Page 2 of 2
Re: Why physical constants?
Posted: September 11th, 2013, 5:47 am
by Geordie Ross
Xris wrote:
(Nested quote removed.)
This theory does not deny fine tuning it simply theorises on the idea that it was pure chance that this universe was finely tuned. But as they have no proof of alternatives it is just a theory. Natural selection does not deny a determined formula to create life and evolve. There is nothing random or given over to chance with evolution. How you define fine tuning with natures ability I do not know.But if you give nature the same circumstances and opportunity it will perform to a set of rules. Is that fine tuning?
Firstly, its not a theory, its a hypothesis, secondly, 'fine tuning' implies a fine tuner, this offers a counter explanation to intelligent design argument without the need for supernatural deities.
Re: Why physical constants?
Posted: September 11th, 2013, 7:08 am
by Xris
Geordie Ross wrote:
(Nested quote removed.)
Firstly, its not a theory, its a hypothesis, secondly, 'fine tuning' implies a fine tuner, this offers a counter explanation to intelligent design argument without the need for supernatural deities.
Not sure what you are suggesting. Does this indicate that if this hypothesis is proven wrong there is a fine tuner?
Re: Why physical constants?
Posted: September 11th, 2013, 7:09 am
by Rilx
Philosophy Explorer wrote:Why do physical constants exist in this universe? We have the gravitational constant, Planck's constant and the speed of light (in a vacuum) as a few examples. A quick check on the internet indicates this is an open question.
I'm speculating how this came about and I have no quick answers. Maybe someone would like to tackle this problem.
I don't think they exist "in this (natural) universe". They exist in human science and its standards and measures. For instance, our decimal system originates from the number of our fingers - not very coherent with gravity or the speed of light.
I understand physical constants as interfaces between nature and human explanations of nature.
Re: Why physical constants?
Posted: September 11th, 2013, 10:43 am
by Xris
We have to accept that certain constants do maintain the universe. Those constants can not be changed even slightly before we would see the universe collapse and cease to exist as we know it. But the question would be the same even if we did not know about these constants.Our ancestors still had to ask the same questions. Why does the universe exist at all? It does become more of a dramatic question if you believe in the BB. It infers that the laws had to be predetermined. We have to accept some magical act managed to ignore all these laws for the first few seconds and then they suddenly decided to be as we know them. It requires a leap of faith to believe the natural laws can be so understanding as to know precisely when to change. It beggars belief.
Re: Why physical constants?
Posted: September 12th, 2013, 5:57 am
by Dolphin42
A side note on this subject:
The particular sizes of many universal constants are a consequence of the "human scale" units in which we choose to express them. Planck's constant, for example, is very small when expressed in metres, kilograms and seconds because these units have been chosen to be useful at everyday scales of space, mass and time. It would be perfectly possible to create a set of units in which Planck's constant is unity. So the interesting questions are more about the relative sizes of different constants, when expressed in the same units, and about the constants, like pi, which have no units because they are ratios.
I think the question of why they have these relative sizes is essentially the same as the question of why physical laws appear to exist in the particular form that they do at all. It's the question: why does the universe have structure and order and why does it have the particular type of structure that it does? And, as people have mentioned here, there are various possible answers involving such things as the anthropic principle and/or cosmological natural selection.
Re: Why physical constants?
Posted: September 12th, 2013, 7:32 am
by TimBandTech
Rilx wrote:
(Nested quote removed.)
I don't think they exist "in this (natural) universe". They exist in human science and its standards and measures. For instance, our decimal system originates from the number of our fingers - not very coherent with gravity or the speed of light.
I understand physical constants as interfaces between nature and human explanations of nature.
This is a pretty excellent interpretation on Rilx's part. Consider that from naught we must construct a theory of the physical universe. Consider that we are evolved from apes, and that our system of language may be constrained by genetic rules. A reasonably first theory of the universe is to suppose that Somebody made it, but this personification is a naive attempt. Observant and experimental humans have come to be masters of materials, but this does not mean that we understand why those materials exist.
When we can derive the electron (with spin) there will be less constants. When we can derive spacetime then there will be less constants. For now these devices are empirical in their treatment, and clean theory cannot rest upon an empirical base. Still, from naught some primitives must start somewhere. We are engaged in such a progression. We are so gullible to believe that modern science deserves a bow deeper that god. We are likely wrong about many things, and on a few of those things I can substantiate. Why is thermal conductivity so slow? There is no answer to this in modern thermodynamics, yet they will act as if their subject is pristine and any who fail to obey its rules are merely lesser humans or physicists. Well, gullibility and mimicry rule the day, for we are merely social animals and we cannot so readily escape those constraints. If our language carries a false structure to the one of the universe then we will be in need of a gene splice to remedy the situation. When we build an orb so intelligent as to derive the electron it may not have any clean interpretation to feed back to us. Oh, I will be the dinosaur of another day, but that's not all they'll say...
