Can Multiverse theories be tested?

[QED]

[quote="In a paper titled "Scientific alternatives to the anthropic principle" Lee Smolin"]
It is explained in detail why the Anthropic Principle (AP) cannot yield any falsifiable
predictions, and therefore cannot be a part of science. Cases which have been
claimed as successful predictions from the AP are shown to be not that. Either they
are uncontroversial applications of selection principles in one universe (as in Dicke’s
argument), or the predictions made do not actually logically depend on any assumption
about life or intelligence, but instead depend only on arguments from observed
facts (as in the case of arguments by Hoyle and Weinberg). The Principle of Mediocrity
is also examined and shown to be unreliable, as arguments for factually true
conclusions can easily be modified to lead to false conclusions by reasonable changes
in the specification of the ensemble in which we are assumed to be typical.
We show however that it is still possible to make falsifiable predictions from theories
of multiverses, if the ensemble predicted has certain properties specified here.
An example of such a falsifiable multiverse theory is cosmological natural selection.
It is reviewed here and it is argued that the theory remains unfalsified. But it is very
vulnerable to falsification by current observations, which shows that it is a scientific
theory. [/quote]

To be "scientific" any theory has to be falsifiable. In recent debates it has been suggested that explanations for the existence of our universe based on the existence of one or more unseen other universes is unscientific due to being untestable. I have linked to Smolin's paper at the request of Confused and achilles12604 to show that it is indeed possible to develop a testable hypothesis of this nature. This new debate can serve to collect any criticism of this assertion.

[Confused]

[quote="In a paper titled "Scientific alternatives to the anthropic principle" Lee Smolin"]
It is explained in detail why the Anthropic Principle (AP) cannot yield any falsifiable
predictions, and therefore cannot be a part of science. Cases which have been
claimed as successful predictions from the AP are shown to be not that. Either they
are uncontroversial applications of selection principles in one universe (as in Dicke’s
argument), or the predictions made do not actually logically depend on any assumption
about life or intelligence, but instead depend only on arguments from observed
facts (as in the case of arguments by Hoyle and Weinberg). The Principle of Mediocrity
is also examined and shown to be unreliable, as arguments for factually true
conclusions can easily be modified to lead to false conclusions by reasonable changes
in the specification of the ensemble in which we are assumed to be typical.
We show however that it is still possible to make falsifiable predictions from theories
of multiverses, if the ensemble predicted has certain properties specified here.
An example of such a falsifiable multiverse theory is cosmological natural selection.
It is reviewed here and it is argued that the theory remains unfalsified. But it is very
vulnerable to falsification by current observations, which shows that it is a scientific
theory.

To be "scientific" any theory has to be falsifiable. In recent debates it has been suggested that explanations for the existence of our universe based on the existence of one or more unseen other universes is unscientific due to being untestable. I have linked to Smolin's paper at the request of Confused and achilles12604 to show that it is indeed possible to develop a testable hypothesis of this nature. This new debate can serve to collect any criticism of this assertion.[/quote]

I am not sure I am grasping what your getting at. Can the theories be tested based on a observational method, or by physics standards using the means of equations. Quantum physics have been debating multiverses for years now (personally I lean towards the string theory with at least 12 dimensions) and can't form a unified decision. In the nature of testable versus untestable: my reference was to the existance of the human spirit in the form of energy. It is understood that energy can be neither created nor destroyed, only changed. Please don't make me look through all my physics 101 or chem 101 books to provide this reference. I don't claim that at death, one can measure the release of energy from they human body and use it as a representation of the human spirit. Technology doesn't exist to test this hypothesis, but logically one can link the destruction of a body containing massive energy would in fact release this energy in some form. But your right in that it isn't testable/verifiable/or able to be validated. So I see your point. But not the relationship to can a multiverse theory be tested.

[QED]

OK, let me try to and present a little more background to this debate. First we have the notion of "falsifiability" -- a property that some explanatory theories posess and others don't. We can't expect anyone else to accept an explanation for some observation or other if we have no way in principle of disproving the theory. This arises because we might be able to come up with numerous competing explanatory theories and we would need to single one out for acceptance. For a theory to be "scientific" therefore, it needs to make predictions that can be tested and hence offer the potential for falsification.

Now there are some curious things about our universe and its laws. It apears to have had some sort of beginning and it has a handful of relations that are held in a ridiculously fine balance. These relations manifest themselves as things like the ratio of the strength of the gravitational force to the strength of the electromagnetic force for example. Becuase gravity affects the particle interactions that make up all the material in the universe (including us) the force of gravity must be around 10 raised to the 40th power times weaker than the force of electromagnetism.

There are only around half a dozen "magic numbers" like these, but their values are fantastically critical to the existence that we enjoy.

