The
idea discussed in previous posts satisfies Smolin's requirements for
explaining why our universe has the laws it does.

There
is a mathematical structure T that is a formal system such that 1. T
contains the necessity modal operator and 2. T can refer to itself,
and it satisfies the condition

1)

i.e.,
T implies necessarily necessarily ... necessarily T exists.

T
in some sense it has the most right to exist.

One
still has to interpret time and quantum probabilities in this
mathematical object.

The
physical universe is identified with T. One looks for the structure
(1) in the laws of the universe. It becomes an physical assertion
that the existence of the universe is (maximally) necessary.

In
Smolin's language T is in a post-Newtonian paradigm.

See
previous posts.

Smolin:

"1)
The Newtonian paradigm takes the dynamical law as input. It cannot be
the basis

of
explaining why that law is the one that applies to our universe.
Hence to adopt

this
paradigm as the framework of a cosmological theory will leave a great
deal of

mystery
in our understanding of the world. We will fail to fulfill the demand
to give

sufficient
reason for every cosmological question.

2)
Similarly, the Newtonian paradigm takes the specification of the
initial state as input.

It
cannot justify or explain the choice of initial state. The demand for
sufficient

reason
will again not be answered.

3)
The Newtonian paradigm assumes that there is an absolute distinction
between the

role
of state and the role of the dynamical law. This distinction can be
operationally

realized
on small subsystems because we can prepare a system many times in
different

initial
states and observe what aspects of the resulting evolution are
universal

and
what are consequences of the choice of initial state. The dynamical
law is inferred

from
observations of universal features of the motion which are
independent

of
the choice of initial state. When we come to the universe there is
only a single

history
and so we have no way to operationally or experimentally distinguish
the

role
of the law from the choice of initial state.

This
can be a practical as well as a theoretical issue because there can
be degeneracies

in
cosmological models arising from the fact that a single observation
can be

explained
equally well by modifying the law of motion or the choice of initial
conditions.

One
sees examples of this in attempts to fit inflationary models to data
such

as
the possible non-guassianities[26].

4)
Any theory formulated in the Newtonian paradigm will have an infinite
number of

solutions.
But, the universe is unique-so only one cosmological history is
physically

real.
The Newtonian paradigmis then very extravagant when applied to
cosmology

because
it not only makes predictions about the future of the one real
universe, it

offers
predictions for an infinite number of universes which are never
realized. The

Newtonian
paradigm cannot explain why the one solution that is realized is
picked

out
from the infinite number of possibilities."

See

A
perspective on the landscape problem

Lee
Smolin

Perimeter
Institute for Theoretical Physics,

31
Caroline Street North, Waterloo, Ontario N2J 2Y5, Canada

February
16, 2012

Abstract

I
discuss the historical roots of the landscape problem and propose
criteria for its

successful
resolution. This provides a perspective to evaluate the possibility
to solve

it
in several of the speculative cosmological scenarios under study
including eternal

inflation,
cosmological natural selection and cyclic cosmologies.

Invited
contribution for a special issue of Foundations of Physics titled

*Forty Years**Of String Theory: Reflecting On the Foundations.*

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