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R. N. Mohapatra
are. Perhaps one day, detailed calculations using Quantum Chromodynamics
(QCD) would explain this. In that case, one could ask why the mass scale of
QCD which goes into this calculation is what it is, and on and on.
There are many free parameters in the standard model, which do not have
much to do with the structure of the universe or the existence of life. Examples
are the masses of the charm, top or bottom quarks, the QCD CP violating
parameter known as θ parameter, and the mixing of different quarks among
themselves. If their values were very different, it would not affect the growth
of the universe or the existence of life. So those parameters cannot rely on
the anthropic principle for their understanding, and must be understood
using objective reasoning from physical principles. There are therefore many
challenges for theoretical physicists even if the anthropic principle is used to
explain some of them. Thus anthropic principle does not completely bypass
the need for active research into understanding the basic forces and matter.
In some interpretations of the anthropic principle, it can appear as if the
existence of human life is a prerequisite for physical laws, since every aspect
of a physical law would appear (according to this) to be designed to make life
possible. This would be something difficult to accept. Whether the anthropic
principle finally remains as part of scientific discourse or not, the anthropic
arguments could be around for a long time (maybe forever) in some form,
until all the physically important parameters necessary for life and the universe
are fully understood, starting with a basic set of physical laws (it is unlikely to
be soon or even ever). Perhaps the examples given here, such as Hoyle state,
proton mass, etc. can one day be fully understood from basic principles of
forces and matter. Can the anthropic arguments be completely discarded? It
would appear not, if string theory is established as the ultimate theory of the
universe. That is because the multiple ground state (or lowest energy state)
problem of string theories may always require some sort of anthropic argument
to justify the universe we live in, as well as the success of the standard model.
But then maybe string theory does not have much to do with physics, or it
may happen that there will be so much progress in string theory that one day,
it will determine which one out of the 10
500 universes (or ground states) we
live in. Only time will tell.
R. N. Mohapatra
are. Perhaps one day, detailed calculations using Quantum Chromodynamics
(QCD) would explain this. In that case, one could ask why the mass scale of
QCD which goes into this calculation is what it is, and on and on.
There are many free parameters in the standard model, which do not have
much to do with the structure of the universe or the existence of life. Examples
are the masses of the charm, top or bottom quarks, the QCD CP violating
parameter known as θ parameter, and the mixing of different quarks among
themselves. If their values were very different, it would not affect the growth
of the universe or the existence of life. So those parameters cannot rely on
the anthropic principle for their understanding, and must be understood
using objective reasoning from physical principles. There are therefore many
challenges for theoretical physicists even if the anthropic principle is used to
explain some of them. Thus anthropic principle does not completely bypass
the need for active research into understanding the basic forces and matter.
In some interpretations of the anthropic principle, it can appear as if the
existence of human life is a prerequisite for physical laws, since every aspect
of a physical law would appear (according to this) to be designed to make life
possible. This would be something difficult to accept. Whether the anthropic
principle finally remains as part of scientific discourse or not, the anthropic
arguments could be around for a long time (maybe forever) in some form,
until all the physically important parameters necessary for life and the universe
are fully understood, starting with a basic set of physical laws (it is unlikely to
be soon or even ever). Perhaps the examples given here, such as Hoyle state,
proton mass, etc. can one day be fully understood from basic principles of
forces and matter. Can the anthropic arguments be completely discarded? It
would appear not, if string theory is established as the ultimate theory of the
universe. That is because the multiple ground state (or lowest energy state)
problem of string theories may always require some sort of anthropic argument
to justify the universe we live in, as well as the success of the standard model.
But then maybe string theory does not have much to do with physics, or it
may happen that there will be so much progress in string theory that one day,
it will determine which one out of the 10
500 universes (or ground states) we
live in. Only time will tell.