[Mightor]

Mightor say easy way to test exact amount energy in puny human body. Burn human body and measure heat given off, like measuring calories in puny donut.

Mightor say puny human String Theory probably bunch of mammoth droppings. Mightor say too bad, showed promise.

[achilles12604]

[quote="In a paper titled "Scientific alternatives to the anthropic principle" Lee Smolin"]
It is explained in detail why the Anthropic Principle (AP) cannot yield any falsifiable
predictions, and therefore cannot be a part of science. Cases which have been
claimed as successful predictions from the AP are shown to be not that. Either they
are uncontroversial applications of selection principles in one universe (as in Dicke’s
argument), or the predictions made do not actually logically depend on any assumption
about life or intelligence, but instead depend only on arguments from observed
facts (as in the case of arguments by Hoyle and Weinberg). The Principle of Mediocrity
is also examined and shown to be unreliable, as arguments for factually true
conclusions can easily be modified to lead to false conclusions by reasonable changes
in the specification of the ensemble in which we are assumed to be typical.
We show however that it is still possible to make falsifiable predictions from theories
of multiverses, if the ensemble predicted has certain properties specified here.
An example of such a falsifiable multiverse theory is cosmological natural selection.
It is reviewed here and it is argued that the theory remains unfalsified. But it is very
vulnerable to falsification by current observations, which shows that it is a scientific
theory.

To be "scientific" any theory has to be falsifiable. In recent debates it has been suggested that explanations for the existence of our universe based on the existence of one or more unseen other universes is unscientific due to being untestable. I have linked to Smolin's paper at the request of Confused and achilles12604 to show that it is indeed possible to develop a testable hypothesis of this nature. This new debate can serve to collect any criticism of this assertion.[/quote]

Bottom line. . . How does this individual purport that we "test" his idea? All the first 8 pages talked about was why the Anthropic Principal was not litterally science.

[QED]

Bottom line. . . How does this individual purport that we "test" his idea? All the first 8 pages talked about was why the Anthropic Principal was not litterally science.

I could compose a precis of the paper for you but it's really quite short (and I think reasonably understandable) as it is. Just looking at the contents page I would hope you could navigate to the information you want:

Code: Select all

1 Introduction
2 The problem of the undetermined parameters of physics and cosmology
3 The failure of unification to solve the problem
4 Mechanisms of production of universes 
4.1 Eternal inflation 
4.2 Bouncing black hole singularities 
4.3 Comparison of universe generation mechanisms
5 How do multiverse theories make predictions? 
5.1 Varieties of anthropic reasoning 
5.1.1 The theological anthropic principle 
5.1.2 Selection effects within one universe
5.1.3 False uses of an anthropic principle
5.1.4 Selection effects within a multiverse 
5.1.5 The principle of mediocrity 
5.1.6 Weinberg’s argument for the cosmological constant
5.1.7 Aguirre’s argument against the Anthropic Principle 
5.2 Natural Selection 
6 Predictions of Cosmological Natural Selection 
6.1 Successes of the theory
6.2 Previous criticisms
6.3 Why a single heavy pulsar would refute S
6.4 How observations of the CMB could refute S
6.5 How early star formation could refute S
7 Conclusions

Section 6 discusses the predictions of his theory and hence offers ways to test it. Remember -- I am not arguing that this particular or any other theory is correct, I am trying to establish the principle that such theories can be scientific. This principle is recognized by Smolin which is why I have drawn your attention to his particular paper.

[QED]

Confused -- sorry I haven't had time to reply to your post. A bit of an emergency has cropped up in the QED household that demands my fullest attention. I'll be getting back to this topic asap!

[Confused]

Confused -- sorry I haven't had time to reply to your post. A bit of an emergency has cropped up in the QED household that demands my fullest attention. I'll be getting back to this topic asap!

Hope for good outcome of the emergency. Await your return.

Michelle

[QED]

Thanks for you good wishes Confused. Emergency over now that a professional plumber has finished off the botched repair work that I started

I am not sure I am grasping what your getting at. Can the theories be tested based on a observational method, or by physics standards using the means of equations.

Smolin presents a particular theory in which our universe is but one of many (his theory is itself one of many that describe multiple universes). But his whole emphasis is on testability -- as he understands that to have scientific value (as opposed to purely philosophical value!) a theory must have some test(s) that could, in principle, falsify it. This demands an observational test as proof by equations alone are held to be inadequate. A neat example of why this is so might be any film made by Pixar (e.g. Toy Story or Monsters Inc.). These movies are entirely digitally generated worlds that are in themselves self-consistent. They could in principle be described by an equation but that doesn't make these worlds real in a practical sense. Likewise string theory might present a fully self-consistent world of its own but without sufficient predictions providing observational tests it will fail to be universally compelling .