Re: Why physical constants?
Posted: September 12th, 2013, 8:01 am
by Dolphin42
Tim. I think you're doing the same thing that many many people have done on this forum: placing science on a pedestal so that you can knock it off.
Re: Why physical constants?
Posted: October 19th, 2017, 5:10 am
by Steve3007
Today is the 107th birthday of Subrahmanyan Chandrasekhar. Discoverer of the famous Chandrasekhar limit, which is 1.4 solar masses.
Perhaps the ultimate accolade is to be associated with a significant number. Planck. Avogadro. Joseph Heller. Boltzmann. I could go on.
Happy birthday Subrahmanyan.
Re: Why physical constants?
Posted: October 23rd, 2017, 4:59 pm
by Mechsmith
The speed of light (c) is only to an observer. Consequently the observer and the observed light must be subjected to the same gravitational field, and consequently again to the same speed of time.
Now what happens if you move the observer to the event horizon of a "Black Hole"?
I think that will show that (c) is location dependent. Or perhaps that the speed of time is.
I have noticed that if we regard (c) as a constant then the speed of time changes. The converse is also true.
Click on, (to enhance confusion further) "The Harvard Tower Experiments)
Re: Why physical constants?
Posted: October 24th, 2017, 4:53 am
by SimpleGuy
The estimation for those constants is mostly a regression line or polynomial. What most of the people don't understand is, that if one uses a regression line as an estimator for a constant in physics , the regression line functional has a confidence-interval dependent on the measure point which is dependent on the made measurment. This should be clear if a measurement has a dense point set in some regions and some scattered point in another region not only the slope or the rise of the regression line has a variance but every measure point then has for the corresponding line a functional estimator f(x)=a x_meas +b . But this estimator has a confidence in which is dependent on x_meas so $f(x_meas) \in [m-conf_low, m+conf_high]$ but this is dependent on the point. Some regions are densly measured others small. This is normally not taken into account of the corresponding considerations.
-- Updated October 24th, 2017, 4:55 am to add the following --
So it could be, that from a statistical viewpoint so called constants are for some parameter intervall in such big confidence intervalls, that those number are no constants at all.
-- Updated October 24th, 2017, 5:07 am to add the following --
Just assume a function wich is constant in the middle of it's measured intervall, but then rises on both edges of the intervall. If one takes many points for estimation of a regression line in the middle as measurements, an just two or three pertubed to the outside which still fit the regression model one has an extremely low variance for the regression line although the confidence interval at the edges of the intervall rises in it's extent very fast. Many people would claim that this is a constant . This is even more severe if this problem in non-linearly coupled into other equations.
-- Updated October 24th, 2017, 5:22 am to add the following --
So the socalled constant functional f(x)= 0*x +b is a good estimator for the middle points as a hypothesis but a bad estimator at the border of the intervall although the variance of the slope close to 0 is small (as well as the variance of b).
-- Updated October 24th, 2017, 8:01 am to add the following --
Even for statistical learning, neural networks and bayesian learning algorithms this is important. Another thing would be , that one doesn't use the variance but median as a measurment for calculation of the confidence intervals.
Re: Why physical constants?
Posted: October 24th, 2017, 6:03 pm
by Atreyu
Dolphin42 wrote:I think the question of why they have these relative sizes is essentially the same as the question of why physical laws appear to exist in the particular form that they do at all. It's the question: why does the universe have structure and order and why does it have the particular type of structure that it does? And, as people have mentioned here, there are various possible answers involving such things as the anthropic principle and/or cosmological natural selection.
I agree. I think the question 'Why are there physical constants?' can basically be reduced to 'Why is there some apparent order in the Universe, rather than apparent complete chaos?' And I also basically agree with your statement of proposed solutions.
I myself basically explain the apparent order as being the result of the fact that the Universe itself is actually a Conscious entity, and this
implies a necessary corresponding order in phenomena. Consciousness implies order, because it cannot exist in a state of complete chaos.
Re: Why physical constants?
Posted: October 25th, 2017, 7:54 am
by Steve3007
A lot of physical constants are conversion factors between different man-made units. Like the conversion between centimetres and inches, or Celsius and Fahrenheit. I guess the speed of light can be seen as the conversion factor between two different man-made units of "spacetime interval". Units of metres and units of seconds. Giving us the number of metres that are equivalent to one second. i.e. m/s.