr. Steinhardt's work to fully understand his views on cosmology. He actually supports the possibility of a version of a cyclic cosmology for our universe, which would not be a contemporary inflation model.

Source: http://www.physics.princeton.edu/~steinh/vaasrev.pdf

The Cyclic Theory of the Universe

Abstract

The cyclic theory of the universe is a radical alternative to the standard big bang/inflationary scenario that offers a new approach for resolving the homogeneity, isotropy, and flatness problems and generating a nearly scale-invariant spectrum of fluctuations. The original formulation of the cyclic model was based on the picture suggested by M-theory in which the observable universe lies on a brane separated by a small gap along an extra dimension from a second brane. The cyclic model proposes that the big bang is a collision between branes that occurs at regular intervals; that each bang creates hot matter and radiation and triggers an epoch of expansion, cooling and structure formation; that there is an interbrane force responsible for drawing the branes together whose potential energy acts like dark energy when the branes are far apart; and that each cycle ends with the contraction of the extra dimension and a collision between branes – a new big bang – that initiates the next cycle. In more recent formulations, the cyclic model is realized with ordinary quantum field theory without introducing branes or extra dimensions. The key innovation common to all these models is the ekpyrotic phase, the period of ultra-slow contraction preceding the big bang. It is the ekpyrotic phase, rather than inflation, that is responsible for explaining the smoothness, flatness and large scale structure of the universe. It is also the ekpyrotic phase that generates the distinctive signatures in the spectrum of primordial gravitational waves and non-Gaussian density fluctuations that will be used to test the cyclic model in forthcoming experiments.

© Copyright Original Source

This is an example of where your selective reading of scientists gets you into trouble. Your jumping around selectively quoting Vilenkin to support an inflation universe or multiverse with a beginning, and infinite inflation, to Dr. Steinhardt, who questions the inflation models as inadequate, and proposes a possible cyclic universe that is possibly past and future infinite.

[Tassman]

No doubt Tass? Where is the evidence for your belief?

operate on the premise of a natural explanation for the functioning of the universe(s). And very successfully too! We've come a long way from the pre-scientific pocket-sized geocentric model we had four hundred years ago.

Still no evidence...

There is considerable