Quantum physics have been debating multiverses for years now (personally I lean towards the string theory with at least 12 dimensions) and can't form a unified decision.

Smolin is himself a critic of string theory precisely because of its failure to make testable predictions so far.

In the nature of testable versus untestable: my reference was to the existence of the human spirit in the form of energy. It is understood that energy can be neither created nor destroyed, only changed. Please don't make me look through all my physics 101 or chem 101 books to provide this reference. I don't claim that at death, one can measure the release of energy from they human body and use it as a representation of the human spirit. Technology doesn't exist to test this hypothesis, but logically one can link the destruction of a body containing massive energy would in fact release this energy in some form. But your right in that it isn't testable/verifiable/or able to be validated. So I see your point. But not the relationship to can a multiverse theory be tested.

Surely whatever makes us us is very physical? After all, the tiniest amount of physical intervention in our bodies can result in no end of change to who and what we are. If "spirit" has anything to do with what makes one person different to another then we already know that this is a fragile "substance". Of course we can always postulate that spirit is immune from mechanical trauma but that would necessarily divorce person hood (which we know is fragile and mechanically dependent) from spirit therefore it seems to me that what (if anything) leaves the body on death could be nothing personal. A life-force identical to all other life-forces? Not worth the trouble speculating over in my view.

[Confused]

Thanks for you good wishes Confused. Emergency over now that a professional plumber has finished off the botched repair work that I started

I am not sure I am grasping what your getting at. Can the theories be tested based on a observational method, or by physics standards using the means of equations.

Smolin presents a particular theory in which our universe is but one of many (his theory is itself one of many that describe multiple universes). But his whole emphasis is on testability -- as he understands that to have scientific value (as opposed to purely philosophical value!) a theory must have some test(s) that could, in principle, falsify it. This demands an observational test as proof by equations alone are held to be inadequate. A neat example of why this is so might be any film made by Pixar (e.g. Toy Story or Monsters Inc.). These movies are entirely digitally generated worlds that are in themselves self-consistent. They could in principle be described by an equation but that doesn't make these worlds real in a practical sense. Likewise string theory might present a fully self-consistent world of its own but without sufficient predictions providing observational tests it will fail to be universally compelling .

Quantum physics have been debating multiverses for years now (personally I lean towards the string theory with at least 12 dimensions) and can't form a unified decision.

Smolin is himself a critic of string theory precisely because of its failure to make testable predictions so far.

In the nature of testable versus untestable: my reference was to the existence of the human spirit in the form of energy. It is understood that energy can be neither created nor destroyed, only changed. Please don't make me look through all my physics 101 or chem 101 books to provide this reference. I don't claim that at death, one can measure the release of energy from they human body and use it as a representation of the human spirit. Technology doesn't exist to test this hypothesis, but logically one can link the destruction of a body containing massive energy would in fact release this energy in some form. But your right in that it isn't testable/verifiable/or able to be validated. So I see your point. But not the relationship to can a multiverse theory be tested.

Surely whatever makes us us is very physical? After all, the tiniest amount of physical intervention in our bodies can result in no end of change to who and what we are. If "spirit" has anything to do with what makes one person different to another then we already know that this is a fragile "substance". Of course we can always postulate that spirit is immune from mechanical trauma but that would necessarily divorce person hood (which we know is fragile and mechanically dependent) from spirit therefore it seems to me that what (if anything) leaves the body on death could be nothing personal. A life-force identical to all other life-forces? Not worth the trouble speculating over in my view.

I think I grasp what you are saying. Because at this junction in my life, I can neither confirm, nor deny an existance of god/spirit/soul, I have to look at this from a neutral standpoint. Should the body possess a soul, it could be said that the soul leaving the body and transcending to heaven or hell is moving into another universe, but this is untestable and I doubt technology will ever exist that can prove a soul is released and moves to another universe. However, I believe that at some point, technology will be advanced enough to measure the amount of energy the body releases immediately upon death (not just the destruction of cells/tissues/etc, but the immediate release of energy stored in the brain in the form of electrical impulses that stimulate neurotransmitters/neurochemicals/homones that we identify as a the personality or soul) that where that energy then travels, ie. dispersed throughout the atmosphere without purpose to be recycled into other living organisms or as an entire unit with movement that mimics purpose or direction. Maybe its sci-fi wishing, but should we have the ability to see where this energy moves and should it disappear as a whole, it would defy the priciple that energy can't be destroyed, since we can't do that, perhaps it would be enough to start the direction of proving multiverses simply by proving the energy was there, then it wasn't and we know we can't destroy it, therefore, it may have moved to another dimension. I know, it's far fetched, but so is heaven.