On the thread, "steady state theory of biological origin," I've been talking about
the exquisite sensitivity of the fundamental constants of our universe
to tiny perturbations of their values that would make intelligent life impossible.
This is commonly referred to as the "fine tuning" of the constants.
The great astronomer and physicist Martin Rees has written a very readable book about six of these constants (_Just_Six_Numbers_) and how they determine so much of the structure of our universe. I was first attracted
to this book by its contribution to the fine tuning problem, but I am coming more and more each day to appreciate the fascinating information it provides about the nature of our physical world.
One of the constants relates the force of gravity to the force of repulsion of one proton for another. The latter is about 10^36 [1 with 36 zeroes after it]much larger. Gravity would crush anything as large as ourselves.
times as strong as the former. Rees comments on page 30:
"What would happen if [gravity] were not quite so weak? Imagine, for instance, a universe where gravity was `only' 10^30 instead of 10^36 feebler than electric forces. ... even insects would need thick legs to support them, and no animals could get
...
"Instead of living for ten billion years, a typical star would live for about 10,000 years. ... exhaust[ing] its energy before even the first steps in organic evolution had got under way."
Unlike some others of the six constants, the sensitivity to perturbations only works in one direction. Rees adds the following comments in the same page:
"The converse, however, is that an even weaker gravity could allow even
more elaborate and longer-lived structures to develop.
...
"Paradoxically, the weaker gravity is (provided that it isn't actually equal to zero) the grander and more complex can be its consequences."
I have sometimes written about the possibility of the multiverse including universes
far "grander" than ours, one of which might have produced a superhuman race which had the power to alter material in black holes to produce a
much smaller-scale and shorter-lived universe -- ours! -- based on just a few constants.
In my next post to this thread tomorrow, I will begin to approach this exalted standard of grandness
by imagining a universe where gravity is something like 10^42 times as feeble
as electric forces. What might we expect of the abilities of intelligent inhabitants
on an appropriately huge planet?
Peter Nyikos
Professor, Dept. of Mathematics -- standard disclaimer--
University of South Carolina
http://people.math.sc.edu/nyikos
On Wednesday, April 12, 2023 at 10:35:19 PM UTC-4, peter2...@gmail.com wrote:
On the thread, "steady state theory of biological origin," I've been talking about
the exquisite sensitivity of the fundamental constants of our universe
to tiny perturbations of their values that would make intelligent life impossible.
This is commonly referred to as the "fine tuning" of the constants.
The great astronomer and physicist Martin Rees has written a very readable book about six of these constants (_Just_Six_Numbers_) and how they determine so much of the structure of our universe. I was first attracted to this book by its contribution to the fine tuning problem, but I am coming
more and more each day to appreciate the fascinating information it provides
about the nature of our physical world.
much larger. Gravity would crush anything as large as ourselves.One of the constants relates the force of gravity to the force of repulsion
of one proton for another. The latter is about 10^36 [1 with 36 zeroes after it]
times as strong as the former. Rees comments on page 30:
"What would happen if [gravity] were not quite so weak? Imagine, for instance, a universe where gravity was `only' 10^30 instead of 10^36 feebler than electric forces. ... even insects would need thick legs to support them, and no animals could get
...
"Instead of living for ten billion years, a typical star would live for about 10,000 years. ... exhaust[ing] its energy before even the first steps in organic evolution had got under way."
Unlike some others of the six constants, the sensitivity to perturbations only works in one direction. Rees adds the following comments in the same page:
"The converse, however, is that an even weaker gravity could allow even more elaborate and longer-lived structures to develop.
...
"Paradoxically, the weaker gravity is (provided that it isn't actually equal to zero) the grander and more complex can be its consequences."
I have sometimes written about the possibility of the multiverse including universes
far "grander" than ours, one of which might have produced a superhuman race
which had the power to alter material in black holes to produce a
much smaller-scale and shorter-lived universe -- ours! -- based on just a few constants.
In my next post to this thread tomorrow, I will begin to approach this exalted standard of grandness
by imagining a universe where gravity is something like 10^42 times as feeble
as electric forces. What might we expect of the abilities of intelligent inhabitants
on an appropriately huge planet?
Probabilities and the Fine‐Tuning Argument: a Sceptical View
Timothy McGrew, Lydia McGrew, Eric Vestrup
Mind, Volume 110, Issue 440, October 2001, Pages 1027–1038, https://doi.org/10.1093/mind/110.440.1027
Abstract
Proponents of the Fine‐Tuning Argument frequently assume that
the narrowness of the life‐friendly range of fundamental physical constants implies a low probability for the origin of the universe
‘by chance’. We cast this argument in a more rigorous form than
is customary and conclude that the narrow intervals do not yield
a probability at all because the resulting measure function is non‐normalizable. We then consider various attempts to circumvent
this problem and argue that they fail.
