Fine Tuning?

Several fashionable speculations in cosmology, e.g., Smolin's
cosmological evolution, multiverse notions and anthropic just-so
stories are predicated on the assumption of fine tuning. The argument
is basically that if the laws of physics and the values of specific
constants were different, then we would not be here and the observable
universe would have different physics. Then the assertion is made that
either the cosmos is fine tuned, or there are an infinite number of
different universes and we just happen to exist in one that allows for
our existence.

But the starting assumption is that the laws of physics and the values
of constants could be different at different places in the Universe. A
contrary assumption is that the laws and constants are the same
throughout the Universe.

Do we have any scientific justification for choosing between these two
mutually exclusive assumptions?

Is it scientifically sound to assume that there is cosmological fine
tuning, and it must be explained, when there appears to be an equally
valid contradictory assumption that requires no fine tuning?

In article , "Robert L.
Oldershaw" writes:

Several fashionable speculations in cosmology, e.g., Smolin's
cosmological evolution, multiverse notions and anthropic just-so
stories

Please use a non-pejorative term to allow for a sensible discussion.

are predicated on the assumption of fine tuning.

Right.

The argument
is basically that if the laws of physics and the values of specific
constants were different, then we would not be here and the observable
universe would have different physics.

That's a major part of the argument.

Then the assertion is made that
either the cosmos is fine tuned, or there are an infinite number of
different universes and we just happen to exist in one that allows for
our existence.

There doesn't have to be an infinite number, just a large enough one.

There is another possible explanation: For some deep reason, the laws
couldn't be any different, and they just happen to allow our existence.
Both fine-tuning and anthropic arguments imply that they COULD be
different, at least in principle.

But the starting assumption is that the laws of physics and the values
of constants could be different at different places in the Universe. A
contrary assumption is that the laws and constants are the same
throughout the Universe.

You need to define "universe" here.

Do we have any scientific justification for choosing between these two
mutually exclusive assumptions?

Many would argue that we should choose the former because if we choose
the latter we know no reason why certain constants have the values they
do.

Is it scientifically sound to assume that there is cosmological fine
tuning, and it must be explained, when there appears to be an equally
valid contradictory assumption that requires no fine tuning?

What is that assumption? Also, it is unclear, at least to me, which of
the two you think requires fine tuning and which doesn't.

Op maandag 16 juni 2014 08:48:39 UTC+2 schreef Robert L. Oldershaw:
Several fashionable speculations in cosmology, e.g., Smolin's
cosmological evolution, multiverse notions and anthropic just-so
stories are predicated on the assumption of fine tuning. The argument
is basically that if the laws of physics and the values of specific
constants were different, then we would not be here and the observable
universe would have different physics. Then the assertion is made that
either the cosmos is fine tuned, or there are an infinite number of
different universes and we just happen to exist in one that allows for
our existence.

IMO it does not make sense to discuss different laws of physics.
Different laws imply different physics. The laws are a description.
Different physics imply that if you drop a ball the bounced ball could be
higher. This happens on the moon but that is not what you want. It should
bounce higher here on earth.
Difference physics imply that the chemical elements of the periodic table
are "different". That H2O is not water. That water does not boil.
Difference physics imply that there are no electrons etc etc
Different physics can imply that there is no life possible. etc etc.
You can discuss different physics in all different forms, shapes and grades
but what is the importance?

(*) The only thing that make sense is to try to understand what is happening
what has happened and what will happen everywhere as accurate as possible.

But the starting assumption is that the laws of physics and the values
of constants could be different at different places in the Universe. A
contrary assumption is that the laws and constants are the same
throughout the Universe.

The only statement you can make is that laws can be modified.
Modifying means in general that more parameters (factors) are considerd
to describe the physical behaviour of what you are studying more accurate.

Is it scientifically sound to assume that there is cosmological fine
tuning, and it must be explained, when there appears to be an equally
valid contradictory assumption that requires no fine tuning?

To solve above (See *) fine tuning (defined as ?) is no issue.

There is one (?) exception.
It only makes sense to discuss different forms of evolution (theory)
happening in different places (planets),
assuming that the laws of physics are the same, in Our Universe.


Nicolaas Vroom
http://users.pandora.be/nicvroom/