[...]On Wednesday, April 12, 2023 at 10:35:19 PM UTC-4, peter2...@gmail.com wrote:
I have sometimes written about the possibility of the multiverse including universes
far "grander" than ours, one of which might have produced a superhuman race
which had the power to alter material in black holes to produce a
much smaller-scale and shorter-lived universe -- ours! -- based on just a few constants.
In my next post to this thread tomorrow, I will begin to approach this exalted standard of grandness
by imagining a universe where gravity is something like 10^42 times as feeble
as electric forces. What might we expect of the abilities of intelligent inhabitants
on an appropriately huge planet?
In other words, we are imagining a universe where gravity is a million times weaker than it is in our universe.
PS My next post to this thread will be some time this evening.
Meanwhile, some readers might like to ponder the question of
what biology could be like on a planet with 10,000 times the surface area of earth...
On Thursday, April 13, 2023 at 5:20:19 AM UTC-4, Lawyer Daggett wrote:
On Wednesday, April 12, 2023 at 10:35:19 PM UTC-4, peter2...@gmail.com wrote:
On the thread, "steady state theory of biological origin," I've been talking about
the exquisite sensitivity of the fundamental constants of our universe to tiny perturbations of their values that would make intelligent life impossible.
This is commonly referred to as the "fine tuning" of the constants.
The great astronomer and physicist Martin Rees has written a very readable
book about six of these constants (_Just_Six_Numbers_) and how they determine so much of the structure of our universe. I was first attracted
to this book by its contribution to the fine tuning problem, but I am coming
more and more each day to appreciate the fascinating information it provides
about the nature of our physical world.
much larger. Gravity would crush anything as large as ourselves.One of the constants relates the force of gravity to the force of repulsion
of one proton for another. The latter is about 10^36 [1 with 36 zeroes after it]
times as strong as the former. Rees comments on page 30:
"What would happen if [gravity] were not quite so weak? Imagine, for instance, a universe where gravity was `only' 10^30 instead of 10^36 feebler than electric forces. ... even insects would need thick legs to support them, and no animals could get
...
"Instead of living for ten billion years, a typical star would live for about 10,000 years. ... exhaust[ing] its energy before even the first steps in organic evolution had got under way."
Unlike some others of the six constants, the sensitivity to perturbations
only works in one direction. Rees adds the following comments in the same page:
"The converse, however, is that an even weaker gravity could allow even more elaborate and longer-lived structures to develop.
...
"Paradoxically, the weaker gravity is (provided that it isn't actually equal to zero) the grander and more complex can be its consequences."
I have sometimes written about the possibility of the multiverse including universes
far "grander" than ours, one of which might have produced a superhuman race
which had the power to alter material in black holes to produce a
much smaller-scale and shorter-lived universe -- ours! -- based on just a few constants.
In my next post to this thread tomorrow, I will begin to approach this exalted standard of grandness
by imagining a universe where gravity is something like 10^42 times as feeble
as electric forces. What might we expect of the abilities of intelligent inhabitants
on an appropriately huge planet?
In other words, we are imagining a universe where gravity is a million times weaker than it is in our universe. For a planet to have the same gravitational
pull on its surface as earth, it would have to be a million times as massive.
That corresponds to having a hundred times the radius, and 10,000 times the surface area.
Probabilities and the Fine‐Tuning Argument: a Sceptical ViewThank you for this reference, Daggett. I will look at it before too long, because it appeals to my mathematical background, which has
Timothy McGrew, Lydia McGrew, Eric Vestrup
made me aware of the pitfalls of probability theory.
Mind, Volume 110, Issue 440, October 2001, Pages 1027–1038, https://doi.org/10.1093/mind/110.440.1027
It may also be relevant to this whole theme of how fine tuning affects our expectations of how a "typical" universe should look.
However, this thread is not about fine tuning. It is about exploring universes
that seem much more favorable to the development of intelligent life
than our own; specifically, life of a much higher level of intelligence
and abilities than our own.
Abstract
Proponents of the Fine‐Tuning Argument frequently assume that
the narrowness of the life‐friendly range of fundamental physical constants implies a low probability for the origin of the universe
‘by chance’. We cast this argument in a more rigorous form than
is customary and conclude that the narrow intervals do not yield
a probability at all because the resulting measure function is non‐normalizable. We then consider various attempts to circumvent
this problem and argue that they fail.
By making the space of possibilities so enormous, the author[s]
[seem] quite ready to acknowledge the possibility of a universe
where gravity is much more feeble compared to electric forces than our own. And this thread is about possibilities, not probabilities.
By the way, it's a 2001 paper. Any idea of how it has been received by the scientific
and the philosophical and mathematical communities since then